# Top Destroyers Research — why the P-51 was king



## rousseau (Dec 12, 2010)

When we talk about fighters in WW2, the first one jump out from our brain would be P-51 Mustang, the most fierce, powerful, violent fighter for combat in air in that era we will say so.
Yes, the bubble canopy, the rectangular shaped wing makes it seemingly more handsome, neat, proportional or pulchritude even we shall say.
Nevertheless, we are not judging lady or playboy here, we ought to support self opinion by data study.
Then here is mine:





If we change it via sort in terms of unit power, we will see the P-51 down to the 15th far out of top ten.




If we exchange then in terms of Wing Load, the P-51 still sit on fifth seat




So what made Mustang so impressive? Merely nice-looking or really outstanding on specification?


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## tomo pauk (Dec 12, 2010)

#1: Quoting Japanese engine powers by the numbers found on Wiki can be missleading (eg Ki-84 was suposed to be slower than 400 mph with 2000 HP???).
#2: Re-check the power you stated for Spit Mk9 - 3000 HP is not the real-world figure.
#3: You lack drag and/or speed numbers dearly.
#4: Ditto for range.


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## evangilder (Dec 12, 2010)

You can analyze all kinds of facts and figures but the one that matters most, and what made the P-51 so successful as a fighter was it's range. You can have the best horsepower, firepower, wing loading etc. But if you can't get all those great numbers to the fight, they are meaningless.


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## tomo pauk (Dec 12, 2010)

#5: Empty weight you provided for Spit Mk.IX is wrong, perhaps some 500kg should be added.


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## rousseau (Dec 12, 2010)

Very well, the form has been corrected 








looks nothing change.
And I have no idea why the P-51 got so much long range than others? Sorry for lacking internal fuel data.


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## tomo pauk (Dec 13, 2010)

Again, no figures about drag, speed, range, then armor, armament, ammo. Your tables will not cut in, I'm afraid.
As for internal fuel carried, that requires space, which adds weight again, plus the weight of (self-sealing) tanks themselves - therefore US planes don't look nice on tables like ones you're provided.


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## rousseau (Dec 17, 2010)

According to my data which unveiled publicly, the top speed certainly is at one altitude not all height. Nothing can be prove according to such speed. If you have those aircraft's flight envelop please share.
The winf load and unit power are two most important specifications to measure how good the fighter is. When we talk about range, that Japanese aircraft are all covered P-51, do you really want to see?


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## timshatz (Dec 17, 2010)

evangilder said:


> You can analyze all kinds of facts and figures but the one that matters most, and what made the P-51 so successful as a fighter was it's range. You can have the best horsepower, firepower, wing loading etc. But if you can't get all those great numbers to the fight, they are meaningless.



Oughta add in the doctrine was a big difference. Pilots flew tours of 200 or 250 combat hours and went home. While in the combat zone, the AF flew their asses off. In that time, they were expected (at least when the P51 really started showing up which is at the begining of 1944) to hunt and destroy the Luftwaffe. It was their primary mission. 

Other nation's pilots flew shorter missions and usually flew less often. They usually didn't fly tours (especially axis and Soviet) but were up in the thick of it for the duration. They didn't have to accept combat every day, there was always tomorrow. 

The Mustang pilots flew a mass produced air superiority fighter deep into enemy territory. It was a relatively cheap aircraft to produce (when considered against the P47 and P38) with advantages neither one had (range and manuverability). They were expected to fight the enemy anywhere they found them. In a way, they swamped the Luftwaffe. But that isn't the whole story, they were expected to do that. They also ground them down as they were being ground down. After the tour is over, the US pilot goes home exhausted and another guy takes his spot to keep the pressure up. 

The Luftwaffe didn't have that luxury.


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## davparlr (Dec 17, 2010)

Trying to normalize data from different countries and sources is extremely difficult. Some data has been lost due to war and incompetence. Also, time period is a variable. For example, the power you quote for the P-51 is 1695 hp. After May, 1944, the P-51 was cleared for 1860 hp on high octane fuel. Performance at altitude is greatly affected by supercharger performance, which is often poorly defined. Factor in drag characteristics, etc, and overall, this is a tough task.

Your power rating of the P-47N is significantly off. The power of the P-47M/N is 2600 hp at SL, 2800 hp from 5k ft to 33k ft.

The exceptional Mustang range was due to excellent aerodynamics and large internal fuel capacity, 269 gallons, 1018 liters.


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## tomo pauk (Dec 17, 2010)

rousseau said:


> According to my data which unveiled publicly, the top speed certainly is at one altitude not all height. Nothing can be prove according to such speed. If you have those aircraft's flight envelop please share.
> *The winf load and unit power are two most important specifications to measure how good the fighter is.* When we talk about range, that Japanese aircraft are all covered P-51, do you really want to see?



