Well, I just played it.
It uses the default controls, nothing special.
I use an azerty french keyboard but this is what it should be on a qwerty one:
5 = coin
left-right arrows/CTRL/Alt = select level
left-right arrows = P1 spin left/right
CTRL = P1 fire
Alt = P1 thrust
Space = P1 hyperspace
D-G = P2 spin left/right
A = P2 fire
S = P2 thrust
Q = P2 hyperspace
That's an antique, it is completely silent but it is the very first dogfight game.