Fort Apocalypse is a 1982 game for the Atari 8-bit family created by Steve Hales and published by Synapse Software. Joe Vierra ported it to the Commodore 64 the same year.
Fort Apocalypse is a 2D multi-directional scroller where the player navigates an underground prison in a helicopter, destroying or avoiding enemies and rescuing the prisoners. A contemporary of Choplifter, it has similarities to that game as well as the arcade games Scramble and Super Cobra.