parsifal
Colonel
RAF was very unhappy with the p-39s it received. it is not exaggerating to say they basically wanted to return them and get their money back. This is despite the generally favourable combat comparisons carried out at Duxford
One needs to remember the old axiom has it that the bombers deterimine the altitude at which fighters must fight. In the SWPA, the Japanese sent their bombers over generally at between 18,000 and 22,000 ft., sometimes substantially higher, seldom much lower. The air was generally very humid and heavy but with high levels of turbulence due to the frequent presence of large mountains. While the P-39 could get that high, it took it a long time to do so, so the and the opportunities for high altitude intercepts were few. Effectively, it was all done by about 17,000 ft. It was at its best below about 12,000 ft. Considering that the mountains in New Guinea rose to over 14,000 ft., and in the early days of the conflict both sides were going back and forth over those mountains to get at each other, the P-39 was at an instant disadvantage. Despite some rather fantastic claims by the USAAC units defending Port Morseby after March 1942, IJAAF losses to Cobra equipped units have been shown post war to be largely unsubstantiated.
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The VVS was the other major user of the type. Soviets fought over terrain much like that of Iowa, were based close to the enemy, and the Germans chose to send their bombers over at medium and low altitudes. So none of the factors that worked against the P-39 in New Guinea were present on the Eastern Front.
Also worth noting. An RAF Duxford comparison test of a captured Me 109E and P-39C showed the Bell outperforming the 109 in every category except rate of climb when below 15,000 ft. The P-39 could easily out-turn the 109--it took the 'Cobra less than 720 degrees to get on the tail of an Me that was planted on its tail. So the P-39 should have had no trouble dealing with the 109 at the altitudes common in the East. But this assumes the 109 would accept a full turning fight, which was seldom the case. In the SWPA, however, the P-39 units again opted for manouvre fighting, but this time they were up against an aircraft that excelled at horizontal manouvre. Not only were the P-39s forced to fight at altitudes above where they were competitive, it had to contend with fighters that were much, much more maneuverable than it was. P-39 squadrons routinely stripped off the wing guns to get more performance, and some even ripped out the armor plating (which weighed about 750 pounds) to get yet more performance, preferring to reduce their susceptibility to battle damage (as the Japanese did) at the expense of vulnerability to it.
That said, the P-39 was not a complete failure in New Guinea. The two groups equipped with it--the 8th and 35th--performed quite effectively, but their victory claims are so dicey as to be not worth much consideration. . The two squadrons of the 8FG that relieved RAAF 75 Squadron at Port Moresby at the end of March, 1942, were the only fighter force available to stop the Japanese air onslaught. This they did, although at great cost.
One needs to remember the old axiom has it that the bombers deterimine the altitude at which fighters must fight. In the SWPA, the Japanese sent their bombers over generally at between 18,000 and 22,000 ft., sometimes substantially higher, seldom much lower. The air was generally very humid and heavy but with high levels of turbulence due to the frequent presence of large mountains. While the P-39 could get that high, it took it a long time to do so, so the and the opportunities for high altitude intercepts were few. Effectively, it was all done by about 17,000 ft. It was at its best below about 12,000 ft. Considering that the mountains in New Guinea rose to over 14,000 ft., and in the early days of the conflict both sides were going back and forth over those mountains to get at each other, the P-39 was at an instant disadvantage. Despite some rather fantastic claims by the USAAC units defending Port Morseby after March 1942, IJAAF losses to Cobra equipped units have been shown post war to be largely unsubstantiated.
.
The VVS was the other major user of the type. Soviets fought over terrain much like that of Iowa, were based close to the enemy, and the Germans chose to send their bombers over at medium and low altitudes. So none of the factors that worked against the P-39 in New Guinea were present on the Eastern Front.
Also worth noting. An RAF Duxford comparison test of a captured Me 109E and P-39C showed the Bell outperforming the 109 in every category except rate of climb when below 15,000 ft. The P-39 could easily out-turn the 109--it took the 'Cobra less than 720 degrees to get on the tail of an Me that was planted on its tail. So the P-39 should have had no trouble dealing with the 109 at the altitudes common in the East. But this assumes the 109 would accept a full turning fight, which was seldom the case. In the SWPA, however, the P-39 units again opted for manouvre fighting, but this time they were up against an aircraft that excelled at horizontal manouvre. Not only were the P-39s forced to fight at altitudes above where they were competitive, it had to contend with fighters that were much, much more maneuverable than it was. P-39 squadrons routinely stripped off the wing guns to get more performance, and some even ripped out the armor plating (which weighed about 750 pounds) to get yet more performance, preferring to reduce their susceptibility to battle damage (as the Japanese did) at the expense of vulnerability to it.
That said, the P-39 was not a complete failure in New Guinea. The two groups equipped with it--the 8th and 35th--performed quite effectively, but their victory claims are so dicey as to be not worth much consideration. . The two squadrons of the 8FG that relieved RAAF 75 Squadron at Port Moresby at the end of March, 1942, were the only fighter force available to stop the Japanese air onslaught. This they did, although at great cost.