Back in the 70's(?) RIAT was moved to Boscombe Down while they resurfaced the runway at Fairford. During the display, a couple of Tornados took off to intercept a pair of Russian aircraft which had flown non stop from Russia and lead them to Boscombe from the North Sea. Eventually these two Russian aircraft arrived on the approach. I can't remember exactly what they were but one was a smallish twin like a regional jet, the other was a MiG 29 (or similar). The MiG was flying echelon starboard to the airliner who was lined up in the centre line. This put the MiG heading between the runway and the crowd line which was much closer in those days. The commentator started to mutter questions about what this guy was intending to do. He got so low that I lost sight of him behind the crowd until I heard the commentator say something like "Oh, that's interesting". The Mig appeared with lots of noise, going vertical and then went into a typical MiG29 display. Absolutely amazing and it was claimed that it broke the record for the maximum distance flown to perform a display.