Improve That Design: How Aircraft Could Have Been Made Better (1 Viewer)

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So if all this was true why didn't at happen Expert, why did the US leave their most valuable A6M killer back in the states or used it for secondary roles when quite clearly it would have turned the tide in the Pacific?.
The 1942 P-39s (D/F/K/L) were very overweight for the power available (V-1710-35/63) and had a hard time cruising over 18000ft with the ever-present drop tank. Almost every combat with the A6M2 Zero or Ki-43 Oscar began with the Japanese planes making a firing pass from above. Not fun. At all. Those 1942 P-39s did fight the Japanese planes to a draw despite inexperienced pilots because they were about 40mph faster and had armor protection. But pilots hated them (along with the P-40) because they had to give the Japanese the first punch, and intercepting high flying Japanese bombers (18000-22000ft) was an iffy proposition.

The decision had already been made by the AAF brass that the war would be fought with turbocharged P-38 Lightnings and P-47 Thunderbolts. Problem was they didn't have enough of them yet until the P-38F/G got into combat in very late 1942 and the P-47C in April 1943. The P-39 and P-40 would be exported under lend-lease to our allies or used for training by the AAF.

By November 1942 the -85 engine with the 9.6 supercharger gears was in the P-39N which was the best performing model of the P-39 series. It was faster under 20000ft and would outclimb and out turn both the early P-38F/G and the P-47C/D. It dived better than the P-38 and had about the same endurance as the P-47. Ceiling was competitive with both. And the P-39 was inexpensive compared to the ultra-expensive Lightnings and Thunderbolts. But the AAF had four fighters in production and the Merlin P-51 was being put into production too.

The P-39 (and P-40) would have benefitted from the two stage -93 engine that was in production in April 1943. But the field was crowded and the decision had been made to emphasize the turbo P-38 and P-47.
 
As I pointed out, at the time of those trials in August 1942, frontline P-39 units were using the 'D model, not the 'N model. And despite the P-39N's obvious advantages compared to the earlier models, by 1944, when the P-39N has reached the frontline and had been equipping for around a year, the P-38, P-47 and P-51 were the AAF's primary fighters across both the PTO and ETO. That the P-39 remained in service beyond 1943 was down to the numbers game - the AAF needed fighters and the P-39 was available, warts 'n all. If the AAF could have equipped all its P-39 units with any of the other fighters it probably would have. They offered significant advantages over their enemies the P-39 did not possess.
 
You have about 3 things going on in late 1942, maybe more.

1, the change to the 9.60 supercharger gears on the single speed/single stage Allison. These are not magic, they do improve altitude performance by about 4,000ft. (What plane powered by the older engines could do at 13,500 it could now do at 17,500) which is not enough to make the P-40 and P-39 effective fighters at 20,000ft and above unless they lost a LOT of weight.
2. The US was late to party when it came to overboosting engines. A lot of testing was going on, some squadrons were overboosting in the field. Officially The US did not approve over boosting until Dec of 1942 (after the tests of the P-39N).
3. It took the US about 3 to 6 months to get a fighter from the factory door to an operational combat unit overseas. In the case of the P-39N the first ones rolled out the door in Nov 1942, They showed up in North Africa in April (?) of 1943 and at Henderson field in June of 1943. Shipping space arrangements and allocations of aircraft were often made before the actual planes rolled out the door.

Decisions as to which planes to send where in the first part of 1943 were made before the test flights of the P-39N. And the test flights using WEP settings in the P-39N showed some serious problems. THE USAAF and Allison called for a max cooling temperature of 250 degrees F or 121 degrees C .

We may well consider that P-39 use the Soviet union was quite different due to the Soviets acceptance of lower service life between overhauls and the usually colder temperatures the engines were operating in. You could get hot temperatures in southern Russia in the summer but lets face it, The P-39N was overheating using WEP in Buffalo New York in Oct and barely exceeding the allowable in limit in November.

Correction from Wuzak
 
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Either that was a type or Henderson Field was using a time machine.
 

SwampYankee,

I can't help but agree that all three of your points are good. However, point number 2 has always dumbfounded me. It would have made transition from one to the next much easier and safer.

Cheers,
Biff
 
SwampYankee,

I can't help but agree that all three of your points are good. However, point number 2 has always dumbfounded me. It would have made transition from one to the next much easier and safer.

Cheers,
Biff

Thank you.

Panel design is something where, I think, the NACA, USAAC/USAAF and USN could have actually agreed on in the early 1930s. A lot of the panel designs looked like something a drunken frat boy puked up after a hard night of drinking.
 
In production and available in meaningful numbers are two different things.

In any case, Bell was working on the P-63 to use the 2 stage engine.

It took until the fall of 1943 to clear the 2 stage engine for WEP ratings. This including things like the new keystone piston rings.

Without the WEP/water injection the V-1710-93 engine was rated at 1180hp at 21,000ft
which is about 200hp less at 2,500ft lower than the Merlin 61 of spring/summer of 1942, one year earlier.

First P-63s built with the engine flew under restrictions until the engine was cleared.
 
Thank you.

Panel design is something where, I think, the NACA, USAAC/USAAF and USN could have actually agreed on in the early 1930s. A lot of the panel designs looked like something a drunken frat boy puked up after a hard night of drinking.

I have attached the cockpit panel of the mighty T-37 Tweet. This nightmare was in use into the 2000's. Plane was designed for day visual flight rules and morphed into a full Instrument Flight Rules (IFR) jet. Oh, and it held very little fuel. But at least it was loud, and the A/C sucked...

Cheers,
Biff
 

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One of the big improvement they COULD have made to the F6F was to remove the dihedral from the outer wing panels. The decision was not to interrupt production to make the F6F roll much better. Instead, they developed the F8F Bearcat while producting the F6F-5. The F6F-6 was the fastest Hellcat, but they only built 2 of them ...
 
From time to time while he was still in his career he would call and I'd listen to war stories. Before he retired, I asked him if it turned out as well as he hoped at the start. He said, " listen Ed, I get up and look outside and it's a beautiful day. I call ops and ask for a plane. (He was flying F-16s then). I go down check out, get in the bird they fueled, and go flying. It's great and they pay me to do it."
 
Answers above.
 
See above.
 

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