Did a fair bit of official and "unofficial" fighter affil over twenty years ago in W. Germany when it was quite routine to find the boys wanting to play. The Alpha jets never got close enough, nor did the Harriers. The Harriers jocks said that IF they were on the way back home with a few rounds to spare they might have a go on an unarmed heli BUT if there was any chance of retaliation with upwards lumps of lead they just wouldn't risk it.
Our biggest risk was probably from small arms. I never liked to fly as number 3 in formation, the AK-47s were cocked and pointing upwards by then - number one flies over at twenty feet "Wassat? Number two flies over "Not ours!" Number three "Gotcha!" The second biggest risk seemed to be our own RAF Regiment Rapier boys. If we didn't fly tactically they claimed kills with pointy rockets despite the fact that we were squawking the correct IFF. The third biggest risk was from the Yanks who seemed to think a Puma was a Hip, even when stood next to it and talking to the crew.... "Say - are you guys playing the ENEMY?"