# 1941: the best airframe for a single engined fighter



## tomo pauk (Mar 31, 2012)

In other words, this time on we should discuss the capabilities of the airframe, independently from the engine it was mounted on it. What designer/manufacturer got it best? The capabilities to be accounted for are "upgradedeability", structural strength, capacity for decent firepower fuel tankage, suitability for engines different that the original, adaptability to work as bomber and/or reccon plane, pilot protection, ability to lend itself for the mass production etc. The carrier-borne planes yield no points for such capabilities.

Again, we will NOT look at the engines historically installed, nor the abilities acquired by the engines aboard, but the categories inherent to the airframe.


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## davebender (Mar 31, 2012)

Can use a variety of engines including BMW801 radial and DB603 V12.
Wide track landing gear.
Bubble canopy.
Standard airframe carried enough fuel for most missions. Space for wing tanks if you need extreme range.
Designed for high speed maneuverability which was becoming more important as engines became more powerful.
Space for 4 cannon in wings if desired.
No bad handling habits. Very important for green wartime pilots.
Inexpensive to mass produce.
Can be adapted into a relatively effective CAS aircraft.


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## parsifal (Mar 31, 2012)

IMO the Japanese A6M was the best airframe in 1941. Its subsequent failure was due to poor engine development, not so much a failure of the airframe. And in 1941 it contained all the best ingredients for fighters, bar one.....structural defence. That was a conscous choice brought about by the engines available


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## jim (Mar 31, 2012)

I choose Machi Mc 202
a)Liquid engine with the best possible solution for the radiator b) good landing gear c) capabilityfor cental cannon d)wings that -in mc205 -recieved internal cannons, d) higly manouverable e) adequate structure strength e) development potentional.Db 605 was installed with almost no modifications to produce Mc205 in 1942 and Mc206 was proposed with Db603 though more extensive modifications were needed f) almost performance parity with Bf 109F and Spitf V on less power and italian propeller of lower performance.. I believe that a Db 601E powered Mc 202 with 20mm engine cannon would be easily the best fighter of the year A big disadvantage was the time and cost of its production

Mr Dave bender
All the positives of Fw that you mentioned are true but led to the fact that the airframe required more power to be competitive with similar timed european fighters .Late in the war 109s on B4(plus Mw50) clearly outperformed Antons on C3 fuel and bigger capacity engine!Also while its landing gear was good for green pilots, its very high wing loading wasnt. Also although its high speed stall could be exploied usefully by experienced pilots, it certainly was a flaw. Too heavy to use DB605 (35 lt engine) despite the fact that it was of similar size with the Spitfire (27 lt engine) and only slightly bigger than Bf 109


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## davebender (Mar 31, 2012)

> Late in the war 109s on B4(plus Mw50) clearly outperformed Antons on C3 fuel


Not the fault of the Fw-190 airframe. Stick an overweight radial engine in the Me-109 or Spitfire and performance will suffer just as happened with the Fw-190.


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## wuzak (Mar 31, 2012)

Historically you could look at the Spitfire airframe as one which was developed heavily. Though the airframe did change the basics remained the same - and the Spitfire V airframe spawned the IX and the XII.


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## wuzak (Mar 31, 2012)

Or you could say the P-51 was an airframe waiting for an engine worthy of it....


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## davebender (Mar 31, 2012)

I agree and that engine was a DB603 or RR Griffon. Too bad it didn't get either one except for a few post-war P-51 racing aircraft.


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## buffnut453 (Mar 31, 2012)

parsifal said:


> IMO the Japanese A6M was the best airframe in 1941. Its subsequent failure was due to poor engine development, not so much a failure of the airframe. And in 1941 it contained all the best ingredients for fighters, bar one.....structural defence. That was a conscous choice brought about by the engines available



Apart from the tendency of the controls to stiffen significantly above 300 kts.


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## GregP (Apr 1, 2012)

The F4U Corsair generally outperforned anything it went up against.

It first flew in May 1940 but was not introduced until 1942. Nevertheless, it was available, was fast, rolled well, climbed with the best, was robust and was decently armed. Great potential.

If that mount is not in the population, I suggest the Me 109 as one of the obvious best in 1941. It certainly shot down more enemy aircaft than any other plane in history. Whatever the characteristics of the other fighters, the Me 109 was the fighter with the most shootdowns of enemies. Want a good performance measure? How about combat results. The Me 109 had them, in spades. Nothing else even comes close, though some piston fighers obviously outperforme it. Coult be the plane, could be the pilots, could be the environment in which it was utilized, and is likely a combination of the three but the Me 109 was a winner from the first flight. just the top three aces in Me 109's shot down 950+ enemy aircraft. 

Can any aircraft of any time in any war claim better combat performance? No. Not even CLOSE.


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## Dcazz7606 (Apr 1, 2012)

In Warren Bodie's, Thunderbolt he has a few interesting pictures of the airframe of a P-47N. Republic called it "the Skinnless Hotdog" so Republic empoyees who worked on a component of the P-47 could see how complicated the plane really was and try the controls from a remote station. It gives a great view of all the equipment stuffed into the plane. No wonder it could survive.


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## drgondog (Apr 1, 2012)

For me the best AIRFRAME was the P-51. It was the original airframe with 4 x20mm, had slightly more drag than the P-51B, and achieved excellent airspeeds with an engine operating at only 60% of its more famous successors. 

From the time its immediate successor, the Mustang I and P-51A's rolled off the assembly lines it would remain the lowest drag operational reciprocating engine driven fighter.

The airframe was altered to accept the Packard Merlin, achieving alightly better aerodynamics, and continued with same or better aerodynamics as the original production version through every modification and growth of gross weight. 

It (P-51 and P-51A) also handled superbly in its original form. While the P-51B/D later would suffer a little degradation in handling qualities the later airframe/engine combinations were still very good despite a 20% growth in gross weight.


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## Siegfried (Apr 1, 2012)

drgondog said:


> For me the best AIRFRAME was the P-51. It was the original airframe with 4 x20mm, had slightly more drag than the P-51B, and achieved excellent airspeeds with an engine operating at only 60% of its more famous successors. .



I think it would be hard to dispute this. The airframe was utterly Brilliant in terms of aerodynamic efficiency and at low altitude where its single stage single speed supercharger was not at much of a disadvantage it outran other fighters of the same power by 40mph. An interesting change occured in the transition from P-51A to P-51B was the use of internal pressure balanced ailerons that greatly alleviated pilot joystick force at speed. This made the P-51 probably the fastest rolling aircraft of the war when over 350mph (Possibly the laminar profile P-63 Kingcobra could excede it). This was only possible because the thick laminar profile wings made room for it. Latter version of the P-51D also added metalic elevators to get rid of the twitchy trim. Modified with a longer tail as the P-51H the low speed handling was considered suitable for carrier use.

The only limitation seems to have been the P-51 inabillity to handle a bigger engine like the Griffon easily.


Imagine of the P-51A had of been equiped with the Allison V-1710-121 which had a two stage supercharger from its first days of service. It really would hav shortened the war dramatically.


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## tyrodtom (Apr 1, 2012)

Again I'd rather judge by results. The Me109 may have been a little dated by 1941, by by one method or another the Germans managed to kept it close to the leading edge of performance, not at the leading edge, but close enough. Most of the other aircraft allied and axis, was a reaction to the the Me109.
And like Greg already mentioned, the results of the Me109 use in combat speak for themseves.


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## drgondog (Apr 1, 2012)

Siegfried said:


> I think it would be hard to dispute this. The airframe was utterly Brilliant in terms of aerodynamic efficiency and at low altitude where its single stage single speed supercharger was not at much of a disadvantage it outran other fighters of the same power by 40mph. An interesting change occured in the transition from P-51A to P-51B was the use of internal pressure balanced ailerons that greatly alleviated pilot joystick force at speed. This made the P-51 probably the fastest rolling aircraft of the war when over 350mph (Possibly the laminar profile P-63 Kingcobra could excede it). This was only possible because the thick laminar profile wings made room for it. Latter version of the P-51D also added metalic elevators to get rid of the twitchy trim. Modified with a longer tail as the P-51H the low speed handling was considered suitable for carrier use.
> 
> *You are correct that the the P63 (and I believe the P-39 also) could outroll the 51 at high speeds (as well as low speeds). The Iron Dog could out roll and out turn a 51 in nearly all flight profiles. You also probably recall that the P51G/J/H were complete bottom up re-designs. IIRC the P-51H had 13 common small assemblies with A/B/D*
> 
> ...



All very good points. Had the 1710-121 been available and had the US swallowed its pride and accepted the Brit 20mm cannons it would have been an incredible contributor in both MTO and PTO in 1942.. but the airframe was both extraordinary at the beginning and the internal wet wing/external wing hardpoints of the P-51A contributed much to the role/mission expansion of future dive bomber, low altitude recce, air superiortiy and CAS. Having said that there were always other fighters that could perform the same roles individually, even better.


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## tomo pauk (Apr 1, 2012)

As an airframe in combat service, think it's hard to argue against the Fw-190. The prototypes in 1941 are all another ball game, the P-51 looks like a winner.


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## jim (Apr 1, 2012)

What was the accelaration of early P-51s? Their power loading? their rate of climb? Their manouverability? What would be P51D without superior fuels given the inability to accept bigger engine?
I accept the brilliance of the design as superb escort fighter but i see shortcomings as far as air superiority fighter.
Finally i believe an important factor in the low drug of P51 was the amazing quality of its construction which of course is not a property of the airframe but of the factory that had the ability and conditions for such quality . When i saw a P51 live i was amazed by the smoothness of its surfaces.
I honestly cannot see how P51 airfame defeats Bf109F-4, or P51D defeats bf109K-4 on 1v1 combat given same quality of fuels and same building quality and same quality of pilots. Or against Ki 84, Fiat G56, Spitfire XIV, Tempest,Fw190A-3/4,etc


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## davebender (Apr 1, 2012)

I'm under the impression this topic concerns only the airframe.

Historically the 1941 Mustang and Fw-190 were handicapped by less then ideal engine choices. When these airframes received better engines they performed just fine.


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## tomo pauk (Apr 2, 2012)

Hi, Jim,

Dave is correct here - the topic is about the airframe. As you know already, with Packard Merlin installed, the P-51 transformed into a great fighter.


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## parsifal (Apr 2, 2012)

My bad, i thought it was al parts of the aircraft, other than the engine.....so things like props armament etc are considered


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## jim (Apr 2, 2012)

Mr Tomo Pauk Mr Dave bender
My point is that P 51 airframe was too heavy for the Alison and the merlin and at the same time could not recieve a bigger engine. Only superior fuels and extreme overboost ( amazing in my opinion but that s another discussion) kept it competitive at mid/low altitute and at high altitude the lack og 2 stage supercharges in german aircrafts. But these things had nothing to do with the excellence of its airframe. 
Imagine that RAF in early 42 had the P51 with the Merlin 45 in place of Spit V . What results woulde get against Bf 109F4 and Fw190 A3/4? 
I repeat P51 was excellent, top escort fighter (along late p38s) but during all its carrer i could see better dogfight/air superiority airframes,
Many german pilots had this opinion too


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## zoomar (Apr 2, 2012)

Why no love for the Spit? Was great initially, and accepted increasingly powerful engines and redesigns until the end of the war while maintaining flying qualities, something that you really can't say for the Bf-109. 

And, if we are talking only about airframe, how about the P-39? There was probably not a sleeker design in 1939, plus the tricycle gear made it a great ground handler.

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## tomo pauk (Apr 2, 2012)

I can readily agree that P-51 was not a lightest airframe, and that was somewhat restricting the rate of climb. The weight was a trade off - it was offering some 50-100% more internal fuel than other fighters with V-12 engines. The 'superior fuel' was also used in Fw-190 (the C3), so no point to draw that as an argument IMO. 
Merlins have had the supercharger sets on their side, DBs, Jumos and radials have had the swept volume (mostly) water or excess fuel injection on their. Anybody had something, making the best mix was the key for success. The basic P-51 airframe entered the fray in 1942, and as such was competitive even in 1945 - I'd say it was a great airframe. 

If any Spitfire gets bad press, that would be the Mk. V, and the year is the 1942. The P-51 of 1942 (Mustang I in RAF service) was able to fly 20-25 mph faster on the (for plenty of people) lousy Allison. The P-51A (Mustang II) was about as fast, but useful up to maybe 25000 ft (max speed achieved at 17500 ft). The Merlin 45 adds another 4000 ft to the full throttle height vs. the P-51A's engine, so the P-51 is competitive even higher up, with maybe 410 mph this time. Or we can install the Merlin XX, or 24, or 28, to add altitude flexibility.
So we have a plane that makes at least 30 mph more than Spit V, and has no problems carrying 4 cannons (as historically in Mustang Ia). I'd say it would make a good asset for any air force of 1942.
Would it be a good dogfighter? I don't know, but I know that low level Mustang Is racked up many kills vs. LW opposition, while flying for Army cooperation units. 
As an air superiority fighter? P-51s managed to fight survive in German-held airspace, even more actually.

BTW, the DB-605AS has had the the same power high up as the Merlins from 1943-44. The Bf-109 with AS engine was some 20 km/h slower than P-51 of the same era (mid 1944); P-51 was able to fly 500 miles, make it's presence felt, and return home. Unlike the 109G-6/AS (or any other).

As for different engines: after single stage V-1710, it received Packard Merlin, and a prototype was flown with two stage V-1710 (substantially longer than P. Merlin, let alone the single stage V-1710), so I see no issues there. As for Griffon as a perceived next-gen engine, the British production was small (only Spitfires were fling it war time), and there was no US production of those to make re-engining effort plausible. 
The post war racers have had the Griffon installed; it was shorter than 2-stage Merlin IIRC, so no I see no problems there.


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## davebender (Apr 2, 2012)

That's because the P-51 airframe was relatively large. IMO that aircraft was begging to be powered by a RR Griffon engine.


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## Siegfried (Apr 2, 2012)

tomo pauk said:


> . The 'superior fuel' was also used in Fw-190 (the C3), so no point to draw that as an argument IMO. .



Late war C3 was somewhere between 96/130 to 100/130 while the allied 100/130 fuel was closer to 104/130. As the Germans started ramping up C3 production, only to see it interrupted by the oil campaigns of early 1944 the allies started moving to 100/150 fuel. Early in the war C3 was closer to 94/115.

The allies maintained a substantial fuel advantage worth about 15%-20% in power. 

Very few FW 190D-9, if any ever opperated of C3 fuel. The DB605ASM engine I think was still inferior to the Merlin at altitude. The DB605ASC and ASB with their higher compression ratios however were more potent.


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## davebender (Apr 2, 2012)

> DB605ASM engine I think was still inferior to the Merlin at altitude. The DB605ASC and ASB with their higher compression ratios however were more potent.


How did the late war DB605D perform at high altitude?


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## Shortround6 (Apr 2, 2012)

zoomar said:


> Why no love for the Spit? Was great initially, and accepted increasingly powerful engines and redesigns until the end of the war while maintaining flying qualities, something that you really can't say for the Bf-109.
> 
> And, if we are talking only about airframe, how about the P-39? There was probably not a sleeker design in 1939, plus the tricycle gear made it a great ground handler.



The problem with being a sleek as the P-39 was that there wasn't enough room inside for a decent amount of fuel. It is all well and good to be the toughest guy on a small, short block but if you can't cross the street to get into the fight ( or climb above the lower floors) the title of "best" all around is out of of reach. 

Now if somebody wants to start a thread on best Fighter with under 120 gallons of fuel


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## davebender (Apr 3, 2012)

> It is all well and good to be the toughest guy on a small, short block but if you can't cross the street to get into the fight ( or climb above the lower floors) the title of "best" all around is out of of reach.


I agree.

To some extent the Spitfire and Me-109 had a similiar problem. Outstanding aerial performance but low endurance.


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## tomo pauk (Apr 3, 2012)

Siegfried said:


> Late war C3 was somewhere between 96/130 to 100/130 while the allied 100/130 fuel was closer to 104/130. As the Germans started ramping up C3 production, only to see it interrupted by the oil campaigns of early 1944 the allies started moving to 100/150 fuel. Early in the war C3 was closer to 94/115.
> 
> The allies maintained a substantial fuel advantage worth about 15%-20% in power.
> 
> Very few FW 190D-9, if any ever opperated of C3 fuel. The DB605ASM engine I think was still inferior to the Merlin at altitude. The DB605ASC and ASB with their higher compression ratios however were more potent.


 


davebender said:


> How did the late war DB605D perform at high altitude?



DB-605AS was making about the same power as Merlin 66 high up. The ASM, via usage of ADI (MW 50 here) was managing to compete at all altitudes (at SL 1800 PS, at 6400m 1500 PS). The D series have slightly more PS (maybe 50 above 5000m). Note the two values for the 2-stage DB-605L, really a great engine, but another example of 'too little, too late'.
I did not draw the 'knick' under the full throttle height (for 2nd gear) of the Merlin 66, where the 605s have advantage due to construction of it's supercharger (infinite 'number' of gears, vs. two gears of Merlin); the 'low point' of the Merlin is at some 3200m, 1450 HP. The ASM, DB and DC are far better there (only if they use the MW 50 there about, delivering some 1650-1700 HP at 3200m), but not the AS.


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## tomo pauk (Apr 3, 2012)

Shortround6 said:


> The problem with being a sleek as the P-39 was that there wasn't enough room inside for a decent amount of fuel. *It is all well and good to be the toughest guy on a small, short block but if you can't cross the street to get into the fight ( or climb above the lower floors) the title of "best" all around is out of of reach. *
> 
> Now if somebody wants to start a thread on best Fighter with under 120 gallons of fuel



Well put. Bolded part is pure gold


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## drgondog (Apr 3, 2012)

jim said:


> Mr Tomo Pauk Mr Dave bender
> My point is that P 51 airframe was too heavy for the Alison and the merlin and at the same time could not recieve a bigger engine. Only superior fuels and extreme overboost ( amazing in my opinion but that s another discussion) kept it competitive at mid/low altitute and at high altitude the lack og 2 stage supercharges in german aircrafts. But these things had nothing to do with the excellence of its airframe.
> 
> *It is an interesting argument to start by assigning 'too heavy' to the P-51 Airframe. We might consider the relative weights of the F-22 versus MiG 29, F-15 and ask the same question. Or compare the heavy P-51 to the F4U or P-47 or P-38?
> ...



I wonder which airframes the German pilots had in mind as better air superiority airframes? The ultimate questions dwindle down to 'point superiority-short leash' airframes for interception and 'long distance air superiority-long leash' for dominance over the enemy's airspace. For the latter your choices kind of narrow down to A6M, F6F, F4U, P-47 and P-38 for initial selection - and pass over Bf 110 and all LW/VVS/GB fighter derivatives?

If the Bf 109 and FW 190 are point superiority, defined as over your own airspace and say 200 miles into enemy airspace, the next question is did they achieve air superiority against the heavier, longer range aircraft cited above? Were they able to achieve 'break even results' when the odds were reasonably equal over their home airspace?

How did lower gross weight affect the outcome?


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## davparlr (Apr 3, 2012)

jim said:


> What was the accelaration of early P-51s? Their power loading?


Remember it is not horsepower to weight that determines acceleration but rather available horsepower to weight. Take for instance a P-51 (Allison) and a Bf-109F flying at SL at 325 mph. The power loading is in favor of the Bf-109F because it is lighter and both engines are capable of about 1150 hp. However, the max speed of the Bf-109F at SL is 325 mph while the P-51 max speed is 344 mph. At 325 the lighter Bf-109F is expending all of its power just to maintain airspeed and has zero available to accelerate. The heavier P-51, however is not expending all of it power to maintain airspeed and has hp available to accelerate to 344 mph. So at every airspeed, the Bf-109F is expending more engine power just to maintain airspeed than the P-51 which will have more available hp. Will this always mean the P-51 will out accelerate the Bf-109F at every airspeed, I don’t think so, but you need to know the using hp at the desired airspeed to determine acceleration issues. The P-51 will certainly out accelerate the Bf-109F at 325 mph!

Some stats
Bf-109F *1150 hp* *324 mph* at SL
Fw-190A-3 *1730 hp* *335* mph at SL
Spit II *1090 hp* *290 mph* at SL
P-51 (Allison) *1150 hp* *344 mph* at SL

An excellent example of airframe efficiency.



> their rate of climb? Their manouverability?


In 1944, the P-51B with 300 less hp is equivalent to the vaunted Fw-190D-9 in airspeed and climb up to 20k where it then just out performs the D-9. The slightly heavier P-51D is close behind.



> What would be P51D without superior fuels given the inability to accept bigger engine?


This seems to be a strange comment. Where would the Bf-109 be without MW-50. The P-51 did not use water injection until the P-51H came along. By the way, the dash 9 engine in the P-51H with water generated over 2200 hp, which is quite favorably compared to the Spit XIV, Tempest, and any Fw-190, even the D-9. The Merlin engine was three hundred pounds lighter than the Griffon, seven hundred pounds lighter than the Napier, and four hundred pound less than the Jumo 213.



> I accept the brilliance of the design as superb escort fighter



Typically not debatable



> but i see shortcomings as far as air superiority fighter. I honestly cannot see how P51 airfame defeats Bf109F-4


The F-4 was significantly outclassed in airspeed (50 mph at SL) and matched in climb by the P-51B pulling 67” Hg. And, apparently debatably it would out turn the Bf.



> , or P51D defeats bf109K-4 on 1v1 combat given same quality of fuels and same building quality and same quality of pilots.


This is a different story. The K was a high performance point intercepter and was a formidable opponent to the B or D, but it had limited endurance.



> Or against Ki 84, Fiat G56, Spitfire XIV, Tempest,Fw190A-3/4,etc



None of these planes could fly the distance the P-51 did except for the Ki-84 which was not as fast. The G56 was way too slow. Speed is energy, energy is life not maneuverability.



> My point is that P 51 airframe was too heavy for the Alison and the merlin and at the same time could not recieve a bigger engine.


Did anyone try?


> Only superior fuels and extreme overboost ( amazing in my opinion but that s another discussion) kept it competitive at mid/low altitute and at high altitude the lack og 2 stage supercharges in german aircrafts. But these things had nothing to do with the excellence of its airframe.



The P-51 was a superbly designed airframe.



> Imagine that RAF in early 42 had the P51 with the Merlin 45 in place of Spit V . What results woulde get against Bf 109F4 and Fw190 A3/4?



For one thing it would have been 30 mph faster than any of them and control when and where to fight and could loiter much longer and chase the enemy all the way home.



> I repeat P51 was excellent, top escort fighter (along late p38s) but during all its carrer i could see better dogfight/air superiority airframes,


Yes but they weren’t needed do to range and the P-51 was and could out fly the enemy over its own territory.



> Many german pilots had this opinion too


P-51 pilot experts testify just to the opposite.


_View: https://www.youtube.com/watch?v=aB6ka32iTbU_

Surprise, surprise.


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## davebender (Apr 3, 2012)

The P-51B and P-51D had extreme range to meet a requirement unique to the U.S. Army Air Force. Other nations aren't going to build such a flying fuel tank if it isn't needed. Just as the U.S.A.A.F. wasn't going to arm and armor the P-51 for shooting down hordes of enemy bombers without a need to do so.


