Flash Bulb Rocket
A flash bulb rocket is a hypothetical rocket inspired by the flash bulb of 1960s photography. A pressurized cold oxygen bottle feeds oxygen through a combustion chamber containing aluminum coated aluminum oxide threads. Some oxygen is used to oxidize the aluminum. The excess is heated as it passes by the aluminum oxide remaining in the combustion chamber. The hot oxygen and perhaps some aluminum oxide particles exit the rocket by an expansion nozzle. The flash bulb rocket is ignited just as an ordinary flash bulb with aluminum and perhaps some magnesium filaments in an oxygen atmosphere in the ignition chamber. The heat from this combustion melts a barrier to the main pressurized cold oxygen bottle. The surge of pressurized oxygen into the ignition chamber compresses the excess oxygen still there and heats it further. This melts the connection to the main combustion chamber feeding the hot oxygen into the aluminum coated aluminum oxide threads there. This rocket would have a low specific impulse and a high empty weight but is should be good for a dependable small impulse by a simple rocket that can be made from lunar materials. By guesstimation such a rocket might have an exhaust velocity of 1500 meters per second and an empty weight of about 70%. It would be possible to build and test such a rocket upon Earth.
