When Goose introduces Iceman to Maverick at the bar, Iceman is shown in shades drinking a tall glass of ice water. At first, one can think, "Ha. Ha. His drink has ice because he's Iceman. And he wears sunglasses to pretend to be cool because he's Iceman." However, it's water, meaning he doesn't drink even off duty, and he's next to bright neon lights. Iceman doesn't want to be visually impaired or hungover during class tomorrow. He's playing it safe, which is part of his Establishing Character Moment.
Why is the final dogfight fought at knife-fight visual range, when the F-14 has Beyond Visual Range missiles? It's because of the characteristics of the BVR missiles the Tomcats carry. The AIM-54 Phoenix is an extremely long-range (100 miles) bomber killer easily outmaneuverable by jinking MiGs. The other long-range missile at that time would have been the AIM-7F Sparrow missile. These missiles are Semi-Active Radar Homing, meaning that they are guided to their target by the aircraft’s radar. Therefore, a pilot needs to maintain a continuous radar lock on a target for a Sparrow missile to successfully hit it. This precludes the Sparrow from being used in a dogfight, as an enemy aircraft needs to remain within the Tomcat’s boresight for a relatively long period of time in order to obtain and maintain radar lock. Since the MiGs are more maneuverable than a Tomcat, radar lock is extremely easy to lose, turning that Sparrow missile into an unguided bottle rocket. We see that the MiGs fly close in bunched together, then split as the range closes. If a Sparrow had been fired at that initial radar signature, radar lock would have been lost when the MiGs split off, rendering the Sparrow useless again. The heat-seeking Sidewinder is fire and forget — and therefore perfect for close-range dogfights.