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## tomo pauk (Apr 3, 2012)

Japanese planes have had the extreme range cašabilities, from beginning of the ww2. RAF was trying to increase ranges of their Spitfires, 1st by installing 29 imp gal fuel rear tank, later going to the circa 70 gals. Spitfire from 1942 was able to fly with a dropable 175 imp gals fuel tank - about as much as Merlin Mustangs had under wings with 2 x 108 us gals. Soviets were trying to boost the range of their Yaks, 1st with Yak-9D ('distantsnoy' - literary 'for distances'), later with Yak-9DD ('dalyno distantsnoy' - for great distances), so they saw need for great combat ranges, too. Ta-152 was to feature wing root tanks, Bf-109H too.

IMO the Japanese were 1st to foresaw the need for fighters with legs, no wonder since the vast areas of Asia/Pacific were to be the hunting area for those.


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## Shortround6 (Apr 3, 2012)

The initial P-51 wasn't really a flying fuel tank. Especially compared to other US fighters. 180 US gallons in protected wing tanks is actually fairly normal for a US fighter if looked at historically. Given the size of the US we needed longer ranged fighters just to move around the country on deployment let alone combat missions. 

The P-36 carried 155-160 gallons in unprotected tanks in 1938. The P-40 carried about the same and went for as much as 200 in unprotected tanks before the self-sealing tanks were adopted. The early P-38s carried 400 gallons. 
The P-51 just allowed the carriage of the "normal" desired fuel capacity in protected tanks. 
The other part of the greater range came from the low drag airframe, much like a 109F has a longer range than a 109E using the same amount of fuel or the much ballyhooed He 100 had such a long range on the same amount of fuel as the 109E. 

Since this thread is about the BEST AIRFRAME, the adaptability of the airframe needs to be considered. The P-51 not only had the range thing going for it, it had the ability to be armed as a bomber destroyer if that was what was wanted. It also had the ability to be used as a fair fighter bomber with a much higher payload ( especially considering the radius it carry the bombs over) than many of the other planes.


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## parsifal (Apr 3, 2012)

Yes, the RAF would have loved to have a P-51 or equivalent in 1942, to extend the air superiority they had already gained (at such hig price) over Britain, the Channel and the channel coast in 1941-2. The Luftwaffe either refused battle except under the most favourable circumstances, or withdrew out of the range of FC. If FC had had a long range fighter like the P-51 in 1942, they could have finished the LW off in the west.

In 1943 when the P-51 began to be supplied as LL, the RAF could not get enough of them. There were no serious complaints about the type from any in the CW that used them.

What we are seeing here is the classic formula these guys always use....mix a little truth with a load of codswallop to jazz up the brew, and thereby increase its potency. that way more people will believe the basic lie


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## drgondog (Apr 3, 2012)

Parsifal - have you thought about the effect you have on tender ears when you 'tippy toe' around the point?


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## davebender (Apr 3, 2012)

That was a naval requirement. The IJN needed a long range escort for long range Nell and Betty maritime attack aircraft.


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## pbfoot (Apr 3, 2012)

IMHO you have to be on drugs if you think that Fighter Command won the Channel War 42 -43. I do believe who ever believes that the Channel War was a done thing or allied victory is few pages short of a book.


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## drgondog (Apr 3, 2012)

davebender said:


> The P-51B and P-51D had extreme range to meet a requirement unique to the U.S. Army Air Force. Other nations aren't going to build such a flying fuel tank if it isn't needed. Just as the U.S.A.A.F. wasn't going to arm and armor the P-51 for shooting down hordes of enemy bombers without a need to do so.



Dave - it would be better to stipulate "US" because the USN certainly had long range requirements to extend escorted bomber footprint from carriers.

The USAAF contemplated the P-38 with 1x20 and 4x50 as more than enough for interceptor work and certainly had 4x20 to fall back on for bomber interceptor role - ditto P-47 8x50s as well as F6F and F4U standard and optional armament. The P-51B w/4x50 was a little light for He 177 and Do 217 but didn't have too much trouble taking them down one on one. Other than the 'horde' issue the US was well prepared to take on LW/Japanese/Italian bombers throughout the war until the Ar234.

The P-51B was just as formidable to the Do 217 as the 109 was to the B-17. I wouldn't make that claim versus the FW 190!


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## tomo pauk (Apr 3, 2012)

Betty and Nell were not designated as 'maritime attack aircraft' in IJA, but as the 'heavy bombers', able equally to carry bombs or torpedo, to attack both ground maritime targets. The Zero was to be able equally to escort those and Bettys and Vals. The Japanese seem to not believe in the maxims that bombers could protect themselves, nor that they will always get through, at least not in early ww2 years.


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## jim (Apr 3, 2012)

parsifal said:


> Yes, the RAF would have loved to have a P-51 or equivalent in 1942, to extend the air superiority they had already gained (at such hig price) over Britain, the Channel and the channel coast in 1941-2. The Luftwaffe either refused battle except under the most favourable circumstances, or withdrew out of the range of FC. If FC had had a long range fighter like the P-51 in 1942, they could have finished the LW off in the west.
> 
> In 1943 when the P-51 began to be supplied as LL, the RAF could not get enough of them. There were no serious complaints about the type from any in the CW that used them.
> 
> What we are seeing here is the classic formula these guys always use....mix a little truth with a load of codswallop to jazz up the brew, and thereby increase its potency. that way more people will believe the basic lie



Like channel dash? 
Like Dieppe? Luftwafffe ordered the british where to land ? And then then run away ? Who shot down 120 british plsnes? Even if i used a little truth you used none.
Parsifal 
The quality of historical accarancy and truth of your post is analog to your quality. Call me leier by the safety of your chair.Keep exchange likes with drgondog
Drgondog , nice irony your last post
Mr Dave parir
a) MW50 was nothing special, 150 octane fuel was special 
b) Ki84 why was not fast? 2000hp in a relatively small airframe
C) P51A accelarated very slowly to its top speed. It is reported in this forum
d)F4 is 41/42 machine
e) G56 was 685-700 km/h machine
Anyway, opposite opinion means leis for the anglosaxons. Time to retire.


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## Siegfried (Apr 3, 2012)

davebender said:


> How did the late war DB605D perform at high altitude?



The DCM and DBM (M if MW50) the D engines had a higher compression ratio than the DB605ASM so *for the same manifold pressure had higher power and efficieny.*. In addition the engine could take 1.8 even 1.98 ata boost. 

Some tables here, of limited use due to the lack of full curves.
The Luftwaffe page , Daimler-Benz DB 605

The rated aktitutenpower at rated altutue for DB and DC would apply for the DC and DB rate altitude. 
There was the DB605L engine with a two stage supercharger, however the single stage DB605DCM series did quite well.

IE the power levels for D2, DB, DC would apply to all 3


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## davebender (Apr 3, 2012)

They also had 3 valves per cylinder rather then 4 like DB605A series engines. Not sure why they made that change.


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## pinsog (Apr 3, 2012)

I repeat P51 was excellent, top escort fighter (along late p38s) but during all its carrer i could see better dogfight/air superiority airframes,
Many german pilots had this opinion too[/QUOTE]

I'm sorry, but I get an image of some poor hapless German pilot running like mad with a Mustang hot on his tail, 50 caliber tracer rounds pelting his airframe and then 1 minute later, he is floating down in his parachute thinking about what a pile of junk it was that just shot him down. 

How could German pilots have anything but the GREATEST respect for an airplane that flies all the way from Britain, shoots your top performing fighters down in flames on a regular basis and then flies home.

PS: I don;t even like the Mustang. I like the P47 and the F4U


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## parsifal (Apr 3, 2012)

> Parsifal - have you thought about the effect you have on tender ears when you 'tippy toe' around the point?


I think thats why they like me so much


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## parsifal (Apr 3, 2012)

> Like channel dash?


Made necessary by the repeated unansweerd attacks on the heavy ships based in the channel. If the allies did not posses air superiority the channel dash (a retreat made out by the german propaganda machine to look like a victory) would never have been needed 



> Like Dieppe? Luftwafffe ordered the british where to land ? And then then run away ? Who shot down 120 british plsnes? Even if i used a little truth you used none.



The fact that the british could undertake a cross channel raid in 1942 is evidence of itself that they had won air superiority. without air superiority the operation could not be undertaken. This was precisely the reason the Germans could not undertake such raids at any time, from1940 on. They never gained air superiority, ergo they could not undertake military action with complete freedom of manouvre.

air superiority is not about losses. In my posts I acknowledge that the British won their prize at great cost. Air superiority is not about having the flashiest fighters, its about getting control of the sky and being able to do the things you want to do. In 1942 the allies had greater fredom of action compared to the LW. Germans still had air denial capability, hence the losses, but this was a wasting asset, a pointless, directionless resistance that was leading them nowhere. The allies were working toward a goal and achieving it.

The losses at Dieppe are not as one sided as you suggest, but I will leave that to others to explain to you. Suffice it to say that it was evidence of the german ability to deny airspece. the allied evidence of air superiority was in their ability to undertake the operation in the first place, confident that the LW could not stop them 




> Parsifal
> The quality of historical accarancy and truth of your post is analog to your quality. Call me leier by the safety of your chair.Keep exchange likes with drgondog



I didnt call you a liar, I said this is the brew used by some to increase the potency of the brew. if you think you have told lies in your post, good on you for admitting as much.

I like DGs posts because he provides crystal clear clarity and brings a lot of knowledge into this place. That deserves respect ("like) in my opnion 



> Anyway, opposite opinion means leis for the anglosaxons. Time to retire.



Im not an anglo saxon, and yes, it might be time to retire. bye bye until next time


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## davebender (Apr 3, 2012)

21 May 1944. 
Erich Hartmann flying Me-109G near Bucharest.
Hartmann shot down two P-51s without difficulty then evaded the other 8 P-51s until his Me-109G ran out of fuel, forcing him to bail out.

IMO this engagement nicely sums up the strengths and weaknesses of Me-109s vs P-51s. The Me-109 sacrificed internal fuel capacity to achieve an excellent power to weight ratio resulting in superior aerial performance. Just hope the battle doesn't last long or take place far from your airfield.


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## DonL (Apr 3, 2012)

> The fact that the british could undertake a cross channel raid in 1942 is evidence of itself that they had won air superiority. without air superiority the operation could not be undertaken.



With all respect, Dieppe was nothing more then a suicide commando what ended in a total disaster. I can't understand, with any military thinking, that Dieppe proved anything except it was a wrong plan at a wrong time. 

*Any suicide commando can be undertaken at any time!*

At 1942 the FW 190A was introduced in numbers at the english channel and was called the butcher bird by the english counterparts and the FC had a very difficult time near the whole year 1942 to get something equal in the air. To all my books nobody had ever claimed a FC air superiority at 1942 of the english channel.

Sorry here I disagree fundamental from military viewpoint!

Edit:



> The losses at Dieppe are not as one sided as you suggest, but I will leave that to others to explain to you. Suffice it to say that it was evidence of the german ability to deny airspece. the allied evidence of air superiority was in their ability to undertake the operation in the first place, confident that the LW could not stop them



The allied losses were 4359 men (1179 killed and 2190 prisoners, rest injured). The FC lost 119 fighters. 
The Wehrmacht lost 311 men and 280 injured. The LW lost 29 fighters and total 74 aircrafts (40 bombers). From this 74 aircrafts were 48 total losses.

If this isn't one sided, what is in your opinion one sided?


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## pinsog (Apr 3, 2012)

davebender said:


> 21 May 1944.
> Erich Hartmann flying Me-109G near Bucharest.
> Hartmann shot down two P-51s without difficulty then evaded the other 8 P-51s until his Me-109G ran out of fuel, forcing him to bail out.
> 
> ...


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## michaelmaltby (Apr 3, 2012)

".... With all respect, Dieppe was nothing more then a suicide commando what ended in a total disaster. I can't understand ...."

Careful, my friend. We don't describe Dieppe quite that way in Canada. We acknowledge that Dieppe was ill-fated, and we admit there were 'political' considerations - of our own making - here in Canada - but Dieppe was not suicidal. Canadian Forces don't roll that way, and if you know your history - both wars - you should know that, DonL.

MM


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## DonL (Apr 3, 2012)

For me, from a strictly military viewpont, this whole raid was suicidal!

There was know single hope or chance that this raid would be in any kind successful and this was communicated to Lord Mountbatten more then one time!

Edit:

I have no problem to describe german military actions as suicidal, if they had the same chance of success as Dieppe!
For exampel, Stalingrad was at a certain date nothing more then suicidal!


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## davebender (Apr 3, 2012)

Operation Jubilee order of battle - Wikipedia, the free encyclopedia
4th Canadian Infantry Bde (3 regiments)
1 infantry company plus a mortar platoon from 5th Canadian Infantry Bde.
6th Canadian Infantry Bde (-). 1 regiment did not go ashore.
14th Tank Regiment.

Did the Canadian division size task force withdraw any equipment from the beach?


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## parsifal (Apr 3, 2012)

> With all respect, Dieppe was nothing more then a suicide commando what ended in a total disaster. I can't understand, with any military thinking, that Dieppe proved anything except it was a wrong plan at a wrong time.
> 
> *Any suicide commando can be undertaken at any time!*


*

It was not seen as a commando attack and whilst it proved suicidal, its purpose was partly to act as a sop to Stalin and demonstrate to him that a cross channel attack impractical. Sacrificing 5000 Allied lives (mostly Canadian) saved tens of thousands of others. It proved that a direct attack onto a defended port or coast was indeed suicide, and led to a whole range of changes to amphibious assaults that followed. most notably a massive increase in gunfire support, the allocation of specific direct fire support ships (usually DDs) that acted as a rapid response unit for individual formations on shore (usually of battalion size). This experience, and that gained during the TORCH landings greatly reduced the casualty rates in the larger operations that followed, such as GHusky, Neptune/Overlord and Dragoon. The techniques learnt at Dieppe were even of benefit to the fighting in the Pacific.

Dieppe was never intended or executed as a permanent landing. it was always a probing attack, to test defences and learn fom the experience. in this regard it was an outstanding success. it achieved the strategic aims it was designed to do, but at great cost. 




At 1942 the FW 190A was introduced in numbers at the english channel and was called the butcher bird by the english counterparts and the FC had a very difficult time near the whole year 1942 to get something equal in the air. To all my books nobody had ever claimed a FC air superiority at 1942 of the english channel.

Click to expand...


Im not claiming the LW was driven from the sky, or that they were not capable of inflicting heavy losses. But look up what the meaning of air superiority is. The Germans didnt have it, not in 1940, not in 1941, certainly not in 1942. The British didnt have it in 1940, many claim that they had achieved it by 1941, but more say by 1942. 

Air superiority has little to do with losses. It has mostly to do with control....what can be done and what cannot. Amphibious asault is generally seen as impossible if the enemy holds air superiority. It can be undertaken if the air control state is neutral, but its best to have control of the air to maximise success of the operation. Thats one of the main reasons why the japanese did not undertake any further amphibs after August 1942, and why the germans did not undertake any amphibs except in the baltic, after 1940 (and in the baltic they were unsuccessful in 1944, though they did succeed in '41) 




Sorry here I disagree fundamental from military viewpoint!

Click to expand...


Thats fine, we have disagreed on this point before, but military theory is military theory, and the definition of what constitutes air superiority is also very clear. I am simply applying the theory to the situation on the western front (the british isles, the Channel and the European Channel Coast). The allies had achieved air superiority ion either 1941, or 1942, within those parameters. Thats not my opinion, or some far out position, its the simple application of what is air superiority to that region. 




The allied losses were 4359 men (1179 killed and 2190 prisoners, rest injured). The FC lost 119 fighters. 
The Wehrmacht lost 311 men and 280 injured. The LW lost 29 fighters and total 74 aircrafts (40 bombers). From this 74 aircrafts were 48 total losses.

If this isn't one sided, what is in your opinion one sided

Click to expand...

?

I was mostly referring to the air losses, but in the context of what the operation set out to do, and what it did achieve, it was successful. it was never going to be cheap, but what it achieved saved more lives than it cost.

Military success is not always the butchers bill. in fact it seldom is. The casualty figures are a by-product of the operation. Look at Lees defences in the seven days battles during the ACW and you will see what im referring to. Now, the casualties for Dieppe are undenaible, but what did it achieve ? For the germans, virtually nothing, for the allies, a welath of information, and a soothing of a disgruntled ally. Good value at the price paid IMO*


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## michaelmaltby (Apr 3, 2012)

"... Did the Canadian division size task force withdraw any equipment from the beach?"

I don't believe so, db. The main stuff was the Churchills and they didn't get off the pebble-cobblestone beach - sadly.


"... I have no problem to describe german military actions as suicidal, if they had the same chance of success as Dieppe!
For example, " Stalingrad" was at a certain date nothing more then suicidal!

Doomed perhaps. Certainly doomed. But suicidal no. Hitler was suicidal, but the Germans in the kettle were NOT suicidal and, DonL, you speak too glibly about the lives of your dead countrymen, IMHO . "Suicidal", indeed !!!!


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## DonL (Apr 3, 2012)

> It was not seen as a commando attack and whilst it proved suicidal, its purpose was partly to act as a sop to Stalin and demonstrate to him that a cross channel attack impractical. Sacrificing 5000 Allied lives (mostly Canadian) saved tens of thousands of others. It proved that a direct attack onto a defended port or coast was indeed suicide, and led to a whole range of changes to amphibious assaults that followed. most notably a massive increase in gunfire support, the allocation of specific direct fire support ships (usually DDs) that acted as a rapid response unit for individual formations on shore (usually of battalion size). This experience, and that gained during the TORCH landings greatly reduced the casualty rates in the larger operations that followed, such as GHusky, Neptune/Overlord and Dragoon. The techniques learnt at Dieppe were even of benefit to the fighting in the Pacific.
> 
> Dieppe was never intended or executed as a permanent landing. it was always a probing attack, to test defences and learn fom the experience. in this regard it was an outstanding success. it achieved the strategic aims it was designed to do, but at great cost.



I have great doubts that from 4.50 AM to 10.50 AM at one day so much can be learned! I have no doubt that there were some interesting informations but I have a major problem that you sell the operation as great success from the learning viewpoint!
There were more then one chances to achieve such a learning experience under much better conditions and as I said I have my doubts that that much can be learned in six hours of fighting and reaction. Do you have primary sources for this claim?

Also I think that all other landings had a much more learning experience then Dieppe, because nothing of the original plan was achieved, and Dieppe proved that the allied had *not* the military freedom to initiate such a military action, because they hadn't the air superiority and the whole plan ended in a disaster!



> Im not claiming the LW was driven from the sky, or that they were not capable of inflicting heavy losses. But look up what the meaning of air superiority is. The Germans didnt have it, not in 1940, not in 1941, certainly not in 1942. The British didnt have it in 1940, many claim that they had achieved it by 1941, but more say by 1942.



To all my books all said at 1941 and 1942 it was equal, so who claimed the FC air superiority at the english channel at 1942?



> Air superiority has little to do with losses. It has mostly to do with control....what can be done and what cannot. Amphibious asault is generally seen as impossible if the enemy holds air superiority. It can be undertaken if the air control state is neutral, but its best to have control of the air to maximise success of the operation. Thats one of the main reasons why the japanese did not undertake any further amphibs after August 1942, and why the germans did not undertake any amphibs except in the baltic, after 1940 (and in the baltic they were unsuccessful in 1944, though they did succeed in '41)



To come back to this, for me Crete was also a partly a amphib landing and at this time, to me, the german LW had air superiority and the landing of Crete was a success with very heavy losses but the FC was miles away from this air superriority at 1942 at the english channel, so Dieppe was a full disaster. 



> I was mostly referring to the air losses, but in the context of what the operation set out to do, and what it did achieve, it was successful. it was never going to be cheap, but what it achieved saved more lives than it cost.



As I said I have my doubts because I think the other operations did a lot more from the learning viewpoint to the allied then Dieppe! 



> Doomed perhaps. Certainly doomed. But suicidal no. Hitler was suicidal, but the Germans in the kettle were NOT suicidal and, DonL, you speak too glibly about the lives of your dead countrymen, IMHO . "Suicidal", indeed !!!!



Perhaps we have here a misunderstanding! I have *not* and would *not* ever say that the soldiers or the local commanders were suicidal, because most or all of them didn't knew the whole or parts of the plan and the action and most important not the capacity of the enemy.

But the persons who have fielded the plan of Dieppe knew the risks and the capacity of the enemy and at any serious military there are sand pit games and success estimations of an action. 
So either the estimations were totaly/absolutely wrong or the soldiers lifes were totaly equal to the "important" people!
To me, if a military action is estimated as heavy failure from the beginning, but is initiated nevertheless, it is suicidal!


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## FLYBOYJ (Apr 3, 2012)

Gents, good conversation and information but let's try to get this back on topic.


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## parsifal (Apr 3, 2012)

The best on-line definition on what constitutes air superiority 9as opposed to air parity, air denial or air supremacy) can be found at the following link.

Go to chapter 1, it gives a pretty good rundown on what air superiority is, and why the allies could claim it from 1941-2. The germans cannot. They can claim an air denial state, but they lacked the freedom that comes with air superiority to undertake a whole range of operations on the western front. That culminated with the Channel Dash, but the germans could never have undertaken a Dieppe. They lacked the air superiority to do that.

Anyway, here is the link. might be of help 

The Air Campaign: Planning for Combat


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## parsifal (Apr 3, 2012)

In any event, and an attempt to get this back on topic, the claim that led to this fraccus was that the P-51 was not a very good airframe, or at least not better than any of its contemporaries. Debateable. then the claim was what would happen if the RAF had possessed an aircraft like the P-51 in 1942. To which my reply was...they would finish the job they started in 1941 a whole lot earlier.

This has raised clouds of dust from here to Berlin it seems. But I remain of the opinion that an aircraft like the P-51 in the hands of the RAF in 1941 would have had the same effect as it did in American hands in 1944. Nowhere safe for the LW to run and hide, so safe skies for them to train, an aircraft equal or superior to the very best they (the Germans could field at any time in the war. a war winner of strategic importance. 

nothing in the foregoing discussions, with all its smokescreens and cabal sways me to an alternative view

For those wanting to learn a little more about the dieppe raid, i recommend the following link

http://www.combinedops.com/Dieppe.htm


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## DonL (Apr 4, 2012)

> In any event, and an attempt to get this back on topic, the claim that led to this fraccus was that the P-51 was not a very good airframe, or at least not better than any of its contemporaries. Debateable. then the claim was what would happen if the RAF had possessed an aircraft like the P-51 in 1942. To which my reply was...they would finish the job they started in 1941 a whole lot earlier.
> 
> This has raised clouds of dust from here to Berlin it seems. But I remain of the opinion that an aircraft like the P-51 in the hands of the RAF in 1941 would have had the same effect as it did in American hands in 1944. Nowhere safe for the LW to run and hide, so safe skies for them to train, an aircraft equal or superior to the very best they (the Germans could field at any time in the war. a war winner of strategic importance.



Under which definitions?

