i remember watching a documentary on discovery or NGeo some time ago and they said that according to some recent research ity has been learnt that for the supersonic aircraft of the future women would be better able to control the aircraft at high altitudes and multiple mach speeds and thus prove better pilots. the reason they gave was that due to their smaller size, bone structure and physique they are naturally built in such a way that the distance between the brain and the heart is shorter as compared to men, and so when the pilot blacks out, if the pilot is a woman, she'd black out for shorter time and would be able to resist black out longer than a man. im not sure of the rest of the details and cant recall them. may look out search and post later.