I'm researching a P-39 accident where the .50 cal guns shot off the propeller of the P-39 causing it to crash because they were out of synchronization. Do you know of any documented problems with the synchronized Browning .50 in the P-39?
Anonymous, 04.06.2022 01:17
"In British service the Airacobra I/IA was used for a short time for ground attack duties. It was not well received and production aircraft completed for Britain, but undelivered, were taken on by the USAAF as trainers." Actually, they were shipped to the South Pacific and used as operational fighters by the USAAF under the designation "P-400". Apparently, they were not very well-liked. American USAAF fighter pilots quipped that "a P-400 was a P-39 with a Zero on its' tail".
Doug Barylski, e-mail, 08.06.2020 01:45
A modified P-39 won the Thompson Trophy in 1946 or 47.
Doug Barylski, e-mail, 08.06.2020 01:42
An old post, but in case no one got bak to you, the answer is yes. Look up Thompson Trophy. P-39 won it one year, maybe 1947.
Doug Barylski, e-mail, 06.06.2020 15:54
Hello, The aircraft at the Kalamazoo Air Zoo is a P-39 painted to appear as the P-400 flown by Zed Fountain at Guadalcanal, but it is not the actual aircraft. Unfortunately, the only actual aircraft are a couple of wrecks unearthed in the 1970's, both of which are still there. I am researching the aircraft flown by these first pilots at Guadalcanal, so it is great to know about "Whistlin Britches". Could you please reply back and tell me if you can verify the serial number BW146 and aircraft number 20 on the tail? Thank you, Doug B.
ron, e-mail, 12.11.2017 02:24
The 37mm M4 cannon could be recharged once in flight if it jammed. Russian pilots say this was enough. They did not think it was unreliable if properly maintained. They found the western lubrication for the P-400 Cobra and it's 20mm M2 cannon would freeze too easily.
ron, e-mail, 14.10.2017 10:18
The P-400 was originally RAF so these Cobras had the Hispano 20mm instead of the M4 37mm. I would consider the Hispano Mk V to be a contemporary to the B-20. Not as light but more so than the former Hispanos. It was between them and the B-20 in RoF. It had the heavy hitting shell that the B-20 lacked. The P-63 should've taken a cue from the P-400 and offered a 20mm option with this RAF Hispano in place of the 37mm cannon. I don't believe the VVS would want to replace it like they did the M2 Hispano cannon of the P-400. It may have given the USAAC pause as well. The ballistics would certainly be more harmonized. Why let the Tempest be the only beneficiary of this refined Hispano cannon that worked so well, when they could have the Kingcobra packing it in US colors?
Now back to the VVS. The 20mm Russian shells were too light for many pilots. As for the 23mm cannons, the VYa-23 jammed. The later NS-23 had pedestrian M/V.
In fact, the Hispano Mk V may have been the best WW2 20mm cannon. The Type 99-II Mk 5 was it's near equal, but only a handful of J2M5b interceptors had it for sure.
The powerful MG 151/20 is close but aside from the mineshells, it was like the ShVAK or Ho-5 in modest punch. The cannon wing-boots on the Bf 109 had mineshells among the ammo belt shell composition, but not every MG 151/20 cannon had them. The Ho-5 was fastest but downloaded to 600m range in 1945 for lack of rare metals. The RAF Hispano Mk II was too heavy and slow in this crowd. The US Hispano was also, and jammed too much besides. That goes for all US WW2 models, M1, M2, M3.
This leaves the RAF Mk V smelling sweet. If anything could tip the balance for Bell in US service, it would be this cannon. A second chance for a reborn P-400.
The Mk V was the best WW2 Hispano. It had no faults.
ron, e-mail, 13.10.2017 05:03
The 97kg M4 jams and has short 460m range. The 29kg Browning M2 12.7mm is the slowest cowl gun. The P-39 is prone to spin when nose-ammo is spent. Nose-guns weigh 155kg. With the 43-51kg 20mm Hispano M1 jams too but range was 900-1500m. 101-109kg total weight for the P-400 nose-guns.
The 21.5kg UBS is the fastest cowl-gun +the 25kg B-20. Nose-guns replacements weigh only 68kg total! They don't jam and range is good but the B-20 shell is lighter than the that of the Hispano. But the 12.7mm UBS shell is heavier than the that of the Browning 0.50 Cal.
How to improve the spin tendency with the ammo load spent? You could say the weight difference between full ammo and empty was a problem for the trim. My opinion is the 37mm P-39 had the heaviest ammo loadout and the B-20 cannon, the least. The 178kg NS-37 had 735g shells so spin may not be helped enough.
The 23mm would be between them with the Hispano. The NS-23 is my fantasy choice, since many pilots felt the 20mm Russian shells were not heavy enough vs the Hispano, MG/FF, Ho-3 or Type 99. The 68kg 23mm VYa cannon jammed at times. Since the B-20 was the 20mm ShVAK replacement, my choice is the more reliable 37kg NS-23 replacement for the VYa-23. In the case of the P-63, I would look for more than 1x23 and 2x12.7mm guns. 3x23mm cannons! Three NS-23 cannons total 111kg. The twins in the cowl could be moved to the sides of the cockpit to put their ammo a bit behind the cg to offset the hub-cannon ammo. Longer barrels would only help firing range which was only about 750m (the VYa-23 range was double that). But this is all just academic hindsight. Interesting nonetheless.
ron, e-mail, 13.10.2017 01:24
"When the original US-built armament became unserviceable, it was replaced by the Soviet 20-mm B-20 cannon and the 12.7mm Berezin UBS machine guns." - Baugher's site on P-39s.
From the slowest 12.7mm gun in WW2 to one of the fastest. From the heaviest 20mm cannon (P-400) to the lightest; 25kg! The USAAFC should've acquired some reliable B-20 cannons and copied them to install in all our planes. The Browning M2 0.50 Cal (12.7mm) weighed more!
