Abstract: The invention is an acceleration switch designed to fuse switch unguided ballistic warheads at a specified elevation above land. It houses two spring controlled and inertia responsive electrically conductive pistons, one of which would electrically program the fuse switching acceleration value when advancing, upon sensing peak acceleration (as the reentering warhead experiences its peak deceleration), and the other of which would close the fuse switching circuit when, upon retracting, it senses the programmed fuse switching acceleration value. The switch also incorporates a remotely steppable bi-directional stepping motor which would be employed to regulate the inactive position of the fuse switching piston.