Ive flown over Cuba a bunch of times on my way down to MBJ or Costa Rica. Honesty their controllers have the best English south of the border, and are very nice to work with.

something else you can show

http://en.wikipedia.org/wiki/Jos%C3%...tional_Airport

read terminal 2

Cubana is indeed allowed to fly throught the American Aerospace but with some restrictions. Not that I'm a real pilot, but I have both flown on ACA964 and CUB180, ACA reach Cuba faster than Cubana's flight, I therefore don't see any other eason other than restrictions to fly over certain airspaces.

ACA uses an A319 and Cubana a leased A320 from Grupo TACA