The Cobra must've been more effective with the Russian guns. Perhaps that was part of the Cobra's success in Russia. The sightings of P-63s in combat against the Luftwaffe have no Russian recorded evidence, officially. Only in personal diaries of Soviet aces. Shhh! Anyway, If I were such an ace, I would pack my 'P-39' with a trio of B-20s in the nose. Maybe even NS-23s! They only weigh 37kg but hit with a 175g shell at the same rate as a 20mm M2 Hispano cannon: 600 r/m! The US 37mm M4 and M10 were not much more reliable than the US Hispano.
ron, e-mail, 22.07.2017 04:27
The P-400 Cobra reportedly had the RAF 20mm Mk 1 Hispano cannon, so it was more reliable than the 20mm US Hispano cannon in the P-38 Lightning.
raoul, e-mail, 31.08.2016 22:02
RE: P-39 in air races.
In one of my books, there is a P-39 painted up with race numbers and sponsor signs. So, at least one was used in an air race. There was no information about its success (or lack thereof). Since it was postwar and undoubtedly a war vet, it might have been picked up for cheap, stripped down of anything that was not essential for flying (Guns, armor, etc.) and then raced. Surprising how many "worst airplane of all time" books contain entries for the 39 and 63. Far from being the worst and pretty darn good in the application where it was used. Not the use it was designed for but there are a lot of Russian pilots who were glad to have it.
ron, e-mail, 17.02.2016 00:53
460m was the firing range of the 37mm M4
Klaatu83, e-mail, 26.03.2015 04:58
The original XP-39 prototype had a turbo-supercharger and exceeded 400 mph, but the Army Air Corps insisted that the supercharger be deleted from the production version. At the same time the AAC also specified additional armament and armor, which increased weight. As a result, the production versions never performed as well as the prototype.
mark, e-mail, 19.02.2015 21:54
George Mellinger and John Stanaway, several pilots stated that the main reason to the mediocre performance on Pacific was the engine and that with decent supercharger to provide decent altitude performance, it would have been better than Mitsubishi A6M Reisen, Zero. The aeroplane itself was a sound construction except the alleged tendency to flat spin, which all pilots did not subscribe their experience referring more to slow controllable oscillation. The mediocre supercharger stemmed from doctrine that there was no real need for high altitude performance over US continent due to lack of potentially capable bombers.
Klaatu83, e-mail, 14.11.2014 06:18
"Wasn't the nick name "pinball"?"
The nickname "pinball" was applied to certain P-63s that were specially equipped to serve as gunnery targets for use in training air gunners. The gunners shot at the P-63s with special frangible ammo, and the P-63s were equipped with additional armor protection and special set of lights that were designed to light up whenever a hit was registered.
Ron, e-mail, 19.09.2014 05:09
If anyone still falls for the myth that the Russians used the P-39 for tank-busting primarily, just remember the words of the top P-39 pilot, Pokryshkin. His Russian T-34 tank buddies asked him to bust the Nazi tanks, he replied that his P-39s can't penetrate tank armor. Their Olds M4 37mm hub cannon has only a muzzle velocity of 600 mps vs 900 mps for the Soviet NS-37 in the Yak-9T fighter, wth a throw-weight of 141 gps vs 306 gps.
P-39s were used for air superiority by Russia, primarily. The Yak-9K was for tank-busting with it's 45mm cannon (unfortunately the recoil caused engine leaks in the Yak so it didn't just hurt the Panzers).
That's why the elite Red Guards flew Cobras against the Luftwaffe (P-63s too but thats off the official record).
The Cobra's M4 37mm was very effective against Nazi bombers as well as fighters.
Don't tell anybody about the P-63s used on the Eastern front. On paper they were still officially 'P-39s' (to abide by lend-lease rules to be used against Japan only). But the German pilots that were shot down by King Cobras knew the difference between P-39s and P-63s!
That P-63s didn't fight Germany is another myth but we won't tell. If you were a Russian ace, could you be blamed if you covertly arranged to fly a new P-63 instead of a left over P-39 when you're fighting for your life against the latest from Kurt Tank and Messerschmitt! As long as it was recorded as a 'P-39' on the official flight log. Otherwise thousands of P-63s are just sitting on the tarmac collecting dust waiting till the last Russian offensive against Japan in the of summer, 1945.
Ron, e-mail, 19.08.2014 01:26
Russian pilots thought the P-39 was better around 15,000' using climb and dive, while the P-40 was better lower using horizontal tactics. The spin recovery for the Cobra was dicey.
Ron, e-mail, 07.07.2014 21:27
The RoF for the Browning 0.30 Cal of 1200 was actually more like a dissappointing 840 rpm. However, the synchronized rate was about 730 rpm. Bench tests don't have the idiosyncracies of drive or priming and propeller variations. Constant speed propellers, and prop drive help as does electric firing if reliable of course.
So, the P-39 had another reason to lose the disappointing '1200 rpm' light wing guns. Only the Zero would be affected by them after mid-war.
The data published can be less than reliable which doesn't help research much.
Ron, e-mail, 06.07.2014 05:16
The dicrepency between the P-39's .50 Cal. Browning ROF nose gun and others US fighters synchronized ROF was in the P-39's reduction gear driven design unlike the prop drive sync design. The F2A even had electric firing of the synchronized MGs like the Luftwaffe but slower. That's why the 300 rpm for the P-39 is worse than about 37% reduction for the synchronized Browning .50 typically (Brittish bench tests). Curiously the Browning .30 Cal. had only a 13% reduction which is closer to non-Browning sync. ROF. The P-39 was unfortunately the slowest at only 5 rps each gun in the cowl. Others got perhaps 425 rpm for the Browning .50 Cal. cowl gun. Even better for the Buffalo.
Richard, e-mail, 26.12.2013 22:22
Wasn't the nick name "pinball"? My dad flew the 39 and 63 to the Russians. All the pilots that picked them up where women, with Vodka. He and 17 other men associated with the program were flown to Magadan from Anchorage to celebrate the 60th anniversary of the war ending. He loved both of the planes. He had a lot of photos of the Bell's sitting on the line waiting for delivery with the Red Star's. He told me a story of someone writing TEXACO on one of the stars and what a mess that turned out to be. The Ruskies didn't find it funny.
