P-40 vs. ME-109

[HoHun]

Hi Claidemore,

>In one of the Soviet P40 pilot interviews he goes on quite a bit about the interviewers 'obsession' with max speed. He points out that in combat max speed was seldom attained,(when it was it was usually in a dive where the P40 held an advantage) and wasn't a critical factor in a fight.

Hm, to give a rough indication: At 6 km and up, the Me 109G-2 probably cruised around 50 km/h faster than the P-40 could do at emergency power. This limits the tactical options of the P-40 pilot considerably ...

In fact, if there is one universal, overriding trend in WW2 fighter design, it's the trend towards higher top speeds at the expense of manoeuvrability. Obviously, top speed was what combat experience showed to be critical, even if the mileage of individual pilots varied (In assessing the interview, you also have to take into account that a pilot necessarily focuses on the strengths of his aircraft because that's what he needs to do to survive.)

"Though this varied depending on the specific variants, the P-40 usually had an edge over Bf 109 in horizontal maneuverability"

With two aircraft using a very similar airfoil, having a similar wing loading and a similar power output, I really wonder how the one that's heavier than its opponent by a ton got the reputation of superior "horizontal maneurability" No way!

Regards,

Henning (HoHun)

 

[claidemore]

Hi Henning,

I get a wingloading of 35.5 lbs/sq ft for P40k (Kittyhawk III)and 39 lbs for a 109G2. Thats figuring 6800 lbs for the 109 and 8400 for the P40, 1600lbs heavier (pretty close to a ton). I've seen lighter and heavier weights for the 109 even on the same document.
I get a P40K @1325hp and 109G2 @1335 (1.42ata) and 1455 takeoff power.
Haven't found a stall speed for P40 yet.

I might be mistaken about the RAE tests, I can't seem to find it now, and I might be confusing them with the Rechlin tests against a Curtiss,Spit and Hurricane. Don't know if the Curtiss referred to is a Hawk 75 (radial) or a Tomahawk. In any case, the Rechlin test says:

Before turning fights with the Bf 109 E type, it must be noted in every case, that all three foreign planes have significantly smaller turning circles and turning times.

 

[Glider]

This was a radial Curtis

 

[claidemore]

This was a radial Curtis

Agreed. I checked the date on the Rechlin test, and it's almost impossible for Luftwaffe to have a Hawk 81 or Tomahawk at that time. Has to be a French Hawk 75A.

 

[renrich]

Some info on the P40, all in the Med. Flew 67059 sorties, had 553 losses, not a bad ratio but intensity of combat probably not as great as in Europe. The P40 had 592 kills in the Med, so losses to kills were about even. These, I believe, are all sorties by AAF pilots.

 

[Soren]

Hi Henning,

I get a wingloading of 35.5 lbs/sq ft for P40k (Kittyhawk III)and 39 lbs for a 109G2. Thats figuring 6800 lbs for the 109 and 8400 for the P40, 1600lbs heavier (pretty close to a ton). I've seen lighter and heavier weights for the 109 even on the same document.

The 109 has got automatic LE slats, that's the deciding difference, hence why it turns much better than the P-40. Marseilles for one shot down quite a few Spitfires, Hurricanes P-40's in turn fights, cause he was not afraid of the slats unlike the British test pilots and some of the early Emil pilots.

I get a P40K @1325hp and 109G2 @1335 (1.42ata) and 1455 takeoff power.

Hence why the Bf-109 has a MUCH better sustained turn rate.

As for the stall speed of the 109G-2, it's 145 km/h clean flaps gear up.

I might be mistaken about the RAE tests, I can't seem to find it now, and I might be confusing them with the Rechlin tests against a Curtiss,Spit and Hurricane. Don't know if the Curtiss referred to is a Hawk 75 (radial) or a Tomahawk. In any case, the Rechlin test says:

And it must be stated that this test was not only carried out with an Emil which had frequent problems with its slats jamming and behaving oddly in flight, it was also in 1940, a period where there weren't many experienced pilots in the type. The German test pilot in this case was as vary about the slats as the British test pilots were when they flew it.

The problems only occured in tight turns though, and not in a slow speed straight stall, in which the slats on the Emil worked very well. The stall speed of the Emil is 61 mph flaps gear down and 75 mph clean gear flaps up.

All the problems with the slats were addressed with the introduction of the F series, and from there'on the Bf-109 could did comfortably engage in turning fights with the Spitfire and win.


