It's kinda slow. Pace could use some adjustment.
I honestly find this game to be quite boring. You're hitting targets, and the only opposition you have is a limitted supply of ammo. So it doesn't have this urgency, this fast pace to it. Here's what I would have done differently.
Give the illusion of a much bigger playing field. I don't feel this sense of accomplishment if I'm hitting a target 10 feet in front of me. In fact, it makes me feel retarded when I miss that target. I don't like it when games make me feel retarded, lol.
If the original character was drawn a heck of a lot smaller, and the missiles were also scaled accordingly, I would actually feel like a crafty baller if I could nail a target at what looks like 500 feet away. And why a painted training target? I want to kill JEEPS! I wanna blow away some BUILDINGS! Let's give some lovin' to some TIGHTLY PACKED GROUPS OF HIPPIE DIRTBAGS!
I would also kill to see that missile give some more boom. Really kick some dirt around. I'll let you in on some secret information in my Flash business. We're working on a game that in a couple weeks will be uploaded to NG, and it has what we have lovingly called "eat shit physics". We measure the impact of an explosion, and how much of an "ooooooooh!" reaction it can create. You're shooting down planes, and what's really driving the gameplay is that the planes don't just pop like a cherry bomb. They roll, they break apart, they burst into flame, they explode into many little flaming bits. So if this game had a much stronger punch, I would get a much greater degree of satisfaction while playing it.
Oh, umm, the preloader doesn't work. I see that you left room for one, maybe you just have to adjust the scripting on it. Or my computer's (more likely) gone bonkers.
Overall, it has some drive to it. Graphics definitely needs a bit more polish. The gameplay needs to be sped up (maybe include a timer?), and the game doesn't have a lot of "kick ass" mechanics tied to it. So it's definitely a "preserve", but it should become a living project where you continue adding features to it. Because it's definitely not as complete as it could be.