With an Allison single stage engine or a Rolls-Royce Merlin 45 ( Spitfire MK V engine) I have my doubts to this claim!
I see no advantage of such a P51 compare to the FW 190A, Bf 109F or Spitfire. Range isn't all if the counter aircrafts are better.
The Spitfire MK V had it's difficult troubles against the FW 190A and the Bf 109F and the P51 would be a lot more heavier then the Spitfire.

There would perhaps interactions at other frontlines (UDSSR, North Africa etc...), but the LW would react to such an aircraft, perhaps with one more JG at France from an other frontline. You can't do such a claim without the engine of the airframe and the estimated performance!

Edit:

You can't divide the airframe from the engines of the timeline!
For example a Tank 152 H or C, or a Fw 190D-9 would do nothing to the LW with a DB 601E, any Bf 109F or FW 190A would perform better.

I don't deny the claim of the airframe of the P51, but a certain airframe needs a proper engine to play all it's good parts, if the engine had not enough performance for the airframe, the aircraft will be outperformed from other aircrafts, where the airframe and engine match better.


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## Juha (Apr 4, 2012)

davebender said:


> 21 May 1944.
> Erich Hartmann flying Me-109G near Bucharest.
> Hartmann shot down two P-51s without difficulty then evaded the other 8 P-51s until his Me-109G ran out of fuel, forcing him to bail out.
> 
> IMO this engagement nicely sums up the strengths and weaknesses of Me-109s vs P-51s. The Me-109 sacrificed internal fuel capacity to achieve an excellent power to weight ratio resulting in superior aerial performance. Just hope the battle doesn't last long or take place far from your airfield.



Hello Dave
Sorry to say, but on 21 May 44, there was no USAAF raids around that area, no Hartmann' P-51 claims and no 15th AF Mustang losses, so it is no use to make any conclusions on that story.

Juha


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## parsifal (Apr 4, 2012)

The japanese proved what range could do for an air force. For the defender it would be devastating, and by the latter half of 1941, the germans were almost exclusively on the defensive on the western front. That had implications as suggested in Gallands book.

By giving the british range AND the initiative, the LW would be conceding an awful lot. A lot more than what just one JG could achieve. Instead of 2 Gp and the 18 or so squadrons of FC that were committed to the campaign (at the start....it gradually increased as time went by) being restricted to attacks up to about 120 miles from the british coast, attacks with escort could have been mounted virtually anywhere in the Reich. at miniimum that means that one of the two JGs based on the Coast would have to decentralise, and even then, full coverage could not be provided. Bombers attacking by day, untroubled by any defensive fighters are a significant menace. The RAF by March '42 already had the ability to put 1000 bombers over the target by night. And in '42 those raids were starting to bite deep, culminating in Hamburg a year later, easily the worst raid prior to 1945. And these raids were at night, with the constant fear of NJGs and the inherent navigational issues affecting accuracy. how much more devastating if the raids were unintercepted, and conducted by day. It alters the equation of the strategic offensive enormously. In fact there is every reason to support the notion that LW would be forced to pull back 80-90% of their available fighters for reich defences in '42, exactly as they were forced to do in '44 when the US began its deep penetration escorted raids.

Whilst I agree that engine development does affect the realization of the airframes full potential, arguing that an aircraft with similar performance as the Spit V but with massive range could not provide effective escort is silly in my opinion. The German types of 1941-2 were generally superior to the SpitV, but not by that much as to say Merlin 45 equipped Mustang could not provide effective escort. Dont know about the allison, because i dont know about the engine really. But i am confident that if the Mustang of 1942 had been equipped with the earlier version of the merlin, it still would have been quite capable as a long range escort. If necessary expedients could have been adopted like reducing the armament, or the amount of armour,which could have lifted or retained adequate performance, though i doubt such expedients would be necessary. Once you get to that point the LW is in a world of hurt.


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## Jabberwocky (Apr 4, 2012)

With a similar engine to a P-40 or Spitfire, the Mustang was anywhere from 20 to 40 mph faster at any given altitude. That speaks greatly to the aerodynamic efficiency of the aircraft and presents a major advantage for the Mustang. 

For example, the V-1710 P-40E would do about 310-320 mph at sea level. The P-51 with the same power would do 345-355 mph. 

A Merlin 61 powered Spitfire Mk IX would do 330 mph at sea level, 4040408 mph at 25,500 feet. A V-1650-3 powered P-51B would do 350-355 mph at sea level and 440-445 mph at 25,000 feet.

A V-1650-1 powered P-40F would do 360-365 mph at 18,000-21,000 ft. With roughly the same power, the (slightly more aerodynamic) Allison powered P-51s were getting to 395-405 mph at about 17,000 ft in 1942. 

That puts a V-1650-1 powered P-51 firmly into the 400 mph + category aircraft above 20,000 ft. And that's a huge advantage.

The P-51 was not only a fast aircraft, but a very good pilots aircraft. It was light on the controls, accurate in response and had very few bad habits. It possessed better manoeuvrability (roll, rate of pitch, turning circle) than the slightly lighter P-40. The Mustang might lose out to a Spitfire in overall manoeuvrability, but its better than anything else the RAF and USAAF could field. 

A US review of the British experience with the P-51/P-51A after 18 months of combat found:

“It has been found that the Mustang is faster than the ME-109 and the FW-190, and that 4000 to 8000 is a good altitude at which to catch the enemy. At sea level, the Mustang can run away from any enemy aircraft they have encountered to date. The pilots are schooled to run rather than fight because their main objective is the destruction of ground targets, not to fight enemy aircraft. They are instructed in the use of flaps in combat to reduce their turning radius (which with flaps is shorter than the ME-109 or FW-190). At least one FW-190 has been made to spin in through the use of a small amount of flap by the Mustang when engaged in a turning contest at low altitude; the FW-190 tried to tighten his turn to keep the Mustang in his sights after the pilot had dropped his flaps slightly but spun out of the turn.”

AND

“Actual combat has proven that the aircraft can run away from anything the Germans have. It’s only inferior points are that it can’t climb as well as the ME-109 and FW-190 and that at the slower speeds of close combat it loses effectiveness of aileron control and therefore has a poor rate of roll – but its turning radius with a slight amount of flap is shorter than either of the German aircraft.”


A hypothetical Merlin 45/V-1650-1 (1240 hp) powered P-51 would probably have a speed, roll rate (at high speed), high speed controllability and dive advantage over a Spitfire V and (under 25000 ft) against a 109F2/4, but a disadvantage in rate of climb, turning circle and low speed acceleration and roll.

Against a 190A-2/3/4, it would have a turn advantage and maybe speed advantage at higher altitudes. It would lose out in performance under 20,000 ft, rate of acceleration, rate of roll and rate of climb, particularly at lower altitudes.


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## wuzak (Apr 4, 2012)

Jabberwocky,

I would like to pint out that the V-1650-1 wasn't a Merlin 45, but rather a Merlin 20 series (equivalent to a 23 IIRC). 

A P-51 fitted with a Merlin 45 would most likely be slower than a P-51A below the rated altitude of the V-1710 (about 12,000ft IIRC), and probably not be any faster until near the Merlin 45's rated altitude (c. 18,000ft), but above that it woul ddefinitely be faster.

The 45 was a single speed-single stage supercharged engine, the V-1650-1 a 2 speed single stage engine.


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## wuzak (Apr 4, 2012)

Jabberwocky said:


> A Merlin 61 powered Spitfire Mk IX would do 330 mph at sea level, 4040408 mph at 25,500 feet. A V-1650-3 powered P-51B would do 350-355 mph at sea level and 440-445 mph at 25,000 feet.



I have seen perfomance numbers for the Spitfire IX as much as 417mph but, WOW, 4040408mph!

Time must slow down for the pilot!


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## riacrato (Apr 4, 2012)

tomo pauk said:


> As an airframe in combat service, think it's hard to argue against the Fw-190. The prototypes in 1941 are all another ball game, the P-51 looks like a winner.


This. As an airframe in service the Fw 190 was performing well and had plenty of development potential, being able to take up heavier engines, heavy armament, more equipment and more fuel while remaining relatively clean and having enough of a margin not to deteriorate handling too much.

The prototype P-51 was exceptionally clean and well designed without taking too many risks (e. g. evaporative cooling) or being too complex to build economically. As such it was the apex of piston engine airframe development. I don't see why it shouldn't be able to take up an engine in the class of the Griffon or DB603, it just wasn't necessary.

The Typhoon should also get a mention of some kind. While I think the airframe was not as sound as the above two from the beginning, it evolved into the very good Tempest and Fury.
Also, weren't Yak 3 prototypes around in 1941? Would also make for an interesting choice.


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## Cola (Apr 4, 2012)

Shortround6 said:


> Since this thread is about the BEST AIRFRAME...


 
No such thing.
(btw, why "1941" in the title of the thread?)



pinsog said:


> I repeat P51 was excellent, top escort fighter (along late p38s) but during all its carrer i could see better dogfight/air superiority airframes,
> Many german pilots had this opinion too




_View: https://www.youtube.com/watch?v=TFl8X4y9-94_

_View: https://www.youtube.com/watch?v=b69pO7538sE_


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## DerAdlerIstGelandet (Apr 4, 2012)

Cola said:


> (btw, why "1941" in the title of the thread?)



Why? Because he is asking about the airframes in use in 1941...


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## Milosh (Apr 4, 2012)

wuzak said:


> Jabberwocky,
> 
> I would like to pint out that the V-1650-1 wasn't a Merlin 45, but rather a Merlin 20 series (equivalent to a 23 IIRC).
> 
> ...



Depending on which airplane it was mounted in the V-1650-1 could be a 28 or a 29 or a 31 or a 33 or a 38.


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## DonL (Apr 4, 2012)

> By giving the british range AND the initiative, the LW would be conceding an awful lot. A lot more than what just one JG could achieve. Instead of 2 Gp and the 18 or so squadrons of FC that were committed to the campaign (at the start....it gradually increased as time went by) being restricted to attacks up to about 120 miles from the british coast, attacks with escort could have been mounted virtually anywhere in the Reich. at miniimum that means that one of the two JGs based on the Coast would have to decentralise, and even then, full coverage could not be provided. Bombers attacking by day, untroubled by any defensive fighters are a significant menace. The RAF by March '42 already had the ability to put 1000 bombers over the target by night. And in '42 those raids were starting to bite deep, culminating in Hamburg a year later, easily the worst raid prior to 1945. And these raids were at night, with the constant fear of NJGs and the inherent navigational issues affecting accuracy. how much more devastating if the raids were unintercepted, and conducted by day. It alters the equation of the strategic offensive enormously. In fact there is every reason to support the notion that LW would be forced to pull back 80-90% of their available fighters for reich defences in '42, exactly as they were forced to do in '44 when the US began its deep penetration escorted raids.



How do you want to have initiative against the Kammhuber Line and do such raids unintercepted?
The Kammhuber Line with it's search radar is fact since 1940! And to my knowledge radar is functioning at day and night!

The only effect would be a deeper defending system of the JG's against the P51 and the Nightfighters of the LW, from 1941/42, would be the bomber interceptor of the day with the FW 190A and the BF 109F as P51 interceptor. Also all short comings of the Kammhuber Line at night wouldn't exist at day, so the german search radar could work at it's full potential.

Or do you want to tell us the RAF had the possibility at 1941/42 to do 500 or 1000 bomber raids at day *and* night?

A Merlin 45 powered P51 would not have the performance of a Spitfire MkV because it would be 2000kg heavier (full loaded) then a Spit MK V.
So I don't see how the P51 (with Merlin 45) will be an efffective escort fighter. 
Both the FW 190A and the Bf 109F were at 390 to 397 mph combat high speed at 1941/42, so I don't see any significant advantage of the P51 at that timeline, but it would be much slower in climb performance against both german counterparts. And also as reallife has shown against the Spitfire MK V turning performance isn't that important compare to speed, climb and role rate.

Sorry but this argumentation had nothing to do with the military, performance and most important the technology facts from 1941/42.
It wouldn't be that easy with an "underperforming" P51 (Merlin45), compare to the Bf 109F and FW 190A, to destroy the LW. 
To me, it is more the opposite, because the LW could play all it's good parts much more easily at day light and as I said I have great doubts that a P51 Merlin 45 powered was in the same performance leage as a Spitfire Mk V except perhaps speed.


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## pinsog (Apr 4, 2012)

Originally Posted by pinsog 
"I repeat P51 was excellent, top escort fighter (along late p38s) but during all its carrer i could see better dogfight/air superiority airframes,
Many german pilots had this opinion too"

I didn't post that. I replied to it in an earlier thread. I disagree with the above statement. I believe the Mustang was a better airframe.


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## davparlr (Apr 4, 2012)

jim said:


> a) MW50 was nothing special, 150 octane fuel was special


That is why I used 67" in comparing the B to the Bf-109F. 67" did not need 150 octane. With this capability the P-51B was 50 mph faster than the Bf-109F with similar climb. 150 octane allowed 75" and provided overpowering performance.


> b) Ki84 why was not fast? 2000hp in a relatively small airframe


It was fast but not as fast as the P-51D


> C) P51A accelarated very slowly to its top speed. It is reported in this forum


Yes but its top speed was 20 mph faster than the Bf-109 could go. A better comparison would be who was faster to 325 mph from 300 mph. I suspect the P-51 would win this since the Bf-109 was running out of available hp where the P-51 was not.


> d)F4 is 41/42 machine


P-51 was indeed only becoming available and had not flown a mission.


> e) G56 was 685-700 km/h machine


Impressive machine, a bit slower than the P-51B but looks to be formidable. I never found the 700 km/h number.


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## DonL (Apr 4, 2012)

> That is why I used 67" in comparing the B to the Bf-109F. 67" did not need 150 octane. With this capability the P-51B was 50 mph faster than the Bf-109F with similar climb. 150 octane allowed 75" and provided overpowering performance.



Which source do you have for this claim? From testflights the Bf 109F4 was 660 km/h (emergency output 5 min.)fast and now you want to tell me that the P51*B* was 740 km/h fast?
Kurfürst - Mtt. AG. Datenblatt, Me 109 G - 1. Ausführung

What source do you have for the equal climb performance?



> Yes but its top speed was 20 mph faster than the Bf-109 could go. A better comparison would be who was faster to 325 mph from 300 mph. I suspect the P-51 would win this since the Bf-109 was running out of available hp where the P-51 was not.



Any comparation or source for this claims especially for the P51 *A*

I haven't seen so much tendential claims at this forum at a long time!

Edit:
The P51 A had a speed advantage of 20 mph at SL till 10000ft (5 mph)!
From 10000ft to 15000ft the speed is equal and after 15000ft the Bf 109F is much faster.

At 20000ft 410 mph (Bf 109F4) ,373 mph (P51 A)
At 25000ft 400 mph /Bf 109F4), 357 mph (P51 A)


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## gjs238 (Apr 4, 2012)

davebender said:


> The P-51B and P-51D had extreme range to meet a requirement unique to the U.S. Army Air Force. Other nations aren't going to build such a flying fuel tank if it isn't needed. Just as the U.S.A.A.F. wasn't going to arm and armor the P-51 for shooting down hordes of enemy bombers without a need to do so.


 Fuel = endurance. This is useful for more than just range.


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## Vincenzo (Apr 4, 2012)

imho the P-51 it's not the right reply to problem. sure is a clean and new (the production started 7 months late of that of Friedrich) design with high speed but it's also a heavy plane. whatever engine you put in it in 1941 you get a fast fighter (relatively to engine power) but with bad climb (and accelaration) performance. So for 1941 i got to choice a lighter plane as best airframe for a common cheap fighters (my candidates, Friedrich, C.202) , if you need a long range idk if Mustang is best of a Zero for that mission.


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## Shortround6 (Apr 4, 2012)

Vincenzo said:


> imho the P-51 it's not the right reply to problem.......



Which problem?

The original Mustang had the space to hold four 20mm guns with a decent amount of ammo. 

It had the ability to carry a pair of 500lb bombs (not one) before you get to the Merlin versions.

It did have ability to hold more powerful engines without a major degradation in flying qualities.

It may not have been the best in any one category ( or two) but what other airframe could do as well in as MANY catagories?


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## DonL (Apr 4, 2012)

The problem is the definition!

I'm inclined to agree that the P51 was the best airframe at 1941 with a close matchup of the FW 190 (all what you have above mentioned, you could also write about the FW 190). 

But we have here more then one discussion about the P51 and I realy doubt, that a P51 at 1941 with the engines of this timeline (Merlin 45) could be a successful escort fighter against the Bf 109F and FW 190A. The airframe of the P51 was getting better with each more powerful engine step, but the engines at 1941/42 were not powerful enough for the escort fighter missions.


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## Vincenzo (Apr 4, 2012)

short the problem is the definition, the title of thread, the tomo ask.
you can put 4 20mm, the bombs also in a Hurricane... the 51 is a large plane it's obvious that can load many weapons.
the trouble is that fighter first mission is shoot down enemy fighters and 51 is not so good in this in 41, whatever 41 engine you put in it.
the 190 also is a heavy plane and with '41 engine has trouble


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## Shortround6 (Apr 4, 2012)

Give the Mustang the same engine as the Hurricane II and see what happens. The Merlin 45 was the 2nd best Merlin at the time. The Spitfire never got the '_best_' 1941 Merlin because they were still trying to keep the Hurricane in the game. 

A P-51A with 9.60 supercharger gears could get 1150hp at 17,500ft with RAM. it could do 408mph at 17,500ft, at 25,000ft is was supposed to do 395mph using 836hp. 
I wonder what it could do using a Merlin XX giving 1120hp at 18,500ft without ram? 1120hp at 20,500ft? 1000hp at 25,000ft?

Climb at 20,000ft was supposed to be 1980fpm using 910hp. 

I wonder what it would have been using 1050-1075hp at the same height (less RAM while climbing) from the Merlin XX?

The Merlin XX gives nothing away at low altitude like the Merlin 45 would. 

Tomo asked what was the best all around fighter airframe, not what was the best point defense interceptor or best for fighter to fighter combat. If you need another airframe to perform the bomber intercept mission then the claim to best "_all around_"is already fading fast.


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## tomo pauk (Apr 4, 2012)

To make numbers even more suitable for comparison:
- V-1710-81 (for P-51A) makes 1125 HP at 14600 ft, no ram; ram effect elevates the FTH for almost 3000 ft (to 17500); SR6 covered the high speeds power available for climb.
- V-1650-1 (for P-40F*) makes 1120 at 18500 ft, no ram. Lets elevate the (second gear) FTH some 3000 ft, due to ram effect - the thinner air at 21500 enables the plane to make 415 mph there, 405 at 25000 ft. Hope it makes sense.

The weight of the plane might be an issue for a defender that need to climb at 20-30000 ft, but not for the plane making escort job (taking off from UK and flying to the Continent). He is already at good altitude when above Belgium. And P-51 is no snail under 20000 ft either. 

* basically a late 1940 vintage engine


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## riacrato (Apr 4, 2012)

DonL said:


> Which source do you have for this claim? From testflights the Bf 109F4 was 660 km/h (emergency output 5 min.)fast and now you want to tell me that the P51*B* was 740 km/h fast?
> Kurfürst - Mtt. AG. Datenblatt, Me 109 G - 1. Ausführung


 
DonL, I think you might've made a mistake here. As explained by Kurfürst (Kurfürst - Mtt. AG. Datenblatt, Me 109 G - 1. Ausführung) the data sheet you mention is likely not corrected for compressiblity errors, hence there is an error margin.

It is likely the F-4 with climb-and-combat power is really 635 km/h (395 mph) fast.

However with start-and-emergency power (cleared probably sometime in early-mid 1942) it has 150 PS more available and could very well reach 660 km/h (410 mph) and I have seen primary sources going as high as 670 km/h (416 mph).


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## DonL (Apr 4, 2012)

riacrato you are quiet correct, sorry was my failure.

I have also seen the primary sources with start-and-emergency power at 670 km/h (415mph).

But that changed nothing if we take combat power 395 mph or start and emergency power 410-415mph, no P51 B was ever 50 mph faster and a P51 A was slower and not 20 mph faster then a Bf 109F-4!


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## parsifal (Apr 4, 2012)

> How do you want to have initiative against the Kammhuber Line and do such raids unintercepted?
> The Kammhuber Line with it's search radar is fact since 1940! And to my knowledge radar is functioning at day and night



I know, as it was in 1944, when the Americans began their heavy daylight raids over Germany. To counter those raids, just over the Reich itself, the LW needed about 1600 fighters, and still failed in a fairly short space of time. The 8AF was still fielding less bombers per raid and flying a leser number of sorties than the RAF even 1.5 years later after these first big raids initiated by BC. 




> The only effect would be a deeper defending system of the JG's against the P51 and the Nightfighters of the LW, from 1941/42, would be the bomber interceptor of the day with the FW 190A and the BF 109F as P51 interceptor.



Which s exactly what the germans did in 1944 and failed. The Night fighters were often called upon to fly both day and night to try and stem the emergency. Placed a terrible strain on the Night Fighter crews and was hugely wasteful of them as a resource, and still made no difference to the outcome. 

The main reason IMO why the RAF did not concentrate on a daylight bomber force was because it lacked any real long range fighter escort. Give the British a long range escort and there is no reason why they cannot switch to a daylight precision bombing offensive. Given that the RAF represented well over 90% of the bombing effort in 1942, why would it be possible for the LW to mount a better defence with the same detection system and a far lesser number of fighters. That is is not logical. 



> Also all short comings of the Kammhuber Line at night wouldn't exist at day, so the german search radar could work at it's full potential.



To be honest I was unaware the Kammhuber line had too many shortcomings at night. Im assuming that as a system it would operate as well as it did in 1944. Which gave the LW warning day or night (not considering Window) but still necessitated the committment of more than 1500 day fighters to try and counter the efforts of some hundreds of Mustangs escprting a force with an average strike siz of about 500 or so bombers. If the british adopte a similar approach, why is it impossible or unlikely that the germans would need to react in a similar fashion...ie deploy a massive force against the British in 1942 operating the same as the Americans did in 1944 



> Or do you want to tell us the RAF had the possibility at 1941/42 to do 500 or 1000 bomber raids at day *and* night?



Not in 1941 over germany. Thats was shown to be a failure, and by the end of 1941 BC was close to defeat. Not because of the efforts of the LW....losses were heavy but tolerable, but because they couldnt hit the side of a barn door at night. if they had had the ability to operate by day with a proper LR escort, they would not have been thwarted in that way. 

But 1942 does raise an intersting question about the level of operations that could be sustained by the RAF. The typical sorties rate per month by the RAF in 1942 was about 2-3000 sorties per month according to Varley. The peak month was June with just over 5000 sorties per month. According to that same source("Aspects of the Comined US and Allied strategic Air Offensive") the British were dropping about 2-3000 tons of bombs each month (the range from March through to december was 2500-7000 tons per month) 

By comparison, the 8AF did not reach those figures until after October 1943, but thereafter the US effort ramped up very quickly . In terms of sortie rates and bomb tonnages dropped, the US effort in february 1944 was about twice that in tonnage dropped, and about three times that in terms of sorties flown of the averages achieved by the RAF in 1942 (after March). by extrapolation that means to provide the same level of defence if the RAF was operating on an escorted basis in daylight, the LW would need around 5-600 SE fighters over Germany to achieve the same level of defence. since the german effort in 1944 was defeated it therefore follws that they need to mount a much bigger effort in 1942 in order to avoid defeat at that earlier time. Conservativeloy I think they would need to commit a minimum of 1000 a/c just over the Reich itself against the RAF operating with an effective lr daytime escort and with the capability tooperate by day or night 

A


> Merlin 45 powered P51 would not have the performance of a Spitfire MkV because it would be 2000kg heavier (full loaded) then a Spit MK V.