Erwin Leykauf, German fighter pilot, 33 victories.
"During what was later called the 'Battle of Britain', we flew the Messerschmitt Bf109E. The essential difference from the Spitfire Mark I flown at that time by the RAF was that the Spitfire was less manoeuvrable in the rolling plane. With its shorter wings (2 metres less wingspan) and its square-tipped wings, the Bf 109 was more manoeuvrable and slightly faster. (It is of interest that the English later on clipped the wings of the Spitfire.)
For us, the more experienced pilots, real manoeuvring only started when the slats were out. For this reason it is possible to find pilots from that period (1940) who will tell you that the Spitfire turned better than the Bf 109. That is not true. I myself had many dogfights with Spitfires and I could always out-turn them. This is how I shot down six of them."

Walter Wolfrum, German fighter ace. 137 victories.
"Unexperienced pilots hesitated to turn tight, bacause the plane shook violently when the slats deployed. I realised, though, that because of the slats the plane's stalling characteristics were much better than in comparable Allied planes that I got to fly. Even though you may doubt it, I knew the Bf109 could manouver better in turnfight than LaGG, Yak or even Spitfire."

Herbert Kaiser, German fighter ace. 68 victories.
"Personally, I met RAF over Dunkirk. During this battle not a single Spitfire or Hurricane turned tighter than my plane. I found that the Bf 109 E was faster, possessed a higher rate of climb, but was somewhat less manouverable than the RAF fighters. Nevertheless, during the campaign, no Spitfire or Hurricane ever turned inside my plane, and after the war the RAF admitted the loss of 450 Hurricanes and Spitfires during the Battle of France." In the desert there were only a few Spitfires, and we were afraid of those because of their reputation from the Battle of Britain. But after we shot a couple of them down, our confusion was gone."

Pierre Clostermann, Spitfire pilot.
"I tried to fire on a '109' that I spotted in the chaos. Not possible, I couldn't get the correct angle. My plane juddered on the edge of a stall. It was comforting that the Spitfire turned better than the '109'! Certainly at high speed - but not at low speed."

 

[slaterat]

I can find hundreds of quotes of Spitfires and Hurricanes easily outurning
109s. I can also find quotes from German aces saying they never turned against spits or Hurricanes. Both German and RAF testing confirmed that the 109 was inferior in the turn.

Slaterat

 

[Elvis]

Watched the feature on the P-40 I referred to earlier, that had Col Pay and Bobby Gibbes in it.
According to an interview of Gibbes, upon the unveiling of Pay's (then) newly restored P-40 (Gibbes attended the ceremony), Gibbes said the P-40 had better dive speed than a Spit, and (when flown properly) could turn with the Spit.
Considering how good of a showing the Spit made against the 109, it could be said that the P-40 could've had similar results against the 109 that the Spitfire did.
Gibbes also mentioned that the six 50's of the P-40 was better armorment than the eight 303's of the Spit.
He also talked quite highly of the 109, but didn't mention any comparitives between it and the P-40.


Elvis

 

[Kurfürst]

Soviet figures for P-40, 109G turn times, 1000m.

P-40C 18 secs
P-40E 19,2 secs
Bf 109F-2 19,6 secs (this one was in pretty rough shape, so..)
Bf 109G-2 20 secs, 290 m radius

Bf 109E
from Mtt report, 0 m : 18,92 secs, 203 m
from Baubeschreibung für das Flugzeugmuster Messerschmitt Me 109 mit DB 601 : 170 m w/o flaps, 125 meter with flaps. Turn time not given.

Messerschmitt Me. 109 Handling and Manoeuvrability Tests BY M. B. MORGAN, M.A. and D. E. MORRIS, B.SC.

When the Me.109 was following the Hurricane or Spitfire, it was found that our aircraft turned inside the Me.109 without difficulty when flown by determined pilots who were not afraid to pull their aircraft round hard in a tight turn. In a surprisingly large number of cases, however, the Me. 109 succeeded in keeping on the tail of the Spitfire or Hurricane during these turning tests, merely because our Pilots would not tighten up the turn suficiently from fear of stalling and spinning.

...

The gentle stall and good control under g are of some importance, as they enable the pilot to get the most out of the aircraft in a circling dog-fight by flying very near the stall. As mentioned in section 5.1, the Me.109 pilot succeeded in keeping on the tail of the Spitfire in many cases, despite the latter aircraft's superior turning performance, because a number of then Spitfire pilots failed to tighten up the turn sufficiently. If the stick is pulled back too far on the Spitfire in a tight turn, the aircraft may stall rather violently, flick over on to its back, and spin. Knowledge of this undoubtedly deters the pilot from tightening his turn when being chased, particularly if he is not very experienced.

 

[Elvis]

kurfurst,

Thanks for the informative post, but the only thing I see that whole report really saying is that unexperienced pilots were most likely easier target for more experienced pilots, because they weren't as secure in the performance of their planes.
Kinda funny, because that conclusion would seem like "common knowledge", but now they have PROOF.