Richard Kennedy, e-mail, 04.12.2013 17:14
Not a comment but a question, "Was the P-39 ever used as a Racer in speed flying?
neil rose, e-mail, 09.04.2013 03:44
I am currently planning on rebuilding a P39Q....am long in the tooth but think I can make it. Last airplanes I rebuilt were a Pv2 and a Hawker Hurricne...yup I flew both of them..If someone were to give me a derlict Hurricene I would run the other way.. actually I still have the data plate and paper work for one... but it will never be rebuilt by me...Figure the Cobra will be a picen of cake.. Any one with parts pices etc.would like to hear from you. Had an aquaintence who flew cobras...one day I asked him "in all the wrecks you witnessed which way did the engine go ...Just as Bell convinced us it always went out the side" "the biggest worry was the driveline coming loose and beating our balls... So said Capt Bob Darling USAAC
Klaatu83, e-mail, 16.09.2012 17:19
"production aircraft completed for Britain, but undelivered, were taken on by the USAAF as trainers."
In fact, the USAAF used these aircraft operationally in New Guinea, where the type was known as the "P-400".
These aircraft were not well received by the RAF because the export versions lacked supercharged engines for good high-altitude performance, the unfamiliar car-type doors, the mixed-caliber armament, and the fact that the tricycle landing gear did not lend itself well operation from the RAF's grass airstrips.
Chris, e-mail, 17.07.2012 22:14
The P-39 "Whistlin Britches " was flown by my great uncle Lt. Zed Fountain. The aircraft is currently in the Kalamazoo Air Zoo in Michigan. It was named after an old man who use to walk up and down his street whistling all the time.
Jim Jenkins, e-mail, 05.05.2012 18:58
Does anyone have pictures of P39 training at Harris Neck, Ga?
Phil, e-mail, 02.02.2012 17:45
I saw the first takeoff of the P-39 as a youth in 1939. It was in Dayton, Ohio at (I believe) Patterson Field, the predecessor of Wright-Patterson Field.
Hal, e-mail, 27.06.2011 23:04
Eaglefeather, you are absolutely correct on the weight. Also,Soviet pilots were generally more experienced than their American counterparts in mid-1942 having been in combat with the Luftwaffe for a year. Mid-'42 was the first air combat for the Army Air Force, virtually all the flyers in New Guinea being brand new 200 hour pilots fresh out of flying school.
Aaron, e-mail, 25.06.2011 20:08
I'm going to shoot from the hip with some actual vs calculated knowledge and educated SWAGing. The reason the P-39 was so popular with VVS pilots was that the USSR versions were lightened. Wing guns came off and equipment that they deemed superfluous was removed. These changes enhanced the performance considerably. Coupled with the fact that they boosted the early Allison engines to 66" and even 70" in some cases. They boosted the later versions of Allisons to 57" when they could get U.S. fuel. This jumped horse power as much as 500 ponies. The figures I posted earlier for the P-39N reaching 397mph and 399mph were from U.S. military and factory documents. Now amagine what these figures would be if the plane was 500 lbs. lighter and had 500 more horses kicking it around the sky. I haven't seen any documents that say so,,,,,,YET, but it wouldn't supprise me if the Russian pilots had pushed their N and Q models to 410mph+ at 13,000ft. and pushed maximum climb to over 4,600fpm. Just something to think about. Now I,m heading over to the USSR sight to post some facts on the Lavochkin fighters. Hopefully get to the Yakovlev sight in the near future also.
Hal, e-mail, 10.06.2011 18:54
Hmmm, 14,500 Yak-9s built during WWII, less than 5,000 P-39s sent to Russia. Yet three of the top 4 Russian aces flew the P-39, and 40 more aces with 20+ victories. I'll take the P-39, thanks.
steve, e-mail, 10.06.2011 00:23
About midway through the war, the Russians built their own equivalent, the Yak-9T. With an engine designed to use a hub gun (the M-105, derived from the Hispano-Suiza 12Y) it not surprisingly turned out rather better. Although intended for ground attack, the Yak-9T was quite successful in air combat as well. The 37mm gun was more powerful and had a higher rate of fire than the P-39's M-4. It would reward a good shot with the discipline to fire the necessarily short (2-3 rounds) burst before the recoil knocked the aim off target. See Yefim Gordon's book on Russian WWII fighters.
Hal, e-mail, 12.05.2011 01:01
Some P-39Qs in the dash 20-25 range had four blade propellers as standard factory equipment.
Regarding the supercharger, turbochargers were not yet reliable when the P-39 (and P-40) was in prototype stage, and the installation in the P-39 was less than optimal. In short the turbo was never going to work properly in the P-39 and America needed fighter planes desperately in 1941 so the turbo was deleted to get the P-39 (and P-40)into production. The P-39N which was first delivered in December 1942 was the equal of the FW190 and Me109G6 in all performance categories according to Soviet pilots in books released since the fall of the old Soviet Union. The Russians did get substantial extra performance by deleting the useless 30 caliber wing guns and some radio equipment.
While the turbocharger was doomed from the beginning in the P-39, Allison had developed a second stage mechanical supercharger that later powered the P-63 Kingcobra to 422mph at 25,000', comparable to P-47s and P-51s. This mechanical supercharger was tested in the P-39E and did produce higher top speed, but the P-39E was way to heavy for a production contract and served as testbed for the new supercharger to be installed in the P-63. I have never figured out why the AAF didn't just install one in a standard P-39. It would fit and the P-39 would have had P-63 performance in mid 1942 instead of late 1943 when the P-63 started production.
Aaron, e-mail, 17.04.2011 21:22
Ken, Brad is probably right. The P-39Q-21/25 had four blade props but I do not know if any of that version are still flying.