Not according to some of the posters. They seem to think it would be a fast or nearly as fast and effective as just about all the fighters in 1942. 



> So I don't see how the P51 (with Merlin 45) will be an efffective escort fighter.
> Both the FW 190A and the Bf 109F were at 390 to 397 mph combat high speed at 1941/42, so I don't see any significant advantage of the P51 at that timeline, but it would be much slower in climb performance against both german counterparts. And also as reallife has shown against the Spitfire MK V turning performance isn't that important compare to speed, climb and role rate.
> 
> Sorry but this argumentation had nothing to do with the military, performance and most important the technology facts from 1941/42.
> ...



I cant really respond to that (except to say that I think you are playing up the strengths of the LW and not looking at the overall issue) , but note that others dont agree with you. You will have to take it up with them, I guess.


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## Cola (Apr 4, 2012)

DerAdlerIstGelandet said:


> Why? Because he is asking about the airframes in use in 1941...


Why putting Fw190 and P51 in, then?


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## Siegfried (Apr 4, 2012)

DonL said:


> riacrato you are quiet correct, sorry was my failure.
> 
> I have also seen the primary sources with start-and-emergency power at 670 km/h (415mph).
> 
> But that changed nothing if we take combat power 395 mph or start and emergency power 410-415mph, no P51 B was ever 50 mph faster and a P51 A was slower and not 20 mph faster then a Bf 109F-4!



I would be highly dubious over claims that involve the Luftwaffe replacing the Me 109F4 with a G1 that is 20 mph slower and less maouverable.


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## Milosh (Apr 4, 2012)

Siegfried said:


> I would be highly dubious over claims that involve the Luftwaffe replacing the Me 109F4 with a G1 that is 20 mph slower and less maouverable.



Some units of JG2 replaced their 109Fs with Fw190As and some G-1s. The G-2, essentially a G-1 without pressurization, replaced the 109Fs in several JGs.


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## DerAdlerIstGelandet (Apr 4, 2012)

Cola said:


> Why putting Fw190 and P51 in, then?



Because the Airframes were available.

P-51
First Flight: 26 October 1940 (That makes the Airframe available)
Became Operational: The RAF became the first to use the P-51 (Mustang Mk. I) in 1941. 

Fw 190
First Flight: 1 June 1939 (Makes the Airframe Available)
Became Operational July/August 1941 (further confirms the airframe was available)

Even if they were not in service in 1941 (these two aircraft were however), the airframes themselves were still available. That is what the thread starter is asking for. He is not asking for service in numbers or anything like, just available airframes.


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## tomo pauk (Apr 4, 2012)

Siegfried said:


> I would be highly dubious over claims that involve the Luftwaffe replacing the Me 109F4 with a G1 that is 20 mph slower and less maouverable.


 


Milosh said:


> Some units of JG2 replaced their 109Fs with Fw190As and some G-1s. The G-2, essentially a G-1 without pressurization, replaced the 109Fs in several JGs.



If I'm having this right: the Bf-109G-2 was able to make some 660-665 km/h, using the Notleistung (1475 HP). The plane is maybe a tad heavier, but has 125 HP more than Bf-109F-4 on Notleistung (1350 HP); total drag is just a tad bigger for the G-2? So it's maybe 650 km/h for such an F-4?


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## DonL (Apr 4, 2012)

> I would be highly dubious over claims that involve the Luftwaffe replacing the Me 109F4 with a G1 that is 20 mph slower and less maouverable.



Very good sentence, but if you read primary sources, then you will see that it is the truth!

The Bf 109G was clearly a jump back from aerodynamics to the Bf 109F and as riacrato mentioned, for the DB 601E start and emergency power (1350PS) was cleared probably sometime in early-mid 1942, but for the DB 605A was only combat power available till the end of 1943.
According to many very good german LW historians, the decision of the introduction of the Bf 109G at 1942 and the simultaneous change of the engine production from DB 601E to DB 605A, was a heavy failure, because the aircraft wasn't a step forward and the engine,especially at the Bf 109G with it's too smal oil supply and other special problems between Bf 109G and DB 605A, was 1942 too troublesome for introduction. 

A Bf 109F-4 with cleared start and emergency power could outperform a Bf 109 G1/G6 with "only" combat power at any time, till the best altitude of the produced DB 601E engines. This was stated from many JG pilots! Many pilots prefered the F-4 over the G as long as enough spare parts reach their units.

@ parsifal

I don't think that you can compare the situation of 1943 and 1944 to the situation of 1941/42 especially when the RAF was at it's own feet without the help of the USA and the 8th AF and at the same time, the LW had more strenghts compare to the RAF alone and was much better from quality (Pilots and aircrafts). The Bf 109 F-4 and FW 190A3 were the cutting edge at 1942 at the ETO.
The situation was fundemental different at 1943/1944 from the quality/performance of the aircrafts and the pilots.



> To be honest I was unaware the Kammhuber line had too many shortcomings at night. Im assuming that as a system it would operate as well as it did in 1944. Which gave the LW warning day or night (not considering Window) but still necessitated the committment of more than 1500 day fighters to try and counter the efforts of some hundreds of Mustangs escprting a force with an average strike siz of about 500 or so bombers. If the british adopte a similar approach, why is it impossible or unlikely that the germans would need to react in a similar fashion...ie deploy a massive force against the British in 1942 operating the same as the Americans did in 1944



One Himmelbett could only direct 2 Nightfighter at the same time to enemy bombers, this problem was solved with the introduction of the Lichtenstein Radar (mid 1942). At day light every Bomber interceptor could search his own target at the same time, what will make a huge difference.



> Not according to some of the posters. They seem to think it would be a fast or nearly as fast and effective as just about all the fighters in 1942.





> I cant really respond to that (except to say that I think you are playing up the strengths of the LW and not looking at the overall issue) , but note that others dont agree with you. You will have to take it up with them, I guess.



Till now, nobody had denied that a P51 at 1941/42 would be 2000kg heavier then a Bf 109 F-4 and except the ridiculous claims of davparlr
to the P51 B and P51 A, nobody had shown any serious data's that a long range P51 at 1941/42 could realy match against the Bf 109F-4 and the Fw 190A. There will/is the possibility that it can match perhaps at speed, but not at climb and roll rate. 
A P51 long range fighter at 1941/42 against the Bf 109F-4 and FW 190A2-3, is miles away from the advantage of the P 51B against the Bf 109 G6 or FW 190 A5/6/8. So it would have no advantage the advantage would be at the german aircarfts at 1941/1942!


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## Cola (Apr 4, 2012)

@DerAdlerIstGelandet,
well then if that's so, I suppose He178/280 and particularly Me262 were much more advanced airframes of the time, then either of already metioned.


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## FLYBOYJ (Apr 4, 2012)

Cola said:


> @DerAdlerIstGelandet,
> well then if that's so, I suppose He178/280 and particularly Me262 were much more advanced airframes of the time, then either of already metioned.


Were they combat ready? Did they have relaible and combat ready propulsion systems?


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## drgondog (Apr 4, 2012)

DonL said:


> Till now, nobody had denied that a P51 at 1941/42 would be 2000kg heavier then a Bf 109 F-4 and except the ridiculous claims of davparlr
> 
> *I would deny that the P-51A was 2000kg/4400 pounds heavier. My figures could be wrong but Nowarra suggests that the F-4 at Basic was 2255Kg/4972pounds and max Gross was 2980KG/6570 lbs.. The Mustang IA with 180 gallons of fuel and full armament was 6185/8153 pounds empty/max gross = ~2764KG/3697 Kg so ~ 700Kg more with 4x20mm and 125rpg each (IIRC)??*
> 
> ...



The Mustang 1A/A36 was a formidable fighter below 10,000 feet and acceptable in air combat up to 20000 feet even if slightly outclassed by the 109F and FW 190A3-4. The P-38 and P-40 and Hurricane were below the Mustang IA in most operational altitudes. It wasn't 'helpless' any more than a 109G and FW 190A7 were 'helpless' against the P-51B


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## Vincenzo (Apr 4, 2012)

the trouble is the weight in '41 was not available a 12 cylinders engine that can give enough power for a 8000 lbs fighters, the 51 is fast because is low drag, use fewer fuel for the low drag but the low drag can not compesate the low power/weight ratio, the Friedrich weighing 6400 lbs has not this trouble. also the Spit V, weighing a bit more, has not that trouble (same for the C.202 has around the same weight)

Adler just for precision afaik Mustang was used to RAF from '42 (1st sortie July) (the Fridrich-4 1st sortie maybe june '41)


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## parsifal (Apr 4, 2012)

drgondog said:


> The Mustang 1A/A36 was a formidable fighter below 10,000 feet and acceptable in air combat up to 20000 feet even if slightly outclassed by the 109F and FW 190A3-4. The P-38 and P-40 and Hurricane were below the Mustang IA in most operational altitudes. It wasn't 'helpless' any more than a 109G and FW 190A7 were 'helpless' against the P-51B



Got question to do with the hypothertical though DG. What would be your estimates of Mustang I airframe equipped with one of the earlier merlins? Performance, competiveness, perhaps even likely ranges in RAF service. Im looking for ballpark figures. 

Regards


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## parsifal (Apr 4, 2012)

> I don't think that you can compare the situation of 1943 and 1944 to the situation of 1941/42 especially when the RAF was at it's own feet without the help of the USA and the 8th AF and at the same time, the LW had more strenghts compare to the RAF alone and was much better from quality (Pilots and aircrafts).




We will have to disagree on that. i dispute a huge qualitative difference between the LW and RAF in terms of both equipment and personnel. Certainly there was an edge enjoyed by the LW, but the margins are far smaller than the los sheets suggest. ther were reasons for the one sided loss rates, and they had nothing to do with either pilots or aircraft performance. they had a lot to do with range and LW engegement policies ( only engage when favaourable) 



> The Bf 109 F-4 and FW 190A3 were the cutting edge at 1942 at the ETO.
> The situation was fundemental different at 1943/1944 from the quality/performance of the aircrafts and the pilots.



I think you are over- relying on the qualtitative edge. this might have affected losses by 5-10% but would do nothing to reduce bombing effectiveness. And doesnt avoid the basic need for numbers to counter the threat. They ( the germans still need numbers to be effective) 




> One Himmelbett could only direct 2 Nightfighter at the same time to enemy bombers, this problem was solved with the introduction of the Lichtenstein Radar (mid 1942). At day light every Bomber interceptor could search his own target at the same time, what will make a huge difference.



Err no it wont. This was the same situation as was confronted by the 8AF in 1944, and ultimately failed. Why would it be any more effective in 1942 with perhaps 30% as many fighters to use?


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## Cola (Apr 4, 2012)

FLYBOYJ said:


> Were they combat ready? Did they have relaible and combat ready propulsion systems?


No, but the thread starter specifically asked for airframe.


tomo pauk said:


> In other words, this time on we should discuss the capabilities of the airframe, independently from the engine it was mounted on it.


So, I'm not sure what's going on here...is this P51 vs Bf109 vs Spitfire vs Fw190 thread, or what?


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## pbfoot (Apr 4, 2012)

I believe qualitatively Fighter Commands pilots skill set was not as high as the LW , the reason is simple expansion had diluted whatever skill level Fighter Command possessed all the new crews were being fed into operational squadrons from the ever increasing amount of aircrew being graduated from the BCATP . Many of the aircrew from earlier times had finished their operational tours and were now working in the OTU's or even training command . You also had the Desert AF , Malta even the USSR also the guys flying in CBI not to mention the Pacific with the Kiwis and Aussies . In 44 the situation had come full circle and the aircrews were now very expierienced


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## DonL (Apr 4, 2012)

> We will have to disagree on that. i dispute a huge qualitative difference between the LW and RAF in terms of both equipment and personnel. Certainly there was an edge enjoyed by the LW, but the margins are far smaller than the los sheets suggest. ther were reasons for the one sided loss rates, and they had nothing to do with either pilots or aircraft performance. they had a lot to do with range and LW engegement policies ( only engage when favaourable)



Sorry here we have a misunderstanding! I didn't want to compare the RAF with the LW with the quality statement, I want to say that the quality (pilots and aircrafts) of the LW was much better 1941/42 compare to 1943/44.

Next I think your mixing things between early 1941 and late 1942 and you are a lot to optimistic of the year 1941.

I think that the RAF would have very very heavy losses, if there would be a day light bombing at *1941* with the estimated P51 long range fighter. The RAF had not the strenght neither the supply to apply 2000 a/c (1000 bomber/1000 fighter) to a mission, I realy doubt that at 1941 it could be 1000 a/c (500 bomber 500 fighter) at one mission. At *1941* the LW has absolutely the same advantages as the RAF at BoB at day light bombing raids, plus the Me 110, and all other "Nightfighter" could operate as bomber interceptor (Ju 88, Do 17, Do 215 etc.). There were more then enough numbers to stop such day light bomber raids and the butcher bill would be very huge for the RAF.

If you initiate such day light bombing raids at *1941* I think the RAF would be only a shadow of the real RAF at 1942, because from where you will take the capacity to replace Bombers, Fighters and Pilots?

If you initiate this szenario mid *1942* there will be much better chances or I'm inclined to your opinion, but if you initiate this at early or mid 1941 it would be a very huge desaster for the RAF!


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## CobberKane (Apr 4, 2012)

Yipee, first ever post!

I'm going to go with Mitchell's masterpiece, the Spitfire. Correct me if I'm wrong, but I believe it was the only allied fighter to be produced throught the entire conflict. The Spit started WWII at the cutting edge of piston engined fighter performance and was still at the head of the pack when the curtain fell - an incredible feat for an airframe designed in the mid 1930's. Sure, it fell short in provision for fuel and ease of manufacture and was continually developed throughout the war, but athe the end of the day the Spitfire's airframe was an intergal part of a fighter that was as good as anything in the air from 1939 to 1945 - what other aircraft can that be said of?


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## wuzak (Apr 4, 2012)

Cola said:


> @DerAdlerIstGelandet,
> well then if that's so, I suppose He178/280 and particularly Me262 were much more advanced airframes of the time, then either of already metioned.



Were the He178 and He280 advanced airframes, or just basic airfraes to try out the jet propulsion system?

Certainly the He178 was only ever intended as a research aircraft, and was no more suitable for combat than the Gloster E.28/39


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## drgondog (Apr 4, 2012)

Parsifal - I need to think about it. The key question is what thrust figures and at which altitudes. The drag estimates are pretty much the same across the board.


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## parsifal (Apr 4, 2012)

> Sorry here we have a misunderstanding! I didn't want to compare the RAF with the LW with the quality statement, I want to say that the quality (pilots and aircrafts) of the LW was much better 1941/42 compare to 1943/44.



I understand, but doesnt change the equation at all. Having experienced air crews statistically does not change the enemies loss rates by any measurable amount, except if the qualitative difference is very great indeed. What having experienced aircrew does do is increase their ability to survive.

The majority of BC losses had nothing to do with the efforts of German fighter forces, and I expect the majority of losses for US daylight operations would be similar. For 2 group, operating in an intensely hostile environment, their losses to the two JGs operating near the coast were very limited. far more losses were due to Flak (about 37%), and navigational error or flying accidents (about 35%) with only about 22% ever being lost to the fighters. Similar conclusions can be drawn regarding the fighter forces committed to operations over France in 1941. And the concentrations of German fighters encountered in the coastal regions were far far greater than might be expected over the reich itself in our hypothetical, given the amount of force you are advocating to be diverted (just one JG). historically, in december 1941 there were just two regular day fighter formations deployed in the reich, I/JG-1 and I/JG-3 plus some provisional territorial units flying mostly obsolete types like the Bf 109D which Weisse described in his report at the time as "of questionable value" ( source : "The Luftwaffe over Germany - Defence Of the Reich" john Caldwell ). I have read in total there were about 140 day fighters defending the reich at this time 




> Next I think your mixing things between early 1941 and late 1942 and you are a lot to optimistic of the year 1941.



I am not being overoptimistic given the response you are advocating to the threat and with the forces you are prepred to commit to respond to this threat. You are saying that with 140 fighters (most of them obsolete) plus maybe 60 additional fighters fom just one JG that you are prepared to deploy back to the reich as reinforcements that you can stop a force that in late 1941 could boast a frontline bomber strength of about 600 bombers, plus say 30 squadrons of fighters. If those 30 squadrons were LR mustangs they are going to tear your defences to pieces, unquestionably. Things may be different if there is a wholesale redeployment of LW assets fro the front back to Germany, but you arent advocating that. 



> I think that the RAF would have very very heavy losses, if there would be a day light bombing at *1941* with the estimated P51 long range fighter. The RAF had not the strenght neither the supply to apply 2000 a/c (1000 bomber/1000 fighter) to a mission, I realy doubt that at 1941 it could be 1000 a/c (500 bomber 500 fighter) at one mission. At *1941* the LW has absolutely the same advantages as the RAF at BoB at day light bombing raids, plus the Me 110, and all other "Nightfighter" could operate as bomber interceptor (Ju 88, Do 17, Do 215 etc.). There were more then enough numbers to stop such day light bomber raids and the butcher bill would be very huge for the RAF.




The forces you have proposed to commit in response to this threat are nowhere near what you are now advocating. Remember, you are not proposing a redeployment of the experienced frontline formations to deal with this threat. all you have is a maximum of 200 day fighters, perhaps half of which are obsolete, and only 60 of them with frontline super experience. the rest are chaff basically. As for the Night fighters, in December 1941 there were 6 understrength groups with less than 200 aircraft in total, mostly Ju-88Cs with some Me 110s.

Against escorted formations, NJGs used in the day role were massacred, why would that not be the case in this scenario. with only 200 day fighters (half of them inferiior), you are going to be lucky to place any more than 50 at any given point, against a formation of say 400 bombers and say 250 fighters. That is not going to result in any masscre for the allies, the other way around in fact. 

Historically 2 group (a force of just 6 squadrons in 1941, eqipped mostly with Blenheims), mounted sustained daylighht operations in france against an enemy with far greater concentration of fighters, and with nothing but elite crews. It suffered nowhere near the losses you are suggesting to fighters, though losses to flak and sheer attrition did push that up. there is no evidence from the historical experience to support the claim that losses would be heavy, particulalry when the numbers of defenders is so thin.  



> If you initiate such day light bombing raids at *1941* I think the RAF would be only a shadow of the real RAF at 1942, because from where you will take the capacity to replace Bombers, Fighters and Pilots?



Hardly. in 1941 the Night Bombers of BC were suffering a far heavier attrition rate than the day bombers attacking in France (mostly). if the brits had switched to a day bombing campaign with a decent amount of LR escort, as i am advocating, and they were met by the historical defenders, plus the one group you have deemed as adequate, the result would have been a massacre alright, but not of British aircraft. Losses to british formations if the experienced of 2 Gp are anything to go by would drop from about 7% (the loss rate for the night bombers at this time) per raid, to about 2.5% (the los rates of 2 Gp over France) 



> If you initiate this szenario mid *1942* there will be much better chances or I'm inclined to your opinion, but if you initiate this at early or mid 1941 it would be a very huge desaster for the RAF!



Early to mid 1941 I agree, principally because the Reich defences at that time consisted of over 32 frontline squadrons. After June 1941 there is still a short delay but from september on the Brits are typically sending a force of about 300 bombers. If there were a similar number of fighters joining them, and they are resisted by just 200 defenders across the whole of germany (orf indifferent quality), the RAF has virtualkly nothing to fear.


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## parsifal (Apr 5, 2012)

With regard to the possible daylight operations by the RAF and the likley losses that might be incurred from the historically deployed defenders, plus just one JG we dont really need to speculate as to the likley losses, we can look at actual daylight raids of the period. Ive taken this information from the Air Situation Report for the week see TNA CAB 66/18/17



"The heaviest daylight bombing raid against Germany since the outbreak of war was carried out with considerable success on the 12th August. In this major operation 78 bombers and 485 fighters were employed; the targets were two of the main power stations in the Rhineland—the Goldenburg at Cologne-Knapsack and the Quadrath Fortuna at Cologne.

The day’s operations began with a sweep by 84 fighters escorting 6 Hampdens in an attack on St. Omer aerodrome, the object being to draw off the enemy force based in the district ; it is estimated that 150 Me. 109s were engaged in the combats which ensued.

While this operation was in progress 54 Blenheims, escorted by Whirlwinds of Fighter Command, left the coast and, flying low over the sea, penetrated through the mouth of the Scheldt to Antwerp, where the covering Whirlwinds returned to base. Simultaneously, a Fortress bombed De Kooy aerodrome from 32,000 feet, to keep enemy fighters in that area employed.

Meanwhile the Blenheims, flying close to the ground, located and attacked, under favourable weather conditions, the two power stations at Cologne. From reports received, both power stations appear to have been severely damaged in most determined attacks ; 24 tons of bombs were dropped on the turbine and boiler houses and the targets were left with fires blazing.

Heavy A.A. fire was encountered, but only three Me. 109s were seen; further diversions by Fortresses over Cologne and the naval base at Emden assisted in drawing off enemy fighters, which might otherwise have attacked. These Fortresses released their bombs from 35,000 and 37,000 feet respectively.

The Blenheims were met at Antwerp on their homeward journey by formations of Spitfires and, during this withdrawal, a further diversion was carried out by 144 fighters escorting 6 Hampdens to attack Gosnay Power Station, near Bethune; bursts were seen on or around the target. Later, 4 Blenheims with fighter escort bombed the shipyards at Le Trait, near Rouen, hits being obtained on slipways and on a ship alongside.

In this series of co-ordinated operations we lost 12 Blenheims and 10 fighters. Four enemy aircraft were destroyed, 5 probably destroyed and 10 damaged." These last figures are confirmed by Foreman as a further 4 written off immediately and 3 further cannibalised. two were unnaccounted for by Foreman. Thats an exchange rate of 22 a/c to all causes to 11 enemy aircraft, just to the allied fighters. thats not the mark of a one sided victory, or the germans enjoying a runaway qualitative superiority. the reverse actually. just 

Breaking down those losses, thats a loss rate of 3.9% of the force structure, using obsolete bombers, and with a large part of the bomb run carried out unescorted. One additional JG, however wel trained it might be, is not going to make any difference, and losses due to enemy fighters unlikley to increase, more likley to decrease because of the ability to provide continuous escort


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## DerAdlerIstGelandet (Apr 5, 2012)

Cola said:


> No, but the thread starter specifically asked for airframe.
> 
> So, I'm not sure what's going on here...is this P51 vs Bf109 vs Spitfire vs Fw190 thread, or what?



