Peter Gunn
Master Sergeant
Also wouldn't it be more fair/factual if we're going with 44 TOTAL Airacobras lost with how many TOTAL Zeros were lost, if that number were possible to find? I mean, apples to apples right?
XP-39 II - The Groundhog Day Thread (3 Viewers)
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Hello XBe02Drvr,
The Sturmovik was just one illustration of the idea. There are a bunch of others that were done.
The Me 262 had a much more drastic change to its wing planform to hang a pair of rather heavy engines further back to maintain CoG.
The FW 200 Condor in later versions had swept outer wing sections presumably for the same type of CoG issue.
The P-39 had a three spar wing. The objective as I see it would be to move the Center of Lift about 3.5% or 4% MAC (about 3.22 inches) aft. The problem though is that a bit over 1000 pounds of structure would also be moving so the calculations are obviously not quite that simple. The benefit is that the fuel tanks would also be moving which means that a disposable load is now further back from the CoG and would balance out the disposable loads in the nose.
If there are some torsional loads to be considered, I believe they could be compensated for by reducing the maximum G load from the standard 8/12 G down to something like 7.5/11.25 G as for other aircraft that gained some weight from their initial designs. Even the last versions of the Airacobra had not gained substantial weight from the initial service versions.
I believe the best idea would have been a much more thorough redesign instead of a patch job when the P-39 lost its interceptor mission.
- Ivan.
FLYBOYJ
"THE GREAT GAZOO"
Yes - my point. If we're just talking air-to-air, it was a draw. According to the posted numbers 15 Zeros and 15 P-39s were lost air-to-air but we don't know if additional Zeros were lost to other causes.
So am I, someone doesn't know what hearsay means, a pilots report is not hearsay, someone saying "I heard a pilot say" is hearsay. Pilots reports on the P-39 including reports on those who died in non operational missions in UK, played a part in them all being shipped to Russia. An individual pilots report may or maynot be in error, when many pilots report the same thing only a fool would discount it.
hearsay
[ˈhɪəseɪ]
NOUN
- information received from other people which cannot be substantiated; rumour.
the report of another person's words by a witness, which is usually disallowed as evidence in a court of law.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
Exactly - cull the P-39 operational losses out of the total number and it becomes a wash.
ONLY include the P-39's operational losses in the total number if the A6M group's operational losses can be added.
P-39 Expert
Non-Expert
In the 19:35 comments "they were too heavy and lacked a supercharger". Everyone knew they were too heavy, why didn't they reduce the weight? And the lack of a supercharger is another myth that has been perpetuated for 75 years.
Reluctant Poster
Tech Sergeant
- 1,776
- Dec 6, 2006
Late model P-51 B and Cs switched to the -7. The difference between the two versions was the supercharger drive ratio. The -7 used lower ratios and therefore developed more HP at lower altitudes at the expense of high altitude performance.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
And the original point of the P-51B/P-51D comparison, was that the P-51D (empty) was heavier than the P-51B (empty), yet had better performance - contrary to someone's insistence that a lighter P-39 would have had better performance.
So again: weight alone is not the magic solution to a type's performance.
So again: weight alone is not the magic solution to a type's performance.
P-39 Expert
Non-Expert
Please expand above.
P-39 Expert
Non-Expert
And nobody ever notes the attrition of the best Japanese pilots by the P-39, P-40 and F4F. The P-39 and P-40 were still the most numerous AAF fighters in NG until Sept '43. The newer AAF pilots were much better trained than the earlier pilots, and the Japanese replacements were much worse in their training. The P-38, Corsair and Hellcat pilots were facing declining competition.
Anybody else getting a headache in here?
GregP
Major
As far as I know, there are two ways to calculate kill-to-loss ratio:
1) Own losses in air-to-air combat alone against air-to-air victories, and
2) All combat losses against all victories.
The real issue is that the USAAF and the USN / USMC do NOT save the data the same way.
The Navy breaks out losses as losses on action sorties and losses to non-action missions. Losses on action sorties are losses to: 1) Enemy aircraft, 2) losses to AAA, and 3) Operational losses on combat mission unrelated to combat (ran out of fuel, engine malfunction, mid-air collision, post a prop). Losses on non-action sorties are losses: 1) Losses on Ship (carrier sank) or Ground, and 2) Losses on Other Flights (such as repositioning flights, maintenance flights, etc.).
The USAAC/F, on the other hand, just tracks all Combat losses, but they break victories up into: 1) Air-to-air, and 2) Ground.
By way of example, take the F6F Hellcat: Air-to-air: 270 air-to-air losses; 5,163 kills = 19.1 : 1 in air-to-air combat. But, if you look at ALL combat losses, you get: 1,163 losses against 5,163 kills = 4.44 : 1 overall.
