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The P-39 why a failure for the West and a winner in Russia?

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  • #16
    Originally posted by Michele View Post

    We automatically assume that instability, or a tendence to instability, is a bad thing. Yet, stability means more effort, or more time, or both, when you want something to change trim, position, and therefore direction. Instability means faster, easier responsiveness when you want to achieve that sort of change.
    Then, it's easy to understand that for a fighter aircraft, fast and easy responsiveness is an advantage, not a drawback. It means better maneuverability.

    Also note that for high-speed, high-power fighter tactical maneuvers at high altitudes, maneuvering mainly means diving and climbing. That's what the Germans and the Western Allies mainly did, jockeying around bomber formations. A stable fighter can still be very good at diving and climbing. Engine power, and consequently speed, is what matters there.
    But if you are close to the floor because you are hunting German ground attack aircraft, then diving is a... shallow option, and horizontal maneuvering - à la WWI - is much more important.
    Do not confuse issues of manoeuvrability and stability. During WW1 Morane Sauliner fighters had no fixed tail fin or planes which meant that they were laterally and vertically unstable and the pilot had to be constantly correcting for this which made them very tiring to fly for any period. The SE5a was both stable and manoeuvrable which meant that pilots could fly long patrols making almost no corrections and still be able to dog fight when needed. In WW2 the Mustang had similar useful characteristics
    According to Tex Johnston, a test pilot for Bell, The problem with the P-39 was that if it had not been properly trimmed it was very easy to get into an inverted spin from which even an experienced pilot could have problems extracting the aircraft (he quotes one of the Russian test pilots attached to Bell having to bail out as a result). What made the problem worse he said was that many pilots mistook the spin for tumbling and took entirely the wrong corrective action. He quotes Colonel Kertchetkoff the senior Red Air-force pilot attached to Bell as saying that the P-39 was a good aircraft because of its heavy armament. Given that the Soviet Union did not produce such heavily armed fighters until 1943 and Luftwaffe aircraft were comparatively well equipped with armour and self sealing tanks etc this may well have been deemed worth living with stability problems for.

    In the Pacific theatre where Japanese air craft were much less well protected and could be knocked down with machine gun fire that big cannon may have been seen as less of a major advantage to offset against other issues.
    Human history becomes more and more a race between education and catastrophe (H G Wells)
    Mit der Dummheit kaempfen Goetter selbst vergebens (Friedrich von Schiller)

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    • #17
      Originally posted by MarkV View Post

      Do not confuse issues of manoeuvrability and stability. .
      I'm not, thank you. The two are not the same thing, but they are related - as I explained.



      Michele

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      • #18
        For the Russians the P-39 was also a much better plane, both in equipment and aerodynamic characteristics to many of their own. The MiG 1 and 3 are noted as being dangerous to fly in anything other than a straight line almost. The LaGG 3 was considered a flying death trap. Wooden and fabric construction is more vulnerable to damage in many cases compared to an all-metal aircraft.

        The P-39 also always came with a radio that worked, had an oxygen system fitted that worked, and an armament as heavy or heavier than anything the Russian designers were putting on their planes.

        The USAAF's pilots' biggest complaint with the 37mm was it jammed regularly. To clear the jam, the pilot had to reach down on the floor between his legs, and pull the cocking lanyard up about even with his ear to do this. It often took the strength of both hands to do this as well. That's like trying to cock a PIAT in the middle of a bayonet charge...

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        • #19
          Hi Terry

          In Phillip Butler's and Dan Hagedon book 'Air Arsenal North America-Aircraft for the Allies 1938-1945 Purchases and Lend-Lease' they state on Pg150 that one of the main reasons the RAF shunned the plane was that "the biggest operational problem turned out to be the fitment of the navigational compass, which was such as to render it useless after the aircrafts guns had been fired. Although this problem could have been overcome in time, it proved to be an embarrassment at a crucial time during the types introduction into RAF service"

          Regards

          Andy H
          "You have enemies? Good. That means you've stood up for something, sometime in your life." Churchill

          "I'm no reactionary.Christ on the Mountain! I'm as idealistic as Hell" Eisenhower