No, this is a thread to discuss the airframes available in 1941, which everyone here seems to be doing. 

Either contribute to the discussion, or move to another thread that suits you better. Everyone here seems to be on topic.


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## Cola (Apr 5, 2012)

wuzak said:


> Were the He178 and He280 advanced airframes, or just basic airfraes to try out the jet propulsion system?
> Certainly the He178 was only ever intended as a research aircraft, and was no more suitable for combat than the Gloster E.28/39


 
Good points, but still He178 flew 2 years ahead of E.28 and paved the way for the next 30 years of Soviet intake design.
He280 solved nose, tricycle gear layout and nacelles, later accepted by Me262.
Finally, 262 featured swept wing of low t/c ratio (a hint of supercritical profiles) and large amount of body lift, something planes like F22 extensively utilize, today.
Also, 262's aerodynamic testing and final layout was done in '41 (V1 had piston engine just for the purpose of actual flight testing), so it wins airframe contest of the age (for the most advanced design), light years ahead of competition.

As far as the piston fighters go, the situation is, well, difficult to assess and this is why I said no such thing as best airframe...
However, think you boys need to get your hands on proper figures before making conclusions, so...
Kurfurst - Your resource on Messerschmitt Bf 109 performance is a site you wanna look for Bf109 actual data.
For the rest you go there > WWII Aircraft Performance
(DISCLAIMER: Not sure if you're already using this, but I see data often being disputed, so this may help solve the problem)


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## parsifal (Apr 5, 2012)

drgondog said:


> Parsifal - I need to think about it. The key question is what thrust figures and at which altitudes. The drag estimates are pretty much the same across the board.



The question arose because of the claim that in 1941 the only or best engine available would be the Merlin 45. I initially accepted that as a fact, but just a little research shows that claim to be not entirely true.

According to John Foreman (Fighter Command War Diaries January 1942-June 1943) the merlin 60 series was first bench tested in April 1941, with the intention of fitting it to a high flying version of the Wellington. It was not until July 1941 that the question was first raised as to the possibility of fitting the new engine to the Spitfire airframe. the first Spitfire fitted with a Merlin 60 (which was later redesignated Merlin 61) was fitted to a Spit III that had been modified, with very impressive results....top speeds of over 400 mph. There was then official resistance to its introduction to SE fighters, but eventually a certificate of design was issued April 1942, and the new Merlin 61 entered widespread service in FC from July 1942, principally in the Spit IX, which is generally seen as an effective counter to the FW190. 

The decision to marry the Merlin 61 to the Mustange airframe was not taken until July 1942, I understand, and it service deliveries of the first P-51Bs was not until the end of 1942. However, I cannot see why, with a little more foresight and drive, why the Mustang airframe and the brand new engine could not have been developed from the start, entering service from the beginning of 1942. The basic airframe was ready from the beginning of 1941, the engine was ready by Septemeber 1941. If there had been some inspired decisions made more quickly, i cannot see why it would not have been possible for a RAF Mustang/Merlin 60 marriage to have occurred from the beginning of 1942 instead of the end.

Certainly the claim that the only engine available to the Mustang in 1941 is bogus. Potentially a marriage between the two stage Merlin and the basic Mustang I airframe was possible from the middle of 1941. If so, what a lost opportunity....


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## Shortround6 (Apr 5, 2012)

While the Merlin 61 may not have been ready the Merlin 45 was not the best Merlin available, a Merlin 20 series was. The Merlin 45 with a two speed supercharger that offered about another 1000ft of altitude over the Merlin 45 and with the low gear, much better performance than the 45 at the lower altitudes.

It offered 20-30mph in the P-40 over the -39 Allison at 20-25,000ft. The higher the altitude the greater the difference. With the same sort of change to the Mustang the Mustang could have been a very creditable fighter in 1941 even if not the performer it would become in 1943.


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## Vincenzo (Apr 5, 2012)

the merlin 61 production was not started in '42? in '41 we have only prototypes


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## drgondog (Apr 5, 2012)

Cola said:


> Good points, but still He178 flew 2 years ahead of E.28 and paved the way for the next 30 years of Soviet intake design.
> He280 solved nose, tricycle gear layout and nacelles, later accepted by Me262.
> Finally, 262 featured swept wing of low t/c ratio (a hint of supercritical profiles) and large amount of body lift, something planes like F22 extensively utilize, today.
> Also, 262's aerodynamic testing and final layout was done in '41 (V1 had piston engine just for the purpose of actual flight testing), so it wins airframe contest of the age (for the most advanced design), light years ahead of competition.
> ...



You might want to assume that those sources are well known and extensively used by this group.

Why don't you propose your selection criteria and conclusions?


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## parsifal (Apr 5, 2012)

Vincenzo said:


> the merlin 61 production was not started in '42? in '41 we have only prototypes



I agree, but its delay does not appear to be due to any technical difficulty. it was due Air ministry resistance. To me it looks like it could have been in production from the end of 1941

also whilst the Merlin 61 was not in production until the latter part of 1942, I am not sure about its immediate forebear, the Merlin 60, which from what little Ive read appears to virtually the same engine and had begun to be installed into aircraft like the Lancaster from early 42. I will stand corrected if wrong, because I am not 1005 sure. What is certain, however is that engine intended for SE Fighter installtion, the merlin 61 was delayed by bureacracy, not technology


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## Cola (Apr 5, 2012)

drgondog said:


> You might want to assume that those sources are well known and extensively used by this group.


Ok, then...it's just that I saw some inaccurate figures here f.e.:


davparlr said:


> Some stats
> Bf-109F *1150 hp* *324 mph* at SL
> Fw-190A-3 *1730 hp* *335* mph at SL
> Spit II *1090 hp* *290 mph* at SL
> P-51 (Allison) *1150 hp* *344 mph* at SL


So, I figured original documents my prove to be useful.



> Why don't you propose your selection criteria and conclusions?


Well, you can't really do that.
To this day, I'm not aware of a design that beats the competition in every aspect.
So, IMO the discussion would be more fruitful, should it address separate items (wing, fuselage, engine, etc...), separately.


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## Vincenzo (Apr 5, 2012)

parsifal said:


> I am not sure about its immediate forebear, the Merlin 60, which from what little Ive read appears to virtually the same engine and had begun to be installed into aircraft like the Lancaster from early 42. I will stand corrected if wrong, because I am not 1005 sure. What is certain, however is that engine intended for SE Fighter installtion, the merlin 61 was delayed by bureacracy, not technology



i never read of 2 stage merlin on Lancaster except the merlin 85 series, you talking of test planes?


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## davparlr (Apr 5, 2012)

DonL said:


> But that changed nothing if we take combat power 395 mph or start and emergency power 410-415mph, no P51 B was ever 50 mph faster and a P51 A was slower and not 20 mph faster then a Bf 109F-4!



At SL, the Bf-109F-4 was capable of 327 mph (per Kurfurst)
At SL, the P-51B pulling 67" was capable of 372 mph without racks (I guess I was wrong, it is only 45 mph faster)
At SL the P-51B pulling 75" (150 octane), post May '44, was capable of 388 mph without racks, or 61 mph faster.


From AAF test as shown in Spitfireperformance

Max Speed at SL, P-51B

67" with wing racks 364 mph

75" with wing racks 380 mph

75" without wing racks 388 mph


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## parsifal (Apr 5, 2012)

Vincenzo said:


> i never read of 2 stage merlin on Lancaster except the merlin 85 series, you talking of test planes?



Thanks Vincenzo, as i said I will stand corected, but doesnt alte that one of the reassons for the delayed introduction of the merlin 61 was official stubborness by the air ministry


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## drgondog (Apr 5, 2012)

Cola said:


> Well, you can't really do that.
> To this day, I'm not aware of a design that beats the competition in every aspect.
> So, IMO the discussion would be more fruitful, should it address separate items (wing, fuselage, engine, etc...), separately.



If the discussion is Airframe, not armament, not engine, not fuselage - but the totality of the airframe and its capacity to evolve - then pick your own criteria. It would be just like picking Jim Brown over Johnny Unitas or Jordan over Magic - take a stand.


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## davparlr (Apr 5, 2012)

Cola said:


> Ok, then...it's just that I saw some inaccurate figures here f.e.:
> 
> So, I figured original documents my prove to be useful.



Bf-109
Kurfürst - Mtt. AG. Datenblatt, Me 109 G - 1. Ausführung

Fw-190
http://www.wwiiaircraftperformance.org/fw190/fw190-a3-climb-speed-26-11-42.jpg

Spitfire Mk-II

http://www.spitfireperformance.com/p7280speed.gif


P-51A (note: I took the data showing 1150 hp to equalize it with the other aircraft, as much as possible)

http://www.wwiiaircraftperformance.org/mustang/P-51A-1-43-6007-Chart-1400.jpg


Please show me the data you have that indicates that these are wrong.


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## wuzak (Apr 6, 2012)

parsifal said:


> I agree, but its delay does not appear to be due to any technical difficulty. it was due Air ministry resistance. To me it looks like it could have been in production from the end of 1941
> 
> also whilst the Merlin 61 was not in production until the latter part of 1942, I am not sure about its immediate forebear, the Merlin 60, which from what little Ive read appears to virtually the same engine and had begun to be installed into aircraft like the Lancaster from early 42. I will stand corrected if wrong, because I am not 1005 sure. What is certain, however is that engine intended for SE Fighter installtion, the merlin 61 was delayed by bureacracy, not technology



Not sure about the Melin 60, if it existed at all.

The two stage Merlin was originally intended for the high atitude Wellington variant. But someone (Lord Hives?) suggested that would be a waste and it should be put in the Spitfire.

The delay may have been due to tooling for the changeover - remember that the single stage engines in production at the time had the troublesome single block/head arangement, the two piece design being held back in UK production until the two stage engine went into production.


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## parsifal (Apr 6, 2012)

According to foreman, it existed, at least in prototype form, and was tested in the spitfire airframe (a spit III) in late september 1941. According to foreman this installation, but he also says that there was considerable resistance to its introduction, with type certification not given until the following april. thats a delay of 8 months for reasons i do not understand. Tooling for series production did not commence until certification was granted In april, and the first mass produced versions of the merlin 61 appeared from July. The 8 months delay that preceded the issue of the type certification cannot be explained by 'tooling up arguments. it may have occurred as a result of technical issues but unlikley given the results of the test flights carried out in September.


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## Cola (Apr 6, 2012)

davparlr said:


> P-51A (note: I took the data showing 1150 hp to equalize it with the other aircraft, as much as possible)
> http://www.wwiiaircraftperformance.org/mustang/P-51A-1-43-6007-Chart-1400.jpg
> Please show me the data you have that indicates that these are wrong.



Ah, ok...thought you were talking about Mk.I (V-1710-39), but "A" is from mid '42 so you can hardly compare it to SpitII or Bf109F, although F4 was still faster at altitude.
Chronologically, 109G or SpitIX would be a better match.


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## davparlr (Apr 6, 2012)

No.

In comparing airframes, what is important is the hp used verses airspeed attained. I used this chart because it had a distinct power setting test for the P-51 of about 1150 hp which very close to the Bf-109F hp of 1165. The airspeed of the Spit looks quite small so I am suspect that the hp may be wrong. However, even the much more powerful IX top speed at SL is only about 330, quite a bit lower than the max shown by the chart for the P-51A.

For any given hp and altitude, the P-51 airframe will substantially out perform the other three aircraft in airspeed. The P-51 airframe is the most aerodynamically efficient airframe of any major propeller fighter of WW2. The Fw-190D-9 is a close second.


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## tomo pauk (Apr 6, 2012)

I'm not that fluent with this, so bear with me 
A table from Lednicer's analysis shows Cdswet of the P-51s as being in league of it's own, while the Spit IX and Fw-190D-9 are comparable - meaning D-9 is not that close second?


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## Vincenzo (Apr 6, 2012)

davparlr said:


> No.
> 
> In comparing airframes, what is important is the hp used verses airspeed attained. I used this chart because it had a distinct power setting test for the P-51 of about 1150 hp which very close to the Bf-109F hp of 1165. The airspeed of the Spit looks quite small so I am suspect that the hp may be wrong. However, even the much more powerful IX top speed at SL is only about 330, quite a bit lower than the max shown by the chart for the P-51A.
> 
> For any given hp and altitude, the P-51 airframe will substantially out perform the other three aircraft in airspeed. The P-51 airframe is the most aerodynamically efficient airframe of any major propeller fighter of WW2. The Fw-190D-9 is a close second.


 
the 51 out perform in max speed but not in all others performances

taking for good your power
power/weight 51 1150/8000= 0.14 HP for lbs
power/weight 1099F 1165/6400= 0.18 HP for lbs

over 25% advantage for 109F so what planes has best acceleration or best climb?


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## drgondog (Apr 6, 2012)

tomo pauk said:


> I'm not that fluent with this, so bear with me
> A table from Lednicer's analysis shows Cdswet of the P-51s as being in league of it's own, while the Spit IX and Fw-190D-9 are comparable - meaning D-9 is not that close second?



This is tricky in one sense. 

Flat Plate Drag is all about dynamic pressure 'q' and S=wing area as they relate to Total Drag - and used to provide a reasonable comparison between two aircraft. This is all about resolving Total Drag (incl Zero Lift Drag of the wing, parasite drag, friction drag, profile drag and even compressibility drag) against the usual major component - the wing). Hence the wing area reference. 

CDwet is about referencing Total Drag as a function of the entire surface of the aircraft, more of a funtion of the comparison of all the forces 'pulling' on the aircraft. 

Remember both the Mustang and Spit had wing areas of 16 and 20% greater than the 190A and D models so if all of these birds were compared at the same speed and altitude (q1=q2=q3=q4) then it (Flat Plate Drag) says something about the relative amount of power (Thrust=f(hp/V)) required to maintain that speed - all other things being equal (which they are not). 

In the above analysis the FW 190-D at 4.77 Sq ft is only 2% above the P-51D while the Spit at 5.4 sq ft is 16% more flat plate drag, so the FW190D-9 is indeed a close second relative to total drag expressed as a function of wing area and dynamic pressure.

While the Flate Plate drag is referenced to dynamic Pressure it gives you a nice sense of relative 'delta' Hp requirements to increase speed, accelerate, versus another airframe and if the Flat Plate Drag is calculated at top speed the contrast between that value and another airframe gives you a nice relative airframe aerodynamic efficiency.


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## tomo pauk (Apr 6, 2012)

Bill, for the sake of discussion, let's 'increase' the Fw-190D's wing to the size of Spit or P-51. Beside the wetted area that would increase, what happens to the 'f' and Cdwet?


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## Shortround6 (Apr 6, 2012)

Vincenzo said:


> the 51 out perform in max speed but not in all others performances
> 
> taking for good your power
> power/weight 51 1150/8000= 0.14 HP for lbs
> ...



The 109 will have an advantage in climb, it will have an advantage in acceleration from low speed.

The advantage in climb can be large but perhaps not as much as you think. What matters is the surplus power available after you take out the power needed to maintain a given airspeed. Best climb speeds are usually down under 200mph if not closer to 150mph. It may only need 250-350hp to fly the plane at those speeds with the rest of the power being available for climb. the lower drag plane needs a bit less power for the same speed and so has a a slightly higher percentage of power avaialbe for climb. nowhere enough to out climb the 109 but as speeds go up things even out. 

If you are at an altitude where the 109 can do 325mph and the P-51 can do 340mph, the 109 cannot climb at all without loosing speed. The P-51 if it is doing 325mph has the power difference between 325mph and 340mph available for climb. If both planes are doing 300mph the 109 has the power difference between 300 and 325 mph and the P-51 has the power difference between 300 and 340mph available.
The slower the aircraft start out, the bigger advantage the 109 has with it's better power to weight ratio. The faster the aircraft are going the closer the "surplus" or available power for maneuver or climb becomes.


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## Vincenzo (Apr 6, 2012)

time to 20k for 51 8.82 minutes (that with 1150 hp)
time to 6km (19,685) for F-4 6.1 minutes 
time to 5k for 51 1.87 minutes
time to 2km (6,562) for F-4 1.8 minutes
time to 25k for 51 13.77 minutes
time to 8 km (26,247) for 109F-4 9.3 minutes

oh yes the 109F-4 can not climb at S.L. flying to 325 mph, and why should do? and yes the 51 can climb very slowly at S.L. flying to 325 mph


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## drgondog (Apr 6, 2012)

Tomo - if you maintain the same drag on the larger wing (VERY doubtful unless you change from conventional to laminar), both values will go down.

Here is the circular arguement. At max speed, parasite drag is at maximum and induced drag is minimum. When you increase wing area, holding weight/airfoil constant, the you will have a very slight decrease in AoA (a good thing) to maintain the Lift to offset the Weight in equilibrium. On the other hand increasing the wing area, for same airfoil, will increase wetted area - and hence increase parasite drag.

If you increase the wing area by increase the chord and holding the span, you will both reduce AR and possibly change Oswald efficiency for the worse and necessarily increase Induced Drag, along with CDo - a very bad thing at max speed or range. On the other hand, lengthening the chord, even with shorter span, may decrease the parasite wing drag at Mach numbers from say .55 to .65M for net positive benefit. Too much incremental span increase is also a major issue structurally resulting weight increases, starting the circular calcs once again.

You have to play with the variables.

When you increase wing area by holding the span constant and increase the chord, your manuever performance will suffer because the reduced AR and e will necessarily lower the CLmax and increase CDo - which will also affect low to medium speed performance, as an example, as well as maximum operational ceiling


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## Cola (Apr 7, 2012)

davparlr said:


> No.
> 
> In comparing airframes, what is important is the hp used verses airspeed attained. I used this chart because it had a distinct power setting test for the P-51 of about 1150 hp which very close to the Bf-109F hp of 1165. The airspeed of the Spit looks quite small so I am suspect that the hp may be wrong. However, even the much more powerful IX top speed at SL is only about 330, quite a bit lower than the max shown by the chart for the P-51A.
> 
> For any given hp and altitude, the P-51 airframe will substantially out perform the other three aircraft in airspeed. The P-51 airframe is the most aerodynamically efficient airframe of any major propeller fighter of WW2. The Fw-190D-9 is a close second.


 
Ok but then, how do you explain, Mustang Mk.I being 30mph slower with similar power rating like P51A on the deck?
While at that, can you explain what does "the most aerodynamically efficient airframe of any major propeller fighter of WW2", exactly mean?


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## Shortround6 (Apr 7, 2012)

Which engines _EXACTLY_ were used in each aircraft and what boost _LIMITS_ were being used. 

Allisons had a _nominal_ power rating of 1150hp but varied, depending on supercharger gear, on the full throttle height. the -39 engine used 8.80 gears and was good for 11,500-12,000ft (no ram), later engines used 7.48 gears (9,600ft ?) and 9.60 gears (15,000-15,500ft). 
The -39 engine offered 1150hp for take-off and could be over boosted. the later engines had structural improvements and could take more over boost. Depending on the date of the test, WEP settings were not initially approved, an Allison could give 1150 to 1540 (?) hp at sea level (or 1000ft. ) but his varied with the supercharger gear, the low altitude 7.48 gear offering the most _usable_ boost at sea level. 

"aerodynamically efficient airframe" may mean the lowest total drag for it's size. 

A P-26 was more "aerodynamically efficient" than a P-12 but the P-12 paled in comparison to a Lockheed Vega and the P-26 was way behind the Lockheed Orion in efficiency. They all used the same basic engine although the newer planes did get a bit more power. 
Getting low drag by using a small airframe is one thing, getting the same or lower drag while using a bigger airframe is efficiency.


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## drgondog (Apr 7, 2012)

Cola - what do have in mind relative to such low Drag (outside Rutan's wonders) in a reciprocating engine (or turboprop) aircraft that has been designed and flown in production since the P-51B/C/D/K/H?


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## Cola (Apr 7, 2012)

Shortround6 said:


> Which engines _EXACTLY_ were used in each aircraft and what boost _LIMITS_ were being used.


Well, we do know that V-1710-39 (Mustang Mk.I) developed 1150 hp at SL (installed) with boost (Military setting) and we also know V-1710-81 (P51A) developed similar power without boost, but was apparently 30mph faster.
So, you still didn't answer my question, because obviously power was equal and you insisted, that was enough to make comparison.



> "aerodynamically efficient airframe" may mean the lowest total drag for it's size.


It may, but usually doesn't, since "aerodynamic efficiency" mainly refers to L/D ratio.
P51A had a 5% smaller AR and 10% higher wing loading then 109F4, so the actual amount of drag reduction the Mustang's laminar wing produced in relation to higher alphas flown over almost all speeds, makes your claim very dubious, at best.
It's probably the other way around, but I wouldn't speculate at this point.



drgondog said:


> Cola - what do have in mind relative to such low Drag (outside Rutan's wonders) in a reciprocating engine (or turboprop) aircraft that has been designed and flown in production since the P-51B/C/D/K/H?


Mustang was pretty sleek at high speeds.
But as I said, no such thing as "best" airframe in such broad terms.
Airframes that fly good straight, usually suck in turn and the other way around.
All planes are results of a KPP instilled compromises.


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## tomo pauk (Apr 7, 2012)

Mustang I (1 pair of 20mm cannons) was using 1150 HP to make 363 mph at 5100 ft, P-51A (2 pairs of HMGs) was using 1125 HP to make 357 mph at 5000 ft. All data from Mike Williams' site.
The P-51A's engine is using more power to drive it's supercharger, having FTH 2600 ft higher - that explains the 25 (B)HP difference. Giving the P-51A another 100 ft, thus making both planes flying at the same altitude - the speed achieved is within measurement tolerances.

added: The addition of wing racks skews the comparison - P-51/Mustang I was (usualy) without them, wile the P-51A/Mustang II was carrying them on regular basis. The wing racks cost 12 mph, according to 'US 100 hundred' book.


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## parsifal (Apr 7, 2012)

What about the flying conditions and the individual conditions at the time of the tests. The fuels used, the atmospheric conditions, engine wear, the paint job. whether in military condition or clean. There are many variables. Drag can be affected by many factors not seen in the basic drawings. Same for engine power. Engine power outputs can be quite massively affected by seemingly minor, sometimes undetectable variations to its construction. Everything built by human hands works to tolerances, and sometimes those tolerances work to lower or heighten performance by huge margins


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## tomo pauk (Apr 7, 2012)

The 'measurement tolerance' should take care for that.

Claiming this:


> Well, we do know that V-1710-39 (Mustang Mk.I) developed 1150 hp at SL (installed) with boost (Military setting) and we also know V-1710-81 (P51A) developed similar power without boost, but was apparently 30mph faster.


is misleading. 
The -81 was equipped with supercharger tailored for greater altitudes, in order to exploit the advantage (= less drag) of the thin air at higher altitudes. So, above ~16000 ft, the P-51A was really faster than the P-51. Under 15000 ft, the P-51 should be faster - it has 25 HP more (because it's supercharger sucks less power, supercharger drive having 8,80 ratio vs. 9,60 for P-51A). All of this for military power.

All ww2 fighters were using the boost, so the claim that P-51A was developing similar (or any) power without the boost is simply not correct - supercharger was in function all the time.


