P-39 vs P-40

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Very rough translation, but sense is such:

At 1 May in PVO regiments are 51 P-63s.
At first Kingkobras received 28th rgt PVO near Moscow.
At August 17th and 821st regiments PVO received 10 planes each.
Autumn 1944 (it seems a mistake, probably 1945) a few planes received 39 IAP in Malino (near Moscow).

Summer VVS started rearmament. Priority had Air Forces at Far East.
They altered the route ALSIB, form Markovo to Petropavlovsk-Kamchatsky, and from Krasnoyarsk route to led off through Chita to Ukkurey (Ukkurey - Wikipedia, the free encyclopedia) for rearmament of 12th Air Force.
By first, apparently, P-63 equipped 190th division of the Major General V.V. Fokin, which was relocated in Transbaykal in June 1945 Since June 24 it began to obtain "Kingcobras" and by August 2 finished retraining. During the combat operations in Manchuria it flew from two airfields - "Ural" and "Leningrad under city Choibalsan in the Mongolia. After war this division a certain time stood under Ulan-Ude.
There, in the 12th air force at the Transbaikal Front fighted the 245th division, in composition of which were two regiments (940th and 781st), that flew on P-63. In July-August the first of "Kingcobras" they entered in 128th the mixed division, which was being based himself on Kamchatka. P-63 arrived into the 9th and 10th air forces too. For them they lenghten route to Khabarovsk. Here at the beginning military operations it was saved by 97 P-63, which did not have time to give on the regiments.
 
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Next fragment:

At this time first P-63 entered into the 7th fighter division VVS of Pacific Ocean fleet. By August 9, when started war with Japan, division had 10 "Kingcobras". About twenty arrived already in the course of military operations, until August 31. They assumed no participation in the operations against the Japanese.
 
What year was this?
I have a record of one Kingcobra being destroyed by the Japanese among 62 (if I recall) of all Soviet types destroyed, at the end of hostilities when the Soviets exploited Japan's exhaustion at the close of WWII to take Sakhalin.
 
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Now we are getting somewhere with this P-63 puzzle.

Back at #64 of this thread I posted this:

"The Soviet air cover and support for the Shimushu landings were provided by the 128 SAD, their 888 IAP had the P-63 Kingcobra, which they had received only in August 1945, before that they remained the last active Soviet fighter regiment with the I-16."

The recent translated material seems to mesh with this timeline. August Storm was obviously well-and-long thought out by the General Staff -- executed flawlessly.

But I am struck by the LATE DATE conversion of the last I-16 unit to P-63's as part of the August Storm build up. What that tells me is the QUALITY of fighters that the Soviets could get away with in the Far East from 1941 to '45. Much the same as the USAAF using P-39's in the Panama Canal Zone

MM
 
Have been reading WARPLANES TO ALASKA by Blake W. Smith and found a couple interesting things. It was a Soviet, General L.G. Rudenko, who requested that all aircraft deliveries of the 4th Protocol of Lend-Lease (which included all P63s), be done by the Alaska-Siberia route, rather than through Iran. Had the Soviets wished to use P63s against Germany, it would have been much simpler to bring them in through Iran.
Also, a quote from page 197:
 
Going by "Vee's for Victory" by Daniel Whitney there were several reasons for deleting the Turbo from the P-39. Not the least of which seems to be that with the original installation the Airplane couldn't come close to the performance estimites or guarantees. Bell was off by about 10% on the weight of the UNARMED plane and off by at least that much in the speed. The intercooler installation seems to have been really bad. It not only had high drag but didn't work very well. In the interest of light weight it had been kept small but the result was that it didn't cool the intake charge very well. While most American intercoolers tried to remove 50% of the heat of compression between the two stages the XP-39 was only managing about 25% during high speed flight and 12% during climb. This ment much more danger of detonation and ment that full power or boost could not be used thus limiting performance of the aircraft. NACA estimated after installing the XP-39 in their full sized windtunnel that a single stage "altitude rated" engine would provide about 30mph more speed than the turbo engine up to about 13-14,000ft. This is after NACA did a clean-up that added 40+mph to the speed of the plane. the Turbo version wasn't expected to show ANY advantage in speed until over 19,000ft had been reached. And it was still about 10mph below the Guarantee speed. Once the requirement changed from 400mph at 20,000ft to 400mph at 15,000 the turbo was really out of the running. The small size of the P-39 ment that installing a larger intercooler setup was almost out of the question.
Please remember that the Early P-38s used the leading edges of the outer wings as inter-coolers and that some models of the P-38 had difficulty in using full power because while these leading edge intercoolers worked well enough with 1150HP engines they were not big enough to handle the airflow of 1300-1425HP engines.
 