XWXwireXWX, e-mail, 17.04.2011 06:11
This craft was way underused by the US. It had some of the best potential that we have thrown away. Keeping it operational would have given America a close-support/ground attack/bomber destroyer (Big Russian factor) to rival the Hawker Typhoon/Tempest series. The Kingcobra would have been a huge advance over the Airacobra, but production and design was slowed because of the rejection given to the latter.
Brad, e-mail, 28.03.2011 05:02
The plane you saw was probably the follow-on version called the P-63 King Cobra. It had the 4 bladed Aeroproducts propeller
Jim Loosen, e-mail, 25.03.2011 20:15
Note to Ken.... I flew P-39Qs and Ns back in 1944 out of Las Vegas Army Air Field. We were flying attack patterns against 3-ship B-17 formations, loaded with gunnery students. At that time I do not recall seeing even one P-39 with other than a 3-bladed prop. I think the Red Star P-39 you saw belongs to the Commemorative Air force, and is based in Texas.
Ken, e-mail, 14.03.2011 22:22
Hey guys, This weekend I saw what I determined was a Bell P39 with the Russian red star. The only thing that I can't sseem to match is that this aircraft had a 4 blade prop. Was this a configuration of later (or earlier) models?
Ben Beekman, e-mail, 01.03.2011 03:35
There seems to be quite a bit of controversy as to why this otherwise excellent aircraft was denied a supercharger. I wonder if supercharger technology was something that the president and his military advisors decided to keep from the Russians. If the Soviets had a U.S. built supercharger to examine they might be able to reverse engineer it and start building their own as they did with the damaged B-29's that landed in Russia after bombing Japan.
Allard's ally mickey, e-mail, 11.02.2011 02:05
I have an interest in one particular P-39, one of the first over Guadalcanal, named "Whistlin'Britches" #66,based in New Guinea flown by col. Charles Allard + two or three other pilots. It was last seen when Col. Allard brought it back as a recruitment tour showpiece but he fell ill with malaria and when he was released the tour, and the plane, were "decommissioned". The plane had dissappeared. I had some personal phone and mail correspondence with Allard some years ago but lost touch and doubt he is still living. He made it his "project" to to find the plane but all I have heard is he was only able to find a similar plane now in a museum and painted in Pacific theater markings somewhere in an air museum in the Midwest??? Anyone care to comment
Don Green, e-mail, 19.11.2010 08:22
Flew the "D" model many hundreds of hours..Dependable..37 cannon no good..got the Aussie version with 20 mm cannon and it performed reasonably well but no altitude capability..our entire squadron of 39's was lost in two months(New Guinea)..thirteen pilots shot down..some trwice..including me..for it's time not so bad..P-38's replaced the 39 and changed the complextion of the Pacific air war..
Aaron, e-mail, 22.10.2010 02:27
Consolidated moved to San Diago in 1935. Laurence Dale Bell, Robert J. Woods and Ray Whitman stayed in Buffalo and formed Bell Aircraft. The plant at 2050 Elmood Ave. in Buffalo, NY. was built shortly after. The first military aircraft built at this plant was the XFM-1 Airacuda in 1937. In 1938 they began manufacturing the P-39. Larry Bell was an excellent salesman. In 1913 he was working for Martin. Bell convinced Martin to put on an exhibition that he called "THE BATTLE OF THE CLOUDS". The show included a parachute jump, balloons and exhibition flying, but the main attraction was the aerial bombing of a make-believe battlefield-complete with a fort, cannon and soldiers. Bell wanted to give the crowd its money's worth. Martin flew over the painted cloth and wood fort, throwing out oranges, while Bell set off dynamite charges on the ground. Martin Company employees, armed with rifles, fired off blank cartridges. The cannon also made of cloth and wood, caught fire, and as bell set off his last charges and ran for cover, the entire battlefield went up in flames. Two interested spectators sought out Bell and Martin as they counted the day's receipts. Pedro and Juan Alcaldez were representatives of Pancho Villa. At a cost of $10,000 Bell and Martin built the world's first combat bomber for "Pancho Villa's Air Force".
Aaron, e-mail, 17.10.2010 19:45
Ray Wagner, in his books, list the performance of the P-39N with the V-1710-85 (1,420hp/9,000ft. WE)as such: Max speed: 399mph/9700ft. 15,000ft/3.8min.(3947fpm/avg.) Service Ceiling: 36.500ft. Maximum range (ferry):1,250mls. This at a test weight of 7,400lbs. These figures are very close to the test figures I posted earlier and well within the norm of aircraft to aircraft variances.
readreader, e-mail, 17.10.2010 00:18
I really like the p - 39 and the King Cobra also I have heard the octane in the gas was very important on the allison and merlin engines. I dont understand why the three stage turb charger wasnt given on the p - 39 which would hve made it comparible to all the 40`s fighters.
Aaron, e-mail, 26.09.2010 00:40
Ron, You are absolutely right. In an interview with Nikolay Golodnikov (a WW2 Soviet pilot who became a high ranking officer after the war) he states that early USSR Airacobras were pushed so that the Allisons did not even reach 1/2 life. They were good for optimum performance for about 50hrs, usually 10-15 sorties. They would use two power settings depending on the fuel they had available. If they used Soviet B-95 fuel that was pink in color, they would use up to 51" of boost. If they had US B-100 fuel (dark blue) they would push it up to 57". But Nikolay admits that there was some times that he would break the limiting wire on the throttle to access more power. He continued by saying the later Allisons would deliver 100hrs. Nikolay said by pushing past these limits the engine bearings would melt and the engine would seize up.
Ron, e-mail, 06.09.2010 07:53
I believe the Russians were getting only 60% of the engine life as advertised because of constantly running at full power.
