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The P-63 seems more like a case of just being a more advanced airframe overall. It doesn't seem that unrealistic that the engines used in the P-63 series could have been fitted to variants of the P-39 itself. (though maybe some complications due to added length or change in CoG).
Good enough to be a reasonable substitute for the Mustang had NA not developed that machine on their own, especially if the merlin engined P-63 project had gone though. (Mustang production started sooner and the USAAF didn't put in massive orders for the P-63, so it's hard to say how well they'd have coped with ramping up production compared to what NA managed historically)
US pilots might have continued to complain about the 37 mm cannon, but it doesn't seem unreasonable that 20 mm alternative mountings could have been substituted, or even just another .50 cal.
The F6F was a great fighter by ANY standards, but was not as good as the P-63 and was ALSO never looked at by the USAAF.
Think Me 210 / Me 410. The 210 was a killer and the 410 was a good plane that never caught on. VERY similar to the P-39 / P-63 pair of designs.
Ergo, the P-63 was redundant and no massive retraining was needed for the "new" fighter that no pilot wanted to be assigned to
The installation may HAVE been heavy, problematic, and appaling, but it was deleted because the War Marriel baords disapproved all turbochargers for US fighters except for the P-38 and P-47. They were saved for the heavy bombers because it was anticipated that Europe would require bombing from high altitude, and turbocharger production was low relative to aircraft and engine production.
Tomo, Allison acq`uired the bearing design by US Government insistence. Of course they for paid. But tyhey would never have given the license if not for government insistence.
And that's why I said the trade of supercharger for bearings never happened ... precisely because the bearing license was mandaded well before the 2-stage supercharger was operational ... so it wasn't "on the table," so to speak, at the time. You don't seriously think a US company would license a technology that was making their bearings the only game in town ... unless they HAD to, do you?
If you do, you don't understand US business.
Well gjs238,
Your assertion above is not quite correct. The Allison DID make it to 2-speed.
The XV-1710-131 was similar to the V-1710-97 except it was fitted with a 2-speed (7.485 : 1 and 9.60 : 1), single stage supercharger and had a different comprression ratio (6.5 : 1).
This engine flew in the XC-114 and the YC-116. It didn't make it intoa US fighter, but it flew.
It also isn't much known, so probably almost everyone else thought so, too.
It also made it to 2-stage with the auxiliary stage. It wasn't an integral 2-stage, but was 2-stage.
I have debated the P-63 in here before and do not propose to replicate that in here. Suffice to say I think it could have been a real asset anywhere it was deployed. If you think otherwise, you are free to do so without comment from me. We all know what happened in the end, and what-ifs are unwinnable by either side of an argument.
Hi Tomo,
The F6F was a great fighter for the Pacific Theater of Operations. It could outclimb a Zero and hit hard enough to do damage when it did so. It wouldn't turn with a Zero but could stay in there for about 3/4 of a turn, enough to get off a shot. The acceleration was MUCH better than a Zero. It was the right package at the right time. The P-63 climbed better, was faster (cruised significantly faster), and hit harder ... ergo my statement.
About the P-39 and the turbo, Ben Kelsey was a huge advocate of the turbocharger. He was in the UK in 1939 when Larry Bell proposed to the USAAC and NACA to produce a variant of the P-39 without the turbo. They agreed and the prototype, which was a ton lighter than a production bird was built and verified the perforamcne gains predicted. Kelsey was NOT a happy camper and when the armor and armament and ammunition, etc. was added, the production plane suffered in performance relative to the prototype. But ... production got started.
Meanwhile, President Roosevelt created the The Office of Production Management and the Supply Priorities and Allocation Board in Jan 1941. They had exactly the same function as the 1-year later War Production Board (official title) and they determined where the turbochargers went. In one if their earliest decisions, they allocated turbochargers to only ONE front-line US fighter, the P-38. Had the P-39 been using a turbo at the time, it would have been removed anyway.
In later years, Ben Kelsey lamented not being present when Larry Bell made his sales pitch becuase he felt like the P-39 turbo issues could have been worked out. He said that because they started production without the turbo did not mean it could not have been added back in at any time. All it would take is the turbos and some development work at Bell. They never got the turbos again, even for the P-63, so they went to the auxiliary stage supercharder on the Allison.
Another often-repeated rumor about the P-39 was that it would tumble end-over-end. In fact, NACA and Bell and the USAAC tested P-39 models both in wind tunnels and in 86 test flights and were never able to get them to tumble. Then, in the 1970's in an attempt to see the real truth, an informal study of the spinning characteristics of the P-39 was done. It might never have been done except they found the original spin test model in storage and decided to test it.
When balanced at full ammunition load, it spun normally and would not tumble. When balanced at a no-ammunition load, it tumbled rather often and easily while spinning.
