How good a plane was the P-40, really?

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I should have added that Marsailles' combat tally was not to diminish the P-40, but was more of an observation of a pilot's ability to understand his adversary's weaknesses and exploit it.

And oddly enough, I had come across Marsailles' score when looking for other Allied types downed by Experten. It just happened that Marsailles was the leading killer of P-40s out of the lot.

In regards to the Bf109 series, I believe it was the Bf109G-2 that was the zenith of the type. Variants that were introduced beyind that, were bloated and constantly required engine improvements to offset the increasing drag/weight-penalties the 109 suffered from.
 
The 109F-2 and F-4 was kind of the 'ballerina', and it was Marseille's favorite type. Not as heavily armed or as fast as later 109s, but definitely the most agile and maneuverable, which meant that it had a better chance of evading damage if caught in a dogfight against a Kittyhawk, Spitfire, or Hurricane. Evidently the G2s were coming in with some engine problems, and Marseille maybe had a premonition of trouble as he resisted converting to them. It was in a G-2 that he experienced engine failure and died.

I agree with you though that the G-2 and I'd also say the G-4 seem like quite formidable fighters. Faster than the F-4s, better armored, and potentially more heavily armed. IIRC they could carry two external fuel tanks so that increased range, always an issue with the 109s.

The G-6 (in all it's many variations) was a lot faster but much heavier too. Less agile.
 
I am going to go through the P-40 lineage using Curtiss figures. Adjust as people see fit.


P-40 Tomahawk I gross weight 6807lbs (120 US gal fuel), 357mph at 15,000ft. Initial climb 3080fpm, 15,000ft 5.3min.
P-40B Tomahawk IIa - GW..........7352lbs (120 gal), top speed 352 mph at 15,000ft, initial climb 2860 fpm. 15,000 5.1 min ( I know, it doesn't work)
P-40C Tomahawk IIb - GW..........7504lbs,(120 gal), top speed 345 mph at 15,000ft, initial climb 2690 fpm(climb to 15,000ft not given)
P-40D Kittyhawk I - GW...............7787lbs, (120gal), top speed 359 mph at 15,000ft, initial climb 2580 fpm.
P-40E Kittyhawk I- GW.................7952lbs, (120gal), top speed 366 mph at 15,000ft, initial climb _____. 15,000ft 6.25min.*
P-40E Kittyhawk IA- GW..............8100lbs, (---gal), top speed 354 mph at 15,000ft, initial climb 2050fpm. **
P-40K Warhawk --- GW...............8300lbs, (120 gal), top speed 362 mph at 15,000ft, Climb at 5000ft was 2160fpm, Climb at 15,000ft/1650fpm.
P-40F Warhawk I -- GW,..............8509lbs, (120 gal), top speed 364 mph at 20,000ft, climb ___________.
P-40L Warhawk/Khawk II, GW...8120lbs, (120 gal), top speed 370 mph at 20,000ft, initial climb 3300 fpm.
P-40M Warhawk -- GW...............8319lbs, (120 gal), top speed 360 mph at 20,000ft, initial climb 2050 fpm. 15,000ft 7.2 min
P-40N Warhawk -- GW..............7740lbs, (??? gal), top speed 378 mph at 10,500ft, 15,000 6.7 min (stripped version, four guns, WEP)
P-40N-25 Warhawk - GW............8354lbs, (159gal), top speed 350 mph at 16,500ft, initial climb 2120fpm, 14,000ft in 7.3 min. (heavy FB version, six guns)

*Standard US performance figures for climb use military power for climb (3000rpm for the Allison) for 5 minutes and then max cruise (2600rpm for the Allison) for the rest of the duration of the climb and do not accurately reflect combat capability.
US often tested at standard altitudes like 15,000ft and not at the altitude that gave best performance (like 14,000ft or 16,000ft).

** I don't really know what was going on in the two different P-40E versions.

All weights are for standard Gross weight, clean with the 'standard' fuel load which is NOT full internal fuel. These are also the weights for a specific airframe pulled off the Curtiss line, The P40F for instance was 109lbs over guarantee weight. A few P-40s were up to 29lbs light, others were over. Any production aircraft could vary 2-3% in speed and still be accepted
I will also note than on the P-40Ls and the early P-40N they pulled one internal fuel tank out so the range really took a hit without the external tank, all figures do not include external tank. External tank could be worth 20mph on speed.
No information on if they tested clean or with brackets/braces.

A note on the P-40D,E and K, the change in critical altitude was change in the power rating from the earlier engines, They were allowed to use higher boost at lower altitude (not WEP) in military power and so made 1150hp at just under 12,000ft instead the 1040hp at 14,300ft for the earlier engines, however the newer engines would still make 1040hp at 14,300ft.
Some of this depended on exact intake manifolds and flame arresters/backfire screens.
If the pilots on the older airplanes used more than book boost (there were no pressure limiters) they could (and did) get the 1150hp at the same altitudes the -39 engines did and more than book power lower down.
Also note that may of these planes had two critical altitudes, one at high speed level flight (max ram) and one for climbing (140-150mph/min RAM) and they were thousands of feet apart.
 