Aaron, e-mail, 03.09.2010 22:30
ALLISON DIVISION, GENERAL MOTORS CORP., INDIANAPOSIS, INDIANA: December 12, 1942. A letter was sent to the Commanding General of the Army Air Forces, Material Center in Washington, D.C. The subject listed was: Service Use of High Power Outputs on Allison V-1710 Engines. This letter was informing the AAF that Allison was aware that military pilots were using 66" and even 70" of boost in combat. In the letter paragraph No.2 states: While we cannot help but feel pleased that our engines are standing up apparently to the particular squadron's satisfaction under these conditions, we also cannot help but feel that the selection of such high manifold pressures may be based on inadequate testing and that they are very apt to result in occasional failures which may occur some time after the operation at such high horsepowers but when operating normally or even crusing with resultant loss of pilot and aircraft. ENGLISH TRANSLATION: The V-1710-39 and -73 were being pushed to approximately 1780 hp. at 60 degrees F. and they were holding up just fine. The reason for the letter was that the supercharger blowing gear of the -39 and -73 was 8.8:1. The newer V-1710 were being produced with 9.6:1. This new gear would cause earlier detonation in the pistons. 1780hp. out of the engines in the P-40D,E&K and P-51&NA-73. That was in US squadrons. The Russian pilots had no hesitation about pushing their P-39s past the limit. TRANSLATION: 1780hp., match that to the published horsepower ratings of the P-51D, P-63 or Bf.109G. I would really like to see a performance testing of a P-39D being pushed to 66"/+18 lb. of boost. No wonder the Russians loved the plane.
Aaron, e-mail, 30.08.2010 18:56
From what I have read in many articles and interviews the P-40 was prefered by the USAAF because of its better range and maneuverability (roll rate/turning ability. The P-400 underpowered Airacobra did not help its image either. The P-39D was still underpowered but the pilots in New Guinea and the Russians removed all wing guns to improve overall performance. When the better powered P-39L, M, N and Qs came along the reputation damage was already done. In an interview with Russian ace Nikolay Golodnikov he states that the P-39 was a responsive and dynamic fighter. He further states that the Fokker (FW-190A) was not equal to the Airacobra (P-39Q?) in the verticle plane. He considered the FW-190 weakest characteristic (compaired to the VVS fighters) was its acceleation dynamic. He continued by saying that when they assigned fighters to escort bombers, the "attack group" would comprise of Airacobras or Lavochkins and the direct cover group was comprised of Yaks. He said it was better to have heavier aircraft in the attack group in order to chase down Germans in a dive.
Ron, e-mail, 24.08.2010 00:59
Makes you wonder about that P-39N restoring it's reputation in the West vs P-40 and F4F and dare I say Spitfire at that time. To my knowledge those stats haven't been too well published since. I'd be curious about the power-plant of course.
Aaron, e-mail, 08.08.2010 15:32
Ron, I sent you an e-mail on the location of the chart. Appears to be a military chart so I would guess the P-39N to be up to USAAF standards. Imagine how much quicker climbing the VVS Airacobra was. No wing guns and throttle to the wall...WOW!
Aaron, e-mail, 07.08.2010 19:13
Hi Ron, I tried to answer your questions earlier but info would not save. I'll try sending this first, then try again.
Ron, e-mail, 06.08.2010 22:45
Aaron, Where might I find this chart? Was it a stripped Russian version? They were happy with low altitude performance and a big stick, no frills needed.
Aaron, e-mail, 04.08.2010 18:56
Found fighter comparison chart showing P-39N reaching 397 mph around 10,000 ft. (338 at S.L.). Climb was 4175 fpm at S.L. and 4425 fpm around 8,000 ft. These figures taken from a graph chart comparing p-39N to others such as p-63, FW-190, ZERO, and others. No test weights or power settings given.
Ron, e-mail, 28.07.2010 06:53
Can you imagine a trio of ShVAK 20s in the nose in 1942 or so? Harmonized ballistics and punch of an La-7 (3xB-20 version, 1945). Unlikely but feasible. A bit of a reach, but how 'bout a 23-mm VYa cannon and twin UBS 12.7-mm in the nose? Less reliable but even more deadly. Still a dense enough pattern for dueling fighters but enough penetration to go through any armor in the air with even deadlier velocity than the ShVAK. Or forget the fighters and tackle bombers with Soviet guns matching the same caliber of the American nose guns but with harmonized ballistics: The twin UBS with the heavy long range NS-37-mm (like on the Yak-9T, but 3 instead of 2 guns). One kill per 1 second hit, no matter the plane!! That's at least four 37-mm shells out of 30+ in the burst vs 2 out of 12 with the original U.S trio of the identical caliber. The Soviet individual 37-mm and 12.7-mm projectiles were heavier to boot! The lighter U.S. 37-mm had only a third the power per second and was very short range (The unreliable Hispano 20-mm weighed in between the ShVAK 20-mm and the VYa 23-mm cannon).
Ron, e-mail, 28.07.2010 00:52
Just re-engine the P-39 with the new V-1710-93 would have given it a new lease on life by early 1943 without breaking stride. Poof, no more glass ceiling at 15,000'; 1500 hp boosted; 10,000' more altitude performance and 400+ mph! Go ahead and save the water-injected Allison for the P-63 later on for 1800 hp in good time. In one change the P-39 would fly like a real contender in the middle of WW2. It's power of maneuver would perhaps improve it's spin problems too.
Ron, e-mail, 27.07.2010 22:56
Edward W, I've read that when gun wear was sufficient, Russian UBS Cowl 12.7-mm guns and a hub ShVAK 20-mm cannon (B-20 for the later P-63) replaced them typically. Then I read that it happened sooner than later on occassion. A few liked the wing guns but mostly they were stripped to unweight the wings for dogfighting.
Ron, e-mail, 27.07.2010 01:43
The new V-1710-93 should have been retrofitted into all P-39s in late 1942 when it was installed in the new P-63. It would be over a year or 2 before the King Cobra would see combat in Russia. In the meantime, the little Cobra could've said saianara to their underpowered past. Stripped down by the Russians and re-gunned with their more efficient armament, it could have kicked more Luftwaffe butt than it did.
