XP-39 and the Claims

[P-39 Expert]

I am also in a confused state about the P-39. I just got through reading the book "The First Team and the Guadalcanal Campaign" and I had read General Kenney's report relative to the fighting on New Guinea. Both time periods were similar and there was overlapping missions. Relative to the P-39, General Kenney wanted more of them, he preferred the P-38, but they were unavailable, but he did want more P-39s and didn't ask for P-40s. He did mention the inability to reach the high flying Japanese, true with the P-40s also. As far as the First Team book, there were several P-39s and P-400s with the Cactus Air Force. There was mention of their lack of performance at altitude but nothing more other than they participated often on ground attack and some escort missions. No derogatory comments about their performance.

What is confusing is that they were not dogs. Comparing the performance of the P-39D with the other players in that theater, the P-40E, F4F-4, and the Zero, the P-39 was faster than all, maybe equal to the P-40 at SL, up to 25,000 ft. ( some 15 to 30 mph faster than the Zero), and it could out climb all, except the exceptional Zero, from SL to 25,000 ft. except being equal to the F4F-4 at 25k. It also would beat all except the Zero to 20k in time to climb.
Data from America's Hundred Thousand and test results.

So, why did the P-39 get such a bad reputation? I can think of only one real reason. Pilots, which may have come straight out of pilot training, were not trained in utilizing the speed ability of the aircraft, ala, P-40 pilots. From AHT, the word was stay under 15000 and above 300 mph and the Zero couldn't get you, ie, you could break off any time. even at 20k, the P-39 had a 30 mph speed advantage over the Zero. At 25k, it only had an 18 mph advantage over the Zero.

We had three fighters in frontline service in all of 1942 until the P-38 entered combat in December. The Navy had the F4F Wildcat and the AAF had the P-39 and P-40. Their main adversaries in the Pacific were the A6M2 Zero and the Ki-43 Oscar who had very similar performance to each other.

AHT is a great book, but a lot of information has surfaced in wwiiaircraftperformance.org since AHT was published in 1999. Official performance charts show that the P-39D/F/K/L of 1942 with the early 8.8 geared Allisons were indeed faster at all altitudes than the F4F, P-40E/K/L and the Zero/Oscar. Their critical altitudes were all around 15000'. The F4F did about 320mph, the Zero about 330mph, the P-40 about 340mph and the P-39 about 370mph with those speeds falling off above critical altitude at about the same rates. On paper the P-39 had a 40mph speed advantage over the Zero above critical altitude.

The P-39 also outclimbed the other American planes. Versus the F4F the P-39 had a 500fpm advantage at 12000' which narrowed to about the same as the F4F at 25000'. P-40 climb was about the same as the F4F at 12000' then a steady 300fpm less than the F4F on up to their operational ceilings (1000fpm) around 23000'. The Zero outclimbed the three American planes substantially climbing at about 1850fpm at 20000' while the F4F/P-39 were making about 1200fpm and the P-40 about 900fpm at that altitude. After the 3000rpm climb limit was raised from 5 minutes to 15 minutes in mid '42 the P-39 and Zero climb rates were about the same at 20000'. Merlin P-40F/L had approximately the same performance as the P-39.

So the P-39 was 40mph faster than the Zero and could climb with it. Why wasn't it's record against the Japanese better? Two reasons:

