Forgotten Worlds by Capcom, originally released in the arcades in 1988. Several home ports followed,most memorably the Sega Genesis edition in late 1989.
Capcom were always at the top of their game, since they've had a recognizable name. You've got to give the company credit for one thing, they always go all-out and try something that is always unmistakeably theirs. While their rivals at Irem and Konami were pumping out shooters such as R-Type and Gradius (respectively), which featured the usual "one lone spaceship against an enemy armada," Capcom almost always completely skirted that game design philosophy slightly and insisted that "all of our shoot'em-up games will not have spaceships as the protagonist, but rather flying guys."
FW had a few things pretty unique going for it; you'd not collect powerups in the field, rather collect "Zenny" (cashola) to purchase items like Napalm and such from pretty girls in shops (who looked like they should be selling Boba Drinks to our heroes!) What the hell, man, I am trying to save your PLANET, why do you have to look at this as a money-making opportunity! Can't you just give me the bloody Assault Rifle so I can defeat the God of War before he vaporizes the whole neighborhood? GEEZ.
The other, more notable gimmick here was the control mechanism. In the arcade, you had your stock joystick to control player movement, but also a radial dial (a la Arkanoid) to control your shooting direction. This was a new idea for shooters, and it made for some interesting play (and it looked cool, if kind of funny, to watch your guy spinning in place on the screen). Unfortunately, the complex control setup didn't translate so well to the home consoles and so they kind of cheaped out on it (on the Genesis, A and C trigger buttons would spin you clock- or counterclock-wise, and the middle B trigger would shoot). It was still fun, but a little ore awkward to play this way.
Forgotten Worlds is a Forgotten classic, a weird and funky adventure with some nice touches from an exciting time in gaming - check it out! The reissue on Capcom Classics Collection on Xbox and PS2 maps the movement to analog sticks, providing the best control possible for this game. Might have to pick that one up, myself.