WagTheDog, e-mail, 25.07.2010 13:14
It's so refreshing to see bloggers having an "honest" discussion about the P-39, rather than simple hacking out old, tired myths and sound bites that have little merit. I've always been in the minority, it seems, that believes that the P-39 has been treated most unfairly by Western historians and WW2 veterans alike that never flew it, or flew it only in training, or at best, flew it only in the Southwest Pacific against the best that the Japanese had, in conditions (no ground search radar, terrible weather & dust conditions, inexperienced pilots & ground crews, etc. Most US pilots that actually flew it a lot seem to have really thought well of the AiraCobra, and those that didn't usually single out something like its short range, or lack of high-altitude performance (or inability to turn with a Japanese Zero!) as why they didn't like it. But I do have a question: According to some reports by Lend-Lease ferry pilots in the 1943-44 time frame I've read, upon taking delivery of their AiraCobras, the Soviets usually removed the wing guns (even the later .50 cal guns of the -Q model) immediately, to achieve less overall weight and a higher roll rate than US versions that retained them. However, I have a question (actually many questions, but I'll just keep it at one tonight)-- one of tollkeeper123' posts alludes to Soviet replacement of the AiraCobra's weapons with their (much better) Soviet analogues. --How often did this occur, and what Soviet weapon fits were used? I too have often wondered how much we could've improved our fighters' performance had we adopted some of the Soviets' very impressive aircraft guns!
Wulfiewulf, e-mail, 08.05.2010 12:04
what happened to all these Russkie P39 after the war, melted down for Migs I guess?
Would be facinating to see any pics of assembled war wearies!
Ron, e-mail, 29.04.2010 21:58
Truman, Sorry I don't have the data plates but since you worked at Bell, could you tell me about the synchronized rate of fire for the cowl .50 Cal. MGs? Did the reduction gear dictate a 300 r/m rate each no matter if the cowl gun was a Browning or anything else (faster UBS 12.7mm etc...)? How fast was the rate of fire for cowl mounted Browning .50 Cal. MGs if geared to the Allison engine mounted in the nose like the early P-40 or early P-51 for example? Not that I could expect such details, but thought I'd ask anyway. Seems like the P-63 had the same rate, though later faster Brownings were available for it. But the wing mounted ones were faster than in the earlier P-39Q. Am I wrong? Could you set the record straight?
Truman, e-mail, 31.03.2010 23:01
I worked at Bell Aircraft. I like the P-39 Airacobra. I am presently involved with 4 P-39 projects. One is the plane that was pulled out of the Russian lake after 60 years. One is "Cobra I", which crashed into Lake Ontario in 1946. The other two are currently being restored in Australia. I am assisting them by supplying the approximate 180 different stencil information and locations via 1/12 scale drawings. I have finally rounded up all the info. for all the markings on the inside of the cockpit doors- even to the size and style of lettering. I have all the info. for the data plates on the inside of the cockpit rollover structure. WHAT I DON'T HAVE IS THE INFO. ON THE SMALL (2 1/2" x 1 1/4") DATA PLATE THAT IS FOUND ON 17-18 SUB-ASSEMBLIES OF THE PLANE. If anyone has one of these data plates that they could make a GOOD copy of, or they have a GOOD photo of one, I would appreciate it very, very much if you could send me a copy of it. The data plate has spaces for: Serial No.,Dwg. No., A.F.T.O. No.,Inspection, and Modif. No. I am especially interested in knowing what the "stamped/punched" info. is in the space after Serial No. My intention is to replicate all the markings on the doors plus the rollover data plates and the small subassembly data plates.
Thanks for all of your help, Truman
Ron, e-mail, 18.03.2010 04:13
Can you imagine a seriously stripped cobra? No added armor (the motor in back of the pilot is plenty). No guns in the wings. Just 1 radio. Take a Mikulin AM-38 in place of the Allison. A ShVAK 20mm and 2 UBS 12.7mm in place of the Olds and Brownings in the nose. Voila! (French, I know. What's the Russian word?) Finally, the interceptor Bell meant it to be! Now you can climb, roll, and turn even better. No more altitude sickness. And the 3 guns are putting out more rounds per second (40+) than the 5 American guns did (37), and they'd have harmonized high-powered ballistics. All the better for dogfighting. Need a 37mm for enemy bombers? Use the Soviet NS-37 for more than twice the firepower of the U.S. Olds 37. Overheat too much? Keep them on the northern front of the Soviet Union. Not enough range? Use drop tanks until engaged with the Luftwaffe. For all we know, many of these things were done, but not by us. What we did was take the P-63 fighter-bomber which was a ton heavier (loaded) than the P-39 fighter, and add more armor (till it could hardly take-off) for target practice. We couldn't see the value of a mid-engine aerobatic fighter to counter the nimble Japanese. The Russians did. They even downed a Nakajima interceptor with a P-63 no less.
Ron, e-mail, 16.02.2010 02:25
WHEN i mentioned intake, I mean in the combustion chamber. It was too undeveloped vs it's peers. The Connie inverted inline became a dead-end unfortunately. The best allied inline should have replaced it on the production line back when it first disappointed Bell. The Merlin or powerful Mikulin AM-38. The Klimov M-105 was not more powerful than the Allison and had the negative 'g' problem of the early Merlins. Failing all that, make an American injected and boosted 'DB-601' style inline for that period. That's what the Italians did well (Alfa Romeo Monsonie) but the Japanese, not so well (perhaps weight reduction made the Ha-40 worse in this case). If Allison and Continental had combined, who knows? All this could have been developed on the Airabonita without delaying the P-39 production.
