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You are, of course, joking.
I have seen some old books published during the war that claim the P-40 could do over 400mph in level flight (and not the Q).
AIr speed indicators were notoriously unreliable at higher than normal speeds. Many planes 'recorded' some astonishingly high dive speeds in WW IIAnd I've seen plenty claiming that the P-40 was "unmaneuverable and slow but rugged" so what?
Nope, not joking. I have no reason to assume that video is made up. They routinely dove to over 500 mph TAS including in training - the English noted this early on with the Tomahawk. I doubt many combat pilots pushed the limits as far as the two tests mentioned in the video (as it would be extremely risky) but they could if they had to. The risk would be to pass the sound barrier in a dive, same as with a P-51 or P-47 etc.
Just because you don't understand it doesn't negate it.
There are also 12 lost to unknown causes here
Another source posted by Eagledad in another thread gave 481 USAAF P-40 claims in the MTO.
How do we know? because war time propaganda newsreels tell us so
You have a history in our discussions in this forum of doubting any historical evidence which doesn't fit your own models of how things work. You do seem quite knowledgable on things like engines and superchargers, but am I supposed to trust your expertise on everything to do with the Air War over all other evidence ?
If you think this is so ludicrous, post some data that contradicts it.
All pilots who flew the P-40 noted it's high dive speed and in fact, diving out of combat (usually a vertical dive sometimes following Split S) became the standard escape maneuver both against Japanese and German fighters. I have never seen any mention of compressibility issues with the P-40 of the type encountered by the P-38. Have you? The only limit or issue described by pilots was either the need to use heavy rudder pressure to counteract the torque at high speeds, and / or the need to adjust trim settings quickly during dive and subsequent pull out.
I spoke to a pilot at an air show two months ago who told me he was making 400 mph in shallow dives during fly bys at the airshow, at 25" Hg and 2500 rpm no less (basically cruise settings) and he told me the fastest he'd flown that P-40N was 500 mph in a dive. And that is a 75 year old Warbird.
Schweik,
To concur with SR6 I have also read many times about the airspeed indicators inaccuracies. I have also read where the Spit had the highest MachCrit of the WW2 fighters. It is very likely that Curtiss did not account for airspeed installation errors or inaccuracies for that newsreel clip.
The airspeed indicator probably indicated what they advertised, but that doesn't mean it was accurate.
Cheers,
Biff
also it should be noted that Martindale made a normal wheels down landing after all that drama, not bad for the fragile spitfire !AIr speed indicators were notoriously unreliable at higher than normal speeds. Many planes 'recorded' some astonishingly high dive speeds in WW II
Just for laughs figure it out. 661 mph at 5,000ft (got to leave room to pull out ) is Mach .884 at 10,000ft it is mach .899
From wike so......
on the Spitfire. ......
Beginning in late 1943, high-speed diving trials were undertaken at Farnborough to investigate the handling characteristics of aircraft travelling at speeds near the sound barrier (i.e., the onset of compressibility effects). Because it had the highest limiting Mach number of any aircraft at that time, a Spitfire XI was chosen to take part in these trials. Due to the high altitudes necessary for these dives, a fully feathering Rotol propeller was fitted to prevent overspeeding. During these trials, EN409, flown by Squadron Leader J. R. Tobin, reached 606 mph (975 km/h) (Mach 0.891) in a 45° dive.
In April 1944, the same aircraft suffered engine failure in another dive while being flown by Squadron Leader Anthony F. Martindale, Royal Air Force Volunteer Reserve, when the propeller and reduction gear broke off. The dive put the aircraft to Mach 0.92, the fastest ever recorded in a piston-engined aircraft, but when the propeller came off, the Spitfire, now tail-heavy, zoom-climbed back to altitude. Martindale blacked out under the 11 g loading, but when he resumed consciousness, he found the aircraft at about 40,000 feet with its (originally straight) wings now slightly swept back.[125] Martindale successfully glided the Spitfire 20 mi (32 km) back to the airfield and landed safely.[126] Martindale was awarded the Air Force Cross for his exploits.[127]
RAE Bedford (RAE) modified a Spitfire for high-speed testing of the stabilator (then known as the "flying tail") of the Miles M.52 supersonic research aircraft. RAE test pilot Eric Brown stated that he tested this successfully during October and November 1944, attaining Mach 0.86 in a dive.
Then look at all the troubles the P-38 and even the P-47 had with mach tuck.
or from Bill Marshall:
The fastest I Have ever heard of a 51 dive was an RAF test in which a MK IV was at .82-.85 M (instrumentation a little fuzzy) and the aircraft had so many wringled panels and fastners fail that the a/c was written off. That was Far above the Placard speed.
But hey, the P-40 was such an under appreciated wonder plane that it could out dive most early jets.
How do we know? because war time propaganda newsreels tell us so
Typhoons never got shoot up japanese twin bombers or other rather vulnerable targets in the CBI or South Pacific.
Typhoons also never got shoot up Macchi 200s, SM 79s Italian transports or JU 52s or Me 323s.
Germans for much of 1942 and 1943 didn't have to come and "play" with fighter sweeps over NW Europe unless they thought they had an actual advantage.
I really don't think the British got value for money from the TYphoon, mainly because of the Sabre engine. It's destructiveness as rocket firing airplane is vastly overblown. the 132 tank kills sometimes claimed was more like 6. The British (and the Allies) could probably have conducted the war with the Typhoon never having been built and would not have affected the outcome in any significant way. (assuming they built 3000 of a different plane)
But simplistic comparisons like number of planes shot down vs number of planes built really don't tell us much.
