This is basically a mixture of Missile Command and Air-Sea Battle, just at a quicker pace! The Missile Command comparison comes from the fact that when the enemy ships get too low, they can destroy your base (you lose cannons). The Air-Sea Battle element is easy to see. The ships all fly in a straight line at multiple heights, and varying speeds (much faster in this game though).
All in all, as a kid, I played this game a lot. Mostly due to the difficulty in later stages, the sound effects, and the satisfaction of killing those blazingly fast suckers that often end a stage or end one or all of your cannons.