I'm looking for a game for the n64 that was a jet game. It wasn't a sim. I remember playing it as a kid and the only thing I remember was flying and shooting at a massive submarine in a snow environment. It had more of a twitchy fast paced type of game play. Another level I remember is fighting these crawler mech type things in at a flooded city. Again flying.

Try "Aerofighter's Assualt" think that might be it