Yeager said he could beat anybody in a P 39 at 100 feet. But no one wanted to fight at that altitude.

winkle brown flew both the F 4f and the hurricane.
How did they compare?
 
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Excellent post - thank you.
This helps clear up lingering questions, and dispel much hearsay, about why the turbo was removed from the P-39.

Any insights on why, after these changes were made and the plane fielded, the P-39 was so hated by the Americans but loved by the Soviets?

As this post started, the P-39 P-40 both had single-stage supercharged Allison V-1710's.
Did the P-39 really underperform compared to the P-39?
 
According to Wikipedia (take with a grain of salt)

P-39Q
empty weight 5,347 lbs
loaded weight 7,379 lbs
max takeoff weight 8,400 lbs

P-40E
empty weight 6,352 lbs
loaded weight 8,280 lbs
max takeoff weight 8,810 lbs

If they had same or similar engines, then it seems the P-39 should perform well.
 
gjs238 said:
...
Any insights on why, after these changes were made and the plane fielded, the P-39 was so hated by the Americans but loved by the Soviets?
Click to expand...

P-39 was the perhaps the fastest VVS airplane from 1942-44, featuring a good punch, dependable radio, final finish was much better that of Soviet planes, it's combat range was comparable with other planes. So they have had reasons to love it
USAAC was fighting on greater ranges, and it was encountering JAAF/IJN bombers in high altitudes, and P-39 was hardly an answer for such tasks.

As this post started, the P-39 P-40 both had single-stage supercharged Allison V-1710's.
Did the P-39 really underperform compared to the P-39?
Click to expand...

P-39 was batter than P-39
Jokes aside, P-39 provided slightly better performance figures than P-40 with similar engine.
 
Just a few comments on this excellent thread.

Turbo was deleted from the P-39 in order to get it into production faster. Contemporary P-38 did not enter combat until Dec '42. P-39D was in production in late '41. Notwithstanding, the turbo instal in the P-39 would never work dependably, radiator ducts (coolant, oil and intercooler) were not adjustable meaning too much air at low power and not enough at high power. Also Allison promised more HP was coming with higher supercharger ratios or a mechanical second stage so turbo was deleted.

When comparing the P-39 and P-40 please remember the P-40 was substantially heavier (7650 vs 8400) so with the same engine and propeller the P-39 was faster and much better climb/ceiling. No way out of it.

Russian P-39s performed better because they were lighter than western P-39s because they deleted the 4x.30caliber MGs in the wings and the IFF radio. They thought the light .30caliber MGs were worthless and plenty firepower was left with the 37mm cannon and 2x.50caliber MGs. Saved about 300# (200# for .30caliberMGs and 100# for IFF radio). Russians lightened the P-40 also by deleting 2 of the 6 .50caliber MGs.

Eastern front was fought at lower altitudes than western front (no turbocharged B-17s and B-24s) but that does not explain the P-39s success in that theater. P-39N/Q was competitive with the Luftwaffe at all altitudes or they could not have had the success they had. Altitude was everything in WWII, without it you were a dead duck.

A chart from wwiiaircraftperformance showing speeds for P-39N and P-40N is attached for reference.
 
The P-40N in the above graph is the untralight early N that only weighed 7600# and reverted to the normal weight for production. So production P-40Ns would be slower than this one.
 
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