P-40's dive speed?

[Nathan]

How did the P-40's dive speed compare with other WWII fighters? I know it had one of the fastest dive speeds. But I think that was compared to enemy aircraft. Alos curious how it was compared to allied aircraft.

Thanks,
Nathan

[marine air]

It sucked! In Col. Bob Scott's book "God is My Co-Pilot" he said it had a very responsive roll rate, nice climb and good speed for it's day but it couldn't outdive anything. That big pre-Naca intake scoop acts like a small dive brake. I have an early 1943 original printing of his book, so he was obviously comparing it to fighter designs pre-1943.

[davem]

From the pilots handbook for the E model, maximum dive speed was 460mph.

Not many know, but there actually was a maximum dive angle that was painted on the canopy in red - it can be seen in this photo (above the 'P' in property)...quite the angle!!

http://www.rcafkittyhawk.com/_wizardimages/143.gif

[Bill Greenwood]

I suspect that 460 mph may be the max INDICATED dive speed of a P-40, if not that would be pretty slow in true airspeed. For comparison the max book dive speed of a MKIX Spit is listed at .85 mach or about 550 mph TRUE airspeed, and they test dove a Mk XI to over .9 mach, about 610 mph. Some fighters like a P-51, Jug, Fw 190 may initially gain on a Spit in a dive, but given enough room the Spit can catch them.
An experience P-40 civilian pilot, Fred Sebby said it dives like a polished manhole cover.

[sdennison]

From the pilots handbook for the E model, maximum dive speed was 460mph.

Not many know, but there actually was a maximum dive angle that was painted on the canopy in red - it can be seen in this photo (above the 'P' in property)...quite the angle!!

http://www.rcafkittyhawk.com/_wizardimages/143.gif

Dave, How in the he11 did they expect a pilot to stick his head out of the cockpit to look at that line at 460mph?

Was the true dive speed different from what the ASI could read? I don't know the technicalities of that system. Could an aircraft actually dive faster that the instruments could read?

[davem]

LOL

The canopy was open for the photo, very easy for the pilot to see with the canopy closed.

I recall the P51 had some fluttering problems in a dive, so it was limited in dive capabilities - I might be remembering something wrong though.

D

[Nathan]

It sucked! In Col. Bob Scott's book "God is My Co-Pilot" he said it had a very responsive roll rate, nice climb and good speed for it's day but it couldn't outdive anything. That big pre-Naca intake scoop acts like a small dive brake. I have an early 1943 original printing of his book, so he was obviously comparing it to fighter designs pre-1943.

That can't be true. I have heard nothing but good things about the P-40's dive speed. 500+ mph in fact. And it could acheive that in a relatively short time. I have read many accounts of where the pilots pushed the P-40 over in a dive and maxed out the speed inicator in no time. Im sorry marine im not trying to be mean so please dont take this post the wrong way. I am open to all options but I never heard where the P-40 wasn't good in a dive.

Last edited by Nathan on Wed Mar 19, 2008 9:16 pm, edited 1 time in total.

[Bill Greenwood]

Sdenison. Indicated airspeed is what the airspeed indicator (speedometer) reads. But for it to be TRUE airspeed, that figure must be corrected for non standard air molecules. At high altitudes and hot temps the air is thiner, so it doesn't impact the ASI instrument as much. Lets say I am at slow cruise at 11,500 feet on an summer day. The indicated airspeed would be about 175 knots,, but the true (corrected to standard air specs) would be about 214knots or 245 mph. Standard air at sea level is 59 *F and a barometer of 29.92, At say 35,000 feet an indicted speed of 375 might be 500 true. These are AIRspeeds. To get ground speed you must add or subtract head or tailwinds.

[sdennison]

LOL

The canopy was open for the photo, very easy for the pilot to see with the canopy closed.

I recall the P51 had some fluttering problems in a dive, so it was limited in dive capabilities - I might be remembering something wrong though.

D

Whew! The line was painted on the glass, not the fuse.

Reminds me of the two guys who rented a fishing boat. Every time they caught a fish, one guy would put an X on the side of the boat. His buddy asked "Why?" He told him that next time they would know where to go to catch the fish again. His partner commented, "Dumba$$, how do you know we will get the same boat?"

[mas]

It sucked! In Col. Bob Scott's book "God is My Co-Pilot" he said it had a very responsive roll rate, nice climb and good speed for it's day but it couldn't outdive anything. That big pre-Naca intake scoop acts like a small dive brake. I have an early 1943 original printing of his book, so he was obviously comparing it to fighter designs pre-1943.

???? On page 139 of MY first edition (1943) "God is My Co-Pilot", Scott relates some of the advice given to him by George Paxton of the AVG: "The P-40 is the strongest ship in the world. It's heavy as hell, but that makes it out-dive just about anything, and it'll out-dive the Japanese two to one."

Most pilot reports I've ever read about the P-40 list it's diving ability as one of its assets. The design max dive speed was indeed 460 mph indicated airspeed, but the old Hawk was built like a tank and that speed was exceeded by a large margin by many a pilot in combat. I believe when most pilot's spoke of its diving ability they were referring more to its initial rate of acceleration in the dive than its all out speed.

[davem]

From Mark Hanna's article on flying the P-40 in Warbirds Worldwide #3:

"Where the P-40 excells and will throw out most other fighters is in diving, rolling maneouvres".

Mark Hanna had extensive exposure to a great variety of aircraft.

I don't fly our aircraft, so can't really say much. However, I never have heard negative stories about diving the P-40.

[Bill Greenwood]

The two lacks I have read of the P-40 in combat is lack of climb, especially above 15,000 where the Allison doesn't breath as well, and a modest top speed in level flight. I have read Tex Hill's combat accounts and they always tried to dive on and away from Japanese opponents.
I have never had a simulated dogfight with one, but just flying in airshows beside them they do seem a little slower. Wonder what speeds they have turned at Reno? Neat looking planes though.

[HJ]

In the Breitling Fighter days of OFMC Ray Hanna was always singing the praises of his P-40E and its dive speed capabilities,certainly at low-level it was Ray's favourite.