F8F wing profile

[Trilisser]

Simple question: why did Grumman select the relatively old NACA 230xx series profile for the F8F when nearly every other maker had adopted newer profiles? Plus that the F8F root profile is quite thick for the era (18%).

 

[MikeGazdik]

Just taking a stab at it: I would say because of the smallish wing area, and because it had to land on carriers, Grumman went with a proven design. I would say that all of the WWII "Cat" fighters were all very conservative designs.

 

[Aaron Brooks Wolters]

And if I'm not mistaken, it was a rush design to get a fighter into the Pacific Theater to combat the Kamikaze attacks. It was designed to get off the flight deck and up to altitude extremely quick.

 

[Siegfried]

The NACA 5 digit series were an modification of the NACA 4 digit series achieved by systematic variation of the leading edge to achieve improved coefficients. There was a penalty in terms of a harsher stall knee though it wasn't much of an noticable problem. These profiles, like the laminar series were all designed by Eastman Jacobs.

 

[norab]

And if I'm not mistaken, it was a rush design to get a fighter into the Pacific Theater to combat the Kamikaze attacks. It was designed to get off the flight deck and up to altitude extremely quick.

showing my age now, but back in 1969 when the big EAA fly-in was still at Rockford (hadn't been moved to Oshkosh yet) They staged a race between a Bearcat and a P-51 starting side by side on the runway to see who could get to altitude first. The Bearcat took off, pulled up his gear and flaps, did a 360 and was making a simulated firing run before the Mustang could get it's wheels off the ground. Impressive as hell.

 

[Trilisser]

Conservative approacjh might have had something to do with it, but nevertheless it is quite interesting that an oldish and thickish profile was selected. And if one compares the F8F performance to -4 and -5 Corsairs, one might conclude that not a particularly clean design...

 

[chris mcmillin]

Also interesting that that same airfoil on a modified F8F is the holder of the 3KM FAI world speed record for piston powered, propeller driven airplanes at 528 mph, and has held it since 1989 after taking it away from a P-51.
Chris...

 

[renrich]

The design and development of the F8F began well before the Kamikaze threat began. The F8F was designed to operate from the CVEs with their short flight decks. A short take off run was obviously desirable and the small wing needed to generate lots of lift.

 

[norab]

just for laughs throw this into the mix

As a weight-saving concept the designers came up with detachable wingtips; if the g-force exceeded 7.5 g then the tips would be allowed to snap off, leaving a perfectly flyable aircraft still capable of carrier landing. While this worked very well under carefully controlled conditions in flight and on the ground, in the field, where aircraft were repetitively stressed by landing on carriers and since the wings were slightly less carefully made in the factories, there was a possibility that only one wingtip would break away with the possibility of the aircraft crashing. This was replaced with an explosives system to blow the wings off together, which also worked well, however this ended when a ground technician died due to accidental triggering. In the end the wings were reinforced and the aircraft limited to 7.5 g.