Thanks for the turning figures between the 109 and the P-40, as well.



Elvis

 

[Kurfürst]

Well, obviously between two identical planes its pilots experience that matters, between two different planes however, stall characteristics can be important, ie. how easy it is to push the aircraft to its limits, or in different words, what are the limits for pilots of different skills.

Good stall characteristics and foolproof handling was one of the 109s fortes for sure. The Spitfire was not so ideal in this respect because of the utter sensitivity of the controls in pitch. I dont know about the P40 in this regard.

 

[HoHun]

Hi Kurfürst,

>Soviet figures for P-40, 109G turn times, 1000m.

>P-40C 18 secs
>P-40E 19,2 secs

Ah, these are the figures I had in mind when I mentioned the P-40 being "a ton heavier".

I've attached the scan of the Soviet data ...

My calculations show the circle time for the Me 109G-2 to be 19.6 seconds at 2600 rpm/1.3 ata compared to the Soviet 20 s.

However, the circle time for the P-40C I calculate as 19.6 s, which is not surprising considering its lower power and higher weight, and the P-40E - which adds another 450 kg of mass - in my calculation comes out at 22.7 s at 3000 rpm/44" Hg, which is worlds apart from the 19.2 s given in the Soviet table.

To give an idea of the proportion: Even if I use the engine power data for the V-1710-81 at 3000 rpm/57" Hg, which yields about 200 HP more at 1 km than the V-1710-39 of the P-40E at 3000 rpm/44" Hg, I still get a circle time of 20.8 s ...

Accordingly, I don't consider the Soviet data on the P-40 variants realistic. Weight really means something in a turn!

Regards,

Henning (HoHun)

 

[claidemore]

Is the Soviet data tested or calculated?

Claidemore

 

[HoHun]

Hi Claidemore,

>Is the Soviet data tested or calculated?

I know they did quite a bit of turn rate testing, but if that applies to the P-40s listed in the scan, I don't know.

The Soviet data can be be a bit inconsistent at times - for example, I couldn't figure out what their top speed figures mean, as the altitudes given don't match the altitudes you'll find in US documents on aircraft and engine.

With regard to the Soviet turn rate data, there is a set of diagrams listing quite a number of fighter aircraft, but if you use two of these sets to establish the weight of the listed fighters, you'll end up with two different figures for half of the types.

Accordingly, my confidence in the informative content of these Soviet tables and diagrams is somewhat limited.

Regards,

Henning (HoHun)

 

[Hunter368]

Agreed, I have always found Russian test results........questionable.

 

[claidemore]

There's a few things I've learned about the Soviets and their fighters.

Soviets were always concerned with maneuverability, and as you pointed out HoHun, they did a lot of turn time tests. Most of the pages describing the various Soviet pilots at Alexandre Savines' Russian Aviation Museum website include turn time figures. Interestingly,(and dissapointingly) they don't list turn times for the P40 on this site. They list the P40C at 3424kb (7532lbs) loaded weight which is a little higher than some sources, but have the P40K at 8400 lbs, which agrees with other sources. I found the figures listed on this site to be pretty reliable when I was researching the Yaks.

Russian Aviation Museum

The Russians also were notorious for burning out engines in their lend-lease fighters, operating them at max power continuously. This is often quoted as part of the reason for their success with the P39.

I know that some of the P40s in Soviet service had guns removed or replaced, though the practice was not universal. Don't know if those two things might factor into the turn time numbers they got or not.

Here's a little quote about the P40s in Soviet service from the 'lend lease site';

In conclusion, one fact should be noted: three Twice HSU (of 27) in Soviet aviation fought in the Kittyhawk: B. F. Safonov, P. A. Pokryshev (22 personal victories and 7 in group), and M. V. Kuznetsov (22 + 6). Pokryshev and Kuznetsov flew the Kittyhawk for more than a year. Many pilots became aces and HSU while flying the P-40, achieving good combat scores. A number of regiments gained their guards status while flying the P-40. On the whole this aircraft fought well, though the conceptual errors that were built into it significantly reduced the sphere of its effective employment.

And a couple quotes from Nikolai Golodnikov, who flew P40s with 2GvSAP

We completely abandoned the defensive circle as soon as they re-equipped us with the P-40. The P-40 was equal to the Bf-109F and therefore we had no reason to resort to the defensive circle. No reason at all.

The Tomahawk and Kittyhawk had different armaments. The Tomahawk had four machine guns—two synchronized heavy machine guns in the nose and a pair in each wing. I have already forgotten the caliber of the wing-mounted machine guns, because we immediately removed them. Perhaps they were standard [they were .30 caliber—JG].
The Kittyhawk did not have [nose-mounted] synchronized machine guns. It had only six (three in each) wing-mounted heavy machine guns. We removed two of these machine guns immediately, leaving four.

