P-39 D Aircobra vs. Me-109

[Soren]

Some valid points JoeB, no doubt, but I'm not talking about claims, I'm talking about confirmed kills. The confirmation criteria layed down by the OKL was followed strictly until the very end, hence many actual kills stayed claims and weren't confirmed, esp. near the end.



When it comes to being accurate no'one is quite as thurough as the Germans, they're perfectionists.

[drgondog]

Some valid points JoeB, no doubt, but I'm not talking about claims, I'm talking about confirmed kills. The confirmation criteria layed down by the OKL was followed strictly until the very end, hence many actual kills stayed claims and weren't confirmed, esp. near the end.

When it comes to being accurate no'one is quite as thurough as the Germans, they're perfectionists.

Soren, meticulous they were - no question. Having said that I have spent a lot of time cross referencing 'kills vs losses' for the 355th and the 8th AF.

I would offer one case for thought. If we believe in the thoroughness of Dr. Prien's work (which I do) and by extrapolation Tony Wood's recounting of LW awards then the mission of April 24, 1944 is an example where the LW awards were nearly 50% in error -despite the rigor of the process.

They 'overawarded' the Mustang scores by nearly 3:1 in total and 4:1 with respect to fighter vs fighter scores. I'm not yet sure what the 8th AF overclaim ratio is because Dr. Prien's works don't break out losses to fighters vs bombers. The LW process 'overawarded' the bombers losses 27 by about 2:1 and that includes the 9 ships that landed in Switzerland, landed in Sweden, ditched in Channel and went down to flak.

Interestingly enough the JG11 claims of three Mustangs in Mannheim area matches exactly what the actual losses were in that area.

But take the 11 Mustangs awarded to III./JG26, JG3 and JG27 for the Augsburg Muhldorf, Oberpfaffenhoffen area for example. 8 were awarded on basis of film, three more with no reference, presumably witness, but only four were lost to fighters. Two were lost to mid air collisions with Me 110s that they shot down - but those claims are not even on the rolls, presumably because there were no surviving witnesses?

I have the details, thanks to help from Eric, and I presented the 355th awards and 357th awards as well as the 1st BD actual losses for all causes on Mike Williams site if you want to look at them.

To summarize - I KNOW the LW claims process was a good one, so was 8th AF, and I know that both awards systems produced more awards by some considerable margin than actaul losses experienced by the other side.

I found one of the root causes via Dr Prien, who confirmed that if a Germand aircraft crash landed due to an air battle, it wasn't on the rolls as 'destroyed' unless it was in fact salvaged on the spot. More likely it wouldn't show up as anything but '60% damaged' and might or might not reference whether it was flak or air damage.

I know another source of a faulty award was the dreaded example of 'The Fw was last seen spinning out of control and he could not have recovered" - well some did. etc, etc so the 8th AF awards systems were faulty in that respect as well as awarding a 'destroyed' for an a/c they forced to crash land - but later repaired by Germans.

At any rate neither was close to infallible.

Regards,

Bill

[JoeB]

but I'm not talking about claims, I'm talking about confirmed kills..

So I am, pardon any inprecision on my part between the term 'claim' and 'confirmed kill'; but both in the final analysis are the perception of *one side* of its successes, to be distinguished from victories actually cross referenced in the other side's loss records. When I say 'claim accuracy' I mean 'confirmed victory accuracy', if you prefer that term.

See drgondog's post, but another example is victories awarded to Me-262 pilots against Allied fighters in '44-45: highly overstated according to Allied records, as apparent in published sources, apparently more than in the cases drgondog mentions. And note, my previous example of the 1943 P-39 case (7 real losses, 20 victories) is also based on the Tony Woods lists.

Also while we could quibble about what exactly *was* a 'confirmed kill' in the dying days of the Luftwaffe, many books and other sources quote these quite overstated German fighter pilot accounts of victories in '44-45, so they were not 'raw claims' which were simply disallowed and forgotten: people still draw (sometimes misguided) conclusions based on them even today.

But again, this contrasts sharply with remarkable German claim ('confirmed victory') accuracy at times in the war, and at other times their accuracy was neither especially accurate nor inaccurate: it varied.