1. Pilot training/quality. The IJN Zero pilots were the best in the world at the time. Plucked from elementary school and continuously trained to be fighter pilots flying the most maneuverable fighter of the time. Experience from their war with China and their late '41/early '42 conquests. Rigorous training and combat experience. That the Navy with their overmatched F4F did as well as they did against the Zero is the result of THEIR excellent training. Navy pilots graduated with over 600 flying hours as compared to their AAF counterparts with only 200 hours. They had the training and discipline to engage the Zero only when they had the altitude advantage.
2. Drop tanks: A 110 gallon drop tank on an already overweight 7650# P-39 meant that at normal power 2600rpm the combat ceiling (1000fpm) was about 18000'. IJN G4M bombers came in at between 18000' and 22000' with Zero escort a couple thousand feet above them. The P-39s with drop tank couldn't reach the bombers or their escort. Without a drop tank the P-39 could climb to 22500' easily at normal power (2600rpm) and well above that at combat power (3000rpm). But interception missions were normally flown with the drop tank since their normal mission was escort of C-47s or bombers. If on an alert for an interception mission the drop tanks were in place, but if for whatever reason the alert was cancelled they could go ahead and fly their normal escort mission. After altitude was reached the tanks would only be dropped at the start of their attack run. Virtually every P-39 mission was with drop tanks. Hardly any F4F missions carried drop tanks. The 1942 P-39 was good at escorting bombers and transports at medium altitude with a drop tank and was a good interceptor at higher altitudes without a drop tank. But they always carried the tank.

 

[varsity07840]

Hi Wuzak,

Yes, I'm looking for proof, like anyone interested in what happened. You, me, or anyone else claiming something didn't happen is no proof one way or the other. If there was a test, it is likely recorded somewhere. So, I'm hoping the test document surfaces sometime. Otherwise, there is no point discussing the XP-39 peformance with just opinions. Everyone has one.

Works both ways, Wayne. There is no actual evidence that it DIDN'T go 390 mph either.

It was not a non-representative hot-rod. It was a prototype that I'm sure they flew when they thought it was airworthy. There are a great many WWII fighters that made first flights without armament. As for your question, you'd have to ask Langley. I wasn't there when the calculations were made. But a reprint of the book/paper in the link is available if you are interested.

Your last statement I believe I covered in the original post.

The data show a P-39N that was a whisker away from 400 mph in 1942. So, while the airframe wasn't one of the faster in the war, it was also faster than some of the mainstays such as the Bf 109E. It didn't have the altitude capability of the Bf 109E but, at least in the Med and Pacific, it didn't need that either. Apparently, more altitude capability wasn't needed in Soviet service. They just stayed down low and hit the German troops, forcing the Luftwaffe to either come down and fight or stay high and be a non-factor. I'm not touting the P-39; I never was a fan of the type. I'm just observing that the test data don't seem to show me as much of a dog as is commonly believed, unless I'm missing something.

By 1942, the Germans were flying Bf 109Fs and Gs, so a comparison to the Bf 109E is meaningless. The Soviet Air Force was strictly a tactical air arm. The P-39 suited THEIR requirements. The P-39 was intended to be an interceptor and in that role it failed miserably. If the P-39N was fine for service in the Pacific, why was it replaced with P-38s and P-47s? The 35th Fighter Squadron's P-39s were replaced in mid 1943 by P-40Ns, not P-39Ns. The pilots were glad to get them.

 

[GregP]

Hi Varsity,

It was replaced in Pacific service largely by the P-38 because: 1) the P-38 was withdrawn from the ETO and they were available, 2) The P-38 offered the over-water advantage of a second engine to get you home, and 3) There was no real point in having the extra logistics chain all over, so P-39s that remained were grouped together logically as everyone might expect.

The P-47 began to replace the P-39 when it came into general service. If was newer, much longer range than the P-39, hit harder, and was a much better overall airplane. For the first time, they could get to and fight at higher altitudes.

A comparison to the Bf 109E is not anywhere near meaningless. The Bf 109E and the P-39 were frequent antagonists in the Med and African desert areas. The Bf 109E was flown by the Germans well into the war on all fronts. You don't retire an early to mid-life fighter simply because a newer one becomes available. You retire them as they break down, need overhaul, or get lost in action. The Germans never had enough fighters and they would not waste a Bf 109E without a good reason.

