# Favorites and their achilles heels!



## Arossihman (Jan 29, 2012)

Since we always discuss our favorite warbirds strongpoint why dont we flip it over and discuss what we think or know our favorite warbirds weak points are. Lets start with the fighters and you guys can go whatever direction you wish from there! I'll start with mine,the P-47. I believe its weak points were,range,weight,and,climb rate in the early models.
Tony8)


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## davebender (Jan 29, 2012)

Production cost. 

The P-47 was horribly expensive for a WWII era fighter aircraft. So was the P-38. I doubt anyone except the USA would have considered producing such expensive aircraft.


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## Arossihman (Jan 29, 2012)

Well played sir!


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## Thorlifter (Jan 29, 2012)

My favorite is the Corsair. Unfortunately for the purpose of this discussion, the Corsair had no weaknesses! Ha. I guess I would have to say range. It also could do a 4 G inverted negative dive! hahaha.


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## michaelmaltby (Jan 29, 2012)

*P-39 *

I'll speak up for my favorite beauty - Bell's P-39 Airacobra. The Russians loved this plane matched as top cover for Il Sturmaviks. It was the 'right' platform for the Eastern Front air war. But to be useful for the Americans and the British the P-39 needed better endurance and higher performance. Those issues were never addressible in the P-39's unique air frame. 

MM


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## parsifal (Jan 29, 2012)

Spitfire: Its limited range and limited fighter bomber capabilities. Feels like I am blaspheming when I do this


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## GrauGeist (Jan 29, 2012)

The Corsair was nicknamed the "Ensign Eliminator" for a reason...that's enough of a "weakness" in my book! lmao


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## Catch22 (Jan 29, 2012)

I wouldn't say the Corsair's range was an issue. They removed the wing tanks in the -1D and later because they didn't need the range. That said, GG has it right. It was tricky on the ground, but from what I've read it's not any more difficult than a Mustang. I think it got a bad rep from the early issues that were repaired with the oleos and it stuck.


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## davebender (Jan 29, 2012)

Not the aircraft per se but the U.S. Army Air Corps didn't have enough sense to adopt the F4U. Apparently it had enemies in high places (and I don't mean Japanese aircraft).


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## Shortround6 (Jan 29, 2012)

Arossihman said:


> Since we always discuss our favorite warbirds strongpoint why dont we flip it over and discuss what we think or know our favorite warbirds weak points are. Lets start with the fighters and you guys can go whatever direction you wish from there! I'll start with mine,the P-47. I believe its weak points were,range,weight,and,climb rate in the early models.
> Tony8)



Do you mean weak points in regarding the original specification or intent of the aircraft or weak point/s as used once in large scale production 3-6 years after design work and being assigned missions they were never originally intended for?


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## GrauGeist (Jan 29, 2012)

Right, Catch...they installed a stall slat to keep the left wing from dipping at close-to-stall speeds.

The horrible forward vis on approach made it dangerous to land coupled with the tendancy to literally spin the aircraft on it's back at low speeds if you throttled up to fast.


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## renrich (Jan 29, 2012)

The Corsair was a challenging aircraft to land particularly on a flight deck but other than that it had a design flaw which made it slightly less suvivable, especially to ground fire. The two oil coolers in the leading edge of the wing roots were not protected until the AU. Of course those oil coolers were not as vulnerable as the cooling system of a liquid cooled engined fighter.


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## Catch22 (Jan 29, 2012)

GrauGeist said:


> Right, Catch...they installed a stall slat to keep the left wing from dipping at close-to-stall speeds.
> 
> The horrible forward vis on approach made it dangerous to land coupled with the tendancy to literally spin the aircraft on it's back at low speeds if you throttled up to fast.



It's amazing how such a small addition can make that big of a difference!

The Fleet Air Arm came into the deck in a turn in order to be able to see better. I find it hard to make too many comments about landing and ground handling as I'm not a pilot, and of course haven't flown a Corsair, but it definitely had its vices, which thankfully(?) were all seemingly on the ground. All I know is most pilots did end up loving the aircraft, and some of the early Navy squadrons that were equipped with it missed it badly when they were forced back into Hellcats. Then again, you have Bill Atkinson, a Canadian pilot in the FAA who flew Hellcats and didn't like the Corsair as he found it too complicated.

That brings up an interesting point, I'm not aware of any major vices with the Hellcat.

EDIT: Ah yes, forgot about that renrich. Those were more of an issue in Korea, were they not? (As a side note I bought "Corsair" by Tillman that you suggested, not finished yet but so far it's very good)


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## renrich (Jan 29, 2012)

The major vice of the Hellcat was that when it first was deployed many felt the performance margin over the Zeke was not great enough. That was alleviated somewhat by the F6F5 but by that time the Corsair was beginning to replace all Hellcats. Linnekin, in "80 Knots to Mach Two" said that the Hellcat had atrocious right rudder forces and not nearly enough right rudder trim to compensate. All of it's control forces were substantial. It sounds as if the Hellcat was designed to be flown by a low time pilot who was not going to try a lot of fancy maneuvers and wanted a safe airplane. Which was what it was.

A minor point but the spoiler on the right wing of the Corsair was to make the right wing stall at the same time the left wing stalled. That left wing stalling first was apparently the case in a number of piston engined fighters. Eric Brown described the FW190 as having the same characteristic.


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## Arossihman (Jan 29, 2012)

shortround6.....
I would say original specs....later aircraft were modified to fix shortcomings like range and climb rate. If i were to use the p-47n for example they had good range. So lets stick to originals for now and maybe later we can morph it into something else.
Tony


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## Arossihman (Jan 29, 2012)

parsifal said:


> Spitfire: Its limited range and limited fighter bomber capabilities. Feels like I am blaspheming when I do this



I know what ya mean!


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## futuredogfight (Jan 29, 2012)

The p-36 lacked the choice to leave the battle at will


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## Shortround6 (Jan 29, 2012)

Was the original P-47 designed to be an escort fighter? If not then what is the Problem? Did it have equal or greater range than the P-40? The Initial design for the P-47B was offered to the Army in June of 1940 and the contract for the prototype placed in Sept 1940, during the BoB. What was the original range or endurance requirement? The fact that the ASAAC wanted escort fighters 3 years later doesn't mean that the P-47 failed to meet it's original goals.


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## Siegfried (Jan 29, 2012)

Me 109. For the same power it was faster than and could outclimb just about any fighter. However for various reasons the Germans fell behined in power between late 42 and early 44.


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## Shortround6 (Jan 29, 2012)

parsifal said:


> Spitfire: Its limited range and limited fighter bomber capabilities. Feels like I am blaspheming when I do this



It was designed to be a short ranged interceptor. Carrying extra fuel and having fighter bomber capabilities would hurt it's interceptor abilities. Please remember that the British, for what they considered good and proper reasons ( but then they drink warm beer) decided that their fighters should use fixed pitch propellers and single speed supercharged engines in the late 1930s while the bombers got the two pitch or constant speed propellers and the two speed super charged engines.

The difference in take off performance of the propellers alone is staggering. take off run dropped from 420 yds with the fixed pitch to 320 yds with the 2 pitch to 225 yds with the Rotol propeller. Take off to clear a 50 ft obstacle went from 790 yds to 490yds to 370 yds. The Rotol equipped plane could be at 50ft before the fixed pitch plane got it's wheels of the ground. It took 6 minutes less to get to 30,000ft too. If the fighters had been given constant speed propellers earlier then maybe more weight could have been used for secondary roles without compromising performance too much.

edit> having the best all round fighter in the world doesn't do much good if it can't take-off from most of your existing air fields.


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## drgondog (Jan 29, 2012)

The Mustang B/C/D had a couple of serious issues - namely vicious high G stall/spin characteristics, more vulnerable to 'golden B-B' with underslung radiator/oil cooler and glycol lines, some structural issues in High G diving roll, and for the B/C gun jamming from both high G stresses as well as marginal gun heater.

It can be a beast in a severe cross wind landing - and do NOT ditch the airplane.


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## herman1rg (Jan 29, 2012)

Shortround6 said:


> ( but then they drink warm beer) .



Not all of us do!!


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## parsifal (Jan 29, 2012)

For the Spitfire, maybe we should add "poor choice of prop and supercharger for the earlier marks".

Design choices are design choices. For the Spit, like anything else, compromises had to be made. For me, and i admit this is open to interpretation, the Spuit was thje best all round fighter in 1938-40. but a price had to be paid for that, and that eventually had an effect on operations for the aircraft and indeed the RAF as a whole. Because the Spit (and all the other RAF SE fighters of the time) could not fly all the way to Germany, the RAF had to fly its bombers at night . Later, when the FC swung opver to the offensive, Spits could not really operate in the FB role very well.


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## Shortround6 (Jan 29, 2012)

There are all kinds of 'official requirements" in the 1930s that disappeared real quick when the actual shooting started that affected aircraft designs. The British even had a limitation on maximum tire pressure to avoid causing ruts in the grass air fields. It was the same maximum for all aircraft types so it is rarely, if ever mentioned in individual requirements. It may be a small thing but several small things add up, the landing field requirement was a big thing in the 30s too. Even the Blenheim bomber was practically a STOL machine. 
You have to also look at what was possible at the time. The power to weight ratios of the available engines in 1938-40 simple didn't allow a single engine fighter to carry enough fuel to fly long distances and still perform well enough to handle a short ranged fighter. The Zero was the only fighter to pull that trick off and it required some sacrifices and an element of luck. Luck in the form of well trained, experienced pilots going up against mostly Green pilots and often a rather disorganized defense. Imagine Zeros trying to fly from England to Points in Germany (even if not Berlin) in the Spring of 1942 and think how well they would have done? 

many people do not really appreciate the changes that better fuel ( and engines ) made. Every body (mostly ) knows about 100 octane fuel but the timing and what it meant to engine operations and aircraft performance is remarkable. Considering the time it takes to get an aircraft from design to large scale service use, just about ALL aircraft (basic airframe)used up until 1942 were designed with 87 octane fuel in mind. granted many of them used 100 and 100/130 fuel to great advantage. 

The octane scale is not linear. The performance number scale is much closer to being linear and indicates what an engine could expect to do for *internal* horsepower, that is the power developed in the cylinders before subtracting friction, pumps and supercharger drive requirements. 100PN = 100 octane. 100/130 should allow for about a 30% increase in power (not all engines responded the same and the range could be from 20-40% increase). 150 PN means a 50% increase over 100PN. 
Now going the other way, to see where the late 1930s aircraft designs came from with the expected available power you have 91 octane fuel having a PN of 75.68, while 87 octane has a PN of 68.29 and 80 octane fuel has a PN of 58.33. 
With an engine running on 87 octane instead of 100 the engine might see a drop of around 30% in power. (it will be less difference at the crankshaft because to make full use of the 100PN fuel more boost needs to be used which means more power used in the supercharger). Obviously such changes in engine power for little differences in weight mean big changes in aircraft performance including lifting more fuel for longer range.


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## buffnut453 (Jan 29, 2012)

P-51 limitation would be jams to the ammunition feeds. Same-same for the F4F.


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## Jabberwocky (Jan 30, 2012)

FW-190A series: Poor altitude performance, poor engine reliability in initial marks

Hawker Typhoon: Poor engine reliability, buckling/loss of tailplane (26 known incidents), leakage of Co2 into cockpit forcing pilots to permanently wear oxygen masks, thick wing harming altitude performance and leading to high-altitude problems with compressibility

Spitfire I/II/early V Hurricane I/early Mk IIs: Problems with Merlin float carburetor lead to cut-out in negative G

de Havilland Mosquito: Wing shedding problems (occurred in 1944 and fixed later that year). NOT due to warping or delamination due to heat/humidity - as oft repeated - but actually due to a manufacturing defect at one of the factories, relating to how the wing skin was attached to the main spar. European Mosquitos suffered more wing failures than Far Eastern Mossies did. 

P-51B/C: Problems with gun jamming, rectified with introduction of P-51D

Seafire: Poor arrestor frame arrangement leading to high crash/write off levels during carrier ops;

Bf-109: Narrow track and camber of landing gear;

Me-110: Slow rate of roll, particularly at low speeds

A6M: Slow rate of roll, particularly at higher speeds. Control forces at high speeds were very high (also affected early Spitfires, Hurricanes, Bf-109s and many other fighters with fabric skinned ailerons). Japanese pilots often removed radios, particularly on long-range missions. Lack of self sealing fuel tanks in early models. Low limiting dive speed, improved incrementally through the war with improvements to wing skinning and other mods.

He-177: Prone to engine fires, a problem gradually fixed throguh the war.

FW-200: Prone to breaking at the spine during landing


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## MikeGazdik (Jan 30, 2012)

So many favorites, but to start. P-39- single stage Allison, 37mm cannon. P-40 - single stage Allison, P-51A - single stage Allison. (theme here?) P-47 range, weight. F4U Corsair, my longest answer. I feel when the cockpit was moved aft, the pilot was then placed in a bad spot in the fuselage. I have seen photos where the rear of the air frame from the pilot seat back twists or breaks away from the wing and forward structure. Bad for a hard crash landing. F6F Hellcat too slow, for all the go under the hood. F4f, landing gear off an Army duece and a half. Me 109-landing gear and weak wing, Fw190-should turn better for its weight. Spitfire- um, uh, its too pretty to talk bad about!!!!


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## Bernhart (Jan 30, 2012)

carburators in early hurricanes and spits


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## buffnut453 (Jan 30, 2012)

parsifal said:


> Spitfire: Its limited range and limited fighter bomber capabilities.



I agree that the Spit's range was limited compared to other fighter aircraft but it must be remembered that, at the time of its creation, there was no requirement for longer-range operations. Also, there was no concept of a "fighter bomber" in the 1930s - that was a tactical evolution that occurred during WWII. 

Perhaps we need to tighten the question a little and simply examine achilles heels that were related to the aircraft's initial intended role?


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## Shortround6 (Jan 30, 2012)

buffnut453 said:


> I agree that the Spit's range was limited compared to other fighter aircraft but it must be remembered that, at the time of its creation, there was no requirement for longer-range operations. Also, there was no concept of a "fighter bomber" in the 1930s - that was a tactical evolution that occurred during WWII.



Actually the fighter bomber dates back to WW I. Many British fighters were given bomb racks for four 20lb bombs. This continued on into the 1920s and a number of American fighters of the late 20s and 30s also had racks under each wing for light bombs. The P-26 could carry four 50lb bombs under the center section. The He 51 could carry six 22lb bombs inside the fuselage. I am sure there were others. Curtiss was advertising a total bomb load of 850lbs for export 75 Hawks, I don't think anybody took them up on it. The basic problem until WW II was the fighter had enough trouble just flying as a fighter without trying to strap a big bomb load to it. With 450-600hp for a late 20s/early 30s fighter and a all up weight of under 4,000lbs trying to carry a 500lb bomb just wasn't going to work without using a really big wing that would kill fighter performance once it was dropped. 



buffnut453 said:


> Perhaps we need to tighten the question a little and simply examine achilles heels that were related to the aircraft's initial intended role?



