The rule about Cranwell Flt Cdts having to wear civilian hats in public was still around in 1968-9. You were required to wear the wretched things if out in civilian clothes in Cranwell village, Lincoln, Grantham or Sleaford. Not to raise to young ladies we knew as we never got much of a chance to meet any - it was in case we recognised one of our officers.
So we used to go to Newark...
When most of us became 'Aerocrat
' APOs after a year at Cranwell and set off for 3-4 years of fun, drunken debauchery and UAS flying, many a civvy hat was given a Viking funeral on the JMPG on the night we came hossifers!
I guess the rule died out when the first Graduate entrants arrived on the scene at RAFC? 'Calling' had gone out only a few years before I joined.
Another old 'personal behaviour' rule we were taught was that a male officer may not form a close relationship with a female officer on the same station! Some old Queen Bees still enforced this as late as 1977! A Wg Cdr and a WRAF Flt Lt who lived-in and were 'going out together'
on a station at which I was serving had to leave the station in different cars at different times to avoid the old biddy's attention and displeasure!
Tell that to 't yoof of today......