Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)

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Yes the British were experimenting in the BoB with cannon, that was a year before the P-39 arrived in UK. You have repeatedly quoted the performance of your 1942 super light P-39 as being useful in Europe, even suggesting it could be used as a bomber escort.
 
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I think you are mixing a little bit of truth but then extrapolating it to prove a point using a falsehood

Let me explain
Yes the British were still using 30calMGs after the BoB, but the AAF WAS NOT. Except for the P-39. The British were using a few 20mm cannon in the BoB, but VERY VERY FEW on an experimental basis. They were unreliable and didn't hold enough ammunition at that stage of their development

This is of course absolutely true but irrelevant in the P39 saga. When the British first equipped a squadron with the P39 in Mid 1941 the Spitfire IIb and Vb had been in service for some months with a reliable 20mm and the Vc was entering production and service which had both a reliable 20mm and more ammunition. Something I don't think you have ever acknowledged. The Hurricane IIc was also entering production and service with 4 x 20mm

First, nobody can prove British intent. I can't prove that the British intended to make the P-400 too heavy to make the performance guarantee.
Actually its almost impossible to prove that something that didn't happen. But its what isn't there that proves that the British never intended to ruin the P39 so it could fail the performance guarantee. Bell had a huge amount riding on the P39 and if they had even suspected that things were being done to effectively sabotage its performance, they would have been screaming from the rooftops. The papers would have been full of it and politicians who love this kind of thing would have been causing merry hell.

So when you say I can't prove that the British intended to make the P-400 too heavy to make the performance guarantee. Your wrong, you can, we are just asking you to do it instead of stating a statement without any evidence.

The steps are simple for an expert such as yourself
a) Find any demand that the UK made that wasn't already being installed on their own aircraft
b) Find any complaint from Bell that demands were excessive and designed to ruin the aircrafts performance
c) Find any legal proceedings along these lines
d) Find any paper or politician sounding off about this scandal

We await your response with interest
 

Supposed to be wrecks of P-40s destroyed at Pearl Harbor which I believe was Dec 7th 1941.
P-40s with nose guns used .30 machine guns in the wings.
The BoB was over 1 year earlier.

"Yes the British were still using 30calMGs after the BoB, but the AAF WAS NOT. Except for the P-39."

Obviously false.
The AAF may not have been installing .30 cal guns in new fighters but they were certainly using them well after the BoB.
BTW the last P-40C was delivered to the AAF, complete with four .30 cal wing guns, In April of 1941.
 
My point was very simple, dates and details actually obscure the point. All sides were trying to increase armament in all sorts of ways, you cant make a case for any request about armament being a conspiracy against the P-39 by the British and you cant make a case for rifle calibre ammunition being so useless it shouldnt have been fitted. Fitting of cannon to British aircraft reduced top speed, the cannon were fitted and the top speed reduced because cannon were more important than absolute top speed. If the thing had done 400 MPH at the start it wouldnt have mattered.
 
No AAF or USN fighters used 30s in WWII except the P-39. They were redundant on a plane with cannon and heavy MG

As pointed out by others, the P-40 did.

Also note that the Mustang I supplied to the RAF had 4 x 0.50" and 4 x 0.30" machine guns.

It shows that the 3 gun armament was deemed insufficient by the Western Allies. Even the 4 gun P-51A and P-51B were considered under-gunned, hence the 6 gun P-51D.

The P-39 couldn't fit the 0.50" inside the wing, from what I understand. So the only option was 0.30" mgs (until they stuck on the gondolas).
 