          Comment


          • #20
            Originally posted by Andy H View Post
            Hi Terry

            In Phillip Butler's and Dan Hagedon book 'Air Arsenal North America-Aircraft for the Allies 1938-1945 Purchases and Lend-Lease' they state on Pg150 that one of the main reasons the RAF shunned the plane was that "the biggest operational problem turned out to be the fitment of the navigational compass, which was such as to render it useless after the aircrafts guns had been fired. Although this problem could have been overcome in time, it proved to be an embarrassment at a crucial time during the types introduction into RAF service"

            Regards

            Andy H
            I would think that the British military procurement system had one of the worst cases of "Not invented here" syndrome in history during the 20th Century. Seems to me that any piece of kit or equipment not specifically invented in Britain to an official request was somehow deficient giving grounds for rejection. I read a report on the British Army testing the Czech TNHP-S (aka Pz 38t). The report noted that the tank jittered and the vibration when in motion made it hard to aim the gun. Overall, it stated that the Czech tank was markedly inferior to the Light Tank Mk VI. Nothing was noted about the armor being better, it having an actual cannon versus a .303 machinegun (or later .50 machinegun) or that the Mk VI would have had a hard time dealing with a TNHP on the battlefield because of that. But, somehow the Czech tank was found "inferior."

            That's one example of many I've come across.

            In the US, the Army's ordinance department had / has much the same problem. The USAF for several decades was loathe to use USN developed planes and missiles even as their own proved poor by comparison. So, this isn't limited to Britain.

            It's interesting to note I've never read about this problem anywhere else.

            Comment


            • #21
              Originally posted by Andy H View Post
              Hi Terry

              In Phillip Butler's and Dan Hagedon book 'Air Arsenal North America-Aircraft for the Allies 1938-1945 Purchases and Lend-Lease' they state on Pg150 that one of the main reasons the RAF shunned the plane was that "the biggest operational problem turned out to be the fitment of the navigational compass, which was such as to render it useless after the aircrafts guns had been fired. Although this problem could have been overcome in time, it proved to be an embarrassment at a crucial time during the types introduction into RAF service"

              Regards

              Andy H
              As I understand it,a major reason for its rejection was the lack of a fitted supercharger, as supplied.
              The Bell Aircraft Corporation did not lack innovative thinking at the time, there was the FM-1 Airacuda.
              "I dogmatise and am contradicted, and in this conflict of opinions and sentiments I find delight".
              Samuel Johnson.

              Comment


              • #22
                Originally posted by T. A. Gardner View Post

                I would think that the British military procurement system had one of the worst cases of "Not invented here" syndrome in history during the 20th Century. Seems to me that any piece of kit or equipment not specifically invented in Britain to an official request was somehow deficient giving grounds for rejection. I read a report on the British Army testing the Czech TNHP-S (aka Pz 38t). The report noted that the tank jittered and the vibration when in motion made it hard to aim the gun. Overall, it stated that the Czech tank was markedly inferior to the Light Tank Mk VI. Nothing was noted about the armor being better, it having an actual cannon versus a .303 machinegun (or later .50 machinegun) or that the Mk VI would have had a hard time dealing with a TNHP on the battlefield because of that. But, somehow the Czech tank was found "inferior."

                That's one example of many I've come across.

                In the US, the Army's ordinance department had / has much the same problem. The USAF for several decades was loathe to use USN developed planes and missiles even as their own proved poor by comparison. So, this isn't limited to Britain.

                It's interesting to note I've never read about this problem anywhere else.
                That flys in the face of my impression. The situation was so dire in the early years of the war that any product from any source was received with appreciation.
                What other examples had you in mind ?
                "I dogmatise and am contradicted, and in this conflict of opinions and sentiments I find delight".
                Samuel Johnson.

                Comment


                • #23
                  Originally posted by BELGRAVE View Post

                  That flys in the face of my impression. The situation was so dire in the early years of the war that any product from any source was received with appreciation.
                  What other examples had you in mind ?
                  The SB2U Chesapeake was claimed to be "underpowered" and relegated to training at a time when the FAA was still using the mediocre Skua.
                  The RAF said the F2B Buffalo had numerous failings but issued them in Malaysia and the Med (Crete) anyway.
                  Then there's the Curtiss Hawk 75. It was tested against early Spitfire I's with fixed props and beat them. The RAF acquired a bunch of ex-French ones and sent them to India (among other odd corners of the empire) declaring them "obsolete" for frontline service. In India they gave excellent service right through 1944 even though it was officially "obsolete."

