Not a full review yet, because I've only played a few missions. For those that don't know, the original Pilotwings was a very early SNES game famous for showing off Mode 7, a program that gave the illusion of moving through a 3-D environment (but isn't "true" 3-D just an illusion, too? It's on a flat screen, after all...but I digress). I briefly played that at a friend's, and though I was terrible, it was pretty fun.
The game got one sequel, and that sequel launched alongside Super Mario 64. As one of two very first 64 games, the graphics are...not easy on the eyes. The character models are basically hideous. Still, to the game and system's credit, the environments look pretty darn good. There's only slight fog, the islands are detailed with flaming smokestacks, castles, icy mountains and varying weather conditions, depending on your location. There's also a neat "heat wave" effect where thermals are present, and recognizing it is integral because they get you loft with the hang glider.
As for the game itself, like its predecessor, it's a flight-training sim. As such, it's pretty short in adrenaline-pumping action sequences (though your gyrocopter is equipped with missiles which you get to use). What you do get is a surprisingly realistic flight sim whose gameplay holds up very strongly more than 11 years later. It effectively uses "selective realism": simulating reality enough to get an amazing sensation, but not to the point where it becomes overly complicated or tedious.
You get a variety of vehicles to train with. You're pretty much limited to steering and swooping with the hang-glider, and seeking out thermals to increase height is essential. The gyrocopter is basically a helicopter (I don't know the difference), so you get free flight in any direction and you get the aforementioned missile payload. The jetpack allows for a thrilling break from reality.
The missions typically involve flying through rings or hitting/shooting a target then making a smooth/accurate landing. Their difficulty curve is reasonable, but what's most fun is deviating from the missions and simply doing stunts across the well-designed levels.
Skydiving is an unlockable option, and there are a couple other vehicles, but the only one I've unlocked is Birdman. Birdman essentially straps wings to your character and lets you fly anywhere in the level, showing the developers realize how much fun simply free-flying is.
Pilotwings isn't an action-packed dogfighter, but it captures the essence of flight expertly, and is a great relaxing game to play before bed or simply want a gentle thrill.