I think that is a good idea, perhaps two categories? 

Early Spitfires had elevators that were too powerful and were hard to coordinate in maneuvers. Later Spitfires were shorter in range than they could have been given that several schemes for adding fuel tanks had been used in limited numbers. Granted it would never equal the Mustang.


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## TheMustangRider (Jan 30, 2012)

The P-51's CG issues due to the implementation of the aft fuselage 85 gallon fuel tank deserves a mention.
A bothersome tendency that forced its pilots to get rid of some of that fuel en route before engaging the enemy.


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## Arossihman (Jan 30, 2012)

Shortround6 said:


> Was the original P-47 designed to be an escort fighter? If not then what is the Problem? Did it have equal or greater range than the P-40? The Initial design for the P-47B was offered to the Army in June of 1940 and the contract for the prototype placed in Sept 1940, during the BoB. What was the original range or endurance requirement? The fact that the ASAAC wanted escort fighters 3 years later doesn't mean that the P-47 failed to meet it's original goals.


 
I have a book at home that can answer that question but i know it was not designed as an escort fighter....however it still lacked by comparison to some of its competitors in climb rate. Although it did live up to army requirements in airspeed,armament,armor, and self sealing tanks,they came up a few gallons short of the capacity requirements for fuel. Granted it would'nt have made much difference in range i feel it was still a minor shortcoming as it could be the difference between ditching in the channel or making an emergency landing in some guys field! Don't get me wrong here to me the p-47 embodies all that i love in a fighter and to me in good hands it can do no wrong, but the early versions had their shortcomings.


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## pbfoot (Jan 30, 2012)

Lack of de icing equipment on Lancaster and halifax , like how stupid is that sending out heavy bombers at night with no deicing but I guess that extra couple of hundred lbs made the difference, most of the crews wouldn'y even know they were icing as they were hopefully flying in darkness , and using a flashlight to peer out if your icing would be a invite for an attack


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## davebender (Jan 30, 2012)

There's no such thing as a free lunch. If you want the P-51 to have extreme endurance all that internal fuel will degrade flight performance.

The late war P-47D-15 carried 375 gallons of internal fuel. That also must have degraded flight performance to some extent. However the jug was such a heavy monster to begin with that additional fuel weight might not be as noticable.


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## Milosh (Jan 30, 2012)

TheMustangRider said:


> The P-51's CG issues due to the implementation of the aft fuselage 85 gallon fuel tank deserves a mention.
> A bothersome tendency that forced its pilots to get rid of some of that fuel en route before engaging the enemy.



Not just the P-51 had this issue, the Spitfire did also when fitted with the rear fuselage fuel tank.


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## Shortround6 (Jan 30, 2012)

The question as to the fuel affecting the performance of the P-47 is different than the how it affected the P-51. The P-47B (none used in combat) and the "C" early "D"s had 305 US gallons. They also started with 2000hp engines and the famous "toothpick" propeller. When the later models went to the 370-375 gallon tank it was an enlarged tank in the same place and affected the center of gravity little if any. The later models also had engines that were good for 2300-2500hp and had the paddle blade props. With the P-51 the extra fuel went behind the cockpit and had a serious affect on the center of gravity. Extra weight can certainly affect a planes performance but changes in the center of gravity can affect handling and or trim and control response.


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## Readie (Jan 30, 2012)

Interesting posts.
'Warm beer'..ummm 

The Spitfire had some Achilles heels. carburettors... Mind you Miss Shilling's orifice sorted that out.
Shilling devised a simple, yet ingenious, solution that was officially called the R.A.E. restrictor. This was a small metal disc with a hole in the middle, fitted into the engine's carburettor. Although not a complete solution, it allowed RAF pilots to perform quick negative–g manoeuvres without loss of engine power. By March 1941, she had led a small team on a tour of RAF fighter bases, installing the devices in their Merlin engines. The restrictor was immensely popular with pilots, who affectionately named it 'Miss Shilling's orifice' or simply the 'Tilly orifice.' It continued in use as a stop-gap until the introduction of the pressure carburettor in 1943.

As a combat aircraft, the Spitfire's flying performance against that of its foe was obviously of fundamental importance. Until the autumn of 1941 its main adversary was the Messerschmitt. The two were fairly evenly matched, the Spitfire being more manoeuvrable and faster at low level but the ME 109 better in the climb and slightly faster at a higher altitude.
Their respective engines also behaved differently. The Messerschmitt's fuel-injected Daimler-Benz engine did not have the disadvantage of the Spitfire's float-type carburettor causing the engine to cut out during certain manoeuvres. Another weakness of the Spitfire was the heavy stick force the pilot had to contend with from the ailerons when flying at high speed. Although the plane's design was under constant development throughout the war, this aspect was never properly cured.

The Spitfire had a fuel tank directly in front of the pilot, between the engine and the cockpit. The high-octane fuel used in high intensity air combat put the pilot at high risk. A single enemy bullet could ignite the fuel, filling the cockpit with roaring flame. The pilot's only escape was to pull back the canopy and flip the plane upside down in the hope of a safe escape by parachute, all in the space of about eight seconds. Many suffered horrific burns, their hands and faces completely erased by fire. The injury was given its own name – Airman's Burn – and led to the development of new forms of severe burns treatment by the RAF surgeon Archibald McIndoe at a cottage hospital in East Grinstead. His patients were to form the now celebrated Guinea Pig Club which still exists to this day.

By the time the The Mk V design was introduced early in 1941 the Spitfire had become the full equal of the Messerschmitt Bf-109F, and various modifications were available for different fighting conditions. These included extended or 'clipped' wing tips for high or low altitude performance, sand filters for the North African desert, and various combinations of both cannons and machine guns (some even carried bombs). The carburettor was also improved to prevent engine cut-out under negative 'G'.

I am going to have a lie down in shock as I have had to admit that my much loved Spitfire was not 101% perfect...

John


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## drgondog (Jan 30, 2012)

Spitfire aileron ineffectiveness at high speeds ~ 33% at 400 mph (compared to a Mustang/P-47) - were a problem against the 190's.. but fixed later in the series


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## krieghund (Jan 30, 2012)

The Zero for all the usual well highlight faults...however, not starting with the Kinsei engine instead of the Sakae. Would have progressed to the Kinsei 62 in 1942 instead of 1945

Of course we could what if? all day long.......


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## TheMustangRider (Jan 30, 2012)

Milosh said:


> Not just the P-51 had this issue, the Spitfire did also when fitted with the rear fuselage fuel tank.



To which Spitfire Mk are you referring to Milosh?
Much has been written (or perhaps I've read) about the Mustang's 85 gallon fuel tank but not much about the Spitfire's as far as I'm aware.


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## Juha (Jan 30, 2012)

Hello MustangRaider
Late Mk IXs and XVIs etc could have two rear fuselage tanks one on the top of another, 33+33Impgal in teartop canopy versions and 33+41Impgal in traditional highback versions.

Juha


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## drgondog (Jan 30, 2012)

Worth noting is that the 85 gallon tank was at first a field modification under direction of 8th AF, beginning in March 1944. Hard to describe as an "Achilles Heel' - at least for the Mustang. It wasn't a production standard until middle of -7 series.

It may have been the Achille's Hell for the Luftwaffe by enabling the extended 300 miles cruise range or another 15 minutes of combat.

The solution wasn't difficult, and available on every mission just by burning it early down to 25 Gallons or less early in the mission. The general over ride to that SOP was the ultra long range mission when drag was a factor - then burn the external tanks before switching to the fuselage tank... like the Shuttle missions.


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## chris mcmillin (Jan 30, 2012)

I think that the early ops of 8th AF fighters in the UK were severely hampered by the fact the USAAC had an order against droppable fuel tanks. 

The P-47 had good range once wing pylons were used and fuel systems were plumbed for the use of these tanks but it took crucial time. The belly drops on it weren't very capable. 
The P-38 and the P-47 were capable of operating with bombers all the way to the target and back with Lockheed 150 gallon drops, but weren't capable of doing it until the P-51 showed up. Why it took so long with the Lockheed I don't know, it always had the drops, under the guise of "long range ferry tanks".

Also, the P-51 B/C didn't start with the rear fuselage tank, and it came in two sizes. The large 85 gallon was installed later in the B/C series and all D's had it. 
The airplane had directional stability problems, nothing to do with the razorback to bubble change, and the dorsal fin was for structural deficiency when yawing and rolling at high speeds. With aft CG it was made even worse. 
The trim tab on the rudder was an anti-servo tab when in service so the rudder was harder to push than when used as a straight tab as it was converted to after the war, directional stability in ops when full fuel and in instrument flight being the driver here, especially with low time pilots in command.

The Mustang was and is a great airplane but it had a lot of work done to it during it's development. All of the WWII airplanes went through a phenomenal development to good fighting machines in an incredibly short period of time.

Chris...


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## drgondog (Jan 31, 2012)

chris mcmillin said:


> I think that the early ops of 8th AF fighters in the UK were severely hampered by the fact the USAAC had an order against droppable fuel tanks.
> 
> *Chris - when the tanks became available, the order was to 'bring them home' because they were in scarce supply. Most Group CO's told their pilots to ignore the order if they needed to drop to engage or evade German fighters.*
> 
> ...



"Also, the P-51 B/C didn't start with the rear fuselage tank, and it came in two sizes. The large 85 gallon was installed later in the B/C series and all D's had it."

Chris - I am only aware of the 85 gallon mod to the P-51B-1 and -5's (and early -7s) done in mid March 1944. I have heard of filling the tank to only 65 gallons but even that was stopped when too many 'under fill's occurred. From middle block of P-51B-7 through P-51D-30 NA (and matching NT) all the factory tanks were 85 gallon. Only the H had a factory 50 gallon tank.


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## renrich (Feb 3, 2012)

Another issue with the early F4F3 was that the fuel gauge was notoriously inaccurate and the early protected fuel tank's linings caused fuel lines to get stopped up. UGH!


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## TheMustangRider (Feb 3, 2012)

Juha said:


> Hello MustangRaider
> Late Mk IXs and XVIs etc could have two rear fuselage tanks one on the top of another, 33+33Impgal in teartop canopy versions and 33+41Impgal in traditional highback versions.
> 
> Juha



Thanks for the information Juha.


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## Edgar Brooks (Feb 3, 2012)

**


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## fastmongrel (Feb 3, 2012)

Edgar Brooks said:


> ; the tanks necessitated clipped wings, so were only used for the low-level "bubble-top" XVI F.R.XIV.



What was the problem with the tanks that necessitated clipped wings. Was it a fix for the C of G shifting aft.


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## Edgar Brooks (Feb 3, 2012)

--


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## pbfoot (Feb 3, 2012)

The one fault that was probably the cause of more young mans deaths , the lack of de icing equipment on the Brit heavy bombers was almost criminal


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## Readie (Feb 4, 2012)

pbfoot said:


> The one fault that was probably the cause of more young mans deaths , the lack of de icing equipment on the Brit heavy bombers was almost criminal



Quite right Neil. Another example of British cynicism
John


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## Juha (Feb 4, 2012)

Hello Edgar
thanks for the info!
but


Edgar Brooks said:


> ... The reduction in armament needed the gyro gunsight to give the pilot a better chance to actually hit something, which needed a new throttle box, and had to be fitted before the tank went in; the extra fuel (as you say) made the airframe extremely touchy to fly, which was another reason for 11 Group's distaste, since it badly affected their ability to work as escorts.
> All of these changes took so long that not a single low-back fuselage Spitfire saw service before 1945, which was another reason for not converting the high-backs, which were needed for straight fighter/escort work.



I understand the first part but IMHO 2 .5 HMGs nearer the fuselage was an improvement over 4 .303mgs far out, especially after 41 when self-sealing fuel tanks and pilot armour were the norm. Gyro sight was a clear plus irrespectively whether one had C or E wing. And as in P-51, rear fuselage tank(s) made the plane difficult to handle first but it also allowed the plane fly farther or stay longer, which was important in escort work, but because RAF had also Mustang IIIs and IVs, there well migh have not been great need for longer range Spits. But a fighter which could escort bombers only part of way to their targets was not worth of much as an escort. As an interceptor of course extra weight reduced RoC.

Juha


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## nuuumannn (Feb 4, 2012)

> I am going to have a lie down in shock as I have had to admit that my much loved Spitfire was not 101% perfect...


  Can I offer you a stiff drink, John?

Regarding the Bomber Command aircraft; arming them with .303s instead of .5s sooner in the war; both Boulton Paul and Rose developed a .5 armed turret during the war but these were not fitted (the BP turret was post-war). Even 'Bomber' Harris was highly critical of this aspect of 'his' bombers. 

I read an interesting thing in a book recently about gunners were discouraged from firing at enemy night fighters for fear of giving their position away! I'm astounded by this, since I also read an account by a German Bf 110 pilot who claimed that many of the bombers did not fire back, even after he had attacked them; he stated that had the bombers fired off a stream every time he approached, he would not have continued his attacks on many occasions. 

The Halifax is worth mentioning for how bad it was in its initial versions (including the Mk.V) until the Mk.III came along with its bigger rudders, streamlined nose, Hercules engines and other changes, which brought its performance closer to the Lancaster, but still not on a par with it, despite Handley Page's assertions. It had rudder over balance, which resulted in the loss of life of service and test personnel, weak undercarriage, it was heavy, draggy and underpowered and could not meet its stipulated performance. Harris proposed that Stirling and Halifax production be canned and those two manufacturers build Lancs.

Some of my favourites: The Me 163 - what can I say but the only thing in its favour was that it was horrendously fast!

The Boulton Paul Defiant - slow, but deadly to a bomber stream; unfortunately not used in its designed capacity, so suffered at the hands of single seat fighters. Excellent night fighter, though.

The Mitsubishi Zero; I spoke to a guy who flies one of the airworthy ones and he said one of its biggest weaknesses is that it wasn't very fast, so could easily be overhauled in a dive. Weak construction, but this contributed to its greatest advantage, however. 

The Fairey Swordfish; obsolete and antiquated, but all the more charming as a result. Its aircrews seemed to agree!


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## Edgar Brooks (Feb 4, 2012)

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## MikeGazdik (Feb 5, 2012)

Edgar Brooks said:


> I've been digging out more information on the .5" versus .303" controversy; Leigh-Mallory tried his hardest to get the change, but the Air Ministry flatly refused, since the .5" (no matter what people think) had no advantage over the .303" from directly behind the Fw190 (Fighter Command's chief worry.) To make the .5" effective, the pilot needed to use a 5degree deflection shot, at the very least, and, as with the bomber turret, four faster-firing guns had more chance of killing the pilot than two. The same thing applied though; once the gyro gunsight was available for fighters, the .5" made more sense. Eventually, in 1943-onwards, the Spitfire XIV was available, with more internal fuel, plus the ability to carry droptanks, and, once the Allies were in Europe, distances weren't critical any more; it's also worth remembering that, with most bombing done at night, Bomber Command didn't need escorts before 1944, when more daylight raids began to happen.