Is the part I've bolded a proven fact of just opinion?

As for Japanes planes, please do post the figures.

As for speed, P-51(B/C/D) was the king from 15-25 kft, so that covers it.

Another thing, could you pick any of the planes from your tables and assign it for a task P-51 was tasked? Provided it has all: range, performance edge vs. opponents, worthwhile armament, ammo, durability...


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## davebender (Dec 18, 2010)

A6M2. Entered service during 1941.
P-51D. Entered service during mid 1944.
.....Should be comparing the A6M5, Ki-61, Ki-84 etc.

The P-51D was designed for high altitude operations. At 25,000 feet I suspect it would eat a Tempest for lunch. Conversely, at 5,000 feet the P-51D would probably be in trouble vs a Tempest.

Since the P-51D entered service during mid 1944 it should be compared to late model Me-109Gs equipped with newer engines like the 1,800hp DB605AM.

This is not intended as criticism. The P-51D was a good fighter aircraft and relatively low cost to produce (especially compared to most other U.S. fighter aircraft). Firepower was relatively weak. Otherwise it compared well overall with most contemporary fighter aircraft produced during the final year of WWII.


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## comiso90 (Dec 18, 2010)

Also...

I wouldn't use the term "Destroyer" when referencing the P-51. Destroyers is a term used for aircraft to take down Heavy bombers at altitude.. IMO, the Allies really didnt have a Destroyer because they didnt need one!


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## johnbr (Dec 18, 2010)

Me I still love the K84.


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## davebender (Dec 18, 2010)

Britain did. They had the heavily armed Beaufighter and eventually the Mosquito. If Germany had launched raids consisting of 1,000 He-177s and/or Fw191Cs RAF destroyers would have been used similiar to the Luftwaffe Me-110 and Me-410. They would have been supplemented (and escorted) by cannon armed Spitfires.

I suspect it takes quite a few .50cal bullets to hack down an aircraft the size of a He-177. The U.S. Army Air Corps would have been in trouble without a decent fighter cannon.


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## comiso90 (Dec 19, 2010)

The Boulton Paul Defiant was one of the first attempts by the allies to be a Destroyer

Boulton Paul Defiant - Wikipedia, the free encyclopedia

Forward thinking... unrealized.

.


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## rousseau (Dec 19, 2010)

comiso90 said:


> Also...
> 
> I wouldn't use the term "Destroyer" when referencing the P-51. Destroyers is a term used for aircraft to take down Heavy bombers at altitude.. IMO, the Allies really didnt have a Destroyer because they didnt need one!



In your sound the word destroyer should be used to describe interceptor?
This is also a good question to define destroyer.


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## comiso90 (Dec 20, 2010)

rousseau said:


> In your sound the word destroyer should be used to describe interceptor?
> This is also a good question to define destroyer.



Hello Rousseau,

Certainly the definition is fuzzy but by my definition, a destroyer puts more emphasis on armament while the interceptor prizes rate of climb more. The Me 262 was both but one version imparticular was certainly a destroyer:






The English used the Spitfire and Hurricane as interceptors but neither one was armed robustly enough to be considered a Destroyer.

The P-51 was an excellent long range bomber escort and, on occasion, would be used as an interceptor but I cant imagine labeling it a "destroyer".

We can post photos all day but these are the weapons of a destroyer:


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## Glider (Dec 20, 2010)

comiso90 said:


> Also...
> 
> I wouldn't use the term "Destroyer" when referencing the P-51. Destroyers is a term used for aircraft to take down Heavy bombers at altitude.. IMO, the Allies really didnt have a Destroyer because they didnt need one!



The allies didn't have what you call a destroyer, for the simple fact as you rightly say, that they didn't need one.
If they had such a requirement there would have been alternatives, the one that springs to mind is the Mossie with the 6pd gun. They did shoot down one bomber with it, which was if I recall correctly a Ju88, also the Martin Baker III would have been an option with 6 x 20mm.

That said the RAF with Spits armed with 4 x 20mm had something that the Luftwaffe didn't have, a heavily armed high altitude fighter. An armament of 4 x 20mm would suffice in most situations so I would doubt the need for more.


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## davebender (Dec 27, 2010)

> RAF with Spits armed with 4 x 20mm had something that the Luftwaffe didn't have, a heavily armed high altitude fighter



*Me-109G6/R4*
WW2 Warbirds: the Messerschmitt Bf 109 - Frans Bonn
GM1 for improved high altitude performance.
1 x 30mm Mk108 cannon. Firing through prop hub.
2 x 30mm Mk108 cannon. One in each wing.

