Comments by "Colonel K" (@Paladin1873) on "Flight of the XP-38" video.

My late friend, Brig Gen Bob Clements, flew P-38s in the Pacific. After the war he flew P-51s. He preferred the P-38 because he had several Mustang engines seize up in flight, which isn’t a big problem with the P-38. He loved the Lightning so much that his moniker became P-38 Bob.
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@AndyFromBeaverton There was an old joke in the AAF that the Mustang could beat the P-38 at every task except returning home with one engine out.
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@donlove3741 The P-51 is a single engine fighter. If the engine seizes, you are now flying a very heavy glider. I have added the word "engine" to my comment to clarify my meaning.
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@julianneale6128 The idea of refitting Merlins to the P-38 was investigated, but the potential gain in performance was offset by the fact that fighter production would lag during the transition period. This was deemed to be an unacceptable tradeoff. Like the Rolls-Royce Merlin engines, the Allison V-1710 underwent constant upgrades throughout the war, as did the P-38's superchargers, intercoolers, and dive recovery flaps. Higher octane fuel also improved the Lightning's performance. The Allison could easily be pushed far beyond the conservative pre-war power settings assigned to it. This was proven by repeated tests conducted during WWII at Wright-Patterson Field and in England by Colonels Ben Kelsey and Cass Hough, respectively. As a result many fighter pilots had the throttle stops removed from their cockpits so they could get maximum performance from the engines during combat maneuvers. Pilots in the Pacific had to fly over very large bodies of ocean. From a psychological standpoint alone, a twin engine aircraft, even with potentially inferior engines, was much preferred to a water landing if an engine was lost.
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@julianneale6128 I never said the Allison did not seize up, nor did I say it was more reliable than the Merlin. I said my late friend preferred the P-38 because losing one engine wasn't a big problem. For a Mustang or any other single engine aircraft, it was a very big problem indeed. This is an example of the law of probability at work and has nothing to do with engine reliability unless you have truly terrible engines. I do not consider our main combat aircraft engines of WWII, the Allison, Packard/RR Merlin, Pratt & Whitney R-2800, and Wright Cyclone, to be unreliable engines for their time, if properly maintained. I don't know which one was the most reliable, but I suspect it would be the P&W, due to its simplicity and ruggedness. Of course there are many other factors that go into this equation, and it would make an interesting topic for discussion.
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