As I vaguely recall it in the late 70s (78 I think, when I was going through Cranwell as a student) there was a least one DEP JP 3 course (? 1 DEP aka "The wooden tops") where the guys had nil previous flying. By the time I got back to Sleaford Tech as a QFI in the mid 80s all courses were on the 5, the short course guys were generally from the UASs, the long course students had come via Chippies/Swinderby..