Even during the war I recognized the fact that the Allies considered it inadvisable and almost impossible to conduct aerial combat in the P-40. We considered the P-40 to be a full-fledged fighter plane.
When we began to use the P-40, we immediately discovered two deficiencies that reduced its value as a fighter. 1. The P-40 was a "slug" in acceleration, rather slow to acquire speed. This weak dynamic resulted in a low combat speed. It had trouble maintaining the speed required for combat. Speed is essential for a fighter. 2. It was weak in the vertical, especially the Tomahawk.
We compensated for poor acceleration by holding the engine at higher revolutions and cruising at a higher speed. We corrected the second deficiency by removing a pair of machine guns. That was all. The fighter came up to par.
Now everything depended on you, the pilot. Keep your head! And work the stick intensively.
It is true that because of our unforeseen operating regime the engines had a limit of about 50 hours, and often less. Normally an engine might last 35 hours and then it was replaced.

 

[Zarathos]

Soviets were always concerned with maneuverability

May I disagree? Since 1938, when Polikarpow screwed the I-180 and new constructors started to create fighters, Soviet tactics turned away from manoeuvrability. They were more concered since then with speed. And even pre-1938 Soviets were not making "more manoeuvrable" fighters, but they followed the concept of two fighters: interceptor and dogfighter (duo I-16/I-15).

Shortly pre-war it changed and Russians started to make faster and faster fighters at all cost - best example is Yak-3 which was the fastest USSR fighter, but it was so light, that it had tendece to fall apart at higher g-forces. Of course, Russians were interested in turn times and done a lot of tests, but Germans done the same with captured airplanes, and Brits, and US. Find weak spot and tech fighter pilot to exploit them. I have somewhere notes from Polikarpov fighter tactic book, and most manoeuvers were based around high-speed and vertical manoeuvers, not around horisontal manoeuvrability.

I found the figures listed on this site to be pretty reliable when I was researching the Yaks.

Russian Aviation Museum

Yes, it is quite good, but it's better to check the data presented there, because some of it is not taking into consideration some... problems of Russian tech. For example - the max speed of Ła-5FN on sealevel is listed with boost, while M-82 engines were not able to engage the boost at such low altitueds. Another example is 655 km/h as max speed of Yak-3. It's also true, but at such speeds any turn with g-force higher then 4g if I good remember resulted in wings flying in one direction and hull in another.

Not to mention, that both max speeds were for prototype or test fighters which were (usualy) made properly. Normal fighters had in most cases troubles with reaching those numbers.

And so on...

 

[HoHun]

Hi Claidemore,

>The Russians also were notorious for burning out engines in their lend-lease fighters, operating them at max power continuously. This is often quoted as part of the reason for their success with the P39.

Hm, I've heard about that, too, and it seems to match Allied practice in the Pacific (though it was not really maximum power, but actually long-term use of power settings above "maximum continuous"). However, I also remember an interview with a Soviet P-39 pilot who said that he only once or twice used the full 57" Hg boost pressure of his Allison ...

>I know that some of the P40s in Soviet service had guns removed or replaced, though the practice was not universal.

It would make sense ... though I'm not sure there was enough of a weight saving to justify the high turn rates listed in the scan I posted.

The P-40C would need to be down to about 3100 kg to achieve the 18 s for 360 degrees at 1000 m figure ... the P-40E to 3635 kg. That's a 290 kg for the P-40C and a 205 kg saving for the P-40E compared to the weights listed above.

From a P-40N weight and balance chart, it had 4 12.7 mm MGs for a total of 320 lbs and an ammunition supply of 940 rounds for a total of 280 lbs. If the weights and ammunition capacity per gun were the same of the P-40E, the Soviets would have saved 300 lbs by removing one pair of machine guns and their ammo - or 136 kg. That's not yet enough to reach our target of 205 kg, but of course, they might have tested with a reduced fuel load, too - perhaps that was actually representative for the way they flew in combat, too.

Regards,

Henning (HoHun)

 

[Soren]

Did you use a CLmax of 1.70 for the Bf-109 in your calculations HoHun ?

I'm asking since this is the tested value for the F series.

With that in mind it's quite clear than the Bf-109 G-2 at 2,890 kg easily out-turns the P-40C, E M.

 

[Soren]

The P-40 also featured an airfoil with a slightly lower Clmax than the NACA R2 (Modified Clark Y airfoil) used by the 109. This airfoil was the same as the Spitfire's, the NACA 2200 series, in this case 2215 at the root and 2209 at the tips.