According to this the first P-40s to arrive in UK had two x 0.5" synchronised guns. The Pesky British seeing another chance to have no planes in Africa asked for 4 x 303s to be put in a redesigned wing. Mr Curtis said "you aint getting outta this contract" and produced them, Uncle Sam said "thats a mighty fine pair of wings I see there, can I have some", so that became the P-40G, Uncle Sam kept some and sent some to his friend Joe. 4 x 0.5" wing guns became the standard armament.


cant copy from the link, 5th paragraph down
 
This nonsense about the AAF not using fighters with .30s, it has to stop. P-40Bs were deployed to Hawaii, the Philippines, and the Canal Zone pre war. In the Philippines were also P-35As. Also stationed in Hawaii were P-36As and P-26s. P-36s were also stationed in Alaska. This does not include the multitude of other fighters based in CONUS. The 23rd Fighter Group, in July 1942, absorbed the remaining H-81A-3s originally equipping the AVG. (OK, you can argue that the ex-AVG planes were armed with .303s and 7.92mm, but the point is they continued to serve as combat aircraft well into 1943.) It is true that Curtiss was already responding to armament upgrades prior to Pearl Harbor, and the USAAF did not order any more fighter aircraft with .30s except the P-39, but remember, two P-39 equipped fighter groups destined for North Africa were re-equipped with Spitfire VBs in late 1942. Does using .303s exempt them from the charge that the USAAF never used .30s except in the P-39? These groups would eventually receive Spitfire IXs as replacements before converting to P-51Bs in 1944. So rifle caliber weapons continued to serve in USAAF fighters other than the P-39 until fairly late in the war. P-39s were a stop gap. Nobody wanted them (except the Russians.) They continued to serve honorably until they could be replaced by more capable fighters as these became available.
 
Dang, I forgot about the venerable 4th Fighter Group (ex-Eagle Squadrons) in England that transferred wholesale from the RAF to the USAAF and brought their Spitfires with them.
It is a typical groundhog argument. The USA wasnt in the war until 13 months after the BoB ended so what is "using". Had every US aircraft been switched to 0.5s? Obviously not. Was a plane shipped new and used after Oct 1940 with 0.3mgs? Yes. But many or most were changing to 0.5" which proves Uncle Sam was trying to get out of contracts more than the Brits, or maybe Uncle Sam like everyone else just wanted more firepower and no other supplier had an issue.
 
I'm not sure what he's trying to get at. He seems to be trying to say that the P-39 was unfairly saddled with inadequate armament. But the RAF continued to use rifle caliber guns on their fighters throughout the war. Not all fighters, but a substantial portion of them. And if we look at 1941, when the P-39 is introduced, nearly all operational fighters in the RAF rely on a mix of cannon and rifle caliber mgs or large batteries of .303 caliber mgs. His argument that the RAF tanked the performance of the P-39 by demanding that it have similar firepower to its existing stable of fighters is absurd.
 
There are two arguments.
1 that the P-39N when lightened could be useful in the far east, others have answered that in detail.
2 Once argument 1 is accepted the requests of the British are said to be unreasonable and the P-39 could have been useful in Europe in 1941-42 and the British should have kept it.

The British wanted 4 cannon on all fighters like the Mustang, Hurricane II Typhoon Tempest.
The Spitfire was the exception because it was always the high altitude fighter, the weight of 4 cannon affected performance at high altitude and it was difficult to keep them warm. They kept the extra 4 x 303 because they were better than nothing, capable of taking down an enemy fighter just not as capable as others. In firepower the two cannon were about the same as 6 x 0.5" so it was a bonus not desperation. When the UK became awash with 0.5" ammunition the Spitfire got 2 x 0.5" which gave a trajectory closer to that of the cannon.

Armour was fitted to the Spitfire first in front of the pilot, then behind, until the possibility of France falling came into peoples minds it hadnt been thought needed because only bombers would be coming to UK.

There was a war on, without all this stuff you would just be killing your own pilots, which are more valuable than the plane itself. If you sell weapons to someone you cant start telling him what sort of fight to use it in, or what he needs, when he has been in the fight for 2 years.
 
In reverse order.

Oh, boy.
The British had been rushing the 20mm Hispano gun into production since 1938, if not earlier.
The British MARC company deed of partnership was registered on Jan 11th 1938.
The title deeds for the for the plots of land for the buildings were recorded in June of 1938 and the first prototype guns were being built and tested started in Jan 1939.
At the official opening of the factory in Jan 1939 the Duke of Gloucester fired the first British HS-404 cannon.
British were planning on putting 20mm cannon into existing designs and not wait for new designs in the Spring of 1940, well before the BoB.
Yes it took a while to get the numbers desired/needed.

