In the interest of reducing the download time to discuss the above named topic, I am starting a new thread, hopefully devoid of the previous bickering.
The discussion of P-38 Power-on stall speeds led me to question two gentlemen who are among the leaders in P-38 flight time still alive. Arthur W. Heiden (essentially wrote the last chapter in Cadin's P-38 book) and Stan Richardson served with the 20th and 55th fighter groups, respectively. I wrote each via e-mail, the following:
"Hi guys,
I hope everyone is well. All is fine on this end.
I have a question that one of you may be able to answer.
Francis Dean published a book that presents the Navy sponsored fighter conference of 1944. In the text, Dean describes the P-38
as having a higher power-on stall speed, than power-off. This strikes me as odd, given that a large portion of the wing and flaps are blown by the slipstream. The Grumman US-2B and C-1A, both twins with
1,525 hp engines, and weighing in at roughly 19,000 lbs (for a comparable power to weight ratio with the P-38) have a power-on stall, both clean and in landing configuration, that is 6 knots slower than power-off.
My question is this: Is this a error, or did the P-38 have some odd aerodynamic characteristic that caused it to stall at higher speeds with power-on? I tend to think that it is an error in the book, simply because it defies the conventional wisdom. Could either of you clarify this?"
Art Heiden replied:
"Corey, thats the damn'est thing I ever heard????? Can you contact Left Gardner? Have some questions for him, too. Art"
Stan Richardson replied:
"This is the only reference to stall speeds in any of the P-38 manuals I have in inventory. The P-38 would have stalled at lower speed under power. The Fowler type flaps enlarged the wing area and with power applied there would be more air passing over the lifting surface, hence lower stall speed. In almost 30,000 hours of flight time logged I don't believe I ever flew an aircraft that stalled at a higher TAS when under power than when power was off. I suppose it's possible under very high angles of attack that a discrepancy could creep into the IAS readings to give the impression that the aircraft stalled at a higher speed under power. The underwing placement of the pitot tube on the Lightning may or may not influence the IAS readings at stall under high power conditions vs power off."
[Unable to display image]
Stan tried to send some chart from his original dash one, Pilot Operating Instructions, but the image would not display. I have asked him to re-send it.
Art and Stan have over 63,000 combined hours of flight time, with much of it in fighters, including the P-38F,G,H,J,L and P-322, Castrated Lightning, which was largely assigned to RTU (training)units. Going through my notes, I also found a reference on the stall issue from Tony LeVier. Tony said that, "you had to be careful to avoid
stalling while flying on one engine. This is because the wing with the dead engine stalled long before the wing in the slipstream. This was something that would completely ruin your day if you were on short final."
I believe that the comments of these three pilots confirm BADBOY's well thought-out analysis and conclusion that the P-38 stalled a lower TAS with power on, than off.
It appears that the data to the contrary in Dean's Fighter conference book is a typo, or simply an error.
My regards,
Widewing