If you look at the P-51 Mustang, we see: 2,520 combat losses, 4,950 air-to-air victories = 1.96 : 1 in air-to-air combat. But, the P-51 also had 4,131 ground kills. If you add air and ground kills, you get 9,081 kills. So, we have 2,520 combat losses against 9,081 kill = 3.60 : 1 kill-to-loss combat total.
We can't break out air-to-air losses for the P-51 and we can't break out air versus ground kills for the F6F. So, the only real comparison is total ratio: F6F = 4.44 : 1 and P-51 =3.60 : 1. The only thing we CAN say is that the F6F kills can't have too many on the ground versus the P-51's total because the ocean won't support stationary airplanes. Therefore, there are many fewer ground kills in the case of the F6F. But, we can't say how many.
By the way, the data for the P-51 is ETO-only from Ray Wagner's American Combat Planes. The data for the F6F is from Naval Combat Statistics of World War II.
I show the P-39 as 107 combat losses against 32 kills for a kill-to-loss ratio of 0.3 : 1. But, that is for the ETO only. I don't have the P-39's Pacific numbers and am not sure where to find them.
1) Own losses in air-to-air combat alone against air-to-air victories, and
2) All combat losses against all victories.
The real issue is that the USAAF and the USN / USMC do NOT save the data the same way.
The Navy breaks out losses as losses on action sorties and losses to non-action missions. Losses on action sorties are losses to: 1) Enemy aircraft, 2) losses to AAA, and 3) Operational losses on combat mission unrelated to combat (ran out of fuel, engine malfunction, mid-air collision, post a prop). Losses on non-action sorties are losses: 1) Losses on Ship (carrier sank) or Ground, and 2) Losses on Other Flights (such as repositioning flights, maintenance flights, etc.).
The USAAC/F, on the other hand, just tracks all Combat losses, but they break victories up into: 1) Air-to-air, and 2) Ground.
By way of example, take the F6F Hellcat: Air-to-air: 270 air-to-air losses; 5,163 kills = 19.1 : 1 in air-to-air combat. But, if you look at ALL combat losses, you get: 1,163 losses against 5,163 kills = 4.44 : 1 overall.
If you look at the P-51 Mustang, we see: 2,520 combat losses, 4,950 air-to-air victories = 1.96 : 1 in air-to-air combat. But, the P-51 also had 4,131 ground kills. If you add air and ground kills, you get 9,081 kills. So, we have 2,520 combat losses against 9,081 kill = 3.60 : 1 kill-to-loss combat total.
We can't break out air-to-air losses for the P-51 and we can't break out air versus ground kills for the F6F. So, the only real comparison is total ratio: F6F = 4.44 : 1 and P-51 =3.60 : 1. The only thing we CAN say is that the F6F kills can't have too many on the ground versus the P-51's total because the ocean won't support stationary airplanes. Therefore, there are many fewer ground kills in the case of the F6F. But, we can't say how many.
By the way, the data for the P-51 is ETO-only from Ray Wagner's American Combat Planes. The data for the F6F is from Naval Combat Statistics of World War II.
I show the P-39 as 107 combat losses against 32 kills for a kill-to-loss ratio of 0.3 : 1. But, that is for the ETO only. I don't have the P-39's Pacific numbers and am not sure where to find them.
P-39 Expert,
I heard / noticed that as well. Not sure if the guy narrating the film is a pilot or not. Did you notice how he said the P-38 had a supercharger? I know of the supercharger myth surrounding these engines, but when he mentioned that the 38 had a supercharger, and the 39 did not, I assumed he meant turbo, or turbosupercharger for period speak.
"Testing was factual and comparable. Pilot reports were hearsay and opinion." P-39 Expert
This comment is astounding. If testing was so factual and comparable, why did it get repeated so often? Why were there so many comments about engines running rough, large sections of rebuilt aircraft, and no manual?
If pilot reports were hearsay, why did the guys who were running the war want them? So the first guy who reported a Me-262, or long nosed FW-190, or a Me-109 with a bigger spinner were all speaking hearsay? I fought a non-export version of another countries primary fighter. I was talked to before the fight by several different people, and after the fight I did a AAR (After Action Report) and received several phone calls plus more debriefings by Intel. I was only a 4 ship flight lead, not an IP / Test Pilot. I wonder why they (Intel) wanted my opinion / experience so badly.
You also mentioned Chuck Yeagers fondness of the P-39. Did he fly it only in training, where the CG was most likely as far forward as could be made for the safety of new / novice fighter pilots? Have you ever reached out to him to ask his opinion on whether it would have made him an ace like the P-51 did? Be careful, he doesn't tolerate what he deems silly questions very well.