The P-40 Did affect the conduct of the war by being available in numbers when and where needed in 1941-42-43. However it's continued combat survivability had as much to do with it's opponents stumbling and dropping the ball/s than any great properties of the P-40 it self.
I agree 100% that 1930's - 1940's airspeed indicators were routinely way off, (I would assume modern ones are potentially better but you tell me) but presumably Curtiss engineers supervising the test were aware of it. Now it is also quite possible that 660 mph was one measure (IAS) and the TAS was known to be different, but they published the former instead for propaganda purposes, though I thought that IAS was usually lower than TAS depending on altitude and very generally speaking (though again, you tell me)
The only way to be sure would be to find the document of the test but googling failed for me, all I could determine was that the guy was a real test pilot and that they did do some kind of test at Wright field with a P-40D, which followed another previous test with a slightly lower speed result.
My point though was that the P-40 really didn't have any limits to dive speed apparently accept the dangers of approaching mach. I've yet to see any evidence to contradict that.
If anyone knows the real mach crit for any version of the P-40 please post it. The manual indicates a dive speed limit of 480 mph but that is obviously over-conservative as with so many other things in the manual.
S
You have a history in our discussions in this forum of doubting any historical evidence which doesn't fit your own models of how things work. You do seem quite knowledgable on things like engines and superchargers, but am I supposed to trust your expertise on everything to do with the Air War over all other evidence ?
If you think this is so ludicrous, post some data that contradicts it.
All pilots who flew the P-40 noted it's high dive speed and in fact, diving out of combat (usually a vertical dive sometimes following Split S) became the standard escape maneuver both against Japanese and German fighters. I have never seen any mention of compressibility issues with the P-40 of the type encountered by the P-38. Have you? The only limit or issue described by pilots was either the need to use heavy rudder pressure to counteract the torque at high speeds, and / or the need to adjust trim settings quickly during dive and subsequent pull out.
I spoke to a pilot at an air show two months ago who told me he was making 400 mph in shallow dives during fly bys at the airshow, at 25" Hg and 2500 rpm no less (basically cruise settings) and he told me the fastest he'd flown that P-40N was 500 mph in a dive. And that is a 75 year old Warbird.
We are on other sides of the spectrum, you doubt anything that contradicts your own view of how things worked, even if your view contradicts physics.
Or you stretch and impose your view on an interview or quote that doesn't say exactly what you think it says.
Yes but on the other hand, in Shores MAW you can see that probably a third to half of the combat losses were due to flak (more to flak in 1944 as we previously discussed), and probably half of the "other" losses were on days when the Germans did not make any air to air claims. Engine trouble was mentioned frequently.
Did you read the small print above the tables?
The 592 number is the correct number. We may not know how many they actually shot down,* but we do know how many they claimed. My sources for 592 victory claims for USAAF P-40 units in the Med is from American Victory Roll page 111 and P-40 Warhawk Aces of the MTO (Osprey), page 87, which helpfully breaks down the victories by squadron. You can read it yourself here
S
*MAW gets us a little closer and can explain it for certain days but for some other days it's really impossible to tell who got what kill.
The 400 mph hurricane was simply to show that newspaper headlines or movie newsreels are rather unreliable data sources. When such "data points" conflict with later research or information which should we trust?I should add, Shortround, that your understanding of the physics and engineering is useful, and has been helpful to me and I'm certain many others in these discussions. Your posts have given me valuable insights for example about how superchargers work. I just think you have to be careful with the assumption that provisional physics models, even good ones, trump other sources. You have to remain open to data. Even if you think it may be 'noise' (and some of it obviously is like your 400 mph Hurricane I) you need to keep track of it because there can come a point where the 'noise' starts to outweigh what we thought was the 'good' data and then it's time to re-evaluate your model.
The 481 number is from Ray Wagner's American Combat Planes . Interestingly, if you add up the figures for sorties, victories and losses for fighters in the ETO/ MTO as presented in the USAAF Statistical Digest, they match Wagners' very well.
We can agree on not knowing how many they actually shot down; I, however, don't see why 592 mentioned in some books should be more likely than the 481 mentioned in another.
The 661mph dive of the P-40 is just noise.
The airspeed limit on the P-40D/E was 485mph indicated on page 22 of the April 1941 manual (revised Sept 5th 1941). In the 1943 manual is says 480mph indicated (page 61) and says that 5-8,000ft are needed to pull out of a high speed dive. Also on page 61 is a warning that vertical dives starting above 20,000ft are not recommended because of the danger of compressibility.
It doesn't say what the dangers are or what to do about them and it doesn't say that such dives are prohibited, "not recommended" is pretty weak language.
I am not going to worry about a 5mph difference in the manuals. Pick what you want. Trying to read a gauge to 5 mph out 480mph in a high speed dive (ground coming up at 700 feet per second) with the plane trying to roll to the right is a finer distinction that I would ever try to make.
I recall reading somewhere that the 480/485 mph speed limit was that recommended by Curtiss and that the P-40 could be flown up to another 30 mph faster in a dive. I assume this resulted in damage. I guess this is like the recommended max boost settings to the V-1710-39/63, which could be exceeded but might cause damage. I guess if you want to survive you exceed the limits set on dive and engine power.Maybe 661 is noise but I don't believe the limit was the one from the manual, either one, because pilot after pilot reported diving at over 500 mph... including one I spoke to personally.
I would say that the 485 limit in the manual probably leaves a margin of error. How great that margin is on any given day may vary with the temperature/air pressure that day, the exact rigging/alignment of the aircraft and perhaps the pilots flying technique.Maybe 661 is noise but I don't believe the limit was the one from the manual, either one, because pilot after pilot reported diving at over 500 mph... including one I spoke to personally.