Ron, e-mail, 07.02.2010 08:49
I know it is fantasy to play what if.. But since the basic spin problem was due to a light nose after too much ammo was spent, what if the pilot and weapons swapped places (cockpit forward as in the trainer design but without the back seat) putting the ammo on the c/g. Longer gun barrels wouldn't hurt, improve ballistics if anything (of course the hub gun would go, but 4 synchronized UBS/ShVAK-like guns could be in the sides of the fuselage) If that's not pretty enough, then displace the lost weight as you go, using ballast or something (sliding armor plates). The problems with tail rudder and elevator contact during a spin could be simply avoided by moving the tailplane forward ala Zero or P-51, perhaps enhancing turning time too. P-39s didn't sputter bunting into a negative 'g' dive like the early Merlin powered RAF fighters of the same period (or Yaks too for that matter). So why not install the improved Allison like those in the P-38 (at least a contender vs P-39/P-40). Why did Bell take so long before fielding a water injected 2 stage supercharged Allison powered P-63C, 1945? Like the early P-51 with a refined Merlin replacing it's Allison engine, Bell (and Curtis too) should have followed suit. Allison should have followed in the steps of Packard which started producing Merlins for the Mustang. At least a few production lines anyway. North American didn't wait around like Bell once the negative 'g' trouble was cured on the Rolls-Royce Merlin. Either way, U.S. fighters being produced from about 1943 on should have only had competitive powerplants, export or not. No excuses. As it was, the P-39 with a 1 stage supercharged Allison would inevitably use too much war emergency to last very long due to overheating. A 3rd point would be this. When the Russian delegation visited the Bell factory to give input for the P-63 they should have installed and demonstrated the Soviet guns of the same caliber like the NS-37 and the UBS 12.7 mm and for the P-400 fans the ShVAK or the later B-20. I know I mentioned this before. But P-39s were faulted for mixed ballistic performance. Switching to these guns at the Bell factory (or something like them) would have addressed this. It's no secret that these powerful weapons found their way into Russian Cobras but certainly U.S. pilots should have benefitted too. Bell should have ceased installing the .30 Cal wing guns long before the P-39Q! At least an American version of the high velocity NS-37 cannon and the others would have almost tripled the total firepower! Thus 3 guns would suffice. Their muzzle velocity was all on the same page too. The complaints by U.S. airmen about the slow synchronized rate of fire for the browning .50 Cal (12.7 mm) P-40B cowl guns averaging around 425 r/m made the P-39 look bad at 300 r/m while the Soviet synchronized 12.7 mm UBS fired over 800 r/m each! And the bullet was even heavier not lighter 48 vs 43 gm. Gone would be the jamming headaches of the Olds T4 37 mm or the Hispano 20 mm cannons. The RAF Hispano was more refined than the American Hispano but both paled in comparison to the ShVAK 20 mm or lightweight B-20 in Russian fighters. All had great ballistics but the Hispano was less reliable. On the other hand it fired a heavier shell 130 vs 98 gm. The Hispano was slower and I don't know if it was ever synchronized like the Russian 20 mm. Even then they were as fast as the Hispano unsynchronized: 600-710 r/m - most; ShVAK/B-20: around 750-850 (708 r/m synchronized). I'll leave the Vya-23 alone for now. The P-39 that the U.S. pilots regarded as a dog could have been so much more.
hal, e-mail, 04.02.2010 20:14
Hmmm, where to start. Main reason Soviets were more successful with P-39 was reduced weight by deleting worthless .30 cal wing guns that weighed (with ammo)400 pounds ("good for damaging German paint" said Soviets). At 7100# Airacobra was equal to 109 and 190 at all altitudes up to 26,000'.
Turbo was deleted because it wasn't ready or reliable. If not deleted P-39 would not have been ready for WWII. Turbo P-38 didn't see combat until 12/42, P-39 without turbo was ready in Jan/41. U.S. would have been in trouble without P-39 in 1942.
Armament (without .30 cal wing guns) considered excellent and devastating by Soviets. No mechanical problems occurred with 37mm cannon unlike U.S. Soviets used P-39 as air superiority fighter (interceptor/escort) not ground attack resulting in 4 0f top 5 Soviet aces flying Cobra.
P-39 was finest fighter in Soviet inventory and was discarded by U.S. much too early. Allison engine with mechanical second stage (in P-63) would have equalled P-51 Merlin performance at high altitude. U.S. gave up on P-39 based on promise of P-47 (somewhat unfulfilled) and gave them to the Soviets who deleted the worthless wing guns and won the war with them.
Ron, e-mail, 31.01.2010 08:21
Another problem concerned the P-39's Allison V-1710 engine. The engine's advertized operational life of 250 hours fell short in Russian front combat conditions, where it lasted only around 65% of that. The degraded performance was attributed to excessive boost that overheated the engine oil and fused bearings. Use of poor quality oil and gasoline also contributed to this. When there was a shortage of American spares over 100 P-39s were refitted with hardy Soviet M-105P engines. Can you imagine one of those with Russian weapons installed when the U.S. originals were worn out as well?
Ron, e-mail, 31.01.2010 07:49
Soviet P-39 kill ratio against the Luftwaffe was 4 to one in favor of the Cobra to the end of WW 2. Many of it's losses were due to fatal spins when very low on ammo in the nose. Even many top Russian pilots fell victim to this accident. Very quick reaction was necessary to recover.
Ron, e-mail, 24.01.2010 07:29
Just been reading online how Allison engines in the P-39 suffered from poor intake design aside from the turbocharger cut to save the expense, making it less capable at any altitude than it could have been. This, and the fear of having any high-tech well-developed fighters exported (P-400) or otherwise captured. I couldn't believe it. The Russians didn't care. Their aces made it the #1 U.S. fighter for top Allied aces in history anyway. Pokryshkin refused to trade in his 'little Cobra' for a new La-7 !! Imagine if Allison had switched to building Merlin engines (evidently Packard couldn't spare any of their Merlins due to the P-51 demand). Then the Cobra would have fulfilled it's designed intention as an interceptor with a big stick (3+kg/s) at all altitudes. Speaking of firepower, it has been critisized for having disharmonious mix of guns. This too was remedied by the Russians. This may help account for it's success in their hands. Too bad the USA couldn't do it first.
DW75, 22.12.2009 13:45
eliko116, all Pokryshkin´s kills not being counted had nothing at all to do with it being a LL plane, it had everything to do with the Soviet airforce at the time only counting kills that were 100% proven, which usually mean only kills over friendly territory.
