Been lurking for years, here's one of my memorable duty dogs:
Ord Cpl / Dep Gd Cdr RAF Scampton mid to late '80s, approx 22:30 I received a phone call from Lincolnshire Police along the lines of "One of your neighbours north of the airfield has reported an empty car in one of the passing places on the single track road outside the fence. We've checked the registration & it doesn't exist! Thought you ought to know."
PIRA activity aginst mainland military installations was at it's height (Ternhill, Wyton) so I wasn't happy. There are 5 of us (6 if you count the Duty RAFP) to defend the unit. so i called out the Ord Sgt / Gd Cdr, who in his turn called out the SDO. Meanwhile we tried contacting the Duty RAFP who was out on his SSA site checks and of course in the STORNO blackspot.
As everyone was assembling in the guardroom, the Duty RAFP arrived back and said "Hang on that registration is familiar" and scooted of to return with his duty book - in the back of which was a list of civilian registration plates applied to HQP&SS military vehicles and there it was. Panic over - sort of, we were subject to a penetration test. He advised we just carry on as normal & when they completed what they do, they would come & make themselves known.
Sure enough an hour or so later a Sqn Ldr Provost Officer came to the guardroom and then got a strop on when I asked to see his F1250 before letting him into guardroom. This was defused by his Flt Sgt showing me his F1250 & warrant card, but he did query the incresed security as it wasn't normally like this. " Been like this since we've been live armed Flt" said I. Big pause, then business carried on.
Later the SDO showed me the flash signal ordering all physical penetration testing to cease immediately. Seems HQP&SS didn't know all Support Command Stations were now protected by Airman with actual guns 'n' bullets!
Incidentaly, witnessing the Stn Execs first ever weapons handling tests with a SLR made me think that Christmas lunchtime was definitely a time not to be anywhere near the main gate.