There's nothing wrong with the Spitfire. But the bomber-killer version of the Me-109G6 had even more high altitude firepower.


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## Glider (Dec 27, 2010)

As a bomber killer I would agree with you but, and its a big but, the G6/R4 was wide open against fighters. Its handling was very poor whereas the Spit with 4 x 20mm retained its good handling.
The GM1 I admit to having mixed feelings about, while it worked it was fine but it only worked while the fuel lasted. Before it was used it added more weight to what was already a heavily loaded aircraft. 

The Lufwaffe seemed to have a choice, the Fw 190 which was fine against bombers but wasn't that good at altitude against fighters. Or the 109 which was better at altitude against fighters, but lacked the firepower against bombers. Add the firepower and the performance at altitude dropped which is why the P51 as an escort was so vital. 
Almost all Spits could be armed with 4 x 20mm due to the flexible design of the wing and could also be quickly fitted with extended wingtips giving you a well armed fighter with good handling at altitude.


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## davebender (Dec 27, 2010)

*Me-109G6.*
Kurfrst - Flugleistungen Me 109G - Baureihen
3,350kg. Loaded weight. Armed with 2 x MG131 plus 1 x MG151.
215kg. Additional weight for 1 x MG151/20 under each wing.
I could not find a Luftwaffe data sheet for an aircraft armed with 3 x 30mm Mk108 cannon. However the weight difference would be small.
30mm Mk108 cannon weight = 58kg.
20mm MG151/20 cannon weight = 42 kg.
So.....
Loaded weight with 3 x 30mm Mk108 cannon should be about 3,600kg.

*Spitfire Mk IX.*
Spitfire Mk IX Performance Trials
7.450 lbs. Loaded Weight.

*P51D.*
North American P-51 Mustang - Wikipedia, the free encyclopedia
9,200 lbs. Loaded Weight.

The Me-109 and Spitfire weigh approximately the same. Both have an excellent power to weight ratio compared to contemporary fighter aircraft like the P-51D.


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## Glider (Dec 27, 2010)

The problem wasn't just this weighs X and this weighs Y. From the basic design the RAF replaced 4 x LMG with 2 x 20mm. Germany added 2 x 30mm and replaced a 20mm with a 30mm as well as adding the additional drag from the underwing mounting

The problem was the impact on handling. The Me109 was badly impacted and all parties recognised that it transformed its agility. The additional weapons on the Spit impacted its climb but its general agilty was untouched. The official comparison of the Spit Vc with 4 x 20mm and the Normal Spit Vb concluded
_There is no noticable difference between the handling characteristics of this aeroplane and other Spitfire V types_.Spitfire Mk V Performance Testing
This is the key difference, the Spit could handle the weight better than the 109.


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## davebender (Dec 27, 2010)

The Me-109G with wing mounted cannon max speed was 8kph slower (per the Luftwaffe data sheet). I wouldn't call that "badly impacted".


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## Shortround6 (Dec 27, 2010)

There is also climb, turn rate or turning circle, rate of roll, rate of roll acceleration (aileron response) stability in 3 axis, and not the least, landing speed or landing characteristics. 
Maybe a few I left out.
The under wing guns may not have affected some of these but there is a lot more to handling characteristics and impacting flying quality than just top speed changes.


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## Glider (Dec 28, 2010)

davebender said:


> The Me-109G with wing mounted cannon max speed was 8kph slower (per the Luftwaffe data sheet). I wouldn't call that "badly impacted".



The following is from Kurfurst site

Me 109 G-6/R6:
"- What about the Cannon Messerschmitt? 
Kössi (Karhila) said, "I can fly her, I take her." But I said, very well, I don't want... She was such an unwieldy one. I got in a dogfight flying one against (P-38) Lightnings and was unable even to climb up to them. They were a little higher, and I tried to climb to get at them but ran out of speed... I don't know how Kössi managed to fly her. He must have his own tricks or he had a different starting point. I had to fly one in battle only two or three times.

My understanding is that the Me 109's with the extra cannon needed an escort themselves due to the drop in agility. They were vulnerable to escorting fighters.


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## davebender (Dec 28, 2010)

> a lot more to handling characteristics and impacting flying quality than just top speed changes


I agree.

However the amount of speed decrease provides an indication as to how much overall flight performance was impacted.


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## drgondog (Dec 28, 2010)

The three key factors that set the Mustang B/C/D/K apart were:

The best aerodynamics of any piston engine fighter. Lowest drag, coupled with additional thrust due to Meridith Effect of radiator cooling design. Only the jets had a comparable CDo. This was a 'hidden advantage' because the 51 retained energy better than comparable high Hp, comparable (and lower) wing loading adversaries because it bled less energy due to drag in manuevers.

