Kyleb wrote:Other than the designation, what is the difference between an AU-1 and a F4U-X?
The AU-1 evolved from the F4U-5. It had extra armor protection for ground attack, and an engine optimized for low altitude operation. I guess that's why they gave it the A desingnation instead of F, as it wasn't really that much of a "fighter" anymore, especially in the new age of jets.
Visually, it differed from the -4 and -5 in that it had no scoop(s) on the cowling, and it had five hardpoints under each outer wing instead of four. It was 10 inches longer than the -4, but the same length as the -5.
The ultimate Corsair, the follow-on F4U-7 built exclusively for the French, was basically an AU-1 airframe with the high-altitude engine of the -4.