0745 on a Monday morning at 3FTS Leeming around 1970 was time to test the crash alarm. It was also time for the weather ship to get airborne.
34 threshold at Leeming was not visible from the tower.
Crash alarm test coincided with the engine of the weather ship JP deciding to disassemble itself spraying rapidly-rotating compressor blades, some of which narrowly missed the caravan and reportedly made a very worrying noise as they sped past..
Tower pressed crash alarm for real after call from QFI. Rest of station assumed finger trouble on test button, which didn't help.
QFI leaped out and broke 100m sprint record. Student was brought short after a few feet by attached dinghy lanyard.
No-one physically hurt, but I never did find out what the caravan occupant thought of it all.