The destructive power of the .50 cal, over the .303, versus the airframe has to be far greater. I agree that a .303 will kill a man just as dead as the .50. I understand the volume of fire argument, but how many fighters shot down were due to dead or incapacitaed pilots versus the aircraft being damaged beyond continued flight?


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## Juha (Feb 5, 2012)

Edgar Brooks said:


> I'll need to answer two, for the price of one, here; the retention of .303" guns, in bombers, was for exactly the same reason as they were retained in fighters. More guns, with a faster rate of fire, gave more chance of hitting the enemy pilot, who very rarely had any armour in front of him, and a .303" through his head is just as lethal as a .5". The Rose turret, with the .5" guns, only came into use when the rear gunners also got the use of the gyro gunsight, and thus had a better chance of hitting what they were aiming at...



Hello Edgar, the point is that in both 109 and 190 pilot had armoured glass, which usually stopped .303 bullets but was less effective against .5 bullet, in front of him. Engine did the rest of shielding from front (+plus oil collar armour in 190A). Now against 109 with liquid-cooled engine .303 might well be enough but against air cooled radial IMHO .5 probably was more effective than 2 .303s. Tail turrets were a bit different thing, firing distances were usually fairly short at night and up to late 44 vast majority of LW night fighters were 110s and 88Cs with liquid-cooled engines, so a burst from 4 .303s could easily knock out an engine.



Edgar Brooks said:


> I've been digging out more information on the .5" versus .303" controversy; Leigh-Mallory tried his hardest to get the change, but the Air Ministry flatly refused, since the .5" (no matter what people think) had no advantage over the .303" from directly behind the Fw190 (Fighter Command's chief worry.) To make the .5" effective, the pilot needed to use a 5degree deflection shot, at the very least, and, as with the bomber turret, four faster-firing guns had more chance of killing the pilot than two. The same thing applied though; once the gyro gunsight was available for fighters, the .5" made more sense...



Finns though otherwise and began to install at least one .5 HMG cowling gun to their Hawk-75As early on, just to have something to pierce back armours and saw that one HMG was better than 2 .300/.303.




Edgar Brooks said:


> Eventually, in 1943-onwards, the Spitfire XIV was available, with more internal fuel, plus the ability to carry droptanks, and, once the Allies were in Europe, distances weren't critical any more; it's also worth remembering that, with most bombing done at night, Bomber Command didn't need escorts before 1944, when more daylight raids began to happen.



Now even if XIV had more fuel than standard IX it also had more thirstly Griffon, and already Mk V had had ability to carry drop tanks. But clearly RAF didn't though that Spit critically needed more range in ETO otherwise they would have kept some longer range VIIIs there and not sent them all to MTO and to Far East.

Juha


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## Edgar Brooks (Feb 5, 2012)

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## Juha (Feb 5, 2012)

Hello Edgar
IMHO no hindsight, USAAC and USN opted for .5 already between the WWs, most USAAC fighters had one .5 and one .300 cowling guns in 30s, Finns decided in 41 that it was preferable to install one .5 instead of 2 .300/.303. And for ex German ace Fönneköld? was killed by a .5 AP staight through the back armour of his 109G. Even if RAF seemed to prefer 4 .303s over 2 .5s, and I'm not sure of that, it might well have been a case to make virtue out of necessarity because US needed almost all of .5s it produced up to 44, but US, SU, Italy all thought that .5 was clearly better than .300/.303. Even JAAF and JNAF dumped .303 and went to .5 (and cannon) fairly early in the Pacific War.

Juha


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## Edgar Brooks (Feb 5, 2012)

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## drgondog (Feb 5, 2012)

Edgar - I see nothing but speculation in 2. and 3. A Browing .50 has nearly 4 time the KE of a .303 at the Muzzle and ranges for defense in RAF night ops were short relative to USAAF day operations. So it would be interesting (to me) to see a firing test against an FW 190 at 100 yards with both weapons.

Absent testing validation (presumably there is something somewhere in your report) the comparison of .50 cal and .30 cal (or .311) at 100 yards should be immensley in favor of the M2/M3 hitting an FW 190 or 109 or 110 head on. The Sturm FW had more frontal and side armor to protect the pilot (true) but if a .50 API couldn't do the job a .303 was hopeless.

Next - head on hits on an FW 190 to the oil cooling vanes is an Achilles Heel. It will go down soon if not immediately due to an oil fire.

Next - a .50 will definitely destroy an engine, penetrate into ammo storage and IMO have a far greater chance of critically damaging a wing spar with one hit than a .303 with multiple hits.

Last but not least - what are the percentages of FW 190 intercepts on BC aircraft versus Me 110, Ju 88, etc that did not have the same protection up front of the modified Fw 190s attacking 8th AF formations?

I realize I am offering opinions that may be trashed by a well thought out series of comparative tests but ballistically speaking there is simply no useful benefit to two .303's versus one .50 caliber HMG. Even the ability to carry a lot more .303 rounds is kind of silly considering how few opportunities to engage in prolonged fights at night. 

If that was a serious consideration I would have immediately moved to single 20mm to replace four .303's


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## renrich (Feb 5, 2012)

I have read that the RAF wanted to replace the 303s on British bombers with 50 BMGs but the 50s were not readily available so they soldiered on with the 303. Comparing the 50BMG with the 303 as far as overall lethality is ridiculous. Against aircraft, lightly armored vehicles, lightly armored ships, there is no comparison..


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## Edgar Brooks (Feb 5, 2012)

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## pbfoot (Feb 5, 2012)

I've read more then once about gunners that would not fire there 303's because they were worried that it would wake up the LW pilot who was unaware of them


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## drgondog (Feb 5, 2012)

Edgar Brooks said:


> Unfortunately, the Germans didn't often drop a Fw190 into the U.K., in such a state as to enable us to use it for destructive testing (they had to ship a hulk back from the Middle East.) Complete aircraft were used for combat training. The usual firing range/synchronisation was 250 yards, not 100.
> 
> *The usual range for a german nightfighter was 150 yards or less. A night fighter would be extremely difficult to see, much less hit at 250 yards in a blacked out night, and when approaching from low aft even more difficult. Why would BC harmonize at 250 yards. I'm not disputing your claim - it just seems to be a stupid policy for tail and mid upper gunners to harmonize way past their average shooting range based on seeing their target - PARTICULARLY if standard practice was to wait until the German fighter started shooting?.
> 
> ...



First - the ability of the Spit to mount and carry 4x 20mm was never limited by engine power. As an example the P-51 (pre P-51A and Mark I) had 4 x 20mm with an 1100 hp engine and heavier than the Spit (all marks). It would have been easy to install 4 x20mm in the P-51B/C/D without suffering significant performance loss - particularly in contrast with the 6x 50 P-51D. Wing design was primary issue with Early Spits - not Rolls Royce engine.

Your extra weight argument is spurious. The LW suffered equally from the slightly more agile four .50 B/C Mustang as it did from the 600 pound heavier P-51D with 6x.50 ( two extra 50 cal plus 400 more rounds of ammo) - and that delta weight was FAR more significant than the adding say twenty x .50 cal to a Lancaster.

Look, this argument loses all basis for anything but opinion absent tests to demonstrate what the US Army knew from 1918 to present day. The Browning M2 and M3 .50 Caliber heavy machine gun is a far more powerful and effective anti armor, anti aircraft weapon than the M1919 30 (30-06 vs .303). The .50 breaks engine blocks, penetrates through 2x armor plate at any range - and increases the advantage with range.

I absolutely think leigh-Mallory was 100% correct in his views and surprised he didn't simply declare victory on the subject.


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## Glider (Feb 5, 2012)

Edgar Brooks said:


> The idea was dropped, for the "standard" version, since 11 Group's commanding officer objected to the loss of height and rate-of-climb, when his fighters were being used for escort work; the tanks necessitated clipped wings, so were only used for the low-level "bubble-top" XVI F.R.XIV.



As far as I am aware the idea wasn't dropped. Far from it, 800 fuel tanks were ordered for retro fitting into existing Spit IXE and teardrop mk IX's had them installed as standard.


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## Glider (Feb 5, 2012)

Going back to the idea behind the thread, My favorite plane would be the Whirlwind and its weak spot, only 60 RPG.


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## Juha (Feb 5, 2012)

Edgar Brooks said:


> I have pages of the back-and-forth arguments between Leigh-Mallory and the Air Ministry hierarchy, which you're welcome to see, but there are too many to put them on here. L-M wanted them, the A.M. said no, and gave their reasons, which had nothing to do with production, or availability, of the.5".
> Edit: This is typical of the response that L-M received:-



Thanks a lot, Edgar
always love to see original docus!

IMHO according to the few reports/memos I have seen on British armament tests they were realistic. IIRC at first British concluded that .5 Browning AP bullet was incapable to penetrate the back armour in LW fighters but later changed their mind. I cannot remember was it simply that later tests gave different results, penetration ability of a bullet after first coming through even light structures is a bit unpredictable, or had US designed a better AP round between the tests. IIRC US designed, or copied a Russian one, clearly better .5 AP/I round during the war.

Juha


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## Edgar Brooks (Feb 5, 2012)

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## Edgar Brooks (Feb 5, 2012)

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## Edgar Brooks (Feb 5, 2012)

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## Glider (Feb 5, 2012)

Edgar Brooks said:


> No they weren't. Modification 1335 was cancelled, as a general item, and only instituted for the XVI, as it was being built, because they were only ever intended for low-level use (like the F.R.XIVe, the only other wartime Mark to carry them.) The other necessary mods were too complicated, and time-consuming, to justify their inclusion. As it was the XVI only saw about three months of use, in 1945; no low-back Spitfire, of any Mark, was cleared for use before the end of 1944.
> ADGB also pointed out that the necessity to "fly off" a sizeable gallonage, before they could go into combat, meant that, effectively, their range only increased by about 75 miles. With airfields available in freed parts of Europe, the extra range meant little, and droptanks were still the best option (apart from the risk of being blown up by a single incendiary round in a fume-filled tank.)
> To give you an idea of what was thought of them, post-war, Squadrons were banned from using (or even filling) the XVI's tanks.



Do you know when this was cancelled. I say this as I have a number of papers that would appear to disagree with your position.


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## bobbysocks (Feb 5, 2012)

the p 39 had a couple bad habits...early ones anyways. sometimes the pilots would get exhaust fumes in the cockpit. not a big deal if you are flying at altitude where you need O2 but was a pain if you were down low and off air. also it had a bad knack of tumbling...and once it started there was no pulling it out.

early 38s had horrible cockpit heaters i understand...which isnt itself isnt a big deal but remember a story where the pilot couldnt get his canopy defrosted...THAT could make life interesting.


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## Milosh (Feb 5, 2012)

The only fighter that had protected ammo boxes that I can think of was the Fw190A-8/R8 that had outer wing mounted MK108 cannons.



> Precisely what was being said, (14mm armour protected the Fw190 pilot's head,)



The Fw190A-8 had 8mm seat armour, 5mm back and panels on bulkhead 5 armour and *12mm* head armour for the pilot.

Mod 1335 was for the standard fuselage and Mod 1414 was for the rear view fuselage.

How did the .50"s ever shoot down an a/c if the broke up on an a/c's skin?

Didn't some Spitfire Vs arrive on Malta with 4 20mm wing cannons?


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## MikeGazdik (Feb 6, 2012)

1) I don't see this as anyone yelling at Edgar Brooks, just disagreeing with the opinions in the documentation you provided.

2) Back on point; All of the Russian made fighters that were severly under-gunned.


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## parsifal (Feb 6, 2012)

> All of the Russian made fighters that were severly under-gunned


.

True, when compared exclusively with german machines. That relative weakness is more than just a function of light armament. The 20mm SHVAK was relatively light on ballistically.

however, compared to some other nationalities, such as the italians, the Soviet aircraft were reasonably well armed


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## Edgar Brooks (Feb 6, 2012)

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## Edgar Brooks (Feb 6, 2012)

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## Juha (Feb 6, 2012)

Hello Edgar
thanks again for the docu!



Edgar Brooks said:


> ... in 1943 the Spitfire IX was being delivered direct from Gibraltar to Malta the desert, and signals talk of internal tanks being carried, together with the 170-gallon ferry tank, but I don't yet know what form those tanks took, so it's possible that they were the same type, but only possible.



Can't say anything on Mk IXs but when some Mk VCs were mod. for non-stop flights from Gibraltar to Malta, they got 29 gal rear fuselage tanks and larger oil tank, armament reduced to only 2 .303s. Equipped with a 170gal ferry drop tank so mod Mk VC could fly that just over 1,100 mls trip. When the planes arrived, the rear fuselage tank was removed, larger oil tank was changed to the normal one and they got their normal armament.These ferry flights began in Oct 42
. This info can be find from both Price's The Spitfire Story and Morgan's and Shacklady's Spitfire The History.
Juha


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## drgondog (Feb 6, 2012)

Edgar Brooks said:


> There's a 7-page assessment of the probability of destruction of a Fw190A-3, by a direct stern attack, and the .303" .5" both came out with a 0% probability rating, since, as well as the pilot's armour the bullets would have oxygen tanks, tail wheel oleo, and wireless to get through, first; it also says that, with a slight deflection shot of a few degrees, even the .5" shells would be deflected, even broken up, by the fuselage skin. In the files, there is mention of work, under way, to produce a projectile that doesn't get deflected, or broken up, but, so far, I haven't found out if it actually happened.



It is simply amazing that the 1968 FW 190's Credited as Destroyed by 8th AF managed to clumsily blow up, crash or simly be abandoned as a result the application of .50 caliber rounds as puny as the RAF report suggests...


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## Edgar Brooks (Feb 6, 2012)

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## MacArther (Feb 6, 2012)

The Curtiss P-40 from the E Model on.....Do I really have to list all the issues that went wrong with this plane?


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## Edgar Brooks (Feb 6, 2012)

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## renrich (Feb 6, 2012)

The 50 BMG "skidding off" of aircraft fuselages??? Now I admit that this was 1960 and maybe the projectile was different. I believe that our ammo was just normal ball (full metal jacketed) and I fired the new M60(7.62 Nato, comparable to the 303 British) and the 50 BMG at old vehicles on the range at Fort Hood. The difference in the two rounds was spectacular. On old half tracks and 2.5 ton trucks the 50 tears big gaping holes and will go all the way the body work from one side to the other. No way a WW 2 AC has heavier body skin than a truck.


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## drgondog (Feb 6, 2012)

Edgar Brooks said:


> Oh, please, do get down from your white-charger-riding-to-the-rescue-of-the-wagon-train, and try reading what was said. The RAF/Air Ministry said that, until the GGS arrived, the .5" gave no advantage over the (already in use) .303". Nowhere have I seen the word "puny" used, nor is it implied, so stop putting words into the mouths of the inspection teams.
> The .5" gave no extra hitting power because the average RAF pilot couldn't master deflection shooting past a few degrees, and both the .5" AND the .303" both seemed likely to skid off the rear fuselage, at low angles, so what was the point of adding extra weight (one .5" + ammunition weighed more than two faster-firing .303" + their ammunition) for no gain in killing power?
> 
> 
> ...



