In the older discussion
http://bbs.hitechcreations.com/smf/Smileys/default/Forum9/HTML/000713.html we had the problem that noone knows the Cd0 of a real F4u.
Maybe this can help us: The Naca tested a 1/2.75 scale model with several flaps/elevator settings. The report is
http://naca.larc.nasa.gov/reports/1942/naca-wr-l-440 The result is basically this: The F4U only can have a Cd0 of ~0.018-0.019 (This is the value for 355mph@sealevel) when the aillerons, rudder and elevator are perfectly centered (0° position), power off (no prop drag?), the horizontal stabilizer is in the lowest possible AoA position to the power line (~1.5°) and the best elevator nose shape.
IMO this is not a configuration where at full power a real F4U will fly straight on...
Look at Cd0 values for more realisic AoA of the horizontal stabilizer, add a bit drag due to elevator, ailleron and rudder deflection, add propeller drag, and youŽre quickly in the range of 0.021-0.022. Has a model a better "production" and surface quality than a serial-production F4U-type? IŽd say yes.
The only question that remains for me is whether the navy calculated the performance only for the F4U with an irreal low Cd0 or whether this was a usual practise for other fighters too...
niklas
[This message has been edited by niklas (edited 08-21-2000).]