It may be listed earlier in this thread, I haven't read the whole thing, but have you seen the mock combat between a P40E and Spitfire V with the tropical air filter? This is copied and pasted. Again, if someone told me this I would have not believed it until I read this account.
The tests were conducted over 3rd to 5th of November 1942, at the No.2 Operational Training Unit in Mildura - a very hot dry open locale in western Victoria. Oversighting the tests was Wing Cmdr. Peter Jeffrey; the actual test pilots beng:
Flying the P-40E - Flt. Lt. Arthur and Flt.Lt. Jackson.
Flying the Spitfire Mk.Vc - Flt. Lt. Foster and Flt Lt. Wawn.
All pilots involved were experienced combat pilots, with Arthur, Jeffrey, Foster and Jackson all being aces - Foster (9) flying Spitfires over Europe, Arthur (8) and Jeffrey's (6) flying P-40's in the Western Desert and Jackson (5) flying the P-40 against the Japanese over Port Moresby, New Guinea.
The results of the tests were as follows:
1. The Spitfire was fitted with a Volkes Filter
2. As the Spitfire was fitted with VHF, and the P-40 with HF, no R/T between them could be used.
3. The Spitfire tested suffered from negitive 'G' cutout, a typical Spitfire trait.
4. The Tests were carried out at heights between ground level and 20,000ft.
5. Results:
a) Spitfire had the greater rate of climb at all heights - the difference becoming greater as height increased above 13,000ft.
b) Spitfire is far more manoeuvrable at all heights.
c) Kittyhawk is faster in level speed from 0 to 16,000ft. Above 16,000ft Spitfire is faster and again the difference becomes greater as height increases. Estimated speed advantage of Kittyhawk up to 16,000ft: 0ft - 15mph; 12,000ft - 20 to 25mph; 16,000ft - 5 to 10mph.
d) Kittyhawk accelerates, both in dive and on increase of throttle on the level, far more quickly than the Spitfire.
6) Combat 1 - commenced at 13,000ft (equal height) and lasted for 5 to 7 minutes, in which time the fight was practically a stalemate. At the end of this period height was reduced to 4,000ft when the Kittyhawk pilots decided he had nothing to gain by staying and so broke off by diving away. Thus, in combat up to 16,000ft, the Kittyhawk has the distinct advantage in that the pilot can commence the fight and discontinue it at will. In such a combat the Kittyhawks tactics are to hit and run, and then come again.
7) Combat 2 - commenced at 20,000ft (equal height) and lasted less than 2 minutes. Spitfire quickly gained dominate position on the tail of the Kittyhawk and couldn't be shaken. Kittyhawk pilot broke off by diving away.
8) Combat 3 - Commenced at 16,000ft (height advantage to Kittyhawk) an lasted 14 minutes. Kittyhawk made repeated dive and zoom attacks with the Spitfire alternatively breaking hard to avoid and climbing for advantage where possible. Fight reduced to 9,000ft with neither pilot gaining a decisive advantage.
9) Combat 4 - Commence at 16,000ft (height advantage to Spitfire) and lasted 11 minutes. Spitfire pounced on Kittyhawk and attempted to gain a position on tail. Kittyhawk used speed advantage in first level flight and then shallow dive to gain separation and then climb for advantage. Spitfire countered by climbing hard. Gaining advantage Spitfire used climb and dive tactics to force the Kittyhawk to make repeated diving breaks to avoid. At 7,000ft Kittyhawk used superior roll rate to scissor behind the Spitfire, who countered with steep climb. Kittyhawk then used speed advantage to again gain separation and fight was broken off.
10) Visions - the vision in the Spitfire with the hood closed is better than the Kittyhawk, but it is a definte disadvantage that the hood cannot be opened at speeds above 160mph particulary when searching up-sun.
11) The flying characteristics of the Spitfire make it more suitable for Operations:
a) it is easier to fly.
b) Take-off run is much shorter and so could be operated from smaller landing grounds. Note - ithe Spitfire does not handle hard dirt strips as well as the Kittyhawk.
c) Mixture and boost are automatically controlled.
d) It is not necessary, as it is in the Kittyhawk, to alter rudder and elevator trims over great speed changes.
All these facts greatly reduce the pilot's problems and so increase his fighting efficiency.
The report concluded by recommending that as the large Volkes air filter on the Spitfire cost 20-30mph in top speed, it should be removed inoperational service - or at least an alternative found. Also mentioned was the effect of the Spitfires rough paint finish on performance but the general feeling of the report was that the Spitfire was perahps the better fighter, especially at altitude.
The report also mentioned being surprised at just how well the Kittyhawk managed to hold it's own against the Spitfire in combat, concluding that in combat against an opponet it highlights the importance of using one's aircraft strengths to advantage.