Great internal fuel capacity with 192 gallons in the wing, 85 (operationally reduced later to 65) gallons in the fuselage tank, and capability of attching two 110 gallon tanks for combat operations.

A near perfect match of an engine to the 'Primary Mission' - namely the Merlin with two stage supercharger for optimal performance at ~ 15,000 and 25,000 feet depending on the dash number.

Combine that with pretty good wing loading, pretty good firepower, and pretty good manueverability - it was able to achieve near parity in turn, roll, and climb (better than some adversaries, slightly worse than others), very good dive and significant advantage in speed - over Berlin. Over Tokyo it had a disadvantage in climb and turn but still great performance at B-29 altitudes for daylight missions.


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## drgondog (Dec 28, 2010)

davebender said:


> The Me-109G with wing mounted cannon max speed was 8kph slower (per the Luftwaffe data sheet). I wouldn't call that "badly impacted".



Consider that the impact wasn't so much to speed but to turn and climb due to the extra weight and increased drag and rolling moment inertia... 

so moving from near parity or superior characteristic (turn, speed, climb, acceleration, roll) to less than parity or neutral for that which was once an advantage is very important versus all the 109G contemporary adversaries.


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## davebender (Dec 29, 2010)

How much of an impact?

Me-109s were known for having an excellent rate of climb compared to contemporary fighter aircraft. You could lower the climb by a few hundred feet per minute and still be superior to most of the competition.


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## drgondog (Dec 29, 2010)

davebender said:


> How much of an impact?
> 
> Me-109s were known for having an excellent rate of climb compared to contemporary fighter aircraft. You could lower the climb by a few hundred feet per minute and still be superior to most of the competition.



Enough of an impact that the LW quit putting Gondolas on Me 109G6 after introduction of Mustangs proved that the diminished performance in speed, climb and acceleration was life (and mission) threatening. 

As you know the underwing armament was installed to make the 109 a better B-17/B-24 destroyer - all good absent fighter escort, but bad idea against a fighter that was already 30-50mph faster at 25K and had near equal performance in turn and climb.

That airplane found it difficult to evade, once engaged.


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## davebender (Dec 30, 2010)

> LW quit putting Gondolas on Me 109G6 after introduction of Mustangs


If P-51s are the issue then we are talking about only the final year of the war. By then I believe the bomber-destroyer role had mostly been assumed by specialized versions of the Fw-190. Which makes sense since the Fw-190 had a greater payload then the lightweight Me-109. The Fw-190A8 could carry serious firepower plus decent armor to protect the pilot from .50cal MG fire. Such a heavily loaded aircraft isn't competitive vs enemy fighters except in a dive. That's the price you pay for survival from massed B-17 machinegun fire. It also dictates your tactics. Dive through the bomber formation and keep going, letting Me-109s tangle with the escort fighters.

Fw-190A8/R1. 6 x MG151/20 cannon plus 2 x MG.
Fw-190A8/R2. 2 x MG151/20. 2 x 30mm Mk108. plus 2 x MG.
Fw-190A8/R3. same as R2 variant except 30mm cannon mounted differently.
Fw-190A8/R6. Two underwing launchers for 21cm rockets.


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## cocky pilot (Dec 30, 2010)

rousseau said:


> When we talk about fighters in WW2, the first one jump out from our brain would be P-51 Mustang, the most fierce, powerful, violent fighter for combat in air in that era we will say so.
> Yes, the bubble canopy, the rectangular shaped wing makes it seemingly more handsome, neat, proportional or pulchritude even we shall say.
> Nevertheless, we are not judging lady or playboy here, we ought to support self opinion by data study.
> Then here is mine:
> ...




As in sport you can only judge a plane by its peers, the hurricane in 1940 turned back more bomber raids than any other plane IMHO...but that isnt a claim of superity, rightly or wrongly some planes just have a brief time in the sun. The LW had to stop daylight attacks on the UK due to losses, most losses especially for bombers were due to hurricanes QED hurricane was the best destroyer (the spitfire and Chain home played a part too but that isnt the question)


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## davebender (Dec 31, 2010)

That pretty well sums up my opinion of the P-51. For a little over a year it was an effective bomber escort. By the spring of 1945 it was approaching obsolescence due to the introduction of jet fighter aircraft.


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## Shortround6 (Dec 31, 2010)

davebender said:


> That pretty well sums up my opinion of the P-51. For a little over a year it was an effective bomber escort. By the spring of 1945 it was approaching obsolescence due to the introduction of jet fighter aircraft.


Well that rather sums up ANY late war piston engined aircraft no matter what nation doesn't it?