Edgar - the reason we got into this debate is that you personally departed from simply quoting an RAF unit's perspective in a debate with Leigh Mallory into your own perspectives as noted below:

*I've been digging out more information on the .5" versus .303" controversy; Leigh-Mallory tried his hardest to get the change, but the Air Ministry flatly refused, since the .5" (no matter what people think (No matter what every other Air Force thought - my own note)) had no advantage over the .303" from directly behind the Fw190 (Fighter Command's chief worry.) To make the .5" effective, the pilot needed to use a 5degree deflection shot, at the very least, and, as with the bomber turret, four faster-firing guns had more chance of killing the pilot than two. The same thing applied though; once the gyro gunsight was available for fighters, the .5" made more sense. Eventually, in 1943-onwards, the Spitfire XIV was available, with more internal fuel, plus the ability to carry droptanks, and, once the Allies were in Europe, distances weren't critical any more; it's also worth remembering that, with most bombing done at night, Bomber Command didn't need escorts before 1944, when more daylight raids began to happen. *

The K-14 type gyro/computing gunsight, while making the pilot/airframe system more capable, did not enhance the lethality of the .50 for fighters. Your agument that '50's had no gain in killing power based on rubbish like speculation that a "50 seemed likely to 'skid' off the rear fuselage" is another statement with no basis in fact - especially when dealing with .032/.040 aluminum sheet. 

While American pilots would occasionally speculate on improving a battery by adding 20mm, nobody was clamoring for .30 caliber based on having more guns or more ammo or faster firing but lighter caliber.

There is a reason that most countries in Africa mandate that a .400 caliber of above is the minimum rifle caliber to be used on any of the Big Five - the primary reason is MUCH higher probability of a killing shot placed correctly on an animal like a Cape Buffalo or Elephant from a rear quartering deflection shot - to actually penetrate to the heart or brain - than a lighter and even faster bullet. 

A casual review by you on a variety of USAAF gun camera film from six o'clock should reveal to you the structural debris in the target's wake, including wings, elevators, cowling covers, etc. 

I'm happy to get off the 'white charger' - would love to see you trot out the facts behind the comparisons you quote - and see if the basis of any such documents reflect the state of the art in .50 caliber HMG and AP/API ammo in 1942. It would be equally amusing to see the rationale for LW discarding 7.92mm and replacing with 13mm and 20mm weapons as standard - ditto the Finns, VVs, IJN, etc, etc.,


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## Dcazz7606 (Feb 6, 2012)

Regarding the P-38 Lightning, while it had a number of vices like compressability issues, heating to name a couple. I think the biggest achilles heal was the WPB and the politics involved in making progress for a complicated fighter. The inability of getting a 2nd production source approved until it converted the vega plant in 1945 and the gov'ts refusal to accept delays forced the USAAF to accept the plane with it's flaws. A second source would have allowed the continued production of the plane while a new model (example P-38 K or Merlin and maybe Griffin powered versions) could be produced without interuption. According to Warren Bodie, the K could have been introduced easily but it would not accept delays after being forced to take deliveries with the H model because the new engine "egg" was not ready and eventually introduced on the J. 
The politics of the drop tanks also doomed many bomber crews to being killed or interned as Lockheeds Milo Burcham demonstrated on August 27th, 1942 a 3200 mile ferry range with the 300 gallon tanks on a P-38F. The bombers could have had capable escorts from the begining had there been more practicle thinking in government.


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## Shortround6 (Feb 6, 2012)

Dcazz7606 said:


> Regarding the P-38 Lightning, .........
> The politics of the drop tanks also doomed many bomber crews to being killed or interned as Lockheeds Milo Burcham demonstrated on August 27th, 1942 a 3200 mile ferry range with the 300 gallon tanks on a P-38F. The bombers could have had capable escorts from the begining had there been more practicle thinking in government.



Do not confuse ferry range with operational radius. Operational radius is the distance the plane can fly AFTER dropping the tanks AND engaging in COMBAT for XX number of minutes. Even if the P-38 could carry the 300 gallon tanks on a real mission they might mean it could go in further than it could get out. The advent of the "J" with 410 gallons internal fuel instead of 300 went a long way in extending the operational radius.


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## Glider (Feb 6, 2012)

Edgar Brooks said:


> Oh, please, do get down from your white-charger-riding-to-the-rescue-of-the-wagon-train, and try reading what was said. The RAF/Air Ministry said that, until the GGS arrived, the .5" gave no advantage over the (already in use) .303". Nowhere have I seen the word "puny" used, nor is it implied, so stop putting words into the mouths of the inspection teams.
> The .5" gave no extra hitting power because the average RAF pilot couldn't master deflection shooting past a few degrees, and both the .5" AND the .303" both seemed likely to skid off the rear fuselage, at low angles, so what was the point of adding extra weight (one .5" + ammunition weighed more than two faster-firing .303" + their ammunition) for no gain in killing power?
> Once the GGS came available, the Air Ministry went straight into fitting the .5" into converted airframes, so they certainly had no prejuduce against the weapon, as a weapon.



Thre is no way that the 0.5 would skid off the rear fuselage and I seriously doubt that a 303 would skid off either. I have read a number of the official reports on the effectiveness of the allied guns and they do mention that the 0.303 has a good chance of tumbling after entering the fuselage which basically ruins their penetration. I have read that the 0.5 wouldn't penetrate the pilots armour of an Me109 due to the angle of the seat but its worth remembering that the firing aircraft wasn't always directly behind so the angle would change and the penetration differ.
I have read the file that deals with the chances of shooting down an me109F with the 303 and IIRC the chances were about 3% of the bullets that hit the aircraft would cause fatal damage.

Also of course the 0.5 is almost certain to do serious damage to the other parts of the aircraft.

Can I ask which file the details you quaote are in at the NA as I expect to go their next week and it looks like an interesting file.

As for the theory that the GGS was a dependency for the installation of the 0.5 I find that difficult to believe. Production of the GGS was far outstripped by the production of E wing Spitfires. 

Also the theory that the RAF couldn't hit with a few exceptions anything apart from dead behind. I would say that the RAF found it as difficult as anyone and from around Aug 1944 on were better than most (without the GGS) as our training was the better than anyone else. The GGS improved everyones shooting no matter what they flew and the main aim was to get the 20mm on target.

Finally the statement on the convergence of a bombers guns lacks logic. The guns were so close together, it would make damn all difference if they converged at 50 or 250 yards.

PS thanks for your comments on the rear fuel tank in the Spit. 
The document I have was prepared by the Air Ministry who wanted information on the long range fighter capabilities of the RAF. Details are given for the Spit IX clean, with the rear tank (both original and cut away fuselage) and with 45 and 90 gallon drop tanks. From this I believe that these options are available to the RAF should they need them.
It also gives details of the Tempest V with and without additional internal tanks and with 90 or 180 gallons in drop tanks. 

Either way if you could let me know where I could find the file of the firing trials against the Fw 190 it would be appreciated


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## Readie (Feb 6, 2012)

On the BBC Bomber Boys programme last night ( see my separate thread) that had a live demo of a .303 hitting the same thickness steel as a LW Focke Wulf armour protecting the pilot. It nearly penetrated...very nearly, but not quite.
John


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## Airframes (Feb 6, 2012)

Two rounds of .303 were fired, one ball and one AP, from a Bren. The ball was ineffective, and the AP almost fully penetrated, causing a little bullet splash. Both of these shots were fired at around 100 yards, just going off the camera angle.


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## Readie (Feb 6, 2012)

Airframes said:


> Two rounds of .303 were fired, one ball and one AP, from a Bren. The ball was ineffective, and the AP almost fully penetrated, causing a little bullet splash. Both of these shots were fired at around 100 yards, just going off the camera angle.




I was amazed at the hitting power of a .303. That was b' thick steel !!


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## MikeGazdik (Feb 6, 2012)

The British .303, the Russian 7.62x54R, the German 8mm , and American 30-06 are all very similar in power and performance. A couple have a little more energy, but really pretty close to each other.

The .50 caliber round for a Browning is a different beast!! .50 cal M2 ball = 720 grain bullet, 2,800 fps, *12,600 *lbs ft of muzzle energy! .303= 150 grain bullet, 2,723 fps, *2,470* lbs ft of muzzle energy.

Thats a 10,000 pound difference in muzzle energy. IF .303 almost made it through armor plate, I think an extra 10 grand of energy should do the trick.


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## drgondog (Feb 6, 2012)

John - Imagine a .50 cal API in comparison with ~ 4x KE of the .303/30-06 on that armor in that test. 

I have personally shot a Barrett 50 at 100 yards with just 50 cal commercially available 647 gr FMJ Ball ammo and it easily pentrates four 1/4" plates (4130 steel) approximately 4 inches apart. I have not fired the 696 gr AP but it should easily outperform the 647 gr Ball ammo. The above results are against steel but not armor plate hardened- 

I have not fired but have witnessed similar performance with a Barrett shooting through a V-8 engine block at 'off angle' (maybe 45 degrees) which punches through completely, including car body steel skin, on both sides.

Thinking about 30-06 or .303 in 150gr or 180gr FMJ Ball in the same tests makes me giggle regarding the comparison. 

Having said this I don't recall offhand what the standard .303API round was comprised of, nor do I recall the exact muzzle velocity - But I recall the Brit Browning 1919 was manufactured by Vickers, had a cyclic rate of 1100-1150 rpm, and IIRC had a MV of 2500fps w/174gr .303. Did Bomber Command use 150 or 174 gr Mk8?

The Browning AN/M2 by comparison with the M33 FMJ Ball 706gr ammo will penetrate 3/4" hardened steel plate and the lighter M8API ----> 7/8" at 100 yards with 622gr API. MV for the M33 is 2900 fps 
What is noticable is the flight path deviation as the round punches through each plate.


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## Shortround6 (Feb 6, 2012)

According to Tony Williams the use of ball ammo declined as the war went on with two the Spitfires .303 guns firing all AP and the other two firing all incendiary by the late part of the war.


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## Readie (Feb 6, 2012)

A .50 is clearly the more powerful weapon.Then again a cannon is even more powerfull. 
The point in 'Bomber Boys' was seeing the enemy, firing in time and actually hitting it was very very hard. Deflection practice for air gunners was done with pigeon clays and shotguns. Looking at the tail end charlie turret I'm amazed that anyone could be so cramped, cold and scared and still function as an effective gunner.
One reason for the British sticking with the .303 was the multi gun aspect...would having more .303 barrels be better, and give a greater chance of scoring a hit than fewer .50 ones?
John


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## Messy1 (Feb 6, 2012)

What would the weight difference amount too between the comparable ammunition rounds carried for each plane? .50" vs.303". That maybe the deciding factor why the .50" was not used, along with the additional weight of each .50" caliber gun vs. a .303" gun.


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## bobbysocks (Feb 6, 2012)

you are going to be able to carry 4 or 5 time more 30 cal than .5. but as for the more ammo is better theory....i would like to see the report on that. seems like you are hoping more for a lucky shot ( or an unlucky adversary) rather than the skill of your gunner. usaaf had 30 cal mgs....1919 brownings. why not give the waist gunners a dual 30 or quad 30 set up? you would throw more lead but would you bring any more of the enemy down? i am only speculating it was knock out punch they were going for. they didnt want to do a little damage but put a serious hurting on whatever they were shooting at. i have and have shot 30 cal AP. back in the 80s the one surplus store i bought ammo from ran out of regular 30-06 ammo and game me a deal on AP. we went to the range and shot at the T-1 hardened steel targets. the ball bounced off but the AP went through it like butter. I can only imagine what 50 cal API would can do. i suspect politics had more to do with this than anything else. like when the US military went from the garand to the M1a...and from that to the M16. there was a lot of stalling due to politcal bias and ( pay offs??? ). if the 8 303s in a spit were that successful....dont you think everyone else would have followed suit?


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## drgondog (Feb 6, 2012)

Messy1 said:


> What would the weight difference amount too between the comparable ammunition rounds carried for each plane? .50" vs.303". That maybe the deciding factor why the .50" was not used, along with the additional weight of each .50" caliber gun vs. a .303" gun.



my point about ammo weight differential on a Lancaster between 2x.50 cal per turret versus 4x.50 gan - in context of gun and ammo weight - is trivial when compared to the overall usefull bomb load.

As I am reading it seems that an influential officer in RAF championed quad 303's and crafted interesting reasons to keep them. The difficulty in this dialogue has been to separate factual points of argument versus opinions.

My OPINION is that a .50 Cal AN/M2 is one hell of a lot better air to air weapon than two Browning Mk II (1919 AN w/.303).

One poster's Opinion is that the RAF officer(s) had a rational argument opposed to Leigh-Mallory and, further, he believes that a .303 and a .50 are more or less equal in killing power at low deflection angles - therefore the choice of .303 for defensive armament was sound 

The Facts are that the 50 Cal API was 400fps faster, had a bullet mass 639/174 ratio, had a much longer effective range, had nearly five times the Kinetic Energy (with above ratios) at the Muzzle and got better further out.

The Facts are that every major Air Force and Navy discarded 7.72, 7.7 and 7.92mm weapons in favor of larger caliber wepons of .50 caliber or larger, while the RAF labored onward with .303 defensive armament, and in many cases as standard fighter armament.

The Facts are that USAAF fighters in combat with LW fighters seemed to have no trouble shooting down LW fighters from zero angle deflection from the rear, and in many cases did so with only one .50 caliber still firing.

Leaving one to question the Opinion that .twice as many .303's are better than the results that could have been achieved if RAF had replaced them with the .50 caliber for defensive (or offensive) purposes.

It should be obvious that RAF DID replace all .303 weapons with .50 Cal or better and never reversed that decision.

One may then form an opinion that the winning Opinion that selected the .303 in lieu of the .50 was either ill informed or the opinion to later discard the .303 with the .50 and/20mm was foolish.

What is your Opinion?


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## Shortround6 (Feb 6, 2012)

We have gone over this before. In making a comparison between the two calibers, you not only have to take into account the guns and ammo ( and weight of each, belted .50 cal can weigh 5 times what belted .303 weighs per hundred) but what year ( the .50 changed rates of fire in 1940 and in 1945) and what ammo or mix is being used in each caliber.


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## drgondog (Feb 6, 2012)

agreed for a payload discussion


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## Glider (Feb 6, 2012)

One further point is that the RAF were very keen to swith from quad 303 to twin 0.5. The problem was that the turrets had to fit the current aircraft and the weight increase had to be reduced. Some Lancs had a twin 0.50 in the dorsal position (as the one at Duxford) and some Lancs and Halifax's had twin 0.5 in the tail. Indeed some of these had a built in radar direction capability making them possibly the most advanced turret of WW2.


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## Juha (Feb 6, 2012)

Hello
one British test report with info on .303, .5 and 20mm, found by Kurfürst, can be seen here http://www.ww2aircraft.net/forum/aviation/best-armed-fighter-15964-14.html message #199.

IIRC the .5 B. Mk. II incendiary ammo is the older design, not US Mk. 8, which IIRC was a copy of Soviet 12,7mm AP/I.