Just goes to show that if testing is not done at the CG envelope extremes, then you really don't KNOW what a palne will do at the extremes of the envelope when pushed hard.
Having spoken with several people associated with WWII aircraft development and procurement over the years, including Ben Kelsey (he visited Purdue University when I was in the aeronautical engineering department and we had a round table with him, our professor, and 20 students), I have concluded that had both the P-38 and P-39 been equipped with turbos, one or the other would have been directed to stop using them. Bell was a small-time outfit compared with Lockheed, and I have great difficulty believing the P-38 would have been the one so ordered. In fact, Kelsey said they could never get the turbos back even when the combat operformance of the P-39 shouted out the need for them. The War Production Board just said no.
Kelsey liked the P-39, but he also liked the P-38. I don't know which one would have been ultimately better, but I suspect that, if for no other reason, the range would have dictated staying with the P-38. According to Ben and to Pete Law (Skunk Works), the turbos were considered difficult items to make enough of, and were rather jealously apportioned out when they were in "short" supply. Remember, a B-17 or B-24 took four each, so a couple hundred turbos would only produce 50 bombers. That made then even MORE hard to get.
The P-38 was a case of throwing all the eggs in one basket, so to speak. It did not turn out badly as the P-38 was the mount of our top two aces for the entire war.
Now, I suppose it is possible I have concluded incorrectly. I feel that a LOT of modern looks at the past come to very incorrect conclusions becauise modern people have no comcept of the attitudes and feelings of the people in charge at the time. Modern young people look at the world in a wholely different way than some who grew up and was about 18 - 25 years old when war broke out does. Some things that modern people feel should have been done would NEVER have even been considered and the person(s) proposing them would have been ejected from the neetings.
I choose to believe Ben Kelsey and Pete Law and the guys who were around and who grew up at the time and who KNOW why things were done the way they were done. Logic has nothing to do with some decisions that were made. They were made for very specific reasons that were never laid down in meeting minutes.
I have debated the P-63 in here before and do not propose to replicate that in here. Suffice to say I think it could have been a real asset anywhere it was deployed. If you think otherwise, you are free to do so without comment from me. We all know what happened in the end, and what-ifs are unwinnable by either side of an argument.
A tidbit on the proposed XP-40H, from Vee's for victory, pg. 184:
The Curtiss P-40H was to have been an Allison powered and turbosupercharged version of the P-40E. At conference at Wright Field on June 10, 1941 Mr. Don Berlin of Curtiss received authority to begin such a project and the Material Division immediately shipped one GE Type B-2 turbosupercharger to Curtiss at Buffalo, New York. By that October the decision has been made to not turbosupercharge the P-40, but instead incorporate the feature into the coming Curtiss P-60. The turbo was to be installed behind pilot in the XP-60.
The excerpt is sourced.
So the Curtiss almost got to build the turbo P-40. But not in March 1938 (when Curtiss submitted the P-36 derivative featuring the V-1710 engine), but more than 3 years after that.
It doesn't change the fact that the P-40 was not intended to use a turbo from the start.
I don't see many young people out there helping to restore the old planes ... it is mostly guys 55 and older. When we're gone, I doubt seriously if many of the flying WWII planes today will continue to fly all that much longer as the skills needed to sustain them die off with us and the ability to fabricate spare parts goes away, too.
This really is an odd issue and more puzzling since most of the range figures on internal fuel seem relatively high for such a limited fuel capacity. (more so given the range is signigicantly longer than the P-39 in spite of being larger and heavier ... and limited range/fuel capacity was one of the biggest shortcomings of the P-39, so failing to address that seems particularly strange)P-63 still had miserable fuel capacity. 126-128US gallons internal.
Centerline armament (and considerably higher RoF than the synchronized guns), same as the P-38s that were field modified to 5 .50s. (still a 20 mm would make the most sense so long as it had an in-flight cocking mechanism to clear stoppages like the P-38 -given the problems with the US Hispanos )Dropping to a .50 through the prop and the P-39/P-63 loose their reason for being. A 5 machine gun fighter brings what to the table vs the existing 4 and 6 gun fighters?
The poor cockpit placement on the XP-37 also would have had to been dealt with. (maybe possible to move the turbo to the rear like the P-60/P-47/P-43, but managing that while keeping fuel tankage decent seems like it may have been a mess)From your earlier post, the XP-37 DID have troubles and so did the XP-39, but finding solutions to the turbo problem was in sight. Had to be since it WAS successful in the P-38 ... eventually, and also in the P-47 from the start. Had the turbo been allowed to be developed on the P-39 as it was for the P-38, they could have worked out an installation. It would have added weight, but would have also given better high altitude performance.
