Earthbound

An eager, space-enthusiast technician (played by Robert Reed of The Brady Bunch) installs a smaller Guidance Control System he designed into the rocket ship. There is now room in the equipment bay for him to stow away on the next flight. But during the 12G takeoff his improvised couch crushes the equipment rack, causing the ship to lose all power before reaching orbit. The uncontrollable ship will quickly re-enter and burn unless repairs can be completed.