Juha


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## davparlr (Feb 6, 2012)

renrich said:


> The 50 BMG "skidding off" of aircraft fuselages??? Now I admit that this was 1960 and maybe the projectile was different. I believe that our ammo was just normal ball (full metal jacketed) and I fired the new M60(7.62 Nato, comparable to the 303 British) and the 50 BMG at old vehicles on the range at Fort Hood. The difference in the two rounds was spectacular. On old half tracks and 2.5 ton trucks the 50 tears big gaping holes and will go all the way the body work from one side to the other. No way a WW 2 AC has heavier body skin than a truck.


 
I will say I just shook my head at that statement. It is hard to imagine a .50 cal skidding off the thin aluminum skin of a fighter everywhere except maybe an almost parallel hit or at long range. But I am not a ballistics expert.


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## Shortround6 (Feb 6, 2012)

drgondog said:


> agreed for a payload discussion



I am certainly not trying to say that a .303 round is equal to a .50 cal round, they aren't. 
I am certainly not trying to say that a .303 machine gun is equal to a .50 cal machine gun, they aren't.

However two .303 guns will put out just under 3 times the bullets that a single .50 cal will which closes up the striking power of the quad .303 armament vs a twin .50 armament, either wing or turret. Please note that this is for 1940 and later .50 cal guns. In the BoB the .50s probably would have been the 600rpm guns and not the 800rpm guns so the .50s advantage in weight of fire or energy all but disappears. 

Just as the Mix of ammo for the .303 changed with the years with better ammo being much more available in later years so did the ammo for the .50 cal evolve and change. Any test results, to be seriously considered at this date, would have to have the test date and types of ammo being tested. While the testers at the time knew what they were testing, "quoting" a test without giving a date or ammo used does little more than confuse the issue at this point (70 years later). 

.303 "Ball" used a lead core and a soft/light tip inside the jacket. Penetration of certain items/targets may very well be dismal due to mushrooming of the point or tipping of the projectile. 
.303 AP will do much better but still is a _NOT_ a competitor to the .50 cal ball round let alone the .50 cal AP. 
There were two different .303 incendiary rounds in use. the MK IV which was a incendiary tracer which burned all the way to the target and the MK VI which ignited on impact and carried .5 gram of incendiary compound and was judged twice as effective as the MK IV. the American MK 8 .50cal API carried about 1 gram of incendiary material and carried it in the nose in front of the AP core. It was sort of an either/or round. It might set fire to unprotected things or it would penetrate armor. The incendiary compound was not likely to penetrate the armor, being stripped away and ignited as the core punched through. The .303 incendiary wasn't going to penetrate much either. 
Late war fighter ammo for the .303 was pretty much two guns loaded with AP and two guns loaded with the MK VI incendiary. 
Please note that a .303 Browning firing MK VI ammo at 1140rpm will deliver 9.5 grams of incendiary material per second. A .50 cal Browning will deliver about 11-13 grams if firing 100% MK 8 API. before 1943/44 the .50 will being firing a mixed belt of ball, AP and Incendiary. 
Primary difference between .50 ball and early .50 AP was that while the steel core of the ball was soft steel ( there was only a little bit of lead in a .50 ball round) the core of the AP was hardened. 

The advantage still is with the .50 cal gun but the overall difference tends shrink and grow with the year and ammo availability.


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## Dcazz7606 (Feb 6, 2012)

Shortround6 said:


> Do not confuse ferry range with operational radius. Operational radius is the distance the plane can fly AFTER dropping the tanks AND engaging in COMBAT for XX number of minutes. Even if the P-38 could carry the 300 gallon tanks on a real mission they might mean it could go in further than it could get out. The advent of the "J" with 410 gallons internal fuel instead of 300 went a long way in extending the operational radius.


 
Range and radius differences are understood. The point was made to underscore the bureaucratic war on the home front. I've read Gen. Monk hunter also hated the P-38 and did little to get them combat ready before the planes were sent to Africa for Torch. He loved the P-47 even though the range was too short to do the job properly.


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## drgondog (Feb 7, 2012)

Shortround - I agree Everything you noted in your post above when the conversation leads to throw weight. If we bring the discussion to defeat of armor or 'kill capability' and conclude that the .303 twin guns to the date of the report being cussed and discussed are 'about equal' to the AN/M2 .50 cal, we should be comparing the .303 rate and ammunition capability with the AN/M2 and API vs API, or AP vs AP respectively - at approximately 1100 fps and 800 fps with an advantage in MV to the AN/M2 suite of ammunition.


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## drgondog (Feb 7, 2012)

Juha said:


> Hello
> one British test report with info on .303, .5 and 20mm, found by Kurfürst, can be seen here http://www.ww2aircraft.net/forum/aviation/best-armed-fighter-15964-14.html message #199.
> 
> IIRC the .5 B. Mk. II incendiary ammo is the older design, not US Mk. 8, which IIRC was a copy of Soviet 12,7mm AP/I.
> ...



Thanks for finding the link Juha. Interesting summary on the tests ~ 30% penetrate the 109 armor of ~ 22mm/.8 inches of laminates duraluminum when a.) above the full fuel tank from 5 degrees deflection at 200 yards, or b) through fuselage, fuel tank and back armor when not impeded by fuel.

and ".303 completely ineffective" when compared to the .50 in the same tests.


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## renrich (Feb 7, 2012)

As stated in Lundstrom, the Zeke had two 7.7 MM MGs firing through the engine cowling. The pilots of the Wildcats found that if the Zeke was out of 20 MM ammo they were relatively safe as long as the Zeke was on their tail. The 7.7 ( similar to the 303) just could not do enough damage to disable or kill the pilot of the Wildcat. It was called the "pin cushion" tactic. The Japanese changed those 7.7s later to 12.7s.

Besides muzzle energy the 50 BMG had a much superior ballistic coefficient and sectional density to the 30 cal which translates to much better downrange velocity, flatter trajectory and better penetration.

I do suspect that the 8-303s in the Brit fighters during the early going( through the BOB) may have been as good a choice as any because: the 50 BMG s were not available and until the RAF had the time to spend on gunnery training most of the pilots were not good enough gunners to take advantage of the lethality of the 50 BMG.


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## Tante Ju (Feb 7, 2012)

renrich said:


> Besides muzzle energy the 50 BMG had a much superior ballistic coefficient and sectional density to the 30 cal which translates to much better downrange velocity, flatter trajectory and better penetration.



I do not think it is issue with aircraft board gun - these fire 2-300 meter maximum.. long range performance is interest of sniper rifle, and anti material machinegun, for which 50 BMG was original designed.. hence weight was less an issue, but I doubt in aircraft configuration, better ballistic was as noteworthy as greater bulk a disadvantage..


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## Readie (Feb 7, 2012)

renrich said:


> I do suspect that the 8-303s in the Brit fighters during the early going( through the BOB) may have been as good a choice as any because: the 50 BMG s were not available and until the RAF had the time to spend on gunnery training most of the pilots were not good enough gunners to take advantage of the lethality of the 50 BMG.




The RAF had pilots who were crack shots (Stanford Tuck) and the vectoring of the 8x .303's proved good enough in the BoB. 
That's not to say that having 8 x .50 would be better or 4 x 20mm cannons or a mix of .50 and 20mm. Whatever.
The RAF had what it had in the early WW2 years and pilots adapted.
We didn't do a bad job with the .303 eh...
John


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## renrich (Feb 7, 2012)

Tante Ju, you are misinformed. The USN during a full deflection gunnery run opened fire at around 1000 feet. Many times pilots would fire at ranges longer than that. However, at 300 yards the much superior ballistic properties of the 50 BMG over the 303 or US 30 cal paid off as the BC of the 50 BMG enabled it to arrive at the target sooner going faster and that higher velocity plus the much better SD gave the projectile more penetration. When the target is going 300 mph at almost right angles to the attacker a split second can make the difference between hits in the cockpit area or engine compartment versus further back on the aft fuselage.

Obviously the RAF had good gunners among their pilots but the fact is that many of the pilots in the BOB barely had any time at all in a fighter and their gunnery skills must not have been very much to write home about, through no fault of their own. Actually though, I believe on average the most effective fighter pilots in the BOB on both sides were the Poles.

I would wager that if the USN and Marine pilots of 1940 were flying the Hurricanes and Spitfires they would have opted for 4-50 BMGs rather than eight puny 303s.


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## Readie (Feb 7, 2012)

renrich said:


> I would wager that if the USN and Marine pilots of 1940 were flying the Hurricanes and Spitfires they would have opted for 4-50 BMGs rather than eight puny 303s.



With the greatest respect to your countrymen renrich. They had zero combat experience in 1940. The Poles, French British / Commonwealth volunteers had had a vertical learning curve in those early months of WW2.
Experience counts for more than a difference in firepower....
John


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## pbfoot (Feb 7, 2012)

renrich said:


> Tante Ju, you are misinformed. The USN during a full deflection gunnery run opened fire at around 1000 feet. Many times pilots would fire at ranges longer than that. However, at 300 yards the much superior ballistic properties of the 50 BMG over the 303 or US 30 cal paid off as the BC of the 50 BMG enabled it to arrive at the target sooner going faster and that higher velocity plus the much better SD gave the projectile more penetration. When the target is going 300 mph at almost right angles to the attacker a split second can make the difference between hits in the cockpit area or engine compartment versus further back on the aft fuselage.
> 
> Obviously the RAF had good gunners among their pilots but the fact is that many of the pilots in the BOB barely had any time at all in a fighter and their gunnery skills must not have been very much to write home about, through no fault of their own. Actually though, I believe on average the most effective fighter pilots in the BOB on both sides were the Poles.
> 
> I would wager that if the USN and Marine pilots of 1940 were flying the Hurricanes and Spitfires they would have opted for 4-50 BMGs rather than eight puny 303s.


You've got one statement from some guy named Linwell or something but nothing else to back it up


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## pinsog (Feb 7, 2012)

I see "throw weight per second" of a battery of either machine guns, cannon, or both, thrown around on this forum alot. I would like to suggest that total "throw weight per second" isnt the end-all be-all of aircraft armament. Saying that 3 or 4 .303 rounds are equal to 1 .50 round because they weigh the same is ignoring how much power the large individual round has. 
For instance:
1. Would you rather shoot a Tiger tank in the side from 100 yards with 17 pounds of .303, 17 pounds of .50, or a 17 pounder antitank gun? 
2. Would you rather shoot an elephant in the forehead with one ounce, 435 grains, of #9 birdshot from a 20 gauge shotgun, or a 400 grain slug from a .416 Rigby?

I would suggest that "throw weight per second" doesn't mean a whole lot unless the caliber of the weapons is very close.


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## renrich (Feb 7, 2012)

Both in Linnekin "80 Knots to Mach Two" and Lundstrom, "The First Team" is described in detail the overhead, high side, flat side and low side, full deflection gunnery runs the USN used in 1940 through 1945-47 when Linnekin was going through training. Linnekin is a retired USN Captain, graduate of the USNA with the class of 1944, a graduate of the USN Test Pilot School and has a degree in aeronautical engineering. Lundstrom is a highly acclaimed historian who has specialised on the Pacific War.

From Lundstrom, page 452, "In terms of actual flying hours the the Navy's aviation program in the mid 1930s probably offered the the most comprehensive training schedule of all the world's air forces." " The 1935 syllabus, for example, outlined a one year course involving 465 hours of ground school and 300 flight hours."

In 1939 the new syllabus specified , because of the enormous expansion of naval flight training, 26 weeks of flight school and 207 flight hours. The pilots practised fixed and free gunnery during their training but once they were awarded their wings they went to The Advanced Carrier Training Groups for more flying hours, approx. 70 to 150 flight hours which included some gunnery. Once assigned to a duty squadron they had to refine gunnery skills and learned practical tactics. 

If one is ignorant of the writings of these authors which describe exactly the same kind of gunnery skills which were taught the USN and Marine pilots prior to and during and after WW2 then I suggest that you read up and judge for yourself how legitimate the information is. The facts are that the USN trained pilots with little or no combat experience prior to the war went out to the Pacific in a fighter judged inferior to the Zeke and more than held their own. The record suggests that other Allied fighter pilots during the same period, against the well trained IJN pilots did not do nearly as well. "You can lead a horse to water but you can't make him drink."


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## pbfoot (Feb 7, 2012)

Sounds like you seern Field of Dreams far to often "if you build it they will come " I have high regard for the "cactus Aie Force" and they did a magnificent job and do not dispute the valour shown by those men but do not believe for a moment that they were anymore capable then any other Air Power during the same period save the USSR which I admit knowing little about . None of the local libraries carry either of these books and I have no intention of buying them but as I realize that these books are your bible and no doubt a little biased just as books up here are biased , I refuse to believe that the country that produced 5 of the top 10 allied pilots during WW1 would have so quickly forgotten about aerial gunnery .


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## Juha (Feb 7, 2012)

IMHO Lundstrom's First Team books are excellent. I own a copy of Linnekin's book but I haven't have time to read it yet.

Juha


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## pinsog (Feb 7, 2012)

I refuse to believe that the country that produced 5 of the top 10 allied pilots during WW1 would have so quickly forgotten about aerial gunnery .[/QUOTE]

Why would that suprise you? It was 20+ years since WW1 and there had been a great depression so all of Europe including Britain was broke. By the time of the Berlin airlift, the greatest manufacturing entity the world had ever seen, the United States, had exactly 16 tanks in all of Europe. When the Korean war broke out, the U.S. army was reclaiming tanks used for decoration in front of schools and sending them to be rebuilt then shipped to Korea. We had completely disarmed in less than 5 years.


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## Glider (Feb 7, 2012)

If you want to compare the RAF training with the USAAF training the following may be of interest
http://www.ww2aircraft.net/forum/aviation/raf-pilot-training-ww2-26347.html

As for USN WW2 training it as in four stages

College 35 hours to weed out those who would never make it

Primary 11 - 14 weeks on Stearmans 90 - 100 hours

Intermediate 14 - 18 weeks on Texans 160 hours

They were then commisioned and moved to 

OTU 8 weeks on a combat type 100 hours 

It shold be noted that gunnery was limited in this period as they had to deck qualify and that takes time and flight hours. This may seem harsh but its the nature of carrier combat that there was normally plenty of time in the squadrons before combat was reached. Naval warefare consists of a lot of waiting followed by short bursts of activity. It was very rare for a newly qualified pilot would be posted straight to combat.