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## davebender (Dec 31, 2010)

I agree. 

Consequently I wouldn't call late war piston engine aircraft like the P-51 and Fw190D9 "king". Most of WWII was fought without them and they were outdated as soon as the war ended.


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## drgondog (Dec 31, 2010)

davebender said:


> If P-51s are the issue then we are talking about only the final year of the war. By then I believe the bomber-destroyer role had mostly been assumed by specialized versions of the Fw-190. Which makes sense since the Fw-190 had a greater payload then the lightweight Me-109. The Fw-190A8 could carry serious firepower plus decent armor to protect the pilot from .50cal MG fire. Such a heavily loaded aircraft isn't competitive vs enemy fighters except in a dive. That's the price you pay for survival from massed B-17 machinegun fire. It also dictates your tactics. Dive through the bomber formation and keep going, letting Me-109s tangle with the escort fighters.
> 
> Fw-190A8/R1. 6 x MG151/20 cannon plus 2 x MG.
> Fw-190A8/R2. 2 x MG151/20. 2 x 30mm Mk108. plus 2 x MG.
> ...



The point was about the performance reduction (which you perceived as slight with the addition of the underwing gondolas) and why that was important - was it not?

Point - the Mustang I entered combat ops in April 1942 and remained through the end of the war in Europe. The Mustang III/P-51B/C entered combat ops in December 1943. The war ended in September 1945.

The war for P-51 vs LW ended in May 1945. The P-51B/C/D was a crucial factor for 17 months as a high altitude escort and air supremacy fighter - for that specific role it was the best in WWII. Even in the PTO, where great numbers of excellent P-38s were available - it was the Mustang that deployed to Tinian and Iwo Jima, to provide daylight escort and starfing roles. 

Point -In that specific role, it 'rendered' obsolete all bomber destroyers (save the Me 262 and arguably the Me 163) which did not have fighter escort. The Me 410, the Me 109G6/R4, the Me 110, the Ju 88, etc all disappeared during daylight war over Germany in the late July, 1944 timeframe. Even the Fw 190A-8 needed 109s for high cover (sans gondolas).

Point - the Me 109G w/underwing gondolas was driven from the sky in the April-May timeframe because 'it' could not effectively compete with the P-51B/C. Note - I said 'effectively' to emphasize that the performance reduction stripped away the Me 109s positive advantages (climb), worsened its neutral attributes (acceleration and roll) and diminished its already 'other' disadvantage (dash speed).


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## kc5sjq (Sep 22, 2011)

This was taken from Chuck Hawks web site which takes a look of fighters during WWII. I think from where we stand today and look back we could loose the importance perspective of the P-51 from the men that fought in campaign's across the world while we only see this plane still being flown today just for sport. I only offer this article as information but suggest to read all about the selection of aircraft the time the P-51 was flown and then you can make your own conclusion from his web site. I only respectfully suggest you might not realize of how this aircraft could have turn the war and other campaign's. This can bring about in essence of the statement of it being "King" while seeing it flight for sport today.

For the complete article please go to: <http://www.chuckhawks.com/best_fighter_planes.htm>
***************************************************************************************************
The Best Fighter Planes of World War II 
The Bf 109, Spitfire, FW 190, P-51, Yak-3, A6M Zero, P-38, F4U and Ki-84 
By Chuck Hawks

Due to the rapid advance of technology, the best fighter early in the war was never the best fighter late in the war.

European Theater, Early Period
In the European Theater of Operations, early years, there were two absolute standout fighter planes. Both were severely limited in range, but in a dogfight they reigned supreme in the ETO. Of course, I am talking about the British Supermarine Spitfire and the German Messerschmitt Bf 109.
The former was designed by R. J. Mitchell and the latter by Willie Messerschmitt. They were the standout air superiority fighters of the early years of the war in Europe and the leading members of the cast that fought the most famous air battle of them all, the Battle of Britain (not to slight the Hawker Hurricane, designed by Sidney Camm, which actually out numbered the Spitfire on the British side of the famous battle and scored more victories over German airplanes.