In mid-1943, the 35th did get P-40Ns. Their P-39's were worn out or near it. Any new plane would have been good, and the P-40 was a bit better in some ways than the P-39. They had about the same speed and the P-40 likely handled better and probably handled rough fields better. But it certainly didn't outclimb the P-39 below 16,000 feet and moving from a tricycle gear to a conventional gear aircraft surely caused a few landing accidents. I bet the 35th hadn't landed a taildragger in a couple of years! The Allison in the P-40 was also much easier to work on than in the P-39. They surely didn't miss the driveshaft coming through their legs. They might have missed the cannon when strafing ships, but it jammed fairly readily ... so maybe not.

 

[XBe02Drvr]

The P-39 was intended to be an interceptor and in that role it failed miserably.

As mentioned by P39Expert above, the P39D's combat performance as an interceptor was primarily established on New Guinea and Guadalcanal, where it was handicapped most of the time by being configured for its other mission, bomber escort, lugging a 110 gallon drop tank around. Additionally, it oten suffered from lack of reliable early air raid warning, dictating an engagement from a climb underneath the raiders. No time and altitude to get accelerated to combat speed and no initial altitude advantage. Sitting Duck City.
Cheers,
Wes

 

[tomo pauk]

Hi Varsity,

It was replaced in Pacific service largely by the P-38 because: 1) the P-38 was withdrawn from the ETO and they were available, 2) The P-38 offered the over-water advantage of a second engine to get you home, and 3) There was no real point in having the extra logistics chain all over, so P-39s that remained were grouped together logically as everyone might expect.

The P-47 began to replace the P-39 when it came into general service. If was newer, much longer range than the P-39, hit harder, and was a much better overall airplane. For the first time, they could get to and fight at higher altitudes.

P-38 was not withdrawn from ETO. Availability was a factor of Lockheed managing to make more P-38s by every new day.
P-39 was loathed by Gen Kenney since it was of too short a range (Kenney didn't rate the P-40 very high either), so it got to go away once better A/C were available. Introduction of P-38s meant an extra logistic chain, with or without the P-39.

A comparison to the Bf 109E is not anywhere near meaningless. The Bf 109E and the P-39 were frequent antagonists in the Med and African desert areas. The Bf 109E was flown by the Germans well into the war on all fronts. You don't retire an early to mid-life fighter simply because a newer one becomes available. You retire them as they break down, need overhaul, or get lost in action. The Germans never had enough fighters and they would not waste a Bf 109E without a good reason.

Why not leveling the playing field - comapring the new P-39 vs. a new German or Italian fighter?

 

[GregP]

Yes, Tomo, most of the P-38s were withdrawn from the ETO except for a small number. Most went to the Med and PTO, as you well know. Only a comparatively few stay in Europe. And you are missing my point about the P-38 and logistics. There was no use keeping the P-39s at the same base as the P-38s because they'd have to support two logistics chains. So, rather naturally, the P-39s that remained were grouped together to minimize the logistics, for the most part. Yes, there were exceptions to almost any policy or rule, as you well know.

I'm not talking about leveling the playing field at all, Tomo. I'm talking about the aircraft that were actually there. The P-39s and P-40s in the Med and Africa were not factory-new examples. They got what they could get because the primary fronts were elsewhere. Sure, the P-39s and P-40s fought Bf 109Fs and Gs, but they fought a heck of a lot of Bf 109E's, too. As I said, the Luftwaffe didn't retire a Bf 109E for no good reason. Neither did the Allies retire our fighters before their time. As for new Italian fighters, there were very few, but they did, in fact exist, so they might have showed up. They built 1,150 MC.202s and a whole 262 MC.205s. I'd say they ran across German fighters much more often, but I'm sure there were Italians fighters there, at least up until 8 Sep 1943 when Italy signed the Armistice and ceased combat. We were still flying older P-39s in the Med when there were no more Italian fighters flying anywhere on combat missions.