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## bobbysocks (Feb 7, 2012)

pinsog said:


> I see "throw weight per second" of a battery of either machine guns, cannon, or both, thrown around on this forum alot. I would like to suggest that total "throw weight per second" isnt the end-all be-all of aircraft armament. Saying that 3 or 4 .303 rounds are equal to 1 .50 round because they weigh the same is ignoring how much power the large individual round has.
> For instance:
> 1. Would you rather shoot a Tiger tank in the side from 100 yards with 17 pounds of .303, 17 pounds of .50, or a 17 pounder antitank gun?
> 2. Would you rather shoot an elephant in the forehead with one ounce, 435 grains, of #9 birdshot from a 20 gauge shotgun, or a 400 grain slug from a .416 Rigby?
> ...



i agree with that wholeheartedly. it doesnt matter how much lead you spray if its not going to do much when it gets there. the larger .5 and 20mm had way better range...and if like in the case of the 109 where it was a straight line shot could be brought to bear on longer range targets. haveheard the story about an allied pilot who thought he out ran a couple 109s....just as he was feeling good about things he plane got shreaded by cannon fire. 

i am not saying the 303 was a POS....the uk was very successful with it during the BoB and early part of the war. it was what they had and what they had to play with. they were plentyful in units, parts, and men qualified to service them. but we are comparing apples to bowling balls here....a debate between brit 303 vs us 30-06 is way different from either of those 2 rounds vs a 50 cal...and you would get the same answers.

they went from stearmans to AT6s without a jump to a something like a bt13? that's interesting. what was there training for advanced fighter training?


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## pbfoot (Feb 7, 2012)

Advanced fighter trainer was Hurricane for BCATP


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## slaterat (Feb 7, 2012)

The British chose the .303 over the .50 because their pre war testing demonstrated that for the equivalent weight of batteries , the .303 did more damage to an aluminum airframe. In the typical 8x .303 vs 4x .50 argument the .303 battery is putting about 4 times the number of projectiles in the air, thats 4 times as many holes in an airframe and 4 times the chance of a critical hit. The fault in the decision lay in the future introduction of light armour and self sealing tanks in combat aircraft which had the effect of greatly reducing the .303 chance of a critical hit, while the .50 would have a much better chance to defeat such protection. The fault in the selection of the .50 is that for not much increase in weight you can get a 20mm cannon which probably has a greater margin of superiority over the .50 then the .50 has over the .303.

Slaterat


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## Shortround6 (Feb 8, 2012)

renrich said:


> I would wager that if the USN and Marine pilots of 1940 were flying the Hurricanes and Spitfires they would have opted for 4-50 BMGs rather than eight puny 303s.




we have been over this before. I am sure that if those USN and Marine pilots of 1940 had 1942 .50 cal machine guns with 400rpg they would have made that choice. But in 1940 the British would have had the 600rpg version instead of the 800rpg version used by the US in 1942. Loosing 25% of your .50 cal firepower due to the rate of fire difference makes the .303 look not quite so puny. So does cutting the ammo supply back to a near equivalent weight. For the weight of 2800 rounds of .303 (and both the MK I Spit and the MK Hurricane carried less than 2800 rounds) you get about 620 rounds of .50 cal ammo or about 155 rounds per gun of .50 cal. The other aspect of the .50 cal firepower is which ammo would the British have had for the Bob. When did the US adopt the M2 ball? The M1 ball .50 cal ammo had a muzzle velocity several hundred fps lower than the M2 ball ( in fact 2500fps instead of 2900fps but it did use a slightly heavier bullet for a muzzle energy of 10,765ft lbs instead of the 13,000 or so ft/lb of the later .50 cal ammo). Please remember that a MK III Merlin only had 880hp for take-off if operated by the book and not using the 12lb of combat boost. Normal climb was restricted to 2600rpm and not 3000rpm. Adding several hundred pounds of guns and ammo would have improves the firepower of both British fighters but it also would have reduced flight performance. 
This changed very quickly as both the MK II Spitfire with the Merlin XII engine and the Hurricane II with the Merlin XX started production during the BoB but the vast majority of the British fighters that fought had the older version engine. 

Those USN and Marine pilots of 1940 would have had to choose between the eight puny 303s and four .50 cal guns that fired 25% slower, had about 20% less striking energy per bullet, had a very little difference in flight time to the .303 at practical air to air ranges and had 1/3-1/2 the ammo supply of the 4 gun .50 cal fighters that the US used in 1942.

The whole .50 cal vs .303 thing in the BoB is a red herring. By 1943/44 the situation had changed drastically and the continued use of the .303 is a lot harder (nearly impossible?) to explain.


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## nuuumannn (Feb 8, 2012)

> The whole .50 cal vs .303 thing in the BoB is a red herring. By 1943/44 the situation had changed drastically and the continued use of the .303 is a lot harder (nearly impossible?) to explain.



Amen to that. It would be interesting to find how the British came up with the conclusion they did in the paperwork Edgar posted. If British heavy bombers were fitted with .50s rather than .303s, I sure that gunners would have at least felt more confident about attacking the enemy. I was aware that it was pilots who told gunners not to fire on night fighters for fear of giving their position away and not an official source; the RAF weren't that stupid. As well as Leigh-Mallory, Harris was also a strong advocate for arming the bombers with .50s.

An aside; Leigh-Mallory and his brother both died on mountain sides; his older brother George Mallory died ascending Everest in 1924, while Trafford Leigh-Mallory (their father's middle name was Leigh and he later changed his sirname to Leigh-Mallory) died when his Avro York, loaded with his family and belongings on a flight to Ceylon crashed into a mountain side in the French Alps in bad weather in November 1944. In true Leigh-Mallory style, his aircrew had advised against flying in such miserable conditions, but he stubbornly insisted on going, so bringing about his and his family's death. He was on his way to become C in C RAF South East Asia Command. His replacement was Battle of Britain rival, New Zealander Keith Park.


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## Readie (Feb 8, 2012)

Shortround6 said:


> The whole .50 cal vs .303 thing in the BoB is a red herring




Precisely. Its another 'what if'....
As you say things changed quickly as WW2 progressed but, in the BoB we had what we had .303's.

John


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## drgondog (Feb 8, 2012)

Remember this discussion of .303 vs .50 was introduced by a memo dated in 1942 arguing the merits of the .303 over a .50 cal and the reference was 'defeat an FW 190'. It lost focus between discussions of more chances for a head shot kill with more ammo, to lack of .50 cal capability at zero deflection, to discussions regarding impregnable frontal armor of the FW 190.

Edgar summarized his opinions as 'littel difference between the two - go with more guns and ammo in the bombers for defense'

BoB wasn't part of the debate. 

No test evidence/data displayed in the RAF report posted by Edgar but Juha delivered the Report Kurfust presented regarding actual RAF tests on .303, .50 cal and 20mm - which clearly demonstrated the capability of .50 Cal AP to penetrate fuselage, bulheads, empty skins on fuel tank and still get 30% probability of penetration of the 22mm of duraluminum Me 109 seat/head protection - whereas the .303 was cited as completely innefective. The 20mm was 100% effective.

It is unclear from the Report that the AN/M2 was used, or US API/AP ammunition.

So to reset - Decision made by RAF to continue using .303 for defensive purposes until two years later (1944) - and we are debating this with fairly clear hindsight both with respect to .303 vs .50 and .50 vs 20mm (or 15mm)


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## pinsog (Feb 8, 2012)

slaterat said:


> The British chose the .303 over the .50 because their pre war testing demonstrated that for the equivalent weight of batteries , the .303 did more damage to an aluminum airframe. In the typical 8x .303 vs 4x .50 argument the .303 battery is putting about 4 times the number of projectiles in the air, thats 4 times as many holes in an airframe and 4 times the chance of a critical hit. The fault in the decision lay in the future introduction of light armour and self sealing tanks in combat aircraft which had the effect of greatly reducing the .303 chance of a critical hit, while the .50 would have a much better chance to defeat such protection. The fault in the selection of the .50 is that for not much increase in weight you can get a 20mm cannon which probably has a greater margin of superiority over the .50 then the .50 has over the .303.
> 
> Slaterat



It continues to amaze me that anyone who has seen a .303 or 30-06 next to a .50 in real life could continue to argue that the .30 was a better choice. Again, I would rather shoot an Elephant 1 time with a 400 grain .416 bullet than shoot him 10 times with a .22 long rifle.

People point to the British saying the ".50 was neither fish nor fowl" when compared to the .303 or 20mm, as if the fact that they made the conscious decision to ignore the .50 in the 1930's was the right one. I maintain that, like America not developing a good supercharger or testing their torpedoes, the British simply screwed up.


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## Readie (Feb 8, 2012)

pinsog said:


> I maintain that, like America not developing a good supercharger or testing their torpedoes, the British simply screwed up.



Either that or economics. We spent our money at RR and Supermarine so. maybe Vickers played second fiddle?
There is another factor, the .303 was the universal British machine gun, tried and tested from 1914 in WW1 and not without a good deal of hitting power in multiple form. Maybe the designers stayed with what they knew?
I'm not defending the .303, just offering an explanation.

John


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## tomo pauk (Feb 8, 2012)

How come that America did not developed a good supercharger???

British might 'screwed up' with .303s for their bombers, but their day/night fighters were 90% cannon-equipped from late 1941 (only Germans carried comparable batteries in the air). Anyway, since the bomber's best policy was not to fire at all, the decision to carry on with LMGs seem like non-issue to me.


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## nuuumannn (Feb 8, 2012)

> and we are debating this with fairly clear hindsight...



I think it is universally agreed that the decision not to fit .50s to British bombers was perhaps not the best. It's why it didn't happen that's got everyone talking.


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## oldcrowcv63 (Feb 8, 2012)

Re .50s vs .30s, I can only offer examples to suggest that armament that enables the pilot and aircraft to get bullets into the target is what really counts. 

- AVG in China and Burma, P-40B, with 2x .50s and 4 wing-mounted .30s with ceiling of 32,400 ft. P-40B did very well vs its IJA opponents. 
- USAAF Pursuit Squadron-17 (with PS-20 reinforcements) flying P-40E in Java with its 'improved' battery of 6 wing-mounted .50s possessed both a degraded ceiling of 29,000' and climb rate and couldn't engage bombers and escorts of IJA IJN aircraft flying at higher altitude. 
- F4F-3 with 4 x wing-mounted .50s and firing time of over half a minute was felt to be adequate to intercept and counter all IJN opponents in whatever numbers they were encountered. ceiling: 35,000+ ft.
- USN pilots were horriifed to find their F4F-4, with its 'improved' 6x.50s (defined and acquired to satisfy the the RN's FAA) climbed with a rate akin to the TBD Devastator. The -4, even with the increased numbers its folding wings allowed, created a more permeable defensive screen to IJN raiders. ceiling: 30,000+ ft and reduced firing time to less than 1/3rd minute. The decreased ammo supply (to save weight and preserve some performance) made the Grumman a poor defender in the face of large raids. Something the FAA typically didn't need to consider.

Those additional HMG, (_heavy_ indeed) came at a significant performance price that sometimes made the difference between victory and defeat; no matter how much greater or more lethal were the actual gun and ammo.

USN pilots finally got what they wanted in the FM-1 which reverted to the 4 gun battery, but by then, the advent of the F6F and F4U had mitigated the problem.


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## davparlr (Feb 8, 2012)

tomo pauk said:


> How come that America did not developed a good supercharger???


 
I can make a guess. The AAF seemed to favor and fund the development of the turbo to provide high altitude performance, and the Navy did not perceive, nor get, a high altitude threat.


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## oldcrowcv63 (Feb 8, 2012)

davparlr said:


> I can make a guess. The AAF seemed to favor and fund the development of the turbo to provide high altitude performance, and the Navy did not perceive, nor get, a high altitude threat.



I think the USN, with its preference for radial engines, was relatively satisfied with the 2-stage superchargers on its P&W 1830-76 and -86 engnes. The turbocharger was in development strictly for USAAF aircraft with Allison built in-lines as I understand it.


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## tyrodtom (Feb 8, 2012)

The decision not to shoot at nightfighters might have been forced on the Bomber Command pilots by their observation that the .303s very seldom downed the NF. Instead it showed the night fighters exactly where they were.


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## Shortround6 (Feb 8, 2012)

pinsog said:


> People point to the British saying the ".50 was neither fish nor fowl" when compared to the .303 or 20mm, as if the fact that they made the conscious decision to ignore the .50 in the 1930's was the right one. I maintain that, like America not developing a good supercharger or testing their torpedoes, the British simply screwed up.



Once again, the .50 that the British tested and ignored in the 1930s was NOT the .50 cal gun and ammo the Americans were using in Dec 1941 and 1942. They tested the older 600rpm gun (if that, it often failed to reach that figure due to belt drag and/or belt lift problems) with the M1 Ball ammo with it's lower muzzle velocity. The gun and ammo weighed about the same as the later gun (which used the same designation) and cartridge. The higher velocity was th result of new powders which allowed a more progressive burn giving more velocity at the same peak pressure. As an example the US 1906 .30 cal cartridge used over 50,000 lbs pressure to drive it's 150 grain bullet at 2700 fps. The later M2 ball round introduced in the 1930s with new powder could drive the same bullet at the same speed with a peak pressure of a bit over 40,000lbs. Vickrs had offered two if not three different .50 cal cartridges to the government during the 20s and 30s of greatly varying performance. The smallest of which went on to be adopted by the Italians and Japanese army.

The supercharger issue is another red herring. In the 1930s the US superchargers were as good ( or as bad) as anybody elses. British superchargers only took the lead when Hooker went to work on them.


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## Shortround6 (Feb 8, 2012)

oldcrowcv63 said:


> I think the USN, with its preference for radial engines, was relatively satisfied with the 2-stage superchargers on its P&W 1830-76 and -86 engnes. The turbocharger was in development strictly for USAAF aircraft with Allison built in-lines as I understand it.



With limited budgets (peace time) it didn't make much sense for both services to fund the same research. General Electric had been working on turbos since WW I. Quite a few Curtiss V-12 engines had turbos installed on them during the 20's and 30's and with the B-17 and B-24 the round engines certainly got a large share of the turbos. P&W had a patent for a two stage supercharger in 1937? At any rate, the P&W two stage supercharged R-1830 showed up at the Army 1939 fighter trials in both a Curtiss Hawk airfram and in a Seversky (modified P-35) airframe. Apparently it wasn't quite ready for service as the few performance numbers that have made it to print don't show much advantage.


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## tomo pauk (Feb 8, 2012)

davparlr said:


> I can make a guess. The AAF seemed to favor and fund the development of the turbo to provide high altitude performance, and the Navy did not perceive, nor get, a high altitude threat.



When one says 'America' and 'supercharger', that would point into both radials inlines, and both Navy and Army AFs, both turbos mech superchargers. With Merlin as the most important exception, what other country/service/manufacturer was providing/operating better superchargers than US planes were equipped with? 
The Navy considered (I'd humbly agree) that engine-driven two-stage engines were show stoppers for high altitude threats.


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## buffnut453 (Feb 8, 2012)

oldcrowcv63 said:


> Those additional HMG, (_heavy_ indeed) came at a significant performance price that sometimes made the difference between victory and defeat; no matter how much greater or more lethal were the actual gun and ammo.



There is one other factor that's being politely ignored in this debate and that's the question of reliability. The RAF's experience with US-provisioned .50 cals wasn't exactly comforting - the Buffalo and P-40 both suffered from frequent gun stoppages, as did the early Mustangs (oh, and the F4F as well!). Those issues were not fully resolved until late 1942 (in the case of the F4F) and even later for the P-51. It's all very well saying, with hindsight, that the .50cal was a better weapon (which, undoubtedly, it did become...eventually) but I think it's folly to suggest that a combat-reliable .50cal weapon installation was available in the late 1930s, or even 1940, such that the RAF, en masse, could have migrated from the venerable .303s. 