European Theater, Later Period
After the first couple of years, in the European theater, things become more complicated. During the 1939, 1940, and 1941, the Spitfire and Messerschmitt Bf 109 were clearly the dominant fighters. However, as the war wore on, many new designs entered combat.
In 1942 (really beginning late in 1941) the Focke-Wulf 190 appeared in numbers and immediately established a measure of superiority over the Spitfire Mk. V, already hard pressed by the Bf 109F. In 1942, the first year of the war for the U.S., American P-39 and P-40 fighters were generally out performed by the German Messerschmitt and Focke-Wulf fighters and things looked a bit bleak for the Allies. However, when the Spitfire Mk. IX and the P-38 started to make their presence felt, things began to improve for the Allies.
In the Spring of 1943, the P-47B went into operation in England. The Focke-Wulf 190, up until now the premier fighter in the theater, was suddenly hard pressed by the big American fighter, particularly at high altitude. In mid-1943 the much improved P-38J started to arrive and the pressure on the Germans increased. The arrival at the end of 1943 of the P-51B, the long range escort fighter the Americans so desperately needed, marked the beginning of the end for the Luftwaffe. Able to escort the bombers all the way to Berlin and back, the Mustang left the Luftwaffe no place to regroup and train. The P-51 did to the Luftwaffe what the Bf 109 did not have the range to do to the RAF earlier in the war.
So while all of the above fighters played an important part in the war, it was the P-51 that turned out to be decisive. The Americans could have won their daylight air war over Germany with the improved P-38J and L or P-47D, both of which appeared in 1944, but in fact it was the P-51, more than any other single fighter, that did it. So it seems only fair to examine first the FW 190 and then the P-51 Mustang, as the two successive "bests" of the later part of the European war.

North American P-51 Mustang
Many top E.T.O. aces flew the P-51 Mustang. These included Captain Don Gentile (35 victories), Captain John Godfrey (31 victories), Colonel Eagleston (23 victories), Major James Howard (the only American ace in both theaters of the war--6 victories in China flying P-40's and 6 victories in Europe flying P-51's), Chuck Yeager (who later became the first man to break the sound barrier) and Colonel Donald Blakeslee (15 victories and C.O. of the famous 4th Fighter Group). The 4th FG destroyed over 1,000 German aircraft, more than any other American fighter group in WW II.
The Mustang story began in 1940 when the British contacted North American Aviation with a request to build fighters for the RAF. North American was willing, and they offered to design and build a new fighter that would meet British requirements, and be easy to mass produce. In only 100 days NAA rolled out the first prototype Mustang. By November 1941 the first of over 600 aircraft produced under British contract were delivered to the RAF.
The new fighter incorporated some advanced ideas, in particular a laminar flow wing of thin cross section, which allowed the Mustang to avoid most of the "compressibility" dive problems that plagued many other high performance fighters of the time. Two of the first ten Mustangs built were taken to Wright Field, at Dayton Ohio, for testing by the AAF, which designated them XP-51.
The 1,150 hp. Allison F-series V-12 powered the early Mustang models. This resulted in poor high altitude performance, so the RAF used their Mustang I (P-51) and II (P-51A) models for low altitude ground attack and reconnaissance duties.
The Mustang I had a top speed of 370 m.p.h. at 15,000 ft. Best climb at 11,300 ft. was 1,980 ft./min. An assortment of .30 and .50 caliber machine guns were carried, but the Mustang IA was armed with 4-20mm cannon. Handling and maneuverability were good. Like the FW 190, the P-51 was a pilot's airplane.
P-51A (Mustang II) production was divided between America and Britain. This model standardized armament as 4-.50 cal MG. (two per wing). There were ground attack versions of the P 51A in U.S. service, designated A-36A, which served the AAF in the North African campaign. There were also specialized photo reconnaissance versions of all major Mustang models, the F-6 series.
The decision was made to mass produce the outstanding Merlin engine under license in the United States. The P-51B and C models (Mustang III's in Britian), which entered service in December of 1943, were powered by the new Packard-built version of the Merlin V-12, driving a four bladed propeller. At the same time, the airframe was strengthened, the radiator was re-designed, the ailerons were improved, and racks for long range drop tanks or bombs were added under the wings.
The 1,450 hp. Packard/Merlin engine (1,595 hp. war emergency rating) gave the P-51B-7 a top speed of 445 m.p.h. Best climb was 3,320 ft./min. at 10,000 ft. The new Mustang carried 4-.50 caliber MG (two per wing), and up to 1,000 lbs. of external stores. Its range was an astounding 2,200 miles with two 150 gal. drop tanks. Endurance with drop tanks was 8.7 hours.
The new engine completely changed the character of the Mustang, turning it into a high altitude fighter suitable for bomber escort missions. It came at a crucial moment for the AAF daylight bombing campaign. Luftwaffe fighters were taking such a toll of un-escorted heavy bombers that the losses were becoming unsupportable. The great range of the P-51B-7 allowed it to escort the heavy bombers all the way to their targets deep inside Germany. In March of 1944, Mustangs went to Berlin. Eighth Air Force bomber losses plummeted, while Luftwaffe fighter losses skyrocketed.
Later in 1944 the famous P-51D model arrived. It sported a "tear drop" canopy for better all around vision and a more powerful 1,790 hp. version of the Packard/Merlin engine, along with many detail improvements. The armament was increased to 6-.50 caliber wing MG and all manner of external stores could be carried. Recognition of the D model is easy because of its teardrop canopy and the large fillet fin added in front of the vertical stabilizer. For the Luftwaffe, the end was at hand.
The final major production version of the Mustang was the P-51H. This re-designed model incorporated major improvements, as extensive in scope as those incorporated into the FW 190D or Spitfire Mk. 22.
In the H model, the structure was increased in strength by 10%, to allow higher "g" loads in combat maneuvers. No structural part was left in common with earlier models. Streamlining was improved to increase speed and stability was increased. A new version of the Packard/Merlin, incorporating water injection, delivered over 2000 hp. These changes resulted in the finest American fighter of the war. Speed was 486 m.p.h. at 30,000 ft. best climb rate was 5,350 ft./min. at 5,000 ft. Service ceiling was 41,600 ft.
Unlike most other American piston engine fighters, which were withdrawn from service soon after the end of WW II, the Mustang fought on, doing valuable ground support work in the Korean War. It was adopted by many other nations, too numerous to list here, and remained in service in some countries into the 1960's.