 

[varsity07840]

Yes, Tomo, most of the P-38s were withdrawn from the ETO except for a small number. Most went to the Med and PTO, as you well know. Only a comparatively few stay in Europe. And you are missing my point about the P-38 and logistics. There was no use keeping the P-39s at the same base as the P-38s because they'd have to support two logistics chains. So, rather naturally, the P-39s that remained were grouped together to minimize the logistics, for the most part. Yes, there were exceptions to almost any policy or rule, as you well know.

I'm not talking about leveling the playing field at all, Tomo. I'm talking about the aircraft that were actually there. The P-39s and P-40s in the Med and Africa were not factory-new examples. They got what they could get because the primary fronts were elsewhere. Sure, the P-39s and P-40s fought Bf 109Fs and Gs, but they fought a heck of a lot of Bf 109E's, too. As I said, the Luftwaffe didn't retire a Bf 109E for no good reason. Neither did the Allies retire our fighters before their time. As for new Italian fighters, there were very few, but they did, in fact exist, so they might have showed up. They built 1,150 MC.202s and a whole 262 MC.205s. I'd say they ran across German fighters much more often, but I'm sure there were Italians fighters there, at least up until 8 Sep 1943 when Italy signed the Armistice and ceased combat. We were still flying older P-39s in the Med when there were no more Italian fighters flying anywhere on combat missions.

You sir, don't know what you are talking about. Your faulty contentions are too many to refute, but are faulty none the less.

 

[jetcal1]

You sir, don't know what you are talking about. Your faulty contentions are too many to refute, but are faulty none the less.

Please pick a few and refute away!

 

[XBe02Drvr]

Please pick a few and refute away!

With legitimate references!

 

[Shortround6]

the P-38 was withdrawn from the ETO and they were available,

In late 1942 the P-38s in England were sent to North Africa, none of the P-38s in England were sent to the Pacific. Attrition In North Africa was high. Lockheed could barely keep up with supplying North Africa. A trickle went to the Pacific. All of the ones going to the Pacific came from the United States. Pacific Squadrons did not get hand-me-downs from England or North Africa/Italy. Lockheed production was kind of up and down from month to month in 1942 and most of 1943 but the last 3 months of 1943 saw production roughly double. 1054 planes built in the last 3 months compared to 1443 for the previous 9 months. Production in 1944 was almost exactly the total number built in 1941, 42 and 43 put together. The P-38s sent to England in the fall of 1943 stayed in England, they were just transferred from the 8th AIr Force to the 9th Air Force as more P-51s arrived. When these P-38s left England in 1944/45 they went to France, not to Italy or the CBI or the Pacific.

One has to be careful when talking about the P-38 being withdrawn from the ETO, They were withdrawn from the 8th AIr Force twice, once to go to North Africa for operation Torch and the 2nd time they didn't really change location, they just changed command structure.

As far as the 109E goes. It is quite possible the P-39 did fight some 109Es in North Africa, but I doubt there were very many. The P-39 shows up in NA during Torch just after Torch I don't think any were shipped around Africa or flown across Africa? Two P-39 fighter groups, the 81st and the 350th fly from England to North Africa in Jan 1943, at which point the newest 109-Es anywhere would be 1 1/2 to two years old. You can't really combine 109Es and Fs in a squadron or group (perhaps the group?) because the performance is so different. Some 109Es may have been being used as fighter bombers in Jan of 1943? By April of 1943 the Free French are being given P-39s. By May of 1943 the 350th group is assigned patrol duty in Algiers west of Spanish Morocco.

 

[XBe02Drvr]

You sir, don't know what you are talking about. Your faulty contentions are too many to refute, but are faulty none the less.

And you, sir, are being unnecessarily insulting to an informed and long respected member of our community.
There are plenty of less dismissive ways to present a disagreement over factual information. Like citing source data. And explaining how it led to whatever your conclusions are.
Cheers,
Wes

 

[FLYBOYJ]

I suggest some folks chill out!