Hundreds of German aircraft destroyed during the BoB might show a different result than "proven ineffective" this has been gone over many times. Likes the "ineffectiveness" of The Japanese 7.7mm (.303) guns.
As for the "effective range of the .30 cal or .303. How about you park you car out in field and let me shoot 40-60 rounds at it with a 30-06 or .303 rifle at 400yds (double the distance at which the .30 cal become ineffective) and then tell me how ineffective they are.



Switching the goal post on the heater???
Did the British ask for it or take what was offered? You claim the British asked for it. Was the new heat system offered to the French? Did the British change it back?
The IFF was useless in 1942 NG because there was no accurate radar until fall. The British DID order it but once the P-400s were diverted to NG the IFF would have been removed. To save the weight.
Another switcheroo. You claimed the British added unneeded weight to get out of the contract. IFF was needed in 1940-41 and 42 over Britain and in the contested space over the channel.
changing your tune? You claimed the British made the P-400 too heavy so as to get out of the contract, Now you are saying you can't prove it. But you still want us to believe it.

As for the British KNOWING that the 7850lb P-400 with 1150hp engine couldn't go 400mph?
If they knew that they should have told North American to quit fooling around with the NA 73 and just build P-40s.
British tested an 8600lb Mustang I at 370mph with an 1150 hp (?)engine.
Aircobra tested in England was 800lb lighter, used the same engine and was 15mph slower.

Power vs drag determines speed, not power vs weight.
Expecting a smaller, more streamline plane, even if heavier, to make a higher top speed than a larger/older/higher drag airplane was not unreasonable. Difficult but not impossible.
Bell flubbed it, big time.
 
It's worth noting that one of the main reasons why the RAF rejected the Airacobra was compass deviation when its guns were fired, at rates as high as 160 degrees, which rendered it completely useless. This was clearly unacceptable to the British, but eventually, a fix was found, although by that time the decision had been made to replace the Airacobras in service with Spitfire Vs, which had better performance at any rate. Did the US forces ever record this as an issue with the P-39?
 
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For the Americans and British the BoB didn't "prove" much of anything.
The P-40D with four wing mounted .50s was officially ordered in Sept of 1940.
The idea of sticking the -39 engine in the P-40 airframe instead of building the P-46 was several months earlier.

As far as the "unreasonable" armament requirement goes. The Original Mustang Is carried.
Two fuselage .50 cal guns..................................128lbs
Two wing .50 cal guns..........................................128lbs
four .303 wing guns ................................................86lbs
400 rounds for the
fuselage .50s..............................................................100lbs
612 rounds for the
Wing .50s....................................................................152lbs
3492 rounds for
the wing .303............................................................227lbs.

total, guns and ammo..........................................821lbs

Just think of the speed and climb of the Mustang I if the useless wing guns had been deleted

Edit, BTW the Mustang I used as Stewart-Warner (where have we heard that name before )fuel heater to warm the wing gun bays.
 
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Don't know.
Larry Bell's solution to the low performance of the P-39/P-400 was to get rid of such frippery as the compass. Likewise all blind flying instruments.
 
The early P-40Ns were stripped of quite a bit of stuff, as I am sure you know, in an attempt to significantly lighten the airplane.
Most of the stuff was put back in by the service squadrons.
The extra performance wasn't worth the loss in operational capability.

The "stripper" P-39 was pretty much down to an airspeed indicator, an altimeter and few engine gauges (to keep from cooking the the engine) also the oxygen system was removed. Pretty much anything that wasn't needed to fly at 5,000ft.
 
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The extra performance wasn't worth the loss in operational capability.

From what I've read about the P-40s the modifications did little to improve performance in the 'N model. Some non-structural parts were replaced with 'plastic' parts, such as the map case, etc, to save weight.

I can vaguely remember hearing about an incident where P-40s escorting B-24s in either Papua or the Solomons, flew into a mountain when they got lost in fog because they had no instrument flying capability.
 

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