Obama, e-mail, 06.11.2009 22:16
cocksucking nonces
eliko116, e-mail, 14.10.2009 22:27
VVS also used it as an escort plane for il-2s .Pokryshkin ( soviet ace , 59 victories , p39n # 100 ) prefered this plane even when the VVS comand tried to force him change to La-7 . He wrote at his memuars that he loved the armament of P-39 . His P-39 was firing all guns at once whith one trigger . I heard from my grandfather that he was best scoring VVS pilot , but he was flying american plane thats why some of his victories wans't get into account . Best soviet ace had to fly soviet plane . Sorry 4 my eglish . Thanks .
Ronald, e-mail, 19.09.2009 04:12
There was a plan to try a Merlin in the P-63 but it didn't materialize. I guess the idea of focusing this bird on ground support meant the Allison was good enough and let all available Packard Merlins go to P-51s. Still, to see if it could have at least proven itself, just for the record. Check out the P-63 page.
paul scott, e-mail, 17.09.2009 22:41
What a world-beater this could have been, had the supercharger been installed - it's not the thing I would've thought the USA would've overlooked. (I'd compare this oversight to Britain's stupidity with the non-forward armament of the Boulton Paul Defiant). A nose-mounted 37mm Cannon, and a nosewheel would've made it a formidable opponent. I liken this to Britain not having had a 'floatplane' fighter on its ships (U-boat War). A real shame.
Ronald, e-mail, 30.08.2009 02:54
525 mph red-line dive speed. This is to alter my earlier post. 380 turn time was 19 Seconds (D&Q). The D climbed to 5km in 6.5 minutes and the Q reached 6km in 8.5 minutes. This comared favorably with the Fw 190A-4.
ozona, e-mail, 09.08.2009 09:14
Along with losing th P-38 prototype for a photo-op & continuing to produce the B-17 instead of replacing it with the Mosquito one of the biggest mistakes made by the Army Aircorps was messing up the P-39.
In April 39 it did 400mph in trials & could reach 20k ft. in 5 min a minute faster than the P-38. Then the idiots @ NACA fixed it they took away the B5 GE turbocharger & moved the air intakes among other things. They took a 400MPH early 1939 plane & turned it into a 355MPH plane worthless above 15k ft. To add insult to injury they took the marvelous R.R. Merlin & put it in the P-40. Who knows how fast the P-39 would have been with the Merlin, no 37mm gun, laminar flow wings like the P-51 & Hamilton Standard paddle type 4 blade props (P-47).
Leo Rudnicki, e-mail, 15.05.2009 02:18
British Airacobras (P-400) mounted 2 .50 in upper cowl, syncronized, w/ 200 rpg and 2 .30 in wing w/1000 rpg. plus the 20mm Hispano.
Sgt.KAR98, 11.05.2009 02:14
Why U.S rejected this beauty?
D Nitz, e-mail, 10.05.2009 07:18
I have a nose gear fork that may be for an early Airacobra. I can send photos to anyone who can ID this gear. The overall length of the piece is about 40". Inside of the fork is about 15". Thanks for any help.
Ian, e-mail, 22.04.2009 13:28
Can anyone verify the armament of the P39's in RAF use. The 20mm Hispano with 60 rounds is a constant but the machine guns vary. 2x0.5 & 4x0.3 OR 6x 0.303 OR 2x0.5 & 4x0.3. It's a small point I know but I'm a real anorak about these things!!
leo rudnicki, e-mail, 08.04.2009 18:13
I finally read a spec sheet which gave the range of the Cobra as 300 miles. This would correlate better with the fact that the P39 did not complete it's performance evaluation against the Aleutian Zero A6m2 because it ran out of gas. The 746 mile figure is higher than the usual 675 that is common. Since the prime reason for the layout was to carry a big gun, I wonder why the RAF never thought to fit one of the Vickers 40mm guns used on the Hurricane IID in the nose.And a merlin. I like to fix things 70 years too late. And the nickname of the P39 is Kobry, tovarich.
Ronald, e-mail, 28.09.2008 09:01
Climb rate ranged from 2,600 to 4,000 ft/min. Terminal dive was 475 mph. Pullout was shallow. Controls were still light at high speed. It out-turned Bf 109 and Fw 190s. Roll-rate was good: 75 degrees/sec. @ 235 mph. If ammo in the nose got too low it could be spun out of control.
Ronald Boren, e-mail, 22.08.2008 09:31
Since the top allied aces were mostly Russian P-39 pilots, and it had the slowest US guns in the nose (37mm = 2 rps; 12.7mm = 5 rps each) and the Soviet NS was the fastest 37mm (4 rps) and the UBS was the fastest synchronized 12.7mm (13 rps) cowl gun, I wonder if they swapped guns over time. We Know that they most often stripped off the wing guns for better handling in a dogfight. Some preferred the Bell P-400 for it's faster 20mm Hispano (10 rps) in place of the M4 37mm (both US cannon were prone to jam unless you fired only a couple of rounds at a time). To bag a Fw 190 or Bf 109 in 1943-44 you needed a pattern of fire denser than 12 rps total! The Yak-9T averaged 18 rps with just 2 guns: an NS-37 and a UBS 12.7mm in the nose, and it was a hit in air-to-air kills! A ShVAK 20mm in the hub and twin UBS 12.7mm in the cowl would have given a P-39 40 rps - decent for only 3 guns. Then there is the Soviet VYa-23! 9 rps but double the punch of the 20mm. Now the prowess of the Russian P-39 begins to seem more plausible as an ace-maker.
J Cobb, e-mail, 16.02.2007 01:26
I would like to get tech data/specs for all modifications of the P-39. I am also looking for any info on the original "Whistlin Britches" flown by the 69th fighter squadron.
Faldman, e-mail, 15.02.2007 09:44
can i have some drawings from aircobra if i can because i am going to r/c plane racings.The aircobra is faster and smaler than mustang ,spitful,MEE e.c.t. plz!