 

[XBe02Drvr]

I suggest some folks chill out!

Roger. Read you 5 square. Wilco.

 

[GregP]

Hi Varsity,

I suppose we read different books ... but the war is over and we know the outcome. I don't really want to pursue nitpicking.

I just love the aircraft. They are fun to work on and see fly. Cheers.

 

[varsity07840]

Please pick a few and refute away!

Why did Spitfires replace P-39s when the 31st FG got to England?
Name one front line German JG that was flying 109Es in 1943
P-39s, P-40s and P-38s were at the same bases in the Pacific all the time. Ever heard of Port Moresby or Henderson Field?

 

[jetcal1]

Why did Spitfires replace P-39s when the 31st FG got to England?
Name one front line German JG that was flying 109Es in 1943
P-39s, P-40s and P-38s were at the same bases in the Pacific all the time. Ever heard of Port Moresby or Henderson Field?

Please feel free to continue. I'm particularly enjoying the tone of your response. (Hint, hint.)

 

[XBe02Drvr]

Why did Spitfires replace P-39s when the 31st FG got to England?
Name one front line German JG that was flying 109Es in 1943
P-39s, P-40s and P-38s were at the same bases in the Pacific all the time. Ever heard of Port Moresby or Henderson Field?

I'm with jetcal; please continue. But bear in mind, this forum is not a troll hole. There's a lot of accumulated knowledge and experience here to be shared with you, if you're willing to treat people in a civil manner, and they will do the same for you. If you're looking to polish your ego with your scholarly prowess, this is not the place to do it.
Now let's hear your description of the events of Port Moresby and Henderson Field, with squadrons, aircraft types, dates of tours of duty for each, and combat performance and kill/loss success rates. Don't forget relative effectiveness of aircraft types on both sides, and of course, cite your sources.
This has all been hashed out thoroughly over the years, and we'd be interested to see what new info you bring to the table.
"Over!"
Cheers,
Wes

 

[varsity07840]

I'm with jetcal; please continue. But bear in mind, this forum is not a troll hole. There's a lot of accumulated knowledge and experience here to be shared with you, if you're willing to treat people in a civil manner, and they will do the same for you. If you're looking to polish your ego with your scholarly prowess, this is not the place to do it.
Now let's hear your description of the events of Port Moresby and Henderson Field, with squadrons, aircraft types, dates of tours of duty for each, and combat performance and kill/loss success rates. Don't forget relative effectiveness of aircraft types on both sides, and of course, cite your sources.
This has all been hashed out thoroughly over the years, and we'd be interested to see what new info you bring to the table.
"Over!"
Cheers,
Wes

My comment about different aircraft at Port Moresby and Henderson field was in response to his comments that P-39s and P-38s would not be kept at the same airfields because it would mean supporting two logistics chains. I don't need to polish my ego, but since you asked, Ill give you an example several logistics chains. In the 5th AF at Port Moresby, by early 1943, the 7th and 8th fighter squadrons had P-40Es and P-40Ks. The 9th FS had P-38Fs. The 39th Fs had P-38Fs. The 40th and 41st FSs had a mix of P-400s, P-39Ds and P-39Fs. The 35th and 36th FS had a mix of P-400s and P-39D-1s. The 80th FS had P-38Fs. I've no intention of relating the history of the air war in the pacific for you. Perhaps you need to pursue some sources assuming that there was no sarcasm in your comment. There is no new info to bring to the table. Only the difference between fact and conjecture.
Cheers.

