Top Gun...
In all seriousness though, for what I class as an out-and-out action movie, I'd have to go with The Rock. Its just action-pron. But then, maybe its my age but I do love those mindless, OTT, fire-and-forget 90's action movie's;
Face/Off
Broken Arrow
Die Hard(s), natch
Executive Decision
Passenger 57
Bad Boys(!)
Under Seige
Eraser
Patriot Games and so forth.
I class the likes of Heat in an entirely different category of regard - nominally on the basis of tangible or existant acting. Heat is probably one of the best movies ever, and the final scene with that music playing; "I told you I wasnt ever going back"... phenominal.
Edit to add I actually put Ronin and Leon in the latter category aswell, two films almost as good as Heat. There are characters in there, not just explosions and one-liners.