                  Then you have Lt. Gen. Sir Giffard Martel in his book Outspoken Soldier saying this about the Sherman:

                  "The Sherman tank was a dual purpose tank and was a very sound and reliable machine, but it was not as good as either the Cromwell or Churchill for their respective roles. We were most grateful for the use of these tanks to cover this period (when neither British tank was available in quantity, or at all) and continued to use some Shermans right up to the end of the war."

                  That is so condescending it isn't funny. The Sherman wasn't some stop-gap. It was easily the most important and widely used tank in British service form 1943 to the end of the war.

                  There's a few.

                  Comment


                  • #24
                    Originally posted by T. A. Gardner View Post

                    I would think that the British military procurement system had one of the worst cases of "Not invented here" syndrome in history during the 20th Century. Seems to me that any piece of kit or equipment not specifically invented in Britain to an official request was somehow deficient giving grounds for rejection. I read a report on the British Army testing the Czech TNHP-S (aka Pz 38t). The report noted that the tank jittered and the vibration when in motion made it hard to aim the gun. Overall, it stated that the Czech tank was markedly inferior to the Light Tank Mk VI. Nothing was noted about the armor being better, it having an actual cannon versus a .303 machinegun (or later .50 machinegun) or that the Mk VI would have had a hard time dealing with a TNHP on the battlefield because of that. But, somehow the Czech tank was found "inferior."

                    That's one example of many I've come across.

                    In the US, the Army's ordinance department had / has much the same problem. The USAF for several decades was loathe to use USN developed planes and missiles even as their own proved poor by comparison. So, this isn't limited to Britain.

                    It's interesting to note I've never read about this problem anywhere else.
                    Hi Terry.

                    It also states that the problem was probably due to the magnetisation of steel parts in the structure induced by firing.

                    The not invented syndrome was prevalent in all militaries to some degree (and still is now for nationalistic or political reasons) but I've not come across anything in relation to your particular question, that the RAF 'dumped' it for any other reasons than technical/performance issues. In fact, the British contracts of considerable numbers would lay waste to that argument having any relevance.

                    The RCAF also considered building the plane under licence but abandoned because of the non-availability of engines.

                    Regards

                    Andy H

                    "You have enemies? Good. That means you've stood up for something, sometime in your life." Churchill

                    "I'm no reactionary.Christ on the Mountain! I'm as idealistic as Hell" Eisenhower

                    Comment


                    • #25
                      Originally posted by BELGRAVE View Post

                      As I understand it,a major reason for its rejection was the lack of a fitted supercharger, as supplied.
                      The Bell Aircraft Corporation did not lack innovative thinking at the time, there was the FM-1 Airacuda.
                      Hi Belgrave

                      Your not wrong that the powerplant was a major issue along with the other aspects already mentioned. I've just come across the issue of the compass as stated in the book. It mentions in the book that the French Aircobra orders had also specified the fitment of engines with a single stage mechanical superchargers, to provide spares and maintenance communality with engines ordered for French bombers purchased in the USA.

                      Regards

                      Andy H
                      "You have enemies? Good. That means you've stood up for something, sometime in your life." Churchill

                      "I'm no reactionary.Christ on the Mountain! I'm as idealistic as Hell" Eisenhower

                      Comment


                      • #26
                        Originally posted by T. A. Gardner View Post

                        The SB2U Chesapeake was claimed to be "underpowered" and relegated to training at a time when the FAA was still using the mediocre Skua.
                        The RAF said the F2B Buffalo had numerous failings but issued them in Malaysia and the Med (Crete) anyway.
                        Then there's the Curtiss Hawk 75. It was tested against early Spitfire I's with fixed props and beat them. The RAF acquired a bunch of ex-French ones and sent them to India (among other odd corners of the empire) declaring them "obsolete" for frontline service. In India they gave excellent service right through 1944 even though it was officially "obsolete."

                        Then you have Lt. Gen. Sir Giffard Martel in his book Outspoken Soldier saying this about the Sherman:

                        "The Sherman tank was a dual purpose tank and was a very sound and reliable machine, but it was not as good as either the Cromwell or Churchill for their respective roles. We were most grateful for the use of these tanks to cover this period (when neither British tank was available in quantity, or at all) and continued to use some Shermans right up to the end of the war."