And the key point again is that the nominal procedure of confirming claims did not determine the claim accuracy. Again, the Soviets in Korea on paper followed a procedure similar to the Luftwaffe's in WWII: required two pilots testimony, gun camera, and statement of allies (1950-51) or own wreck team results ('52-53) of the crash and still their 'cofirmed victories' exceeded UN air combat losses by a factor of around 6; and that's based on pretty extensive examination of particular Soviet credits, knowing the places and times, v. original US records, which almost always show a combat *did* happen at that place and time, but pretty consistently fewer losses, and corroborated in all kinds of other records (those of individual a/c, sdn maintenance records, etc etc) so not much doubt about it. I'm not directly comparing the Soviet and German claim accuracies, I'm just saying the procedure on paper didn't entirely determine the accuracy, for *any* AF.

Joe

[claidemore]

On the topic of P39s.

Here is an interesting site that gives some clues as to why the Soviets might have liked the P39.

Airacobra I for RAF, P-400

One advantage the 109 and 190 had over all Soviet fighters, was dive speed. Soviet pilots complained that the German pilots could always disengage and dive away, and there wasn't a lot they could do about it.

P39's could dive. 836 kmh(535 mph) according to the pilots handbook for the P39Q. Max dive speed for 109G2 (according to Finnish manual) is 750 kph.

[Soren]

One other advantage the BF109 & FW190 also enjoyed was much better performance over the whole height band. Additionally the FW190 enjoyed a huge advantage in agility at high speed, being able to pull excruciatingly high G pull outs. (But this was true against all other Allied fighters as-well)

[claidemore]

Was looking at some P39D stats. Never gave this plane a lot of thought before, but it seems like it wasn't quite the turkey it was often made out to be.

Climb time to 5000 meters, 5 minutes, about the same as a 109G6.
Wingloading of 36.72 lbs/sq ft, compared to 42 lbs/sq ft in a 109G6.
Thrust to weight is much less than a G6, the 109 is much better in that regard. 6.8 lbs/hp compared to 5lbs/hp for the 109G6.
P39D dive speed, 836 compared to 750 in the 109
The roll rate was 75 degrees per second at 380 kmh.(according to Wikpedia, which I am finding has some surprisingly accurate information on WWII planes) Roll rate on 109's was about 1.5 second for 45 degrees at that speed (according to RAE tests). I have not found figures on how P39 would compare to FW190 roll rate. (I'm sure someone will assure us that the FW was superior. )
It's also noted that high speed controls were very light, enabling high speed pullout in a dive.
Can't remember where I saw it, but one source indicated a turning circle of 1000 ft.
Deceleration was poor as it was an aerodynamically 'clean' design.

Most of this info comes from the P39D pilots manual, some from various online sources.

[drgondog]

Was looking at some P39D stats. Never gave this plane a lot of thought before, but it seems like it wasn't quite the turkey it was often made out to be.

Climb time to 5000 meters, 5 minutes, about the same as a 109G6.
Wingloading of 36.72 lbs/sq ft, compared to 42 lbs/sq ft in a 109G6.
Thrust to weight is much less than a G6, the 109 is much better in that regard. 6.8 lbs/hp compared to 5lbs/hp for the 109G6.
P39D dive speed, 836 compared to 750 in the 109
The roll rate was 75 degrees per second at 380 kmh.(according to Wikpedia, which I am finding has some surprisingly accurate information on WWII planes) Roll rate on 109's was about 1.5 second for 45 degrees at that speed (according to RAE tests). I have not found figures on how P39 would compare to FW190 roll rate. (I'm sure someone will assure us that the FW was superior. )
It's also noted that high speed controls were very light, enabling high speed pullout in a dive.
Can't remember where I saw it, but one source indicated a turning circle of 1000 ft.
Deceleration was poor as it was an aerodynamically 'clean' design.

Most of this info comes from the P39D pilots manual, some from various online sources.