 

[GregP]

To be fair to Varisty, the Bf 109E was generally being phased out by late 1941, true. But "being phased out" doesn't mean you scrap all of them overnight and replace them all at the same time wholesale. The German aircraft industry wasn't that good at production. All told, they made some 3,478 Bf 109E's including E1, E-3, E-4, E-5, and E-7 models. The entire German Messerschmitt Bf 109 production for 1942 was 2,658 aircraft so, even if they replaced a Bf 109E every single time they could do it, as soon as the new Bf 109F / G was built, they probably couldn't convert everyone by the end of 1942, despite the losses in the Spanish Civil War and early WWII. I bet every forward unit had at least some if not a majority of newer models by the end of 1942, but let's face it, the Mediterranean Theater wasn't exactly the number one priority for either the Allies or the Axis. The "new" F's went to the units defending the Reich first, and the Russian Front, which opened just before the F's came out for deployment to front-line units.

So, I'd bet some E models soldiered on unless worn out until sometime in 1943. No, I don't have the Luftwaffe unit aircraft on hand by type and date and doubt anyone else does off the top of their head either. When the P-51D came out, there were many units that flew the B/C and D/K together for quite a long time. Ditto with bubble-top Thunderbolts. Yes, they were replaced with newer planes, but not all at once at the same time. The only time a unit got wholesale replacement was when the unit converted to a new type. If the went from, say P-38s to P-51s, they'd get an entire batch of P-51s all at once or nearly at once because they were converting from one type to another. Otherwise, they'd get replacements as they became available from production and their allocation priority got to the top of the stack.

The Germans sometimes converted from the Bf 109 to the Fw 190, and then, the unit might get an entire batch of Fw 190s, which freed up the replaced Bf 109s for re-deployment to units still flying the Bf 109. Erich Hartmann's favorite aircraft model was the Bf 109F and he stayed with the Bf 109 even when he was specifically asked to convert to the Fw 190. His reasoning was that someone familiar with an aircraft was better able to survive than someone who was a veteran, but just getting used to a new aircraft model. His superiors agreed. He flew his Bf 109F well past the time when it should have been traded for a Bf 109G, according to several articles I read in the past, and according to Erich himself when he visited the American Aces Association in Mesa, Arizona in the 1980s. He finally did trade for a later model 109 when his F became battle-weary. If I remember correctly, he traded his F for a G in fall 1944. The F's SHOULD have been gone earlier, but he liked the lighter weight of the F over the much heavier G.

As for the P-38s getting transferred, Jimmy Doolittle asked for an RAF evaluation of U.S. Fighters. It is well documented that Eric Brown was instrumental in these evaluations and stated that the Fw 190 could hit Mach 0.75 in a dive but the P-38 was constrained to Mach 0.68. making it "useless" in Europe. After the evaluation tests at Farnborough, the P-38 was kept in fighting service in Europe for only a little while longer. By September 1944, all but one of the P-38 groups had converted to P-51s. The last P-38 group flew F-5 PR Lightnings. This wasn't in 1943, but they DID get transferred out of the ETO except for photo-recce versions by Sep 1944. There were at least two P-38 groups transferred to North Africa in 1942 - early 1943, including the 1st, 14th, and 82nd. The 1st and 14th were sent in Nov 42 and the 82nd was sent to replace the depleted P-38s of 1st and 14th somewhat later, if you check.

Last, about the logistics, what I should have said was that one Group would NOT fly mixed aircraft for long due to the two logistics chains. They might be at the same field, but one Fighter Group flew one aircraft type out of pure logic and the otherwise stupid logistics chains. There would also be the need to have pilots, mechanics, and mission planners trained on both types, which was just stupid to consider unless there were some other glaring reason for doing so.

 

[jetcal1]

BF109E-4/B W. Nr. 5580 (Built in 1940) was in service at least until February 24th 1942 in Norway as that is the date that Uffz Hunold made a navigational error and ended up in a forced landing on Lake Balivik which was frozen at the time.
Also consider a BF109-F4 forced landed in Sweden on 9 October 1943 which was a year and a half after the G-2 entered service and 6 weeks after a BF-109G-6. (Which was a new production aircraft at the time.)
The Navalized BF-109T-1/2 also remained in service until the summer of 1944 with 11./JG 11 in Norway

Romania was still using the BF-109E In June 1942.