By the time we get to 1943 or later, the cost of migrating was so huge, because the RAF had expanded so much, as to make the whole question somewhat moot. Would installing .50s on Bomber Command aircraft really have reduced loss rates significantly when the German nightfighters had cannon? I suspect not.


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## renrich (Feb 8, 2012)

To finish up the Lundstrom and Linnekin issue, Lundstrom is the one making the statements regarding how well trained the USN pilots were especially in full deflection shooting compared to other air forces( including the AAF). Linnekin makes no claims of that nature. They both describe gunnery training that the USN used prior to and during WW2 and in Linnekin's case shortly after the war. That description of gunnery training by the two author's is identical. They describe the different full deflection runs using the same terms and the distances involved are the same. Lundstrom also states that the Navy considered the maximum effective range of the 50 BMG as 400 yards. He also states that the USN began to teach full deflection gunnery in the 1920s. He also states that in a head on attack the pilots would open fire at around 600 yards since the firing time would be so short. He also states that the full deflection gunnery runs were seldom able to be used against a fighter but were applicable to use against a bomber. But the constant practise in full deflection shooting gave the pilots an edge when they were forced to take snap shots against a fighter at high deflection numbers.

Lundstrom's books I have read are meticulously researched so I have no reason to doubt his statements in his books especially when I have seen no credible references quoted by anyone on this forum that dispute his claims.

On the other hand, Linnekin was an active duty career Navy pilot who actually flew those full deflection runs in Hellcats, Bearcats and Corsairs and possibly although he does not mention it specifically in F9Fs which he flew operationally in Korea. I actually have never seen "Field Of Dreams" in it's entirety and don't care to. I am not into dreams but would rather deal with facts. I guess sometimes though it is difficult to change our minds when the facts don't coincide with our perceptions.

For those who have Linnekin's book and Lundstrom's I applaud your good judgment and am confident that your purchase will be worthwhile.


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## fastmongrel (Feb 8, 2012)

oldcrowcv63 said:


> - USN pilots were horriifed to find their F4F-4, with its 'improved' 6x.50s* (defined and acquired to satisfy the the RN's FAA)*


Could we finally put this myth to bed the RN FAA was not the main customer for the -4 and its 6 guns. Does anyone really believe that Grumman would upset its main customer by building aircraft to a much much smaller cutomers specs. Does anyone believe that the USN run by noted anglophobe Adm King would allow the RN to dictate its aircraft specs. The -4 was a USN aircraft they got what they ordered and blaming the RN who possibly asked for 6 guns but would have accepted what they were given is a load of rubbish and smacks of buck passing. The 220 (yes thats all) -4 the British bought werent even the same as the USN version having a different engine and other detail differences.


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## oldcrowcv63 (Feb 8, 2012)

fastmongrel said:


> Could we finally put this myth to bed the RN FAA was not the main customer for the -4 and its 6 guns. Does anyone really believe that Grumman would upset its main customer by building aircraft to a much much smaller cutomers specs. Does anyone believe that the USN run by noted anglophobe Adm King would allow the RN to dictate its aircraft specs. The -4 was a USN aircraft they got what they ordered and blaming the RN who possibly asked for 6 guns but would have accepted what they were given is a load of rubbish and smacks of buck passing. The 220 (yes thats all) -4 the British bought werent even the same as the USN version having a different engine and other detail differences.



Thanks for the contrasting view, Fast. I admit to never hearing it expressed before. Perhaps it's been dealt with in this forum and I just haven't stumbled across it yet. My understanding, perhaps in need of revison, is that Towers, the head of BuAer in 1941, was initially going to produce a lighter, manual wing folding version of its XF4F-4 (with 4 gun armament). However, the RN's FAA insisted on 6 guns per wing for their export model Martlet. He chose to avoid potential production delays of two assemblies by making just the one model that conformed to the RN requirement/request. I blame Towers because he took for granted that the significant British European battle experience was applicable to the lessons his own fleet pilots were learning in their first carrier battles. If he had consulted the pilots I would have less an issue but my understanding is he didn't. British experience in Europe did not translate to that in the Pacific theater and I believe the USN paid a very high price for his decsion. If this is in error, then please advise in what way and please, if you would provide references. I'd very much appreciate it. Thanks.

I don't have any issue with the FAA. I love those guys. they asked for something they wanted because their experience told them it was what they needed. It wasn't our spec, that's all I meant and if I said or implied more, I apologize. 

My impression of King is that, next to British citizens, he hated Americans (at least those in the US army), in fact, I think there is some evidence he disliked everyone except maybe Nimitz and even liked him not so much...


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## Juha (Feb 8, 2012)

One thing I don't understand in this F4F-4 business, why didn't USN pilots just remove the outer .5s. That would not have helped in firing time problem, but they would have gotten lighter plane, even lighter than F4F-4 with 4 HMG and more rpg that they wished. After all the guns were not welded in their places. All what was needed was a bit initiative and disobedience onboard CVs far out on sea.

Juha


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## oldcrowcv63 (Feb 8, 2012)

Juha, GREAT Question and one I've asked myself on occasions too numerous to count.

My only answer is to cite the incredible resistance to any airframe modifications and control exerted by BuAer that persists to the present day, you fly with the configuration they give you, even if it kills you. That's my answer, based on my experience and I'm stickin to it until somebdy tells me it's not true, then I'll dive like dolphin. You have to understand that the USN for all its modern technological bent is one of the most conservative, hide-bound institutions on the planet (next to the politbureau).  

I say this as someone who loves the USN but I am sure I'll catch flack for this post. Oh well. let it come.. 

BuAer told pilots, "if you don't like it and want longer firing time, deselect the two outer guns and keep them for a get-me-home reserve! But BuAer didn't understand then that the 45 seconds or so difference in climbing time to 20,000 feet was important. Many well informed people still don't think it was important to this very day.


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## pinsog (Feb 8, 2012)

Juha said:


> One thing I don't understand in this F4F-4 business, why didn't USN pilots just remove the outer .5s. That would not have helped in firing time problem, but they would have gotten lighter plane, even lighter than F4F-4 with 4 HMG and more rpg that they wished. After all the guns were not welded in their places. All what was needed was a bit initiative and disobedience onboard CVs far out on sea.
> 
> Juha



I have often wondered that about the F4F-4, the P39 in American service, and the P40 in American service. I'm not sure the latter 2 wouldn't have been much better aircraft if they just had 2 synchronized .50's, and of course the P39 with the hub cannon changed to a 20mm and ditch ALL of the wing guns on both of those aircraft.


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## oldcrowcv63 (Feb 8, 2012)

The only in-theater or field modifications I can think of off-hand are those done to the Fifth Air Force B-25, authorized by Kenney in the South Pacific. Not sure if there are any others. I can't think of any done by the USN maybe someone else can recall one.


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## Shortround6 (Feb 8, 2012)

In "America's Hundred Thousand" and in the specification sheets available at Spitfire performance testing including:

http://www.wwiiaircraftperformance.org/f4f/f4f-4-detail-specification.pdf

Show weights and performance with 4 guns and 800 rounds (called _normal_fighter) 4 guns plus bombs and 6 guns with 1440 rounds (called _overload_ fighter). Similar variations in guns and ammo load can be found for other Wildcat models. For USN Brewster Buffaloes and F4U Corsairs. It doesn't seem like the 6 gun fit was mandatory from on high. 

AS far as not listening to their own pilots and listing to the British ???? the timing doesn't look good for this story, they may have listened to the British but with 5 F4F-4 delivered by the end of Dec 1941, the contracts and Specifications had been agreed to well before the USN Pilots had any combat experience with the F4F-3 or F4F-4. First flight of a 4 gun Eastern Aircraft FM-1 was in Aug of 1942. They seem to have gone back to the 4 gun setup rather quickly. When was the 'DECISION" made to go back to four guns? perhaps even before any combat experience from Guadalcanal?


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## Shortround6 (Feb 8, 2012)

pinsog said:


> I have often wondered that about the F4F-4, the P39 in American service, and the P40 in American service. I'm not sure the latter 2 wouldn't have been much better aircraft if they just had 2 synchronized .50's, and of course the P39 with the hub cannon changed to a 20mm and ditch ALL of the wing guns on both of those aircraft.



The P-39 may have been OK ( the Russians flew a lot of theirs that way) the P-40 might have been a very iffy aircraft. The .50 did not take to synchronization very well with rates of fire dropping as low as 450rpm in some British tests.


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## pinsog (Feb 8, 2012)

Shortround6 said:


> The P-39 may have been OK ( the Russians flew a lot of theirs that way) the P-40 might have been a very iffy aircraft. The .50 did not take to synchronization very well with rates of fire dropping as low as 450rpm in some British tests.



Wouldn't a P39 set up with only 2 .50's and a 20mm through the hub been better armed than an ME109 in the BoB? ME109 during BoB had rifle caliber synchronized guns didnt it?


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## Shortround6 (Feb 8, 2012)

pinsog said:


> Wouldn't a P39 set up with only 2 .50's and a 20mm through the hub been better armed than an ME109 in the BoB? ME109 during BoB had rifle caliber synchronized guns didnt it?



Yes the P-39 would have been better armed but then by the time it was in service in any numbers it was a year after the BoB and the standard for fighter armament was moving on. Instead of comparing it to a 109E you should be comparing it to a 109F. 
And then we are back to the two 1000rpm rifle caliber machine guns vs two 500rpm .50 cals (actually the .50s are in better shape as we are comparing them gun for gun rather than 2 RCMG vs a single .50) but the P-40 with only two guns is in rather poor shape firepower wise. Better than an Oscar and few other aircraft but barely passing out an Italian fighter with a pair of of 12.7mm Breda-SAFAT machine guns. 
Compared to a 109F the paired sychro-ed .50s don't really equel the 15mm MG 151 by itself and are well under 1/2 the fire power of the 20mm MG 151.


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## pinsog (Feb 8, 2012)

Shortround6 said:


> Yes the P-39 would have been better armed but then by the time it was in service in any numbers it was a year after the BoB and the standard for fighter armament was moving on. Instead of comparing it to a 109E you should be comparing it to a 109F.
> And then we are back to the two 1000rpm rifle caliber machine guns vs two 500rpm .50 cals (actually the .50s are in better shape as we are comparing them gun for gun rather than 2 RCMG vs a single .50) but the P-40 with only two guns is in rather poor shape firepower wise. Better than an Oscar and few other aircraft but barely passing out an Italian fighter with a pair of of 12.7mm Breda-SAFAT machine guns.
> Compared to a 109F the paired sychro-ed .50s don't really equel the 15mm MG 151 by itself and are well under 1/2 the fire power of the 20mm MG 151.



A P40 with 2 .50's wouldn't be my 1st choice for fighter, and I wouldn't be as concerned about how well the 2 .50's shot down other planes as I would that shedding all that weight might keep ME from getting shot down! I wouldn't want a 2 .50's fighter if I was fighting the Luftwaffe, but I think it might have worked fine against the Japanese.

As far as the P39, shedding 4 .30's and 1000 rounds per gun might have made a BIG difference. Just another "what if" though.


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## Shortround6 (Feb 8, 2012)

pinsog said:


> .As far as the P39, shedding 4 .30's and 1000 rounds per gun might have made a BIG difference. Just another "what if" though.



Not really a "what if" but more of a "who if". Like I said the Russians often operated their P-39s either without the wing guns or with the wing guns taken out.


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## Shortround6 (Feb 8, 2012)

pinsog said:


> A P40 with 2 .50's wouldn't be my 1st choice for fighter, and I wouldn't be as concerned about how well the 2 .50's shot down other planes as I would that shedding all that weight might keep ME from getting shot down! I wouldn't want a 2 .50's fighter if I was fighting the Luftwaffe, but I think it might have worked fine against the Japanese.



You might be better off ditching the .50s and replacing them with .30 guns with 500rpg. Ditching the wing .30s saves 94.4lbs and the ammo weighs another 127.4 lbs. 

swapping the cowl .50s for .30s saves just over 100lbs and the .50cal ammo weighed 228lbs. trading 760 rounds of of .50 cal for 1000 rounds of .30 cal saves another 163lbs. 

Then we can argue if 16-18 rounds per second of .50 cal ammo equals 105-110 rounds per second of .30cal


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## oldcrowcv63 (Feb 9, 2012)

Shortround6 said:


> AS far as not listening to their own pilots and listing to the British ???? the timing doesn't look good for this story, they may have listened to the British but with 5 F4F-4 delivered by the end of Dec 1941, the contracts and Specifications had been agreed to well before the USN Pilots had any combat experience with the F4F-3 or F4F-4. First flight of a 4 gun Eastern Aircraft FM-1 was in Aug of 1942. They seem to have gone back to the 4 gun setup rather quickly. When was the 'DECISION" made to go back to four guns? perhaps even before any combat experience from Guadalcanal?


 
Well, I have to say your time line does look persuasive. Let me try to reconstruct it as reported in Don Linn's Squadron Signal Pub and other sources:
August 1939: Grumman awarded a contract for 54 fixed-wing (G-36) F4F-3 A/C, supercharged P&W 1830-76 with 2 nose .3 in MG and 1 x .5 in. in each wing.
Late 1939: French Purchase 81 G-36A with 4 x .3 in MG Wright Cyclone 1820 engine with 1 stage 2 speed supercharger
January 1940: first production G-36/F4F-3 comes off line. P&W 1830 with 2 stage, 2 speed supercharger begins fleet evaluation.
Early 1940, 3rd production F4F-3 modified armament to 4 x .5 inch HMG with 450 rpg.
Early 1940 Belgium orders 10 G-36As of uncertain specs.
_*Early 1940: Britain orders 100 fixed-wing G36B with a P&W 1830 with 1-stage, 2 speed supercharger with 6 x .5 in MG*_
_*March 1940: USN contracts Grumman to produce a folding wing F4F*_.
_*Spring 1940: Britain changes order for G-36B to be folding wing version (Martlet II)*_
*USN immediately accomodates Britain to avoid production delays and makes XF4F-4 a 6 gun rig, with 240 rpg*
11 May 1940: First G36A flies with 7 produced before France Falls. Britain takes over French Belgium order. 
27 July 1940: first Martlet Mk I is delivered to be upgraded to British requirements (By Blackburn apparently)
August 1940: first 6 Martlet I's arrive in Britain. These A/C become Martlet Mark I.
Late 1940: USN Orders 95 F4F-3A with P&W 1930-90 signgle stage 2 speed Superchargers
25 December 1940: 2 Martlet I's of FAA 804 quadron shoot down a Luftwaffe JU-88 (first US Built A/C to shoot down an axis A/C)
January, 1941: first two squadrons of F4F-3 A/C become operational and commence training cruise deployments.
March thru May 1941: 95 F4F-3A delivered with 30 being set aside for Greece but taken in hand by FAA western Desert squadron.*14 April 1941: XF4F-4 first flight*
Early 1941: USN contracts Grumman for 1,169 F4F-4. at 190 A/C produced per month
October 1941: _Wildcat_ name adopted by USN
November 1941, F4F-4 deliveries begin 
*January 1942: Fleet squadron pilots get their first look at the XF4F-4 during initial Pacific island raids and don't like it.*
Early 1942: Navy Department brings GM to Grumman to transfer production to GM's future Eastern Aircraft Division.
*14 June 1942: BuAer issues order for a 4 gun installation on Eastern's F4F-4 production variant to be known as FM-1. Change to commence with the 11th FM-1 produced. Grumman F4F-4 production was completed unchanged to production end (Early 1943).*
Summer 1942, first folding wing 6 gun Martlet II's delivered to FAA.
August 31:1942 First FM-1 flight 
F4F-4 production ceases in early 1943 with 1169 F4F-4 and 320 Martlet II and IV
Spring 1943: FM-1 first operational deployment
Mid 1943: FM-1 production ceases with 830+ USN 4 gun A/C and 311 FAA Martlet V with 6 guns.