You never replied to my earlier, rather long post (594) so I don't hold much hope here either but will say it regardless. There are aviation mechanics, pilots, engineers who are mechanics and pilots, all whose experience with aircraft, military and otherwise, is quite large. They have stated and made known their collective background, experience yet you don't believe or give them due credit.
I have to ask, what is your aviation / mechanical experience? Have you sat down with and discussed P-39s with the guys who flew it, or other fighters in WW2? Have you worked on / restored / raced any as members here have? Have you taken flight lessons? Or are you like the majority of us gleaning through piles of old information, often with contradictory "facts", trying to sort out what really happened and why? There is a blend of both on here, and you aren't giving ANY credit to the other group or anyone who doesn't agree with your assumptions. Be careful, that's not the way to gain credibility.
Cheers,
Biff
And by the way, pilot reports are not even close to the definition of hearsay.
That is what Claringbold writes, but not clearly; it can be misconstrued that these are the total combat losses for both sides during the campaign/ time period. That is not the case, for both sides lost P-39's and Zero's to enemy action on missions where they didn't meet in combat.
That is the total losses in the combats in which P-39's met Zero's in combat. So 44 P-39's lost to all causes against 15 Zero's lost to all causes (all causes in this case being P-39's).
GregP
Major
And a "pilot report" is not the same thing as a "hangar story" to impress the locals many years after active duty. Active-duty pilot reports are solicited to give other active-duty pilots an edge in combat. If they are "inflated" or false in any way, everyone will know when they try the suggested tactic(s) in the pilot report, so nobody gives false active-duty pilot reports, even the show-off guys.
On the other hand, very specific numbers recalled 50 years later are suspect since our memories are generally rose-colored. I'd not trust an old WWII pilot who thought the best climb speed for some fighter was some exact number, but I DO trust him when he says that he never reached his airplane's top speed on a combat mission unless he was in a dive, because who wants to run their engine at absolute full power when you are 500 miles from home over hostile territory with a currently-good-running engine? That's why I believe the old guys when they say combat speeds were in the 250 - 350 mph range unless the fight was a descending chase. When combat joined, they went to military power and mostly only used WEP if their life was in danger, not just to get an offensive kill. There were exceptions, but not very many after the crew chief reamed the pilot for breaking the throttle gate wire without a good reason. That sometimes meant an engine change for the crew, and they would not be happy about it.
Luckily, today's jets don't have quite the issue the WWII planes did. They routinely go into afterburner (and usually track hot temperature cycles) on takeoff, whereas NOBODY used (or uses) WEP for takeoff in a piston fighter. There might not be enough rudder or aileron to stay on the runway if they did. Of course, we also don't have 150 performance number fuel today, either, so nobody runs the old engines at what used to be WEP.
On the other hand, very specific numbers recalled 50 years later are suspect since our memories are generally rose-colored. I'd not trust an old WWII pilot who thought the best climb speed for some fighter was some exact number, but I DO trust him when he says that he never reached his airplane's top speed on a combat mission unless he was in a dive, because who wants to run their engine at absolute full power when you are 500 miles from home over hostile territory with a currently-good-running engine? That's why I believe the old guys when they say combat speeds were in the 250 - 350 mph range unless the fight was a descending chase. When combat joined, they went to military power and mostly only used WEP if their life was in danger, not just to get an offensive kill. There were exceptions, but not very many after the crew chief reamed the pilot for breaking the throttle gate wire without a good reason. That sometimes meant an engine change for the crew, and they would not be happy about it.
Luckily, today's jets don't have quite the issue the WWII planes did. They routinely go into afterburner (and usually track hot temperature cycles) on takeoff, whereas NOBODY used (or uses) WEP for takeoff in a piston fighter. There might not be enough rudder or aileron to stay on the runway if they did. Of course, we also don't have 150 performance number fuel today, either, so nobody runs the old engines at what used to be WEP.
FLYBOYJ
"THE GREAT GAZOO"
Not in late 1942/ early 1943 and it depends where we are talking. Many seasoned JN pilots were lost at Midway and that attrition never fully recovered. JAAF pilots were a different story. The P-39, P-40 and F4F over the Solomons barely scraped over a 1 to 1 kill/ claim ratio. Once the P-38 came on scene scores jumped. This is well documented in the 39th and 80th FS histories as well as other units that gave up their P-39s for P-38s. With that said, the P-39 did serve a purpose, it did hold the line but we weren't going to win the war with a 1:1 kill ratio.
Reluctant Poster
Tech Sergeant
- 1,776
- Dec 6, 2006
These are not kills they are claims. There is usually a large difference.
Without the racks, the P-51B was probably faster, not slower. With racks on, the positions switched. P-51D used more streamlined racks, 4 mph cost vs. 12 mph on the B.
So many variables! Nothing's simple anymore!
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