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## Ivan1GFP (Nov 10, 2011)

The Me109G-6/R-6 cannon boat could outmaneuver the Mustang (unknown variant) per British tests.

- Ivan.


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## Glider (Nov 11, 2011)

Ivan1GFP said:


> The Me109G-6/R-6 cannon boat could outmaneuver the Mustang (unknown variant) per British tests.
> 
> - Ivan.



Do you have any more info on this. I have seen most of the combat test reports and don't remember anything like this


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## Denniss (Nov 17, 2011)

It's a Bf 109 G-6 with R6, not a G-6/R6 BTW


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## SHOOTER (Apr 13, 2012)

tomo pauk said:


> Is the part I've bolded a proven fact of just opinion?
> 
> As for Japanes planes, please do post the figures.
> 
> ...



Your entire premise is wrong!

Maximum performance is almost entirely irrelevant! It is typical performance that mattered most!

The P-51 was great because it was fast at cruising speeds. That in turn meant that it took longer for the bad guys to sneak up behind you and that in turn meant that you were more likely to see them coming and thus avoid dyeing! Depending on who you like, they all give about the same data; That is 90-93% of all kills are Vs pilots who never knew they were under attack until it was much to late to do anything about it!

That makes the SINGLE most important factor in determining the relative merits of combat aircraft in the prop age, cruising speed!

Other considerations are plane size and thus visibility, or range at which it may be seen.

Range, Fuel Fraction, or persistence. More equals more chances to find and kill the bad guys. It also means more time at larger throttle openings. Larger throttle openings give the user more options and performance. If the target is far from home and can not use full throttle while still returning to home, then his target plane is greatly restricted in it's performance.

Weapons fit and performance. Weapons with higher rates of fire, MV and BC are more effective than those with less of those things.


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## FLYBOYJ (Apr 13, 2012)

SHOOTER said:


> That makes the SINGLE most important factor in determining the relative merits of combat aircraft in the prop age, cruising speed!


And how is that when cruising speed is based on mission profile, load out and altitude?!?!?


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## tomo pauk (Apr 13, 2012)

SHOOTER said:


> Your entire premise is wrong!
> 
> Maximum performance is almost entirely irrelevant! It is typical performance that mattered most!




What would be my 'entire premise'? Why do you think that maximum performance is 'almost entirely irrelevant'. What is a 'typical performance'?



> The P-51 was great because it was fast at cruising speeds. That in turn meant that it took longer for the bad guys to sneak up behind you and that in turn meant that you were more likely to see them coming and thus avoid dyeing! Depending on who you like, they all give about the same data; That is 90-93% of all kills are Vs pilots who never knew they were under attack until it was much to late to do anything about it!



Maybe a plane with good max performance is bound to also cruise rather fast? What source gives the 90-93% figures for the kills that were achieved against the enemy that was not aware of the attack?



> That makes the SINGLE most important factor in determining the relative merits of combat aircraft in the prop age, cruising speed!



According to whom? Is the following part of your post the answer to mine, or not?



> Other considerations are plane size and thus visibility, or range at which it may be seen.



Size does not equates visibility; the pilot in Bf-109 was more hampered with visibility than Tempest's driver, despite flying a smaller airplane.



> Range, Fuel Fraction, or persistence. More equals more chances to find and kill the bad guys. It also means more time at larger throttle openings. Larger throttle openings give the user more options and performance. If the target is far from home and can not use full throttle while still returning to home, then his target plane is greatly restricted in it's performance.



Interesting. I've myself gave the nod for P-51 for the combat range.



