This is all done by memory, corrections are welcome:
The crash happened at the 1993 Royal International Air Tattoo (not sure if it was "Royal" back then). The two MiG's were giving a formation display, similar to the French Mirage F.1's. During a loop the wingman lost sight of the leader and misjudged the rest of the loop and he hit the lead aircraft just behind the cockpit with his left wing.
Both pilots ejected and were not hurt (although there are stories about the lead pilot punching the wingman on the nose when they met on the ground - not sure if it is true
On the ground a few people suffered minor injuries. I think one guy broke his leg when he jumped the wing of a C-130 on of the planes were heading towards.