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With red stars on wings? It is the I-110, an experimental Soviet fighter by Dmitri Tomashevich, 1942. It was equipped with the M-107 engine and well-suited for mass production, however the performance was rather mediocre. Nevertheless, it was used to improve the M-107 - that is its main merit.
 
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AIUI

P-40D - 23 built for USAAF with 4x0.5" wing guns. Built July 1941
Kittyhawk I - 560 ordered for the RAF in May 1940. Direct purchase by Britain. First 20 with 4x0.5" & last 540 with 6x0.5". So otherwise indistinguishable from the P-40E. Built Aug - Dec 1941. 72 of these went to the RCAF in Canada


P40E - 820 aircraft for the USAAF with 6x0.5". Built Aug 1941 - May 1942
P-40E-1 / Kittyhawk IA - 1500 ordered by the USAAF intended for supply to Britain under Lend Lease (first Lend Lease P-40 version for Britain). These were almost identical to the P-40E but had provision for 3 small bombs under each wing. Built Dec 1941 - May 1942. 153 of these were diverted to Australia, 12 to Canada, 44 to New Zealand.

Detail & Scale 62 P-40 Warrhawk Vol 2
Air Arsenal North America
 

This is all pretty close to my numbers, I think. The discrepancies would be down to different weights (as you can see in your numbers above, you can go from 7787 lbs for P-40D to 8300 lbs for a P-40K, and that is basically the same aircraft) and the extras like antenna masts, antenna wires, sway braces, and bomb racks. Sway braces (for P-40C and later) show up in a lot of the tests and can account for as much as 10-15 mph. Naturally, in the field they often did have the sway braces on. So both my numbers and yours can be adjusted downward by about that much.

(By the way I linked two wartime documents for my numbers on the P-40F speed, the higher speed was directly from a formal test)

Many of the tests were also done at lower power settings and with all the extra gear on, notably most of the Boscombe Down tests in the UK. The Curtiss test tended to be more optimized for better results (lower weight, cleaner plane etc.), while most of the US and Australian military tests often had all the gear but used higher power settings than the British.

As you can see in your numbers, real max speed for the P-40 was around 350 -375 mph at least, but the Wiki now says top speed was 334 mph, which is based on one of the Boscombe Down tests. This stuff filters out into video games and youtube videos etc.

P-40E, in spite of the low critical altitude, were used effectively at around 27,000 feet by the 49th FG in Darwin, by adjusting their tactics. At that altitude they were barely flying but they could get up there, and convert the altitude to speed very quickly in a dive.
 
I don't know if the peculiarity of Allison engines was already mentioned here (I'm just too lazy to look for it). Soviet aviation technicians noted that the engine sound changes little when the supercharging increases above the allowed limits - unlike other engines. Thus. the pilots did not hesitate to use it in flight. It is clear that the engine lifetime was reduced several times, and the maximum speed of many Kittyhawks after this ruthless exploitation was below 400 km/h.
 
The Curtiss test tended to be more optimized for better results (lower weight, cleaner plane etc.), while most of the US and Australian military tests often had all the gear but used higher power settings than the British.
I was trying to keep the individual lines short, and I got "lucky" in that the weight breakdowns kept saying 720lbs for fuel until the near end, Which is one reason that some of the service tests change. For some reason the US and Curtiss agreed that 120US gal was "standard" despite what the tanks actually held. The 52 gal drop tank was an attempt to make up for the reduction from 181 gallons in the P-40 to under 150 gallons in the P-40B.
Curtiss themselves say for the P-40D
15,000ft at military power, 359mph without tank and 330mph with tank
15,000ft at 1000hp(normal) power, 345mph without tank and 324mph with tank. which doesn't track well to be but.........
15,000ft at 600hp (60% normal), 285mph without tank and 266mph with tank.

The D was supposed to have 175lbs of armor and glass together, some times the weights are separate.

Most of the specifications list take-off speeds and most give take-off and landing distances, sometimes for both runway and over 50ft obstacle. The P-40 was not a Spitfire or Hurricane here although much better than a lot of other American fighters.
Speed obviously didn't change much but climb took a real hit due to the increase in weight.

Some of the British/Commonwealth climb tests are going to be quite different than the US climb tests depending on test procedures. Standard British procedure was to use the "normal" rating (2600rpm/1000hp) for the entire time so climb really suffered in the first 5 minutes compared to American testing.
They test their own planes the same so all the British pilots had some understanding of what was going on.
 

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