The P-39 being that looked-down upon still confuses me somewhat. Aside from the unpleasant stall/spin characteristics, the P-39 seemed to be in a similar class as the early (single stage) Spitfire or 109 and significantly better performing than the P-40, let alone Hurricane. (shorter range than the P-40 but longer than the Spit or 109 -aside from the stripped-down P-39N with reduced internal fuel)You can make a lot of the same claims for the Edsel automobile ... wrong thing at the wrong time. It could be said of the P-63, too. It looked like a P-39 and there was automatic predisposal to cancel it despite the flight performance. If you improve things, change their looks if the original was a flop.
The F4U would have been most interesting to the USAAF of anything USN/USMC specific. (let alone with it having more trouble fitting as a carrier capable fighter)Then again, the P-51 WAS in quantity production and so was the P-47, both successes if ever there were any for the USA. The F8F had NO chance as a USAAF plane so, despite the potential, it was only looked at by the Navy. The F6F was a great fighter by ANY standards, but was not as good as the P-63 and was ALSO never looked at by the USAAF. The P-63 was a case of too little, too late ... just like the German late-war aircraft (and OTHER weapons) were.
I was actually speaking more for the normal/clean ranges being compared, but I suppose I might also be seeing apples and oranges figures (ie good/ideal cruising for the P-63 vs more average/faster/low alt cruising for P-39). I knoe the ferry range figures are MUCH longer for the P-63, but I'm thinking more in terms of 600-700 miles vs 950 miles. Though on second look, that 950 mile figure is specifically for the P-63D. Not sure if that model had expanded internal tankage compared to others.The reason why the P-63 have had more range than P-39 was the ability to carry 3 drop tanks, rather than just one on P-39. Great for ferrying, not so much for combat on long ranges, where the internal fuel capacity is a major factor.
The P-63 did not carried any fuel in front of the main spar, there was enough space to almost double up the internal fuel capacity. [.quote]
Interesting so, had the requirement been pressed to Bell for extending long-range capability, the existing airframe should have been fairly straighforward to adapt for this purpose? (given the Russian operations, the limited fuel capacity wouldn't have been much of a concern)
Agree. My comments on the .50 were mostly as an interim/stop-gap option for cases where the 37 mm was unattractive and 20 mm was not functioning properly. (without the ability to re-**** M2 Hispano cannons, they were generally too unreliable to service -the Navy got away with that by using excessive amounts of librication wax and grease on the amunition ... not fool proof, but enough to alleviate some of the issues with chamber size and firing pin position -most stoppages were due to lightly struck primers)As for armament, I'd propose deleting gun pods, while chaning the 37mm for belt-fed 20mm. Should give more chances vs. fighters, while giving some speed due to lack of gun pods.
Come to think of it, with the heavy cannon and machine guns and boost limits raised, the P-39D-L should have made pretty good low-altitude interceptors along the lines of the Spitfire L.F. Mk.Vb or even better if they pushed the boost as high as common overboosting on the P-40. (much higher power output than the Merlin 50)
The P-39N was more along the lines of the standard Spit Mk.Vb, the M would be slightly worse there. (the tropicalized versions would have given a bigger performance advantages to the P-39 though ... )
Should have been good for the MTO ... and some PTO operations. I know it DID see some successes in those theaters, but it seems to get much more of a negative reputation than the P-40 for some reason. (if the P-40 was much more often tweaked to raise boost limits on the engine, that alone would have been a huge difference)
The single-stage V-1710 did compare rather favorably with the Merlin 45/50 series on the whole.
I was actually speaking more for the normal/clean ranges being compared, but I suppose I might also be seeing apples and oranges figures (ie good/ideal cruising for the P-63 vs more average/faster/low alt cruising for P-39). I knoe the ferry range figures are MUCH longer for the P-63, but I'm thinking more in terms of 600-700 miles vs 950 miles. Though on second look, that 950 mile figure is specifically for the P-63D. Not sure if that model had expanded internal tankage compared to others.
Interesting so, had the requirement been pressed to Bell for extending long-range capability, the existing airframe should have been fairly straighforward to adapt for this purpose? (given the Russian operations, the limited fuel capacity wouldn't have been much of a concern)
Agree. My comments on the .50 were mostly as an interim/stop-gap option for cases where the 37 mm was unattractive and 20 mm was not functioning properly. (without the ability to re-**** M2 Hispano cannons, they were generally too unreliable to service -the Navy got away with that by using excessive amounts of librication wax and grease on the amunition ... not fool proof, but enough to alleviate some of the issues with chamber size and firing pin position -most stoppages were due to lightly struck primers)
The single-stage V-1710 did compare rather favorably with the Merlin 45/50 series on the whole.