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## drgondog (Apr 7, 2012)

Cola said:


> Well, we do know that V-1710-39 (Mustang Mk.I) developed 1150 hp at SL (installed) with boost (Military setting) and we also know V-1710-81 (P51A) developed similar power without boost, but was apparently 30mph faster.
> So, you still didn't answer my question, because obviously power was equal and you insisted, that was enough to make comparison.
> 
> *Were you talking to Dave? Shortround and Tomo pretty well answered this question - If I understood your point?
> ...


*

Agreed on the compromises required by the designer - trying to figure out what the Contractor REALLY wants to pay money for.*


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## Shortround6 (Apr 7, 2012)

Cola said:


> It may, but usually doesn't, since "aerodynamic efficiency" mainly refers to L/D ratio.



The L/D ratio relates to the aerodynamic efficiency of the wing, not the airframe as whole. 

Which is the more aerodynamicly efficient airplane, a single seat fighter (with one .50 and one .30 cal gun) that can do 234mph at 8000ft or a single engine airliner with a pilot and 6 passengers that can do 220mph at sea level using the same engine?


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## Cola (Apr 8, 2012)

@drgondog,


> At the end of the day, while HP is the rule of thumb...


 
Exactly and this is why assessments done on the hp basis alone is misleading.
Now, the P51A's engine characteristic, from Shortround6's chart, looks more like Merlin 45 than V-1710-81 a standard engine for P51A and this combination certainly doesn't belong to '41 and comparison against 109F4.
Then, there's the matter of supercharger tuning and propeller, which differs for those two engines and particularly for 109, so again claiming superior drag performance based on different engine/propeller setup is also misleading.
This is why I said 109G-1 would be better comparison to P51A (with Merlin 45) from the chart.

As said, I won't speculate, since assumption is mother of all f*ck-ups.
If you get your hands on measured or manufacturer's data (not computer simulations) and time permitting, we can make a thorough analysis and comparison.
I agree that friction drag was major player in drag at top speeds, but there is also a matter of wetted area, which is higher for Mustang at all speeds (higher alpha and larger size), so for the rest of envelope Mustang wasn't as good lifter, at least theoretically, as 109.


@Shortround6,
look, you said "aerodynamic efficiency" and I told you what does it refer to and it's not Cd/aircraft size...and L/D doesn't refer to wing only, but the whole aircraft.
What you said, Cd/aircraft size is more in line with fineness ratio.


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## drgondog (Apr 8, 2012)

Cola said:


> @drgondog,
> 
> 
> Now, the P51A's engine characteristic, from Shortround6's chart, looks more like Merlin 45, instead of V-1710-81 a standard engine for P51A and this combination certainly doesn't belong to '41 and comparison against 109F4.
> ...



All in - the 51 was faster on the deck at a higher gross weight, had a lower oefficients of total drag, induced drag and lower parasite drag - i did the above calcs in a hurry but you are free to challenge and present your own from the two reports cited.


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## Vincenzo (Apr 8, 2012)

sorry drgondog 363 mph at S.L. with V1710-39?
as i can read in Williams site this is the speed at 5.1k


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## Shortround6 (Apr 8, 2012)

fineness ratio is the comparison of the length of an object (boat, airplane, car) and it's width. While a useful number it does not really describe the coefficient of drag. Two fuselages, each with a length of 48 ft and a diameter (or width/height) of 8 ft will both have a fineness ratio of 6 to 1 even if one is a box with square corners and flat front and flat rear and the other is a gradually tapering ellipse in side view and of circular cross section. 

You can stick a highly efficient wing on a box of a fuselage:







and still wind up with a high drag airplane.


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## davparlr (Apr 8, 2012)

drgondog said:


> All in - the 51 was faster on the deck at a higher gross weight, had a lower total drag, had lower induced drag and had lower parasite drag - i did the above calcs in a hurry but you are free to challenge and present your own from the two reports cited.


 
And this basically demonstrates what I meant by "aerodynamic efficiency". My definition is simply the comparison of horsepower generated to speed achieved. This measures the efficiency of the entire aircraft as system, including L/D, cooling efficiency, etc. and negates any fuel types or compressor operations. Since most aircraft has a SL hp and SL airspeed this is a common point. Just comparing the post '44 P-51B with other similar aircraft, the Spit MkXIV, Fw-190D-9 and the Bf-109K-4 we get the following:

P-51B hp/mph at SL *4.6*, top speed 388 mph, hp 1788 (note: pre-May, '44 P-51B was 4.5, difference was probably just a variable in the aircrafts.)
Bf-109K-4 *4.7*, 376, 1800
Spit mk XIV *5.4*, 389, 2130
Fw190D-9 *5.44*, 386, 2100

Note that the Bf-109K and the P-51B were very similar to each other but the P-51B is a much physically larger aircraft. 

It is important to compare aircraft of similar speed since drag is a geometric progression and this distorts comparison between aircraft with significant difference of top speed.


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## tomo pauk (Apr 8, 2012)

Cola said:


> @drgondog,
> 
> 
> Exactly and this is why assessments done on the hp basis alone is misleading.
> ...



If I may.
Since a picture says thousand words, I've clapped a 'chart' that covers the HP achieved by both P-51's Allisons, plus the Merlin 45. The lines for the Allisons are provided above the FTH, and for Merlin 45 for the comparable altitudes. All lines are without the ram effect, and I did not bothered to convert from BHP to PS, it would make no difference for the lines I've drawn. We can easily see that whatever the performance at altitude the V-1710-81 had over the -39, Merlin 45 was one step ahead. Of interest is that P-51A was faster than P-51 at 20-25000 ft for some 25-35 mph (add 12 mph if the P-51A is not equipped with wing racks), and it's was luck for the LW that it was not equipped with a single stage Merlin from day one.

The Merlin 45 was not the best Merlin available in 1941, being only the 3rd best available Merlin after mid 1942. Compared with those, contemporary V-1710s* were 3rd, or 4th tier, and if we count in the DB-601/605s, V-1710s* were really looking bad. And then we have the plane that, on 'bad' engine, makes some of the competition (boasting the 1st/2nd tier engines) eating it's dust. Perhaps that airplane had great airframe, waiting for the really good engine to become a great performer? 

*talking about single-stage versions, found in the P-39/40/51

Bill, thanks for the D-9 reply.


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## Cola (Apr 8, 2012)

@drgondog,
109G-1 - 700km/h - 7km/23k ft - ~1150 hp/AtA1.42
P51B - 679km/h - 7km/23k ft - ~1270 hp (high and low blower)
Now, what?

@tomo,
forget about Merlin.
My mistake since I didn't figure, that 51A flew with some hybrid Allison...normal -81 was rated at 1200hp/SL, according to manufacturer's table.
Funny detail; plane was specially washed prior to flight. Hardly a wartime maintenance standard.


> and it's was luck for the LW that it was not equipped with a single stage Merlin from day one.


Ain't so.
Luftwaffe had top racers when they needed them.
They didn't bother to go over 700km/h until '43, since they didn't need it and they could hang heavy weapons, at expense of performance.
Most data you got for 109Fs and 109Gs are flown with AtA1.30 and it was '42/'43 (depending on model), when Allied 700+km/h fighters started to arrive in tactically significant numbers, when Luftwaffe lifted AtA1.42, limit.


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## parsifal (Apr 8, 2012)

amazing stuff guys, keep it up, Im sure some consensus will eventually emerge....or is this another sorenism


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## Shortround6 (Apr 8, 2012)

Cola said:


> Now, what?
> 
> Ain't so.
> Luftwaffe had top racers when they needed them.
> ...



Seems to be a bit of a disconnect here. See: 

Kurfürst - Mtt. AG. Datenblatt, Me 109 G - 1. Ausführung

Speed at 7km is 660kph using 1230PS. not 700kph using 1150hp. 

Which one is correct??

and no you don't get 1150hp at 7km using 1.42 AtA and also get 1230PS using only 1.3 AtA at 7km


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## drgondog (Apr 8, 2012)

Cola said:


> @drgondog,
> 109G-1 - 700km/h - 7km/23k ft - ~1150 hp/AtA1.42
> P51B - 679km/h - 7km/23k ft - ~1270 hp (high and low blower)
> Now, what?
> ...


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## drgondog (Apr 8, 2012)

Vincenzo said:


> sorry drgondog 363 mph at S.L. with V1710-39?
> as i can read in Williams site this is the speed at 5.1k



Vincenzo - you are right. I have to go dig up the SL data if I can find it


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## davparlr (Apr 9, 2012)

Cola said:


> Ok but then, how do you explain, Mustang Mk.I being 30mph slower with similar power rating like P51A on the deck?
> While at that, can you explain what does "the most aerodynamically efficient airframe of any major propeller fighter of WW2", exactly mean?


 
I do not understand where you got your information. I looked at every P-51 test that had the P-51 using 1150 hp on the Williams site and this is what I got
1.	North American (NA) test Apr 24, 1940, SL Speed *316 mph*. This was an estimate prior to the development of the P-51 with no engine or power base. The Allison engine on the P-40 at that time was generating 1050 hp, most likely the number used in this estimate and *not a valid comparison*.
2.	NA estimate of the A-36 May ’42, SL speed 345 mph at 1324 hp. *Estmate speed at 1150 325 mph*. Since bombs were estimated aircraft would be estimated with racks. If so 335 mph would be an estimate clean. A-36 is much slower than an equivalently powered P-51 and *should not be included in estimate*. 
3.	P-51 #41-37320 with -39 engine. Test June, ‘42 Speed at 5k ft, 363 mph, *calculated at SL 340 mph*.
4.	P-51 test Dec. ’42. Average of three test aircraft, 343 mph at 5k ft. *Calculated at SL, 328 mph*.
5.	P-51A #43-6007 test Apr ‘43. 5k ft. alt. speed at 1150 hp, 358 mph. *Calculated at SL, 343 mph*
6.	P-51 #41-37320 test Jul ‘43. 4.3k ft. alt. speed at 352 mph. *Calculated at 352 at SL*. *Deleted as high value*.
7.	P-51 #41-37320 Sep ’43. 13k ft. alt. airspeed at 395 mph. *Calculated at SL, 345*.
8.	Mustang I, Apr ’42. 9k alt. airspeed at 350 mph. Calculated at SL, 320. *However, boost is low at 42” verses approved 44”, so will not include in comparison.*
9.	Mustang I, Feb.43. 1k ft. alt. airspeed at 328. *Calculated at 325 mph*.

So, deleting 1. for estimate prior to build and probably wrong engine, 2. because A-36 has a different configuration to P-51, 6. because of highest value, and 8. for lowest values, which should have been eliminated anyway in that it did not generate require hp due to lower boost, *I get the average of 336 mph*. I doubt this is acceptable to you, but it is a rational way to exam data (flight control use a similar algorithm).


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## jim (Apr 9, 2012)

Good work Mr Cola, good work.
So if i understood
drgondog s calculations are using wrong speed (363mph) ,and even this is achieved by a sanded machine with 4 o.50 HMGs, not cannons. What he is trying to accomplish? Also that 51B was 403mph at 38000 ft has to do with the 2 stage supercharger ,not the airframe
Mr davparir can not give tne SL speed but calculates it.But his results look more realistic
All 109s values are on 1,3 Ata. Correct? And had semi retractable tail wheel and no full covered main wheels. And if german factories could achieve good quality construction( similar to the american s) up to 12 km/h could be added according to german documents,at Kurfust site
It seems afterall that Sl speed advantage of early 51s is not that great.
'Airframes that fly good straight, usually suck in turn and the other way around'.( by Cola)
Excellent statement , not confronted yet . Applyies well to P51. 

PS Someone should protect Mr Soren from insults. He is not allowed to defend himself.


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## riacrato (Apr 9, 2012)

drgondog said:


> 109G-1 - 700km/h - 7km/23k ft - ~1150 hp/AtA1.42
> P51B - 679km/h - 7km/23k ft - ~1270 hp (high and low blower)
> Now, what?
> 
> ...


*
Hi drgondog,
I don't know if Cola just wanted to illustrate a point, that if you pick the lower and upper ends of test reports depending on your case you can come up with pretty skewed results. The 700 km/h figure is from the original source though and it stands out from other test reports of that type. One can speculate as to why. From what I read from the chart it is maybe with 1.42 ata (Hoechstleistung is a rather broad term), maybe not corrected for compressibility, but that would be pure speculation and I wouldn't resort to that. It is certainly not the speed flown by a typical G-1 in field conditions, I think everyone will agree on that.

It is an interesting discussion here, I hope that everyone is not just cherry-picking his data to prove his pet is the furriest, though.*


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## Shortround6 (Apr 9, 2012)

I think the 109 figures are starting to head for coulda/shoulda/woulda land. IF the Germasn had A, and done, B and Done C and........the 109 would equal the P51 in drag. 

Are we arguing what could have been or what was? 

And the P-51 was carrying a heavier payload of fuel, weapons and ammo so even if you get the drag of the 109 to equal the P-51 it still doesn't equal the efficiency of the _airplane_ as a whole. Efficiency in this case being defined as power required to move a certain payload at a given speed. Or rephrased, hp needed to move 100pounds of payload at 325mph at sea level.


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## Vincenzo (Apr 9, 2012)

Davparl
i've some trouble with your 6. calculation
checking original the 4.3 speed is 369.5 mph


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## drgondog (Apr 9, 2012)

jim said:


> Good work Mr Cola, good work.
> So if i understood
> 
> *http://www.wwiiaircraftperformance.org/mustang/p-51-37320-test.pdf*
> ...



Protect yourself, I can handle myself from your insults.

Regards,

Bill


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## Cola (Apr 9, 2012)

@drgondog,
you're probably right, but...
I say probably, because I calculated with overall pressure (dynamic + static) for 700km/h @7km as ~0.52 kg/cm^2, which is negligible, according to this chart.
Also Rechlin flight test, lists DB605A's power as 1355 hp, at 5.7km, which corresponds with my calculations.
However, it's still unclear where is that pressure measured and which pressure line corresponds with what speed and calculated values from Datasheets you linked, may be correct indeed.

A few more points, though...
First, I've noticed you substitute wing area in drag formula and you can't do that if you wanna calculate absolute drag or comparable drag coefficients, for different aircraft.
The reason is that wing area value disregards fuselage component of drag and you can have differently aspected wings within same area, both of which produce misleading results.
Second, there are two main propeller parameters, exit velocity and the air mass.
Since, propeller's thrust equals air mass times exit velocity, you end up with two types - fast (smaller mass over faster speed) and slow (larger mass over slower speed).
So, you can have equal nominal thrust, but different net thrust lapse over the speed curve and "fast" type can yield more net thrust on the right hand part of the envelope, producing faster plane.
I didn't have time to examine all propellers involved, but I hope I will, if I get the time.

Now as for the top speeds, they're not bogus, but flown at E-stelle in Rechlin.
Here's the AtA1.3 (which we know for sure), flight record for 109G-1 and I already linked AtA1.42, one.
Derived graph
109G-2, a model without pressurized cockpit, flew 666km/h at AtA1.30, so it's a fair guess it surpassed 700km/h at AtA1.42 and not marginally.

To conclude.
Calculated power for Kurfurst's datasheets, still remains open though and I'd appreciate any input toward solving that question, although I suspect them being correct.
(would be helpful if someone could translate this chart's text only, but in the context)

Cheers


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## drgondog (Apr 9, 2012)

riacrato said:


> Hi drgondog,
> I don't know if Cola just wanted to illustrate a point, that if you pick the lower and upper ends of test reports depending on your case you can come up with pretty skewed results. The 700 km/h figure is from the original source though and it stands out from other test reports of that type. One can speculate as to why. From what I read from the chart it is maybe with 1.42 ata (_Hoechstleistung_ is a rather broad term), _maybe_ not corrected for compressibility, but that would be pure speculation and I wouldn't resort to that. It is certainly not the speed flown by a typical G-1 in field conditions, I think everyone will agree on that.
> 
> *Hi Riacrato - The reason I pick SL for the calcs when I can find them is to strip multi stage supercharging questions out of the calculations, same with 5-6000 feet as all of these engine hp tables are from SL bench tests - thus lower 'probable' error in the Hp extracted for speed runs.
> ...




*Last but not least. None of the discussions regarding speed at any altitude are especially meaningful UNLESS the following data is clearly presented in the report;

1. Calibrated airspeed, corrected for Mach No compressibility effects.. not terribly significant on the deck but extremely important as airspeed at altitudes are presented. 
2. Gross weight of the tests - mandatory to calculate Induced Drag which is mandatory to calculate parasite drag from the free body equation at equilibrium Thrust = Total Drag = Parasite + Vortex (incl compressibility) + Induced + Wave Drags
3. Horsepower - the most questionable of the Test assumptions, but necessary for Thrust assumptions
4. Special conditions (like 400 grit sandpaper on P-51A tests which I did not use) or 20mm cannon barrels versus 50 caliber recessed in wing). The P-51 four cannon configuration is a Significant drag feature over four recessed 50 cal, ditto underwing gondolas, ditto external bomb racks - all contributing significant increases over base airframe.
5. Notes in the report about balky carburation or engine performance.*

I missed the 5K vs SL data point but have recalculated and will put up the revised P-51 w/-39 Allison. Two points: the difference did increase flat plate drag (which I should have picked up immediately) from 3.5 to 4.06 sq ft. And two, the Parasite and induced drag of the 51 is Still (both) lower than the Me 109F4 as Uncorrected data presents AND the 51 in that report is excessively draggy over 4 gun 50 config but I did use the two 20mm cannon config at the lower gross weight of 8100..


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## GregP (Apr 9, 2012)

Who protected anyone else when Soren was insulting them?


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## davparlr (Apr 9, 2012)

Vincenzo said:


> Davparl
> i've some trouble with your 6. calculation
> checking original the 4.3 speed is 369.5 mph


 
Thanks, you are right. I had a typo. I did delete that anyway from my average because it was the high value.


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## Shortround6 (Apr 9, 2012)

Something on the German Charts is that there may (or may not, I don't read German) be a difference between the power chart supplied by the engine maker and the power as installed and used in the Airplane. British and American engine makers supplied power charts _without_ ram effect being figured in and let the airframe manufactures or government figure out the actual power at height using ram.

The difference is evident in many of the Charts on the Spitfire performance site where the "full throttle" height of an airplane does not correspond with the full throttle height given in any charts/specification by the engine makes and that full throttle height in level flight is 2-4000ft higher than the full throttle height in a climb. 

A Spitfire I will be able to have a higher full throttle altitude in level flight than a MK I Hurricane because the extra speed allows the RAM effect to maintain the needed inlet pressure that much higher. 

At sea level ram is not particularly important because the superchargers can supply more air than the engine can use and the engine are throttled back. at 6-8000 meters ram in level flight can allow either a full throttle height 2-4000ft higher or, in effect shift that sloping line upwards (or to the right) by 50-150hp (or by the altitude difference).

Please note on teh German charts that the points noted as 1.42 or 1.30 at 5-6000meters are the highest points at which that pressure is maintained and as the plane/engine climbs higher and that power line declines the engine is no longer running at 1.42 or 1.30 AtA. Using Ram would account for the 109 having more power at 7000 meters than the engine chart says.


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## drgondog (Apr 9, 2012)

Cola said:


> @drgondog,
> you're probably right, but...
> I say probably, because I calculated with overall pressure (dynamic + static) for 700km/h @7km as ~0.52 kg/cm^2, which is negligible, according to this chart.
> Also Rechlin flight test, lists DB605A's power as 1355 hp, at 5.7km, which corresponds with my calculations.
> ...



I'm about done. Pick what you wish and leave the rest.


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## cimmex (Apr 9, 2012)

As an engineer I used to say: Tell me the result you want and I’ll find the right calculation to present the proof....
cimmex


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## tomo pauk (Apr 9, 2012)

Cola said:


> @drgondog,
> 109G-1 - 700km/h - 7km/23k ft - ~1150 hp/AtA1.42
> P51B - 679km/h - 7km/23k ft - ~1270 hp (high and low blower)
> Now, what?
> ...



Beim-Zeugmeister shows a top speed for the Bf-109G-1 to be 700 km/h, plane being equipped with 2 LMGs, 1 x MG-131 (firing through the prop!) and 2 x MG-151/20 in the wings. So we have the mysterious G-1 with 5 gun's openings achieving 700 km/h. Neither such a high speed figure, nor the 670 km/h for the Bf-109F-4 is to be found in any flight test charts. 

The -81 was not a 'hybrid' type. The V-1710 subtypes with 9,60:1 supercharger drive ratio were mounted on P-51A, P-39M/N/Q, P-40M/N, from late 1942/early 1943 on. In 1943 the production/installation of the V-1710s with 8,80:1 ratio was discontinued.

So, 'Luftwaffe lifted the 1,42 ata limit'? If your engine is fit to deliver the declared output, why would you limit that during the major war? Did they just decided that they don't like the limit, or it took Marseille's death to see that the 1942-vintage 605 has issues, limit the engine, work hard to find the culprit, manufacture the needed/better parts, install the de-bugged engines and THEN to lift the limit for the DB-605? The BMW-801s were experiencing the same limitations, both in fighter and bomber installations. 

The Bf-109 that was able to fly faster than 700 km/h was the K-4, and that's second half of 1944, not 1943.
added: despite being a fine interceptor, the K-4 still carried far less of armament weight (if it's to fly above 700 km/h) and less than half of the fuel - the usability, an important category of a weapon of war, was far smaller than of the contemporary P-51.


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## parsifal (Apr 9, 2012)

GregP said:


> Who protected anyone else when Soren was insulting them?



You note the similarity too I see


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## drgondog (Apr 9, 2012)

cimmex said:


> As an engineer I used to say: Tell me the result you want and I’ll find the right calculation to present the proof....
> cimmex



In the US you would be a civil litigation trial attorney. As engineers we still try to run the calcs and let them tell us the result.


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## Shortround6 (Apr 9, 2012)

In the US the joke is when looking for an accountant ask him how much 2 + 2 is. When you find one that says "what did you have in mind" you know you have found your man


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## davparlr (Apr 9, 2012)

drgondog said:


> In the US you would be a civil litigation trial attorney. As engineers we still try to run the calcs and let them tell us the result.


Except when it comes to cost. All the B-2 managers were sent to take a course in cost estimating computer program which the government was levying on all subcontractors, Price M or something. I remember sitting in the class while the instructor was presenting his explanations and I was busy figuring out how I could manipulate the assumptions to get the number I wanted. I knew better than any machine how much it was going to cost to deliver my product.


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## CobberKane (Apr 9, 2012)

Enough about P51s already! I propose that in debating the best airframe (and fighter) of WWII we apply the following yardsticks.

1.Economy of construction and ease of service (okay, the Mustang does look pretty good from this perspective, I admit, but so do the Bf109 and Hawker Hurricane)
2.Historical contribution to the course of the war (Mustang looking even better... as do the other two)
3. Success in air to air combat defined in number of kills 

Mustang takes third place behind the Bf109 and Hurricane.


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## DerAdlerIstGelandet (Apr 10, 2012)

GregP said:


> Who protected anyone else when Soren was insulting them?



We did. We removed the problem...