                        That is so condescending it isn't funny. The Sherman wasn't some stop-gap. It was easily the most important and widely used tank in British service form 1943 to the end of the war.

                        There's a few.
                        Interesting. If, your sensitive to such things,of course, a degree of condescention can always be detected. But as against your examples, there are numerous examples where US weaponry: - aircraft,in particular,were adopted with enthusiam, modified, where necessary:-witness the P-51 Mustang, or the Sherman Firefly.
                        Can the same be said in the opposite direction ?
                        "I dogmatise and am contradicted, and in this conflict of opinions and sentiments I find delight".
                        Samuel Johnson.

                        Comment


                        • #27
                          The reason the Soviets liked it and the US didn't is three-fold:

                          1) The US had better aircraft (as you showed, the P-40, and even better aircraft following hard on its heels)

                          2) Range. The PTO was the main air-combat theater, followed by North Africa; both required longer-legged aircraft. By the time the Italian campaign got going there were much better aircraft entering service.

                          3) The Soviets were desperate for anything that came to hand, and were willing to accept pilot losses. The US was concerned with survivability, whereas the Soviets were locked in a war to the death on their own soil, so there are completely different values.

                          Comment


                          • #28
                            Originally posted by Andy H View Post

                            Hi Terry.

                            It also states that the problem was probably due to the magnetisation of steel parts in the structure induced by firing.

                            The not invented syndrome was prevalent in all militaries to some degree (and still is now for nationalistic or political reasons) but I've not come across anything in relation to your particular question, that the RAF 'dumped' it for any other reasons than technical/performance issues. In fact, the British contracts of considerable numbers would lay waste to that argument having any relevance.

                            The RCAF also considered building the plane under licence but abandoned because of the non-availability of engines.

                            Regards

                            Andy H
                            I do know the RAF did complain the take off run of the plane was longer (750 yards) than for other aircraft meaning it couldn't use many RAF fields, the speed was found to be lower than the manufacturer had stated by about 30 mph, and dangerous levels of carbon monoxide and fumes from the guns firing accumulated in the cockpit. The 15,000 foot critical altitude was also a big issue.

                            Comment


                            • #29
                              Originally posted by BELGRAVE View Post

                              Interesting. If, your sensitive to such things,of course, a degree of condescention can always be detected. But as against your examples, there are numerous examples where US weaponry: - aircraft,in particular,were adopted with enthusiam, modified, where necessary:-witness the P-51 Mustang, or the Sherman Firefly.
                              Can the same be said in the opposite direction ?
                              With the Firefly I can see the objections raised were kind of valid. The Firefly while a good tank on tank weapon, was a pretty big compromise the US Army wasn't willing to make. Add that the installation as done by the British was somewhat Rube Goldberg and improvised. That didn't help matters.

                              The USAAF did operate a fighter group in the Med flying Spitfires. In fact, it had the highest air to air kill rate of any US fighter group. But, it got little press because of the "not invented here syndrome." The USAAF also operated several squadrons of Beaufighter night fighter planes due to the lack of one being developed in the US at the time.

                              http://spitfiresite.com/2010/04/uncl...spitfires.html

                              Comment


                              • #30
                                Originally posted by T. A. Gardner View Post

                                I do know the RAF did complain the take off run of the plane was longer (750 yards) than for other aircraft meaning it couldn't use many RAF fields, the speed was found to be lower than the manufacturer had stated by about 30 mph, and dangerous levels of carbon monoxide and fumes from the guns firing accumulated in the cockpit. The 15,000 foot critical altitude was also a big issue.
                                Hi Terry

                                In regards to the speed it seems that Bell, stripped the plane basically down to its bare bones, even devoid of paint to achieve its much lauded speed from which many orders were initially placed.

                                The bulk of the contracts in place when the RAF decided against the P39 were for the I & IA models. The contracted P39D planes were turned over to the US after they entered the war, who gave them the designation P400 and were used mainly for training intially-though some did see combat later on.

                                Some 200 odd P39 served with the Italian AF after the armistice and saw action against the Axis mainly over Yugoslavia in 44/45

                                Regards

                                Andy H
                                "You have enemies? Good. That means you've stood up for something, sometime in your life." Churchill

                                "I'm no reactionary.Christ on the Mountain! I'm as idealistic as Hell" Eisenhower

                                Comment

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