In my day......as an SAC you had to have signed on for more than five years to qualify for the 'non-hairy' blues; the longer engagement qualifying for a better quality cloth, known as a T63 if memory serves me correctly. The effect of course, was clear and evident segregation by the SWO when looking for likely candidates for parades! As a "Hairy" airmen I never did one! The posh lot in barathea copped the lot!
