I first encountered the F15 at my first Farnborough Show in 1974. (The YC15, which metamorphosed ito the C17 was there too)The McD test pilot who was flying it visited ATC to discuss his display airspace. 'How much do you need?' said my boss. 'Aw 21 thousand will be OK' said the pilot. 'You can have 9 thousand' said my boss. 'I can make do with 16' said the pilot. 'You can have 9' (my boss). 'I don't think I can stop it climbing by 9' said the pilot.
In the event he only got 9; imagine the surprise one display day of a BEA Trident crew outbound from Heathrow when they had a clear view of an unfamiliar jet fighter perform a loop ahead of them and clearly above their level!
Fast forward to Coningsby 1990. At camp with my cadets, some F15s were on detachment from Bitburg. Their awesome performance was just as good. After rotating, they would continue an almost vertical climb until lost to view, rather reminiscent of a Lighting departure.