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## Cola (Apr 10, 2012)

drgondog,
How do you figure friction and induced drag components?
Using 50%, 30% of total drag, respectively?



> and wing area is THE common frame of reference


I know, but it still doesn't make it right, since you can have Mustang's, or Liberator's fuselage in between...the results will differ.
You can use it when working with wing increments on the same fuselage, to illustrate differences.



> as the induced drag increment due to rounded tip versus the 51 tip/chord ratio sets up a reasonaly close spanwise lift distribution, the aspect ratios are close


Well that's a matter of perspective and it may be reasonably close compared to Mirage III, but makes significant difference between these two models and their respectful performance.
So, as we know Mustang was less draggy at top speeds, we also know that it probably produced more of induced drag, throughout the rest of the speed envelope.
It's a trade off and my original point, regardless of actual amounts of each and you don't measure L/D ratio only on top speed, but along the whole envelope when assessing "airframe efficiency".



> Once again - anything at .5-55M during WWII introduces noticable instrumentation errors and there is no mention of algorithms or even attempts to make TAS corrections...


How's so?
These guys do it..."Anzeige" - IAS, "Wirklich" - TAS
Also, I found on several places, manufacturer/Luftwaffe listing performance on a standard (ISA?) day, so there was some standardization, back then.



> only the 'real Hp' delivered is interesting because that is the basis for free body diagram to solve for gross Drag. Yes?


I agree, but "real Hp" in that case vary with propeller and its net thrust and you can't draw conclusions about aerodynamics from that.
It's like comparing turbojet and turbofan of the same thrust installed on the same airframe and then trying to blame aerodynamics, when turbofan comes second at top speed.
Also, there's a point of trim drag, which isn't a sole property of aerodynamics, but weight distribution as well and is one of the major players at top speeds, too.

As for the critical Mach number, it seems that general consensus is it didn't occur until M.7+, which generally wasn't a problem in level flight and I don't see what does the compressibility has to do with anything...what do you mean?


@tomo,


> The -81 was not a 'hybrid' type. The V-1710 subtypes with 9,60:1 supercharger drive ratio were mounted on P-51A...


Well Allison lists V-1710-81 as a 1200hp/3000 RPM/SL - 1125hp/3000RPM/FL146 and the one from the chart develops almost 1500hp.
Also, in the drgondog's link, there's an item that mentions an experimental carburetor being fitted.



> If your engine is fit to deliver the declared output, why would you limit that during the major war?


To conserve it, a major item in any military of any age.



> The Bf-109 that was able to fly faster than 700 km/h was the K-4, and that's second half of 1944, not 1943.
> added: despite being a fine interceptor, the K-4 still carried far less of armament weight (if it's to fly above 700 km/h) and less than half of the fuel - the usability, an important category of a weapon of war, was far smaller than of the contemporary P-51.


Ah ok...but are we making a religion now, or follow the body of evidence?
Now, as for your comment of the weapons...
K-4 had 2x15mm cannons and 1x30mm cannon and not Mk108, but its big brother Mk103.
Also, K-4's cannon battery was fixed in the nose, making it both very precise and accurate (engine used as a recoil absorber and no necessity for rifling convergence), so you don't get to compare it linearly to other, wing armed, planes.


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## parsifal (Apr 10, 2012)

CobberKane said:


> Enough about P51s already! I propose that in debating the best airframe (and fighter) of WWII we apply the following yardsticks.
> 
> 1.Economy of construction and ease of service (okay, the Mustang does look pretty good from this perspective, I admit, but so do the Bf109 and Hawker Hurricane)
> 2.Historical contribution to the course of the war (Mustang looking even better... as do the other two)
> ...



Hello Cobberkane and welcome

I applaud your intent to try and get some air under the wings of this debate, and i am not about to embark on a tirade to denigrate any of the three aircraft that you selected. All three in their own right were truly great aircraft that contributed very greatly to the course of the war. but whilst I agree with the laudable objectives, I think in delivery your post falls at the starting gun. 

Why do you think the Mustang comes in behind the other two? You raise three main points in your post which I comment on as follows



> 1.Economy of construction and ease of service (okay, the Mustang does look pretty good from this perspective, I admit, but so do the Bf109 and Hawker Hurricane)



The 109 was cheaper to build but not by much, and it suffered a much higher attrition rate to the Mustang, and a lower serviceability compared to the Mustang. Mustangs suffered about 18% attrition rates per month to all causes from mid-1943 to the end of the war, compared to about 37% per month for 109s based in Germany in that same period, and close or above 50% outside of Germany (mostly Eastern Europe) which went up or down depending on the season. There were many extraneous reasons for that, but your statement was a blanket "its cheaper to run a 109 unit than a Mustang unit"....not true, whatever the reason, the Germans had far higher wastage of aircraft, and therefore far higher costs to maintain a given unit equipped with a 109 over a Mustang. 



> 2.Historical contribution to the course of the war (Mustang looking even better... as do the other two)


 
This is a highly subjective statement, and has the potential to attract endless argument and counterrargument. I obviously dont agree with the implication present in your comment....."the Mustang had a lower historical contribution to the war than either the 109 or the Hurricane". if that is your opinion, I disagree pretty strongly. All three made major contributions, but of the three, it was the mustang that made the most, followed closely by the hurricane. The only reason the hurri is of lesser importance than the P-51 is because it did not have a big role in the Pacific, whereas the P-51 did.

For reasons not entirely related to the aircraft, it was the Mustang that forced the wholesale redeployment of German fighter assets back to germany, leaving their frontline armies under protected. The 109 equipped fighter units of the LW, along with all other fighters, were unable to stem the carnage being meted out on Germany, and lost in the order of 5 or 6 fighters for every fighter they shot down. There were many reasons of which those that relate to the actual aircraft themselves are relativbely minor, but you did not qualify your statement in that way. 
I would argue that of the three types, the Mustang had the greatest impact on the outcome of the war ( in all TOs and in all the roles it was used for) 



> 3. Success in air to air combat defined in number of kills



Without a doubt, the 109 has this part of the market cornered, yet the numbers I have seen take a withering beating when you look at the figures closely. on the eastern front, some in this place have tried to claim that the 109 was responsible for shooting down at least 25000 IL-2s. Wrong. A closer estimate is about 1500-3000 1943-5, with about as many again prior to that. A high kill ratio, to be sure, but a drop in the ocean compared to what the russians were able to put in the air overall, and gained at a pretty hefty price in lost machines overall. The 109 was the most prolofic shooter of the war....it was also at least one of the most prolific losers of the war.......thats the problem with fighters.....to shoot aircraft down, you lose a whole bunch more the moment you take to the air whatever your inherent advantages. As the Germans found out to their cost, fighters dont win wars, they may reduce your losses, but they cant win wars, and when your opposition can swamp your defences, all you are doing by putting your fighters up is increasing their costs whilst also increasing your own. Fighters can plow the ground for your bombers, they can increase the losses for your opponent, but they cannot except in exceptional circumstances in you air superiority or air supremacy, and thats what was needed to win wars.


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## Cola (Apr 10, 2012)

CobberKane said:


> Enough about P51s already!



Why?
Personally, I find it very interesting.
You get to understand drives behind particular construction decisions and their consequences on the flight behavior, etc...well, if you're interested in that kind of stuff.


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## drgondog (Apr 10, 2012)

Cola said:


> drgondog,
> How do you figure parasite and induced drag components?
> Using 50%, 30% of total drag, respectively?
> 
> ...



Do the math,then challenge my assumptions, rather than assume conventional wisdom based on flight experience or what you have read. I make mistakes in math when I don't much care if someone is checking for grades.


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## Shortround6 (Apr 10, 2012)

Cola said:


> Well Allison lists V-1710-81 as a 1200hp/3000 RPM/SL - 1125hp/3000RPM/FL146 and the one from the chart develops almost 1500hp.
> Also, in the drgondog's link, there's an item that mentions an experimental carburetor being fitted.



And speed was recorded at both 1200hp/sea level rating (Military power) and the 1460-1480hp level (WEP) just make sure the manifold pressure is included in the speed listing to be sure which is which. 



Cola said:


> To conserve it, a major item in any military of any age.



"Conserving" the engine, when it may give a military advantage, is just as poor a policy as flagrantly blowing up engines to no purpose. 

How many allied planes escaped or German pilots died while "conserving" their engines during this period?




Cola said:


> Ah ok...but are we making a religion now, or follow the body of evidence?
> Now, as for your comment of the weapons...
> K-4 had 2x15mm cannons and 1x30mm cannon and not Mk108, but its big brother Mk103.
> Also, K-4's cannon battery was fixed in the nose, making it both very precise and accurate (engine used as a recoil absorber and no necessity for rifling convergence), so you don't get to compare it linearly to other, wing armed, planes.



The "body of evidence?" ROFLMAO

Got one shred of proof (like a photo) that the K-4 _*EVER*_ carried the guns you list into the air? Or even had them fitted in a firing trial on the ground?


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## Milosh (Apr 10, 2012)

Cola said:


> Ah ok...but are we making a religion now, or follow the body of evidence?
> Now, as for your comment of the weapons...
> K-4 had 2x15mm cannons and 1x30mm cannon and not Mk108, but its big brother Mk103.



Oh dear not that myth, again.


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## parsifal (Apr 10, 2012)

drgondog said:


> Do the math,then challenge my assumptions, rather than assume conventional wisdom based on flight experience or what you have read. I make mistakes in math when I don't much care if someone is checking for grades.



DG you have the patience of Job and the wisdom of Solomon. Keep it up, you are doing fine.

People may not understand or agree with you, but anyone who discounts your knowledge of things flying is ill advised in my opinion


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## tomo pauk (Apr 10, 2012)

SR6 and Milosh have covered the stuff, not too much for me to post. 

The carburetor was actually one of the things that made single stage Merlin better than the single stage V-1710s. Those were featuring a carby with smaller throat area than Merlin (24,4 sq in vs. 38,3 sq in for s.s. Merlin). The net loss was easy to see wen comparing the altitudes where the 1100-1125 HP were achieved - Merlin 45 20 series were better for 3-4000 ft, vs, the late 1942 and on Allisons (ca. 18500 vs. 14,5-15,5 kft; all without ram effect). You can note that late war P-39 and P-40 were equipped with V-1710s that have had an almost 1000 ft altitude advantage vs. engine of the P-51A (15,5 kft vs. 14,6 kft), so any 'experiment' is excluded. The 15,5 kft was perhaps the highest altitude the single stage, single speed V-1710 was capable, for power of at least 1125 HP (maybe water injection would help, hopefuly someone could chime in with better assessment on this?).

Hi, CobberKaine,



> Enough about P51s already! I propose that in debating the best airframe (and fighter) of WWII we apply the following yardsticks.
> 
> 1.Economy of construction and ease of service (okay, the Mustang does look pretty good from this perspective, I admit, but so do the Bf109 and Hawker Hurricane)
> 2.Historical contribution to the course of the war (Mustang looking even better... as do the other two)
> ...



This is about the best AIRFARME for single engine fighter (either in prototype phase, or those in service), not for the best FIGHTER, nor for the one that made the most kills. We have plenty of the 'best fighter' threads, check them out post there if you wish. As for this thread, you can check out the 1st post here to see what is looked after. You can start the thread at your liking, too.


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## davparlr (Apr 10, 2012)

parsifal said:


> DG you have the patience of Job and the wisdom of Solomon. Keep it up, you are doing fine.
> 
> People may not understand or agree with you, but anyone who discounts your knowledge of things flying is ill advised in my opinion



This is a post about *drgondog*. I agree whole heartedly. Obviously a man with loads of hands on experience in the aero world.


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## jim (Apr 10, 2012)

You forgot to credit him with the objectivity of Solomon as well. Or you kept that charisma for yourself ?


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## DerAdlerIstGelandet (Apr 10, 2012)

Lets not turn this thread into a pissing match with insults. This is not a kindergarten. 

So far this thread has been really good, with opposing ideas discussing the topic peacefully.


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## parsifal (Apr 10, 2012)

jim said:


> You forgot to credit him with the objectivity of Solomon as well. Or you kept that charisma for yourself ?



There is no such saying and no i dont keep that "charisma" for myself. Neither do i give it to you, which is what I suspect is really galling you. I am at a bit of a loss why you would want to attack me on this thread Jim, as I am not denigrating the me 109. I think it was a fantastic aircraft, and a great airframe. This whole debate about the Mustang started because of adverse comments from yourself. You are obviously upset because a lot of people dont agree with you, and are displaying knowledge on the subject that is obviously showing that initial position to be unfounded. I am not speaking of myself. In my opinion you should be appreciative of the time, patience and wisdom being lavished on you, for your sake, but the best you have to offer is cabal and inflammatory rhetoric.

You have made some contribution to the debate, fair enough, but people have either found fault, or simply disagreed with it. thats fair enough as well. You can take the information, or reject it, its entirely up to you. You can bring additional information or opinion to the debate, which is welcome as well. But you may not bring insult and ill temper, as neither can I or anyone else.

So, do you have wisdom, opinion or knowledge that proves or suggests the 109 to be a superior airframe and/or the Mustange not? I would genuinely like to know why you believe the 109 to be such a vastly superior airframe and the Mustang so inferior, even if that means transgressing a little from the topic parameters and just telling why its such a superior machine.

My reasons for believing in the Mustang are related to its abaility to take on the 109, defeat it, but do it at ranges that other aircraft of the same role could never hope to achieve. in my opinion that makes the Mustang an exceptional aircraft.


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## davparlr (Apr 10, 2012)

jim said:


> You forgot to credit him with the objectivity of Solomon as well. Or you kept that charisma for yourself ?



I think Solomon was wise, not necessarily objective.


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## Vincenzo (Apr 10, 2012)

drgodong i tried to understand your formulas in 138th post in this thread (so for do calculation for others fighters). but i've a data problem the wetted area, there are some on line sources for this data?
and a logical trouble the thrust formula .85*Powerhp*550/(speedmph*1.467) following this more a plane is slow and more has thrust, this is right? 
my physics study are too far in the time and limited (only first 2 years of high school) for help me


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## CobberKane (Apr 10, 2012)

b


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## drgondog (Apr 10, 2012)

Vincenzo said:


> drgodong i tried to understand your formulas in 138th post in this thread (so for do calculation for others fighters). but i've a data problem the wetted area, there are some on line sources for this data?
> and a logical trouble the thrust formula .85*Powerhp*550/(speedmph*1.467) following this more a plane is slow and more has thrust, this is right?
> my physics study are too far in the time and limited (only first 2 years of high school) for help me



Vincenzo - a couple of years ago I put the Lednicer VSAERO computer simulations on this site and I believe Tomo found them and presented the wetted area from the near last page of the report. Lednicer developed all the lines and airfoils from the actual data from NAA Drawings and consultation with the key aerodynamicist (having a senior moement - can't recall his name - not Schmeud). Go back to ~ page 8 of this forum but also go the Mustang Data section in the forum archives.

And yes, the Thrust does increase as V decreases, as counter intuitive as it seems, but be careful about accepting the equation unless you carefully examine propeller performance ..


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## CobberKane (Apr 10, 2012)

parsifal said:


> Hello Cobberkane and welcome
> 
> I applaud your intent to try and get some air under the wings of this debate, and i am not about to embark on a tirade to denigrate any of the three aircraft that you selected. All three in their own right were truly great aircraft that contributed very greatly to the course of the war. but whilst I agree with the laudable objectives, I think in delivery your post falls at the starting gun.
> 
> ...




Okay, I'll admit it - I was being a little tongue in cheek. My intention was to give the 109, P51 and Hurricane a draw in the first two gatagories (ease of construction, historical contribution) but rate the Mustang third in air to air kills, which I think is historically correct. My point being that the outcome of the comparison depends on the criteria we use - how else could you assert that the Hurricane had a 'better' airframe than the Mustang, an aircraft a generation more advanced?
I don't think I asserted that the Hurricane's historical contribution was better than the Mustangs, but now you mention it i think i could make a case for it. The Hurricane won the Battle of Britain for the RAF. Without the Hurricane, Operation Sealion probably would hace gone ahead. With the UK off the board Barbarossa probably would have succeeded - game over. Everything you say about the Mustang is true, but it wouldn't have been in any position to make the contribution it did without the preceeding heroics of the Hawker Hurricane.


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## CobberKane (Apr 10, 2012)

Cola said:


> Why?
> Personally, I find it very interesting.
> You get to understand drives behind particular construction decisions and their consequences on the flight behavior, etc...well, if you're interested in that kind of stuff.



Yeah, yeah - I know....It's just that sometimes I think you could start a thread on Jessica Alba's undies and three posts later we's all be talking about P-51s! I am reminded of CS Lewis' criticism of Tolkein - "Oh God, not another elf!"
Maybe I just need to get out more.


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## parsifal (Apr 10, 2012)

CobberKane said:


> Yeah, yeah - I know....It's just that sometimes I think you could start a thread on Jessica Alba's undies and three posts later we's all be talking about P-51s! I am reminded of CS Lewis' criticism of Tolkein - "Oh God, not another elf!"
> Maybe I just need to get out more.




I promise if you start a thrread on her underwear, I will not mention P-51 even once


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## CobberKane (Apr 10, 2012)

parsifal said:


> I promise if you start a thrread on her underwear, I will not mention P-51 even once



Okay, but this is probably going to get me banned...


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## parsifal (Apr 10, 2012)

what were we talking about? i forget.....


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## Vincenzo (Apr 11, 2012)

drgondog said:


> Vincenzo - a couple of years ago I put the Lednicer VSAERO computer simulations on this site and I believe Tomo found them and presented the wetted area from the near last page of the report. Lednicer developed all the lines and airfoils from the actual data from NAA Drawings and consultation with the key aerodynamicist (having a senior moement - can't recall his name - not Schmeud). Go back to ~ page 8 of this forum but also go the Mustang Data section in the forum archives.
> 
> And yes, the Thrust does increase as V decreases, as counter intuitive as it seems, but be careful about accepting the equation unless you carefully examine propeller performance ..



thanks for the clear 
i think you missinterpreted my first point i did not trying to check your data i was looking for data (wetted area) for others fighters.


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## davparlr (Apr 11, 2012)

Based on the initial premise,


> In other words, this time on we should discuss the capabilities of the airframe, independently from the engine it was mounted on it. What designer/manufacturer got it best? The capabilities to be accounted for are "upgradedeability", structural strength, capacity for decent firepower fuel tankage, suitability for engines different that the original, adaptability to work as bomber and/or reccon plane, pilot protection, ability to lend itself for the mass production etc. The carrier-borne planes yield no points for such capabilities.



I would pick the following airframes based on potential air combat capabilities, growth potential for power, and size adequate for weapons and fuel upgrades.

1. P-51 Overall aircraft efficiency offered performance and size and strength provided combat growth.
2. Fw-190 for similar capabilities
3. F4U. Big and powerful with great potential in many roles.
4. Typhoon (and its follow-on designs, the Tempest and Sea Fury). Had to evolve but seems to be a great design 

Even though I rated each, I think one could mix up the numbers and not lose much, if anything, no matter how it turned out.

In my opinion, while outstanding performers, both the Spitfire and Bf-109 were limited by their size to effectively expand to different roles.


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## drgondog (Apr 11, 2012)

Vincenzo said:


> thanks for the clear
> i think you missinterpreted my first point i did not trying to check your data i was looking for data (wetted area) for others fighters.



Well - he also analyzed the Spit IX and FW190D-9 and presented those full surface areas also. The references for all wetted areas were also presented. The wetted area for the 109G according to Hoerner was 590 sq ft.

As always context is important. In considering friction drag (or profile/form/vortex drag) you have to ask nagging questions like how much of the surface is in the 'Laminar flow' region, versus full blown turbulence - or where on the wing does the boundary layer separate enough that average surface roughness behind the 'datum' for the adverse pressure gradient start?

So both the wing and total areas provide context when looking at total frag versus lift related drag - and we aren't anywhere close to looking at lift of the fusleage/wing combination.. 

I looked at a lot of Soviet fighter types (Mig 15, 17, 19 21, etc) at Nellis AFB and was amazed at the gaps (some and not consistently in same specifc area) between sheet metal skins, for example, in the regions aft of the wings - an area you could expect a lot of vortex drag and little laminar flow. On purpose? I don't know.


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## tomo pauk (Apr 11, 2012)

I'm not following you here:



> and my point was that you can't linearly compare number of barrels and ROF, for 109 and winged installations, in response to tomo's assertion.


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## tomo pauk (Apr 11, 2012)

Hi, David,

The thread covers the 1941, so we should divide the airframes in service from the airframes in prototype phases. So maybe the Fw-190 should be the 1st choice here (it is in service), and along the prototype/pre-series fighters I hold the P-51 in the high regard. 
The Typhoon features rather different wings vs. Tempest, a notably different fuselage, so it should be regarded as a separate entry - the late war Hawkers are way out of this thread. Typhoon was unable to provide the RAF with a fighter of greater performance over most altitudes vs Spitfires with two-stage engines (tick wing was flatly a wrong choice), the combat range was found wanting, the tail needed reinforcement. I'd rate Spitfire as a far better airframe.


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## tomo pauk (Apr 11, 2012)

For some reason, the post made at 7:11 is listed the one at 6:11 (post #192), so I'll post again:

I'm not following you here:



> and my point was that you can't linearly compare number of barrels and ROF, for 109 and winged installations, in response to tomo's assertion.


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## Cola (Apr 11, 2012)

Shortround6 said:


> And speed was recorded at both 1200hp/sea level rating (Military power) and the 1460-1480hp level (WEP) just make sure the manifold pressure is included in the speed listing to be sure which is which.



Good point.
No argument there, since it explains stuff.



> "Conserving" the engine, when it may give a military advantage, is just as poor a policy as flagrantly blowing up engines to no purpose.
> How many allied planes escaped or German pilots died while "conserving" their engines during this period?



Or it just tells you, that "military edge", as you call it, wasn't needed in relation to price, in observed timeframe.
Again, in reality these things are called contracted lifetimes and are expressed in working hours, at pre-set load.
So, the goal of manufacturer is to produce contracted number of HP over a pre-set lifetime.
Obviously, the engine can give significantly more power, but at the expense of lift time and maintenance.
Now, I won't speculate on Luftwaffe's decision to limit the engine performance, but we do have evidence that it was available as early as in '41 (as per links I've provided), so you're free to assume OKL was a bunch of irresponsible cowboys, but I'm more inclined to think, they didn't really need it at that time.
Ofc, I got no proof for either, but anyone that ever served any kind of army, will tell you pretty much the same thing.



> The "body of evidence?" ROFLMAO



Now, this is pretty immature response, because you're ROFLMAOing at Mr.Christopher Chant and he gets payed for what he writes. You?
He may be wrong though and I can agree that such a configuration was comparatively rare, but even so 109G's standard battery was deadly for a fighter sized aircraft, due position and construction and my point was that you can't linearly compare number of barrels and ROF, for 109 and winged installations, in response to tomo's assertion.
If you have objections on that...let's have them.



> Got one shred of proof (like a photo) that the K-4 _*EVER*_ carried the guns you list into the air? Or even had them fitted in a firing trial on the ground?


No, but neither have you for the contrary and I'm more inclined to believe official publications, than forum myths.

