Comments by "Gort" (@gort8203) on "The Bell P-400 “Caribou”; Britain’s Airacobra" video.

The P-51 was designed at the behest of the British Purchase Commission prior to US entry into the war. The US Army saw it and liked it, but was not authorized to spend any money on another fighter plane at that time. There was no prohibition on spending money on attack aircraft, so they ordered the Apache.
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Because it's not true.
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May I ask where you read that?
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@vger9084 Thanks, but even if true none of that is related to the idea that P-39 was envisioned as a ground support aircraft. The Army specification to which was a response was for a high altitude fighter for interception of incoming bombers. Most fighters were also used as ground attack aircraft, and the P-39 had no greater role in that than most other fighters even after it failed to meet the original high altitude specification.
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@vger9084 And Ben Kelsy also wrote the specification for the P-38. Of course generals have the final say, but they cannot envision a plane as a ground support aircraft after it has already been produced as a fighter. The exhaust driven supercharger was removed after the drag study Hap Arnold ordered because of the disappointing performance of the prototype. NACA thought changes such as eliminating the drag of the supercharger scoop would increase the top speed, and it was Larry Bell who proposed acting on this. It seems the supercharger was never going to work, and it was more important to have a higher top speed at best altitude if the aircraft was to be accepted for production as any kind of fighter. It would need more speed to be a fighter, not to be a ground support aircraft, which favors other attributes. I'm not saying the P-39 did not do ground attack, I'm saying the decision that it would still be useful at low altitude for ground attack was made after the turbocharger had already been removed and its performance would never meet the design intent.
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@vger9084 Having done it myself, I suspect you probably misinterpreted or are misremembering what you read as a teen many years ago. Since then, terminology and vernacular have changed as well. In this case, all tactical aircraft are there to support the ground forces. The first job of a fighter is to support friendly troops by preventing attack by enemy aircraft. Their secondary job is to attack ground targets in support of theatre objectives and specific ground operations. That doesn’t make them ground attack aircraft, they are still fighters. I suspect the argument you have been draw into is whether the command of the tactical air forces should be independent of or subordinate to the ground commander, which is a separate discussion not relevant to the design and production of the P-39. It was a fighter and used as such. It was not relegated to the ground attack role and used differently than other fighters like the P-40 just because it did was not suitable as a high-altitude interceptor. At any rate I thank you for trying to answer my original question, and no hard feelings over any disagreement.
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Well actually that is not a point of order, it is an opinion. One I suspect you got from Greg’s P-39 video. I am a Patreon supporter of Greg, but I do not buy that opinion, which is based on a magazine article written by a Bell executive. I think the writer was trying to present the aircraft as relevant even though it had failed to meet its original design intent, while burnishing the reputation of Bell as an innovator. However, the nose is not really more streamlined in terms of the ideal shape in subsonic flow. The airplane was clean in its use of buried heat exchangers, but even so the overall drag was found to be high in reality, which disproves the supposed benefit of the pointy nose. The specification called for a 37mm gun (to kill bombers) which would have been very difficult to install alongside an engine, a problem solved by the then unconventional aft mounted engine. Considering the extra weight of the drive shaft along with the dubious aerodynamic advantages, the 37mm gun remains the most reasonable primary purpose behind the configuration of this aircraft, one that a single magazine article cannot disprove.
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