P-39 Expert
Non-Expert
None of the Allison powered fighters, nor the P-47 nor the Spitfire V met hot day cooling standards.
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From lightest to heaviest the weight difference is 4.1% and yet the lightest plane (the N) shows a best climb of 380fpm (10% over the next best and even more over the rest.
There was actually a second climb test on that same P-39N #4400 about a month later on November 24 to record WEP climb which was not used on the original P-39N climb test. This climb test showed the expected increase in climb below critical altitude but the climb rate at 15000' (critical altitude for climb) was 3230fpm or only 110fpm lower than the previous test at the same 1060HP. Weight was only 27# more. The climb rate at 15000' was virtually the same on both tests, indicating neither test was a fluke and the plane climbed as advertised. Climbed faster than just about anything in '43 except a Spitfire IX.I would respect it a lot more if the tests for the aircraft preceding it, which used the same engine but a different prop and the planes that followed it which used the same engines but different props on some, were anywhere near it. of these five airplanes/tests/charts the weight of the aircraft varies by 400lbs form lightest to heaviest. From lightest to heaviest the weight difference is 4.1% and yet the lightest plane (the N) shows a best climb of 380fpm (10% over the next best and even more over the rest. The other four aircraft show weight variation of about 200lbs and yet the climb difference is barely over 100fpm. The two late model Qs have no guns in or under the wings and would have less drag than the N even if a few hundred pounds heavier. Even a test of the P-39Q-5 at 7871lbs (6th test) with no wing guns shows only a 200-300fpm fall off in climb even with an engine not quite making full power (55in) at 3600-3700fpm.
So if you have 5 out 6 planes closely clustered in weight and using the same power engine and closely clustered in climb and the 6th plane using the same engine and only slightly less weight showing a major increase in climb rate what are you to believe?
What guarantee do you have that a plane 5 or 10 serial numbers different than the test plane is going to act like the test plane or act like the other 5 planes tested?
Maybe this can clear up the debate on just how good the P-39 really was when used correctly. You'll need to run this in google chrome for it to automatically translate.Great information guys. Thank you all.
Am I going crazy or did that article repeat itself w few times in the body of text?Maybe this can clear up the debate on just how good the P-39 really was when used correctly. You'll need to run this in google chrome for it to automatically translate.
P-39 Аэрокобра на советско-германском фронте
But, I could still be crazy.you are not crazy. More than few times.
You might like to try going through the entire website. There's a lot more detail in the P-40 section. IIRC there's a section on fighter tactics somewhere but its a long while ago that I found all this. IIRC, the Cobras used to fly in four pairs of two separated by 1000 feet of height with only two assigned the task of shooters, the rest acting as cover. It was called group area fighting tactics.It is interesting but flawed, it doesn't really say how the planes were were used (tactics or combat situation) and relies on the rather dubious method of comparing the scores of the top aces. I am not trying to get into an argument about claiming or over claiming or anything like that.
The method is dubious because it fails to take into account the number of missions flown by the pilots of each type and number of times each pilot was actually engaged in combat. As an extreme example we have Eric Hartman who (according to wiki) He "flew 1,404 combat missions and participated in aerial combat on 825 separate occasions." to get is 352 victories.
This article does not tell us how many combat missions the various pilots (of several air forces) flew or how many of those missions resulted in actual combat.
The US in particular tended to rotate pilots out of combat after a fixed number of missions (although many extended their tours voluntarily or signed up up for a whole new tour, same with many British pilots, including the commonwealth).
So if you have a Russian pilot who flew plane A on 250 missions and engaged in combat (fired guns?) 175 times and claimed 50 victories how does that prove that Plane A was better than Plane B that was flown by An american pilot 120 times and fired it's guns 75 times and shot down 30 planes? (made up numbers)
Please note I am not trying to take anything away for Hartman or any of the pilots listed in the article. In many cases it was a testament to luck, skill and day in day out courage simply to survive 100 mission let alone several hundred. Shooting down substantial quantities of enemy aircraft is a whole different story.
Maybe this can clear up the debate on just how good the P-39 really was when used correctly. You'll need to run this in google chrome for it to automatically translate.
P-39 Аэрокобра на советско-германском фронте
It appears to me that the P-39 appeared to do well in Soviet service because their standards tended to be much lower than those of the Western Allies.
- Ivan.
Ivan, in a way you are correct. The Russians did not have the natural resources
available to them as many other nations had. Most of there aircraft exteriors
were wood and the engines available to them early in the war were very limited
in power.
If by lower you mean geared to the lower altitudes then you are absolutely
correct. If you mean their expectation of what they wanted out of there front
line fighters then I would reply, " No, I do not believe any of the warring nations
wished to settle for less than the nation's aircraft they had to oppose."
Hello!
I was intrigued by reading of this interview with Golodnikov, especially by his mention about true performances of German fighters (color plus some correction of the text by me):
"A. S. Nikolay Gerasimovich, if you look at any reference book, the superiority in speed of German aircraft [like] the Bf-109G and FW-190 is indisputable. Minimum 20-25 kilometers at low altitudes and up to 80-100 kilometers at high altitudes. And you say ours did not lag behind?
N. G. No, some difference in speed always exists. At low altitudes we were a bit faster, at high altitudes they were. The difference was on the order of 10-20 km. But this difference was not so great that it ensured overwhelming superiority. In combat it was practically not discernible.
A. S. Nikolay Gerasimovich, sometime relatively long ago I was speaking with a pilot, a frontline veteran. Right after the war they flew in captured aircraft. And no matter how hard they tried, they were unable to attain the speeds the Germans had written in their specifications. The shortfall in speed was significant. In the end, they prevailed upon a German, a high-level specialist, and asked him, "Why this shortfall in speed? Are we using the engine's capability incorrectly?" His response was that they would never achieve the target speed, because the German specifications showed the theoretical speed, and they were attempting to attain that speed on their instruments.
Nikolay Gerasimovich, in your view, is this possible?
N. G. Of course. We had a group of specialists with us from NII VVS. They were examining specifications and were looking at speed. "What speed is indicated at 7,000 meters? 780? Take away 100. And what about 3,000 meters? 700? Reduce it 70 km." This is how they calculated the instrumented speed and, characteristically, almost always hit their target. Perhaps they knew something about our focus on speed."
I wonder what they mean for "theoretical speed": didn't Germans actually test in flight their planes? And what is this "instrument speed" they speak of?
I would be glad to know your opinion. Cheers,
GB
P-39 actually held lots of fuel when compared to European planes. More than the Spitfire and Me109 and more than a Fw190 based on gallons to displacement.
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