The battle reports on the F4F-4 from Midway, Eastern Sol.and Santa Cruz damned it for performance and firing duration. Prior to those battles, the XF4F-4 was deployed with the shipboard squadrons in the Pacific and considered unsuitable as a replacement for the -3. In response to early complaints, BuAer ordered changes to the 4 gun installation in the upcoming FM-1 in June 1942. The 6 gun Grumman production was retained to supply residual USN and FAA needs until replaced by FM-1s from the Eastern Aircraft plants converted to Wildcat manufacture, with separate USN FAA production lines.

The first production 4 gun FM-1s came off the line in September 1942 but didn't see action until 1943.

There was, according to every source I've seen, no attempt to change the F4F-4 despite the poor reports coming in from the Pacific. There were still many F4F-4s to produce and could be changed in time to make a difference. The FAA was insistent according to the sources but I really don't even know if a proposal to change was submitted to them. I am ready to believe that Towers covered his 6 o'clock with this story. but I don't know.


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## oldcrowcv63 (Feb 9, 2012)

pinsog said:


> A P40 with 2 .50's wouldn't be my 1st choice for fighter, and I wouldn't be as concerned about how well the 2 .50's shot down other planes as I would that shedding all that weight might keep ME from getting shot down! I wouldn't want a 2 .50's fighter if I was fighting the Luftwaffe, but I think it might have worked fine against the Japanese.



The P-40B (with 2 x 0.5 inch and 4 x 0.3 inch guns) flown by the AVG apparently did very well against the Japanese Oscars and readily achieved altitude advantage whereas the USAAF P-40Es with 6 x 0.5 inch guns rarely scored on the Zeros they met over the PI and Java. They couldn't reach the altitude of incoming raids and apparently virtually never achieved altitude advantage over Japanese aircraft. The ceiling reduction with the extra weight amounted to about 3-4,000 feet or more.


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## Glider (Feb 9, 2012)

oldcrow posting 152 was excellent. 
Only one minor amendment and that was the item on the 25th Dec about the Wildcat being the first US built aircraft to shoot down a German aircraft. On the 8th October 1939 a Hudson shot down a German aircraft over Jutland.


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## Juha (Feb 9, 2012)

oldcrowcv63 said:


> The P-40B (with 2 x 0.5 inch and 4 x 0.3 inch guns) flown by the AVG apparently did very well against the Japanese Oscars and readily achieved altitude advantage whereas the USAAF P-40Es with 6 x 0.5 inch guns rarely scored on the Zeros they met over the PI and Java. They couldn't reach the altitude of incoming raids and apparently virtually never achieved altitude advantage over Japanese aircraft. The ceiling reduction with the extra weight amounted to about 3-4,000 feet or more.



One thing to be remember is that AVG had a good air surveillance system, so it usually got timely warning on Japanese raids, so P-40Bs had time to achieve altitude advantage.

Juha


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## oldcrowcv63 (Feb 9, 2012)

Glider said:


> oldcrow posting 152 was excellent.
> Only one minor amendment and that was the item on the 25th Dec about the Wildcat being the first US built aircraft to shoot down a German aircraft. On the 8th October 1939 a Hudson shot down a German aircraft over Jutland.



Thanks Glider, had not heard of that!


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## tomo pauk (Feb 9, 2012)

The 1 20mm cannon + 2 HMGs (with LMGs deleted) for P-39 sounds good to me; the cannon being belt-fed, of course.


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## oldcrowcv63 (Feb 9, 2012)

Juha said:


> One thing to be remember is that AVG had a good air surveillance system, so it usually got timely warning on Japanese raids, so P-40Bs had time to achieve altitude advantage.
> 
> Juha



Very true, but a RADAR based fighter direction system was operational on December 8 in the PI but failed miserably apparently because the ground to air comms were so bad and pilots took matters into their own hands to the detriment of their efforts. 

The Java based early warning and fighter direction system was apparently somewhat similar to that of the AVG, but could only provide about 30 minutes of warning to the interceptors. Reading Bartsch, it appears that time and again, the P-40E's reach their ceiling and watch the bombers fly past above them by about 3,000 feet while the Zero escorts dive down on the USAAF pilots from their perch above the bombers and just tear into them. The P-40E's only survival tactic was to dive away which didn't always work.


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## drgondog (Feb 9, 2012)

There is an 800 pound difference between P-40B and P-40E. 240 pounds difference between 4x30 + 2x50 vs 6x50. installation but only 70 pounds difference in ammo weight. So overall the E weighed about 500 pounds more on Basic weight with ammo added.

The E had 1100 hp allison, the B had 1040.

The B's top speed was achieved at 15K, the E at 12K.

Offhand, except for implied blower impeller setting difference which gave the P-40B its top speed at 15K, 3000 feet higher than the P-40E, is the only rational explanation for the E having better climb to 20K performance. The E should do better to 12K with small weight difference but more power up to 12K.


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## oldcrowcv63 (Feb 9, 2012)

drgondog said:


> There is an 800 pound difference between P-40B and P-40E. 240 pounds difference between 4x30 + 2x50 vs 6x50. installation but only 70 pounds difference in ammo weight. So overall the E weighed about 500 pounds more on Basic weight with ammo added.
> 
> The E had 1100 hp allison, the B had 1040.
> 
> ...



Good stuff, but in the data I've seen it wasn't so much the climb rate that was the problem as the ceiling. The P-40E just couldn't get its ass above 29,000 ft when 'new' and as time on the engine accumulated, that altitude decreased.


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## Milosh (Feb 9, 2012)

These are the service ceiling numbers I have, but it doesn't say if these are loaded or unloaded altitudes.

Mitsubishi G3M "_Nell_" - 33,730'

Mitsubishi G4M "_Betty_" - ~30,000'

Mitsubishi Ki-21 "_Sally_" - 32,800'

Nakajima Ki-49 "_Helen_" - 26,772'

Kawasaki Ki-48 "_Lily_" - 33,135'


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## oldcrowcv63 (Feb 9, 2012)

Milosh said:


> These are the service ceiling numbers I have, but it doesn't say if these are loaded or unloaded altitudes.
> 
> Mitsubishi G3M "_Nell_" - 33,730'
> 
> ...



As I recall, USAAF PS-17 was often scrambled to intercept G3M, G4M and Ki-21 bombers. The figure most often quoted in Bartsch was "3,000 feet above" the P-40Es when they had reached 26-27,000 feet and could coax no higher altitude from their worn out engines.


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## muscogeemike (Feb 9, 2012)

Thorlifter said:


> My favorite is the Corsair. Unfortunately for the purpose of this discussion, the Corsair had no weaknesses! Ha. I guess I would have to say range. It also could do a 4 G inverted negative dive! hahaha.



I would refer you to THE THREADBARE BUZZARD, by Thomas M. Tomlinson. He was from Montana but went to Canada and enlisted in the RAF. After Pear Harbor he joined the USMC and flew Wildcats and Corsairs in the original VMF 214 (pre “Pappy” Boyington). He evaluates both aircraft and addresses their good points and faults. The Corsair, especially the early Corsair (like most early models of all aircraft), did have faults.

He is also critical of the US Navy treatment of the USMC and of Boyington and the later VMF 214.


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## pbfoot (Feb 9, 2012)

muscogeemike said:


> I would refer you to THE THREADBARE BUZZARD, by Thomas M. Tomlinson. He was from Montana but went to Canada and enlisted in the RAF. .


RCAF or RAF he wouldn't be to bright to take that big pay cut


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## MikeGazdik (Feb 10, 2012)

First off, I must confess that I LOVE the P-40B/C. But trying to be objective. I think the success the AVG had compared to other, later, P-40 outfits were: tactics, the aforementioned early warning, and the foe, the AVG was not fighting Zeros.


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## oldcrowcv63 (Feb 10, 2012)

MikeGazdik said:


> First off, I must confess that I LOVE the P-40B/C. But trying to be objective. I think the success the AVG had compared to other, later, P-40 outfits were: tactics, the aforementioned early warning, and the foe, the AVG was not fighting Zeros.



I think that's correct Mike, but of course with a higher ceiling and better climb rate the P-40B/C was able to resort to the succcessful Boom and Zoom tactics Channault promoted. Reading Bartsch, I definitely got the impression the USAAF pilots knew about and wanted to Boom and Zoom but just weren't able to control the circumstances of the engagement, typically surrendering altitude superiority to the Zero. They were very frustrated with the E's inability to climb to intercept altitude, let alone gain altitude superiority. My impression is that the B is fundamentally a better airplane weapon system than the E.


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## Tangopilot89 (Feb 12, 2012)

Carburettors rather than injectors on Spitfire and Hurricane, plus the lack of range (I know some have already mentioned this)

A weakness to the Lancaster and Halifax I think was the lack of belly armament, exploited by night fighters with the fixed upward firing cannon.


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## Maximowitz (Feb 12, 2012)

The Messerschmitt 410 Hornisse. A favourite of mine.

Achilles heels:

Taking off

Flying

Landing


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## A4K (Feb 15, 2012)

McDonnell-Douglas A-4K Skyhawk, one of my all time favourites.

Achilles heel: The New Zealand government.


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## buffnut453 (Feb 15, 2012)

Actually, on reflection it's not that funny...just sad.


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## A4K (Feb 15, 2012)

Exactly mate...


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## bowfin (Feb 15, 2012)

P-38 Lightning: Everybody was scared to dive in it once the compressibility phenomenon reared its ugly head.


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## tomo pauk (Feb 16, 2012)

Everybody?


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## MikeGazdik (Feb 16, 2012)

oldcrowcv63 said:


> I think that's correct Mike, but of course with a higher ceiling and better climb rate the P-40B/C was able to resort to the succcessful Boom and Zoom tactics Channault promoted. Reading Bartsch, I definitely got the impression the USAAF pilots knew about and wanted to Boom and Zoom but just weren't able to control the circumstances of the engagement, typically surrendering altitude superiority to the Zero. They were very frustrated with the E's inability to climb to intercept altitude, let alone gain altitude superiority. My impression is that the B is fundamentally a better airplane weapon system than the E.



What is the difference in climb rate of the P-40B vs the E? I didn't know there was that big of a difference. Yet another reason to like the B/C version of the P-40 even more. Looks wise, the early P-40 is just perfect for me. Nice swept nose, radiator just the right size. The upper fuselage from cocpit back is sweet.


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## tomo pauk (Feb 16, 2012)

deleted


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## Shortround6 (Feb 16, 2012)

It is not just the climb rate but the difference in ceilings, it is not exact but but having a climb rate, say 200ft per minute slower at sea level often means a climb rate 200ft per minute slower at 20,000ft and that is were things get really interesting or really difficult. 

I don't have any figures for the P-40s but some figures for the Spitfire and Hurricane might be interesting. While a look at typical "book" figures doesn't show huge differences, like the Spit I having a service ceiling of 37,400ft to the Hurricane's 34,000ft or time to 25,000ft of 11m 33 s for the Spit and 13m 12s for the Hurricane the actual performance at high altitudes was quite different. the "operational" ceiling (height at which 500FPM of climb could be reached) was 34,000ft for the Spitfire (note that the Hurricane could do just 100FPM at that height) and 31,400ft for the Hurricane. Climb rate at 25,000ft for the Spit was 1660fpm vs the 1260fpm of the Hurricane or about 4 ft for every 3 feet of the Hurricane. at 30,000ft the climb rates were 1020fpm vs 660fpm or about 3 feet for every 2 of the Hurricanes. 
Instead of the 10% difference in performance a comparison of the service ceilings show or the 14% difference in time to 25,000ft there is a 33-50% advantage for the Spitfire between 25,000 and 30,000ft. 

I think something similar happened to the P-40. As it gained weight and lost climb and altitude performance, it lost it much faster or in a larger amount at high altitudes than the "book" figures really show. Going from a "service ceiling" of 33,000ft to 29,000ft means that the "operational" ceiling went down almost as much. Say to 26,000ft? and climbing at even 500fpm is not that good for 1941/42. A 109E was supposed to be good for 1340fpm at 25,000ft and 740fpm at 30,000ft let alone what an "F" was good for.


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## drgondog (Feb 16, 2012)

Shortround - I have a slightly different perspective on the B vs E question. I feel that the critical altitude advantage of the blower gearing for the P-40B of +3000 feet altitude over the E was more of a factor than the apparent weight differential of approximately 300 pounds due to the all .50 caliber battery. 

There is no question in my mind that weight was a key factor, just reflect on where the second gear kicked in for the P-40B when considering performance above 12,000 feet.

While the E was slightly heavier it also had the later Allison 1710 with about 6% more power.


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## tomo pauk (Feb 16, 2012)

The engine from P-40B was producing 1040 HP at 14300 ft, military rating, same as the engine for P-40E at same altitude. The -E's engine was in advantage down low, producing 1150 HP at 12000 ft, military. The supercharger gearing was of the essentially of the same ratio, 8,77:1 (for the -B's engine) and 8,80 (-E's engine). Both were single speed engines, so no second gear here.

Without fuel, ammo pilot, the P-40B weighted just under 6000 lbs, and P-40E 700 lbs more.


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## bowfin (Feb 24, 2012)

Not a favorite, but *Dehavilland Mosquito:*

Bad hydraulic design

According to a WWII crew chief stationed at Shepherd Airfield in World War II, the hydraulics for the Mosquito was powered by one of the engines. The only Mosquito he ever saw was a beautifully marked American one that made an emergency landing on one engine. Unfortunately, (he claimed) the Mosquito's hydraulics derived its power from that one engine, and with that engineout , it meant no hydraulic power, which meant no landing gear.

A belly landing turned the Mosquito's plywood and lacquer airframe into tinder, and the aircraft burned at the end of the runway, with the pilot making good his escape.

I can't vouch for any of this on my own, just a story passed down from a vet.


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## FLYBOYJ (Feb 24, 2012)

bowfin said:


> P-38 Lightning: Everybody was scared to dive in it once the compressibility phenomenon reared its ugly head.


Not true. I worked with guys who flew the P-38 in combat, it was just something to be aware of on earlier models if you did go into a dive.


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