This contains some hints, although not specifically what you're looking for:
https://theasc.com/articles/flying-high-with-top-gun
They mention shooting on Panavision, apparently Panaflex, but with lenses adapted to suit the purpose. For the long shots, they apparently went all the way up to 4800mm for tracking shots, but I suspect that the deck scenes were shot at maybe 1600mm by the looks of it. For the footage filmed within the cockpit, they apparently used Nikon lenses so it's conceivable they also used Nikons for some of the longer shots.
This page mentions Panavision as the lens manufacturer:
https://shotonwhat.com/top-gun-1986 However, IDK if Panavision ever made such long glass to begin with; I doubt it, which means they probably adapted 'something' and added teleconverters when necessary. This page is already a little more specific:
https://www.imdb.com/title/tt0092099/technical/ It suggests they used pretty much whatever they could get their hands on.
You could try and contact Jeffrey Kimball; he's old, but apparently still lives
https://en.wikipedia.org/wiki/Jeffrey_L._Kimball
Long shot I suppose. But wasn't this about long shots to begin with...?