*@drgondog*,


> None of the above. I thought I presented Induced Drag of both the 109 and 51 earlier.


No idea, what you think you showed, but this is how this works in real world...(no IIRCs or assumptions):

Aircraft:

Mustang P-51A*
3084 kg - airframe
300 kg - fuel
100 kg - pilot
OW = 3484 kg

Bf109F-4*
2391 kg - airframe
300 kg - fuel
100 kg - pilot
OW = 2791 kg

(*I'm ignoring ammo, oil and other expendables due time/research constrains)


Flight conditions:
crusing speed: 500 km/h TAS (139m/s)
dynamic pressure: 11.78 kPa ISA
Altitude: deck (static pressure 101 kPa ISA)

Coefficient of lift:
Cl (P51A) = 0.134
Cl (109F4) = 0.144
(if you got Cl/alpha charts, you can figure alphas)

Induced drag coefficient:
Cdi (P51A) = 0.00097e^-1
Cdi (109F4) = 0.001e^-1

Induced drag:
Di (P51A) = 247e^-1 N
Di (109F4) = 190e^-1 N

Note, I expressed induced drag in a function of Oswald number.
Also, I gave Mustang 300 kg of fuel, out of 500kg (nominal internal capacity) only, while 109F4 got full internal tanks and if you wanna calculate both planes in loaded clean configuration (couldn't find reliable and verifiable data for P51A), you'll get in the 40+% neighborhood difference in induced drag.
Do you really need calculations to figure this out?

Now, as for the formula for power as basis for the rest of your story I already made a comment on prop's thrust lapse.
So, the assumption that 51's airframe is less draggy by "this" much, than 109's, while ignoring the 109 might have more draggy propeller, is well, another assumption.

Finally, the CG position isn't really an aerodynamic property.
In an airframe with constant aerodynamics features, CG point will shift as the expendables get spent (fuel/ammo/whatever) and your trim (drag) will change correspondingly.
So, the same airframe with same power has different top speeds without changing power or aerodynamic features for different trim settings and this is particularly pronounced at top speeds.
Hope, we're on the same page now.

Cheers


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## drgondog (Apr 11, 2012)

Cola said:


> *@drgondog*,
> 
> No idea, what you think you showed, but this is how this works in real world...(no IIRCs or assumptions):
> 
> ...


 
I have the distinct feeling you are looking for pages to be on - but I am eqally sure we 'won't be on the same page'.


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## drgondog (Apr 11, 2012)

Cola said:


> P51A had a 5% smaller AR and 10% higher wing loading then 109F4, so the actual amount of drag reduction the Mustang's laminar wing produced in relation to higher alphas flown over almost all speeds, makes your claim very dubious, at best.
> It's probably the other way around, but I wouldn't speculate at this point.
> 
> *For the examples you just set, at 310mph with 51A GW =7682 pound, 109F at 6154 pounds the respective wing loadings were
> ...



Where is the 5% 'extra' for the P-51A? The P-51D AR was 5.9 even that represents only 1.5% difference


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## drgondog (Apr 11, 2012)

parsifal said:


> Got question to do with the hypothertical though DG. What would be your estimates of Mustang I airframe equipped with one of the earlier merlins? Performance, competiveness, perhaps even likely ranges in RAF service. Im looking for ballpark figures.



RParsifal - If you would pass a decent Hp vs Altitude and Delta weight for a 45 or a XX I could derive some in the ballpark dash speeds at those altitudes of interest.
Regards


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## Shortround6 (Apr 11, 2012)

Cola said:


> Now, this is pretty immature response, because you're ROFLMAOing at Mr.Christopher Chant and he gets payed for what he writes. You?
> He may be wrong though and I can agree that such a configuration was comparatively rare,



Mr.Christopher Chant writes books on a wide variety of military equipment including tanks and ships, and while I have a number of his books myself I don't think he is primarily a researcher. 

A Mr. Anthony Williams does disagree with him (author of "Rapid Fire", and co-author of "Flying guns of WW I" , "Flying guns of WW II" and "Flying guns the modern era") see: BOOKS BY ANTHONY G WILLIAMS

Comparatively rare is actually non-existent. 



Cola said:


> No, but neither have you for the contrary and I'm more inclined to believe official publications, than forum myths.



What official publications? 

you want me to prove a negative. 

the only way I could prove that NO 109 had such an armament would be to have photos of every 109 airframe with serial numbers. Other wise what ever serial number plane/s is not in the photo collection would be the one/s that had this fictitious armament.

Nobody to date has come up with a photo or even good engineering drawings of such an armament or even a good explanation of how would even fit. There may have been trial installations of the MK103. the MK 151s in cowl are a while other story.

You talk about a body of proof, where is the body of proof concerning this armament? 
30 websites all quoting each other or William Green's book from the late 50s do not make up a body of proof.


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## FLYBOYJ (Apr 11, 2012)

Gentlemen, please play nice....


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## Cola (Apr 12, 2012)

@drgondog,
Look buddy, don't be a child now running to papa Bell and mama Lockheed...you made calculations, made conclusions and made them both wrong, after repeatedly being advised not to do either of those.
You may even be whatever you say you are and that may matter to someone, but I don't think you understand the geometry of flight, being capable of missing the ballpark like this and that's what matters to me.
An experienced engineer, as you claim to be, should see what I'm talking about immediately, without calculating and particularly after seeing what guys that fly both types say, in the video I included a few pages back.
Now, I don't have time to check all of your calculations and logic behind it, but since you're capable of flunking basics, makes me wonder what else can you flunk...

But anyway, I'm not here to squabble, or whatever it is that you do and frankly I came here just for some data based on research.
So again, I'm sorry if I disturbed your "Mustang cult" (or whatever you run here) and thought you are smart, but now I think you're just trying to look smart...in any case so long and please stay out of my posts...thx


@ Shortround6,
thx for the input.
The data I've been referring to, are published in C.Chant's "An Illustrated Guide to WW2 Fighters", where he claims, the K-4's weapon installation has been revised by Mk103, as opposed to Mk108 found previously in K-2, which according to him, already had a pair of 15/151s in the cowling.
But yes, I suppose you are right and I'm getting more and inclined to belive that this configuration, rarely if ever saw operational use.
However, I'm still not gonna completely discount 70 years of time gap and possibility that archives are incomplete.


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## DerAdlerIstGelandet (Apr 12, 2012)

Joe told you both to play nice. Now you get a warning to play with. If you ignore a moderator when he tells you to cool it off, you can go and play some place else! It is there job to keep the peace on this forum, and they don't need children ignoring them as if this is a kindergarten. 

Also be careful if you are going to get into a "background and living in a real world" pissing contest with Bill (drgondog), as he has the "real world" academic and practical experience to back it up. If you don't Cola, I would tread carefully.


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## riacrato (Apr 12, 2012)

@Cola:
The myth about the K-4s armament is an old one and gets repeated since the 60s. Even Rall said in an interview the 109 had "15mm MGs" in the cowling.

However the truth is no primary source I know of lists the Kurfuerst with anything other than the usual MK108 and MG131s. I seem to recall there was a MK-103M (apparently shortened and lightened) being developed, but it never entered service.


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## parsifal (Apr 12, 2012)

Cola give it up for a while man. you are treading on some well respected toes in this place. You now have the attention of the mods, and even the thinking pro LW guys are backing right away from your rants. None of this is doing your position any favours or any good. My suggestion is to cool it, watch some movie or something. Let it pass man, or you will pay a heavy price


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## davparlr (Apr 12, 2012)

tomo pauk said:


> Hi, David,
> 
> The thread covers the 1941, so we should divide the airframes in service from the airframes in prototype phases. So maybe the Fw-190 should be the 1st choice here (it is in service), and along the prototype/pre-series fighters I hold the P-51 in the high regard.
> The Typhoon features rather different wings vs. Tempest, a notably different fuselage, so it should be regarded as a separate entry - the late war Hawkers are way out of this thread. Typhoon was unable to provide the RAF with a fighter of greater performance over most altitudes vs Spitfires with two-stage engines (tick wing was flatly a wrong choice), the combat range was found wanting, the tail needed reinforcement. I'd rate Spitfire as a far better airframe.


 
You are right in that the P-51 did not quite make the cut. However, I tend to disagree with your comment on the Typhoon. I think that it kind of created a family of aircraft where one led to another that had great potential. If we look at the P-51 to the P-51B to the P-51H to the F-82. I think you will find engine changes, wing changes, and fuselage changes, even configuration changes. So too with the Fw-190. Maybe not so many with the F4U, but certainly engine changes. I remember the first time I saw a Sea Fury at Chino. I was amazed at that magnificent aircraft!


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## tomo pauk (Apr 12, 2012)

Okay, I follow what you're saying. 
My assessment re. P-51: the service subtypes could be regarded as two 'branches' - one is spanning from P-51 to P-51K. The another, P-51H should be regarded as a separate branch, with maybe 10% of airframe parts being interchangeable with the latest P-51K; it was notably lighter. The fuselage was new, so was the wing empenage. Luis Watt of the NAA stated that 'P-51H is structurally no longer a P-51 - it is a brand new airplane'. 
The P-51s (excluding the -H), Fw-190s, Spitfires - all were incrementally better airplanes with new engines and small airframe modifications. Typhoon needed major airframe modification (wings, fuselage) to evolve into Tempest (engine being almost the same), hence my disagreement with your assessment of the Typhoon.


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## riacrato (Apr 12, 2012)

I for one enjoy the discussion and would wish it to continue as long as new insights are to be won. I don't have the chance yet to fully understand everything that is written here but will certainly come back later if I feel I am prepared for it.

Anyone can make a mistake if he doesn't have access to the latest research, that doesn't mean his statements are all fundamentally wrong.


Tomo brought up an interesting point that: What makes an airframe "new" as opposed to an evolution. Is the Me 109 K fundamentally the same as Me 109 B, Typhoon <> Tempest, Fw 190 <> Ta 152, P-51A <> P-51H...?Or are all of these essentially new aircraft only benefitting to a varying degree from the fundamental (wind channel and other) studies of their ancestors?


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## davparlr (Apr 12, 2012)

tomo pauk said:


> Okay, I follow what you're saying.
> My assessment re. P-51: the service subtypes could be regarded as two 'branches' - one is spanning from P-51 to P-51K. The another, P-51H should be regarded as a separate branch, with maybe 10% of airframe parts being interchangeable with the latest P-51K; it was notably lighter. The fuselage was new, so was the wing empenage. Luis Watt of the NAA stated that 'P-51H is structurally no longer a P-51 - it is a brand new airplane'.


True, but the general layout was the same, the overall design philosophy was the same, and the lineage is certainly unmistakable. The F-18E is a bigger and more powerful and has more wing area than the F-18A but there is no doubting the lineage or the F-18A design philosophy.


> The P-51s (excluding the -H), Fw-190s, Spitfires - all were incrementally better airplanes with new engines and small airframe modifications Typhoon needed major airframe modification (wings, fuselage) to evolve into Tempest (engine being almost the same), hence my disagreement with your assessment of the Typhoon.


What about the Fw-190D-9 and the Ta-152H, both which evolved from the original Fw-190. This is the adaptability that I think is important. Also, wasn't the spitfire wings modified by clipping and adapted to handle various types of guns/cannons? Wasn't the fuselage strengthened to handle bigger engines and exactly how close was the Mark 21, with new wings, to the Mark I?


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## davparlr (Apr 12, 2012)

tomo pauk said:


> Okay, I follow what you're saying.
> My assessment re. P-51: the service subtypes could be regarded as two 'branches' - one is spanning from P-51 to P-51K. The another, P-51H should be regarded as a separate branch, with maybe 10% of airframe parts being interchangeable with the latest P-51K; it was notably lighter. The fuselage was new, so was the wing empenage. Luis Watt of the NAA stated that 'P-51H is structurally no longer a P-51 - it is a brand new airplane'.


True, but the general layout was the same, the overall design philosophy was the same, and the lineage is certainly unmistakable. The F-18E is a bigger and more powerful and has more wing area than the F-18A but there is no doubting the lineage or the F-18A design philosophy.


> The P-51s (excluding the -H), Fw-190s, Spitfires - all were incrementally better airplanes with new engines and small airframe modifications Typhoon needed major airframe modification (wings, fuselage) to evolve into Tempest (engine being almost the same), hence my disagreement with your assessment of the Typhoon.


What about the Fw-190D-9 and the Ta-152H, both which evolved from the original Fw-190? This is the adaptability that I think is important. Also, the spitfire wings were modified by clipping and adapted to handle various types of guns/cannons. I also understand that fuselage was strengthened to handle bigger engines. I suspect Mark 21, with new wings, was quite a bit different to the Mark I, more that just new engine and small airframe modification.


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## tomo pauk (Apr 12, 2012)

I take it that we should draw a line somewhere, dividing the 'variant' from a 'new type'. Guess my line is more strict than yours 

BTW, Superbug is a whole new aircraft (think we were there before  ).


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## riacrato (Apr 12, 2012)

davparlr said:


> True, but the general layout was the same, the overall design philosophy was the same, and the lineage is certainly unmistakable. The F-18E is a bigger and more powerful and has more wing area than the F-18A but there is no doubting the lineage or the F-18A design philosophy.
> 
> What about the Fw-190D-9 and the Ta-152H, both which evolved from the original Fw-190. This is the adaptability that I think is important. Also, wasn't the spitfire wings modified by clipping and adapted to handle various types of guns/cannons? Wasn't the fuselage strengthened to handle bigger engines and exactly how close was the Mark 21, with new wings, to the Mark I?


IIRC Everything relevant behind the firewall (except for the plug in front of the tail and the switch from electric to hydraulic landing gear) is the same for FW 190 A and D. Ta 152 is a different animal but again, many of its prototypes were actually rebuilt FW 190 As. If I remember correctly again I read the Yak 3 shares almost no spares with the Yak 1/7/9 line eventhough they "look" very similar. Certainly the general layout and basic aerodynamic profile is the same for all of them.

This is an interesting subject. By modifying existing airframes you want to a) reduce development time and/or b) keep parts commonality high. Your example of going from a standard Spitfire to a clipped-wing Spitfire certainly is in a completely different league in both a) and b) as compared to going from a Typhoon to a Tempest.

Would be great to have that kind of info on a variety of WW2 developments, unfortunately the naming conventions give away only very little. The Bf 109 is called the most produced fighter airframe of all times, but the same title could also go to the Yak, if you count Yak 1-9 (excl. 3) as one type that evolved.


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## cimmex (Apr 12, 2012)

All Fw190A and D,G and F had electric landing gear. Only Ta 152 switched to hydraulic landing gear.
Regards 
Cimmex


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## Shortround6 (Apr 12, 2012)

davparlr said:


> True, but the general layout was the same, the overall design philosophy was the same, and the lineage is certainly unmistakable. The F-18E is a bigger and more powerful and has more wing area than the F-18A but there is no doubting the lineage or the F-18A design philosophy.
> 
> What about the Fw-190D-9 and the Ta-152H, both which evolved from the original Fw-190? This is the adaptability that I think is important. Also, the spitfire wings were modified by clipping and adapted to handle various types of guns/cannons. I also understand that fuselage was strengthened to handle bigger engines. I suspect Mark 21, with new wings, was quite a bit different to the Mark I, more that just new engine and small airframe modification.



The MK 21 Spitfire is considerably different.

The thing is trying to find the difference between lineage of "design philosophy" and actual lineage of the airframe. Could you turn a MK I Spitfire into a MK IX or vs versa without the wholesale fabrication of new parts? 

Spitfire wings changed more inboard in the area of the gun bays than at the tips. The tips on the standard wing were detachable and the "clipped" versions just had the normal tips unbolted and a filler cap bolted back in place. the extended tip nersions worked the same, a longer than normal tip was bolted on in place of the normal tip. *NO* change was made to the ailerons, the hinges or the leading edge and spar. the spar did not extend into the tip area on the normal wing. 

How much does a P-47N change from a D or even an M?


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## renrich (Apr 12, 2012)

The P51 air frame has to be it. Low drag, strong, plenty of room for fuel and armament. F4U might run a close second.


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## Siegfried (Apr 12, 2012)

A very substantial part of the Ta 152H airframe was from Fw 190 production. The aircraft was extremely manouverable, handled beautifully and could do a lazy 8 over and airfield that a 190 had no hope to match. There was no tendency to spin or stall. It could easily out turn a P-51 except for the initial turn due to roll rate. Pilots had very high confidence even against Spitfires either griffon or merlin. It was well liked. It was slower at low altitude against the P-51 or tempest but not so against the Griffon Spitfire. The potent 2800hp takeoff power DB603N with its two stage, two speed with infinitely variable drive sitting on top of 2nd gear engine also had an intercooler would have closed of even this gap. There were also 12 Jumo 213J of 2600hp on the test bench. The BMW 801R with an intercooled two stage Four speed supercharger was also slated For the Tank. This very powerful radial engine was actually physically longer than any of the in lines.


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## FLYBOYJ (Apr 13, 2012)

Siegfried said:


> The aircraft was extremely manouverable, handled beautifully and could do a *lazy 8* over and airfield that a 190 had no hope to match.



I don't know what source you extracted this from but FYI a lazy 8 is a *very basic maneuver* that in no way will show that one aircraft is more maneuvable than another. It's like taking a Lamborghini for a test drive and saying how well it handled when you parallel parked!!!

Sure you or your source didn't mean "Cuban 8?"

_"The lazy eight is a maneuver designed to develop perfect coordination of controls through a wide range of airspeeds and altitudes so that certain accuracy points are reached with planned attitude and airspeed. In its execution, the dive, climb, and turn are all combined, and the combinations are varied and applied throughout the performance range of the airplane. It is the only standard flight training maneuver during which at no time do the forces on the controls remain constant.

The maneuver is started from level flight with a gradual climbing turn in the direction of the 45° reference point. The climbing turn should be planned and controlled so that the maximum pitch-up attitude is reached at the 45° point. The rate of rolling into the bank must be such as to prevent the rate of turn from becoming too rapid. As the pitch attitude is raised, the airspeed decreases, causing the rate of turn to increase. Since the bank also is being increased, it too causes the rate of turn to increase. Unless the maneuver is begun with a slow rate of roll, the combination of increasing pitch and increasing bank will cause the rate of turn to be so rapid that the 45° reference point will be reached before the highest pitch attitude is attained.

At the 45° point, the pitch attitude should be at maximum and the angle of bank continuing to increase. Also, at the 45° point, the pitch attitude should start to decrease slowly toward the horizon and the 90° reference point. Since the airspeed is still decreasing, right-rudder pressure will have to be applied to counteract torque.

As the airplane’s nose is being lowered toward the 90° reference point, the bank should continue to increase. Due to the decreasing airspeed, a slight amount of opposite aileron pressure may be required to prevent the bank from becoming too steep. When the airplane completes 90° of the turn, the bank should be at the maximum angle (approximately 30°), the airspeed should be at its minimum (5 to 10 knots above stall speed), and the airplane pitch attitude should be passing through level flight. It is at this time that an imaginary line, extending from the pilot’s eye and parallel to the longitudinal axis of the airplane, passes through the 90° reference point.

Lazy eights normally should be performed with no more than approximately a 30° bank. Steeper banks may be used, but control touch and technique must be developed to a much higher degree than when the maneuver is performed with a shallower bank.

The pilot should not hesitate at this point but should continue to fly the airplane into a descending turn so that the airplane’s nose describes the same size loop below the horizon as it did above. As the pilot’s reference line passes through the 90° point, the bank should be decreased gradually, and the airplane’s nose allowed to continue lowering. When the airplane has turned 135°, the nose should be in its lowest pitch attitude. The airspeed will be increasing during this descending turn, so it will be necessary to gradually relax rudder and aileron pressure and to simultaneously raise the nose and roll the wings level. As this is being accomplished, the pilot should note the amount of turn remaining and adjust the rate of rollout and pitch change so that the wings become level and the original airspeed is attained in level flight just as the 180° point is reached. Upon returning to the starting altitude and the 180° point, a climbing turn should be started immediately in the opposite direction toward the selected reference points to complete the second half of the eight in the same manner as the first half."_


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## davparlr (Apr 13, 2012)

Siegfried said:


> Pilots had very high confidence even against Spitfires either griffon or merlin. It was well liked. It was slower at low altitude against the P-51 or tempest but not so against the Griffon Spitfire.


 
The data I have shows the spit XIV was very close in airspeed (quite a bit faster at SL) to the Ta from SL to 25k but with excellent climb capabiltiy.


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## Edgar Brooks (Apr 16, 2012)

Shortround6 said:


> The MK 21 Spitfire is considerably different.


The fuselage was pretty much identical to the XIV; the main difference was in the ailerons, in doing away with the Frise system. In simple terms, the centre section was widened, thereby widening the u/c tracking, and the tips were cut short; if you take a drawing of a I - XVIII wing planform, lay it over a 21-24 wing, and slide it out slightly, you'll find the shapes are almost an identical match.


> The thing is trying to find the difference between lineage of "design philosophy" and actual lineage of the airframe. Could you turn a MK I Spitfire into a MK IX or vs versa without the wholesale fabrication of new parts?


They did; N3297 was one of the initial batch of IX conversions done by Rolls-Royce. From firewall aft, the fuselage was identical, so a new nose, and a new pair of wings were all that was needed (at first.)


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## GregP (Apr 16, 2012)

The P-51K is simply a P-51D made in Dallas, Texas (all the "K's") instead of Inglewood, California (all the "D's") ... except the D model had a Hamilton-Standard propeller and the K model had an Aeroproducts propeller. Other than the prop, they were identical.


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## Siegfried (Apr 18, 2012)

davparlr said:


> The data I have shows the spit XIV was very close in airspeed (quite a bit faster at SL) to the Ta from SL to 25k but with excellent climb capabiltiy.



The Ta 152H with B4+MW50 Emergency power ie (87 octane plus ADI water injection which is roughly equal to 100/130 octane fuel) had a sea level speed of 580km/h or 360mph. This is as fast as a Mk XIV Spitifre on 21psig running 100/130 octane. The chart with this data is fairly easy to find 'einmotorige jaeger Leistungen. However the Mk XIV if running on 100/150 and 25psig boost could achieve close to 390mph. The Jumo 213E1 was meant to be upgraded to run of C3 fuel (about 96/130) which would have increased power and closed the gap. This was probably a 2050hp to 2250hp increase. Beyond that there were increments to 2350-2500 for the Jumo 213EB (enlarged valves), some 2600hp for the Jumo 213J (takeoff without WEP I believe) and 2800hp takeoff for the DB603N. The Ta 152C with its shorter span wings was designed to be more suitable for low altitude combat but I rather suspect the Ta 152H was going to show it could do a suprisingly good job of this. 

I would have to concede that the Ta 152 was slower than the Mk XIV at sea level when 100/150 fuel was available to the Spitfire. I'd like to provide scans but am rather preoccupied with work to do that right away, will do latter.


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## wuzak (Apr 18, 2012)

http://www.spitfireperformance.com/spit14speedns.jpg

359mph @ 18psi boost = 100/130 fuel.
389mph @ 25psi boost = 100/150 fuel.


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