> Weapons fit and performance. Weapons with higher rates of fire, MV and BC are more effective than those with less of those things.



Okay...


There is really no need to shout (=red letters, explanation marks for consecutive sentences)


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## davparlr (Apr 2, 2013)

The P-51 was not king. There were many capable aircraft on all sides during the war, many out-performing the P-51 in some aspects of their performance envelop. The P-51 just appeared at the right time with the right performance that allowed it to make a significant impact to the war. When I first joined this site seven years ago I did not know much about the P-51 even though I had been an AF pilot. My favorite aircraft was the F4U and Navy aircraft in general. I had Naval aircraft models hanging all over my room (my favorite aircraft is still the F8U). However, it appeared to me that at that time, there was quite a lot of P-51 bashing going on, some justifiable due to its overly glowing popularity. I decided to put on the mantle of nationalistic pride and become a defender of the Mustang, and started studying this aircraft. The more I studied, the more I was impressed with this quite capable aircraft. 

There are significant myths still accepted by many, including members of this site. One of these myths is that the Mustang was an average fighter that was successful because of its range and its numbers. Another is that it while it was a capable medium-to-high altitude fighter; it lacked capability at low altitude. Third, the P-51 only was effective because it always had significant advantages in numbers compared to the opposing enemy defenders. Let me address the first two issues as the third has often been proven wrong in several places on this forum.

First, the P-51 was fast. With its clean aerodynamics, already discussed by Drgondog, it was faster than the great majority of contemporary enemy aircraft from SL to ceiling, mostly, significantly faster. With a SL speed of over 380 mph (386 mph for the B), there were no aircraft, except for the Tempest II, significantly faster until the final generation of propeller aircraft. At high altitude where it was in its element, only the much too-late and too few, hot-rod, short-ranged Bf-109K-4, was faster.

Second, it could climb with the best of them. After May, 1944, the P-51B had a SL climb rate of over 4400 ft/min., clean and at fighter weight. Again only the Bf-109K-4 was significantly better at climb rates in general.

The late 1944, Fw-190D-9, an excellent propeller fighter considered by many as the best German propeller fighter of the war, and the considered by many to be the best WW2 propeller fighter, could only fly nose-to-nose in speed and climb with the mid 1944, P-51B up to 15-20k ft. Above that, the P-51 quickly outperformed it in speed and climb. The P-51D was only slightly behind the two below 20k, outperformed the Fw-190D-9 above 20k. The Fw-190D-9 did have better firepower than either P-51s, but the P-51s certainly demonstrated effective firepower against fighter aircraft. In addition, the P-51 empty weight was 7,125 lbs with a max TO weight of 11,600 lbs for a total loaded weight capacity of 4475 lbs. The Fw 190D-9 had an empty weight of 7,694 lbs and a max TO weight of 10,670 lbs or a total loaded weight capacity of 2,976 lbs., 1500 lbs less than the P-51, which makes the P-51 far more flexible in application. 

As was mentioned in another entry, the P-51 has the cleanest airframe for any WW2 propeller fighter. Now let’s look at the effects of aerodynamic efficiencies on climb and acceleration. Climb and Acceleration is a function of excess power, not absolute power. Comparing the post May ’44, P-51D with the Bf 109G-14 (ASM), a powerful machine. These aircraft are roughly equal in power At 20k ft but the P-51 is approximately 40% heavier in empty weight. At this altitude, the max speed of the Bf 109 is 403 mph. The max speed of the P-51 is 431 mph. If these two aircraft were flying side-by-side at that airspeed, the Bf 109 would be balls-the-wall using all its available power to maintain airspeed. The P-51 on the other hand, would be throttled back to about 80% (if my estimate is accurate). So, at these conditions, the P-51 can out-accelerate the Bf 109 because the Bf 109 cannot go faster without descending whereas the P-51 can easily do so. Similarly, the P-51 can out-climb the Bf 109 because the Bf 109 has no excess power to climb at that airspeed whereas the P-51 has excess power to do so. As airspeed goes down, this ratio does change but the concept remains in effect. The point is that simple wing loading and power loading values are only part of the equations for climb and airspeed and helps explain why the relatively heavy P-51 is such a good performer.

The P-51 was not the king, but it was an exceptionally good fighter and made a major impact on the war. It was a fighter that could fly 600 miles, fight viciously at all altitudes, and was competitive to enemy aircraft over the enemy homeland, and then fly back. While noted as an excellent escort fighter, it is often overlooked in its devastating ability as a deep interdiction fighter and is often disrespected for its very good dog-fighting capability at all altitudes. It was an unusual plane in that while it had exceptional capability in speed and range, it had very few weaknesses.


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