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Of this I was aware.
The Merlin doesn't have to be the 1650-3. The V-1650-1 could give a useful altitude performance gain without much weight penalty, and it shouldn't require the massive increase in cooling capacity for the -3.
Though Packard didn't make them, I wonder how a Merlin 45 would have gone in the P-39. Obviously low down performance would suffer, but there should be some gain at higher altitudes (the 45 having a higher FTH than the Allison).
Actually not by that much once the later Allisons with 9.60 gears showed up. Critical height the Merlin 45 may be 3-4,000ft higher than a late model P-39 which would be a help but not solve the problem. The Late Allisons sort of split the difference between an early Allison and the Merlin 45.
A big problem is the weight, A P-39D clean is about 1000lbs heavier than a Spit V clean or almost 15%. Put together with the smaller wing and the wing loading was about 30% higher. At altitude the P-39 has to fly faster just to keep from stalling leaving that much less power for climb and maneuver.
Then you have a take-off problem. Early P-39s had 1150hp for take-off, late model Ds, Ks and Ls had 1325hp for take-off and the late versions had 1200hp for take-off. Merlin 45 had 1230hp for take-off at 12 lb boost. While the Allison was rated for 5 minutes CLIMBING at take-off or Military Power the Merlin was not so rated, what they did in the squadrons I don't know. We do know that Allisons tolerated over-boost abuse fairly well at low altitudes.
The main problem to get V-1650-1 in P-39 would've been the low availability; also, IIRC the reduction gear was integral with crankcase - not compatible with P-39 power-plant installation.
The table for the V-1650-1 lists the critical altitudes in the wrong column, under 'with ram', instead under 'no ram'.
Some US pilots were able to engage the Japanese at altitudes where the P-39 was able to put up a fight. "Buzz" Wagner was one of the first US aces and scrored kills in both P-40 and P-39. He led several low level raids that were quite successful before being sent back to the US with 8 credits. He was later killed in a P-40 crash stateside.
Pittsburgh Post-Gazette - Google News Archive Search
There's more than a little doubt about the 3 kills attributed to Wagner on that mission.
Duane
Do you have any details? Could you please explain what the other side of the story is?
There's more than a little doubt about the 3 kills attributed to Wagner on that mission.
Duane
Would you have a source that has the correct information?
Bottom line, Wagner and his pilots successfully brought the fight to the Japanese and did show the P-39 could at least hold its own uncer the right circumstances.
We could also re-write history and take 3 credits away from one of the first US Aces...
I don't think that history needs to be rewritten and I'm not saying for certain that he didn't shoot down the 3 Zeros. But it remains a controversial topic as noted in the 8th Fighter Groups history Attack and Conquer. Nevertheless The Air Force
and the American Aces Association both credit him with 8 victories which includes the 3 from the Lae Mission. But, it's no secret that alot of the stories that came out of the Pacific during the first 6 months of the war were pure propaganda. Witness the variety of stories about Colin Kelly. When the legend becomes fact, print the legend. As far as the merits of the P-39 vs. the Zero goes, Wagner's written report on it after the Lae mission is very informative.
Duane
Down on the deck, one on one with a Zero, what would you guys want to be in, a P39, an F4F or a P40? Personally, I would take the P39 because it is alot faster and has a very good climb rate down low. Of course, hind sight 20/20, I would also want all the wing guns removed to dump a few hundred pounds of extra weight and I would want the 20mm cannon and not the 37mm cannon.
Pinsog, I have noticed the same thing - the charts show the P-39 as faster than the F4F to 24,000 feet, and if we overlaid a A6M-2 chart, the P-39 would likely have a similar paper advantage over the Zero. So why did the P-39 have the reputation of being such a dog at much lower altitudes, sometimes 12,000 to 15,000 feet? I can understand that the Guadalcanal P-400s didn't have oxygen. That's a good excuse, but the New Guinea P-39s had the reputation of being dogs both to the American and the Japanese pilots, and they were U.S. spec.