The P-39D, and ultimately the P-63 were great improvements over the early Iron Dogs.. It is hard to conceive any nationality pilot other than Russia that pick a P-39 over a 109 from F through K in a fight.. maybe the 63 had an edge somewhere but still doubt the equivalency to a comparable stage 109 like a G-10 or K-4 or even a 109G-6/AS

As to roll rate for Fw 190A-4 versus 51B vs P-38L here is aniteresting source - I can not vouch for root source data


P-38L Roll Chart

Briefly at 280 Mph at 400mph
Fw 190A-4 140/sec 80/sec
P51B 80/sec 85/sec
P-38L 90/sec 90/sec

This is for boosted ailerons on the 38

Take what you want out of this. IIRC the P-40 had a faster roll rate than the 51B and C but closer to P38L so not much real difference.. P-39 slightly lower which your figure seems to agree with. The 109 roll rate you posted seems too low even for 400mph where they were really stiff

[claidemore]

Here is a link with measurement of 109 roll rate.

http://www.spitfireperformance.com/bank45.gif

I know the Luft guys will say that is wrong, and that the 109 actually rolled much faster than anything but a 190, and the test is biased, etc etc, but i haven't seen any reports or charts that show that. That is the only actual measurement I have seen, but I'd love to see another one if anybody has one.

[Soren]

Bill,

The 190A-4 used to acquire those results suffered from improper aileron adjustment, the roll rate suffered and because of the premature stalling in turns this caused esp. the turn rate suffered badly.

The real roll rate of the FW-190A is at those speeds is 180 degree's pr. sec, VERY fast.

[Soren]

Here is a link with measurement of 109 roll rate.

http://www.spitfireperformance.com/bank45.gif

I know the Luft guys will say that is wrong, and that the 109 actually rolled much faster than anything but a 190, and the test is biased, etc etc, but i haven't seen any reports or charts that show that. That is the only actual measurement I have seen, but I'd love to see another one if anybody has one.

Oh give me a break!

The Bf-109 didn't pocess any exceptional roll rate, infact most Allied fighters pocessed an equal or better roll rate at high speed. Roll rate wasn't the BF109's advantage over its opponents, turn & climb performance was.

[Glider]

Bill,

The 190A-4 used to acquire those results suffered from improper aileron adjustment, the roll rate suffered and because of the premature stalling in turns this caused esp. the turn rate suffered badly.

Can I ask how you know this?

[Soren]

Yes you can Glider. You can read the whole report somewhere on the net, in this report it is clearly mentioned.

I have it on my stationary at home as-well though, so if you wait while I can present it instead.

[renrich]

Soren, don't know where your figures come from but I have a hard time believing a roll rate of 180 degrees per second for an FW.

[drgondog]

Bill,

The 190A-4 used to acquire those results suffered from improper aileron adjustment, the roll rate suffered and because of the premature stalling in turns this caused esp. the turn rate suffered badly.

The real roll rate of the FW-190A is at those speeds is 180 degree's pr. sec, VERY fast.

Soren - I recall that the Fw 190 (unspecified version) rolled close to 180, and in the same breath that was at medium speed and altitude and degraded as speed increased. My father's recollection was 'lot faster than 51', '51 better than 109' - all anecdotal with no rigor, just fly it.

Having said that I have yet to see a LW Flight test report performed by LW which has any documented Fw 190 Roll rates or Me 109s... other than the stuff in Mike Williams website from both RAF and USAAF documents. Futher, one of the references I recall was on the Fw 190A-3 in comparison with the P-51B, The Spitfire, The P-47C (and D-2) plus P-38F. I can't recall whether Kurfurst has such on his site (I know he has volumes of data regarding airspeed and climb for many versions)

I posted that website that had the roll rate versus airspeed above but I have not verified the source other than Lockheed (i.e where and what version of Fw 190).. but the relationship of the dramatic slowdown as function of airspeed is consistent with all test results I have seen on the Fw 190, so it seems reasonable.

Having said that it still exceeds all (the 51 and the 38L) at 250-280 TAS by very significant margin. Period.

What references do you draw on?

[Glider]

Yes you can Glider. You can read the whole report somewhere on the net, in this report it is clearly mentioned.

I have it on my stationary at home as-well though, so if you wait while I can present it instead.

I look forward to it. I have been digging around and turned this one up that might be of interest. It gives the 190 a 160 deg/sec which is pretty impressive.
Flight Performance of Fixed and ... - Google Book Search