Subtle enough that it might have been unintentional, given the film, but count how many times Preston gets shot down by Guthrie. Before she finally agrees to go out with him, she's shot him down five times, enough to make her an Ace if they were air-to-air kills.
Also, how does Preston finally convince her to go out with him? Instead of approaching her with his typical cocky presumptuous attitude, he enters the room loudly declaring that Guthrie is the greatest, because she helped him overcome a huge problem he'd been having in training. He's finally thinking about others instead of himself.
Preston's cockiness doesn't seem to be a new development, going off of Guthrie's reactions to him, but at least some of it could be him coping poorly to the trauma of his combat experience, having narrowly avoided death at Eric Stohler's hands after watching his friend and a chopper full of DEA agents get blown out of the air. Ultimately he has to place his trust in others to succeed in his mission, especially with Guthrie's role as a scout for the attack choppers, sneaking ahead and spotting for targets and threats.
Fridge Logic:
Why didn't they just put the monocle on the other side of Preston's helmet?
The helmet might not have been designed with interchangeability in mind, with internal wiring or circuitry not being movable. It was a product of the 80's, after all.
If they were expecting an air to air threat, why not deploy fighter jets, which are actually designed to engage and destroy air to air targets, rather than taking a bunch of attack helo pilots trained in ground attack and reinvent the wheel with them? Of course, if they had done that, there goes the central plot of the film.
Ironically, fighter jets are among the worst choices for engaging a helicopter, and there are several reasons for this...
Helicopters can operate at altitudes that render radar tracking pointlessnote Even aircraft with 'look-down-shoot-down' capability can't see a helicopter twenty feet off the deck., and in certain environments, even IR-Guided Missiles have trouble seeing the bloody things.
Helicopters have a nasty habit of being able to 'hug' obstaclesnote Buildings, cliffs, bridges, etc making for some... Hilarious results should the aircraft in question mess up a gun-run on the Helicopter. And finally...
Helicopters can't stall like a fixed wing aircraft can, and as a result, can pull simple maneuvers to dodge an incoming missile and force overshoots.
In tests, Mi 24 Hinds were actually able to 'kill' F-15s as a result of the listed reasons above. Although prior to the tests in question, an F-15E 'Strike Eagle' killed a Hind by simply dropping a 2,000lb Laser Guided Bomb on it.
In the climactic battle, Little's Apache is shown equipped with Stinger missiles on the wingtips. With their main objective being to engage Stoller's helicopter, presumably the other Apaches have them as well. Yet Preston and the other pilots engage the cartel's air assets with everything but air-to-air missiles. If they had them, why didn't they use them?
Missiles take a moment to actually lock onto a target, and the Stinger isn't an off-bore-sight capable missile, so against Stoler, they didn't have much chances to actually lock onto him. Against the fixed-wing aircraft they should've been used, but I get the feeling that the movies budget, and the military, may have only allowed for a single Stinger Shot, so they saved it for a fairly awesome moment.
