Abstract: 1. A missile launching system comprising a launching tube including a first hamber and a second chamber containing the missile to be launched, a source of gas compressed to a pressure substantially in excess of the pressure of the environment into which the missile is to be launched, and valve means for admitting said compressed gas into said first chamber a bulkhead between said first and second chambers, said bulkhead being formed with a plurality of openings, a plate formed with similar openings mounted for rotation on said bulkhead, and means for rotating said plate to gradually align the openings of the plate with the openings of the bulkhead during the launching movement of the missile in the launching tube to continually increase the flow of compressed gas from the first chamber to the second chamber causing a rapid rise of pressure in said first chamber and resultant constantly increasing pressures communicated to said second chamber via said adjustable orifice for lauching said missile.