A reaction engine that carries all fuel and components for combustion and so not requiring intake of any outside substance and hence capable of operation in outer space.
A projected rocket engine in which the energy for the jetstream is to be generated by atomic fission or fusion.
Chemical Rocket Engine
Contain or carry along it′s own fuel and oxidizer, usually in either liquid or solid form.
A rocket engine that maintains the velocity of a rocket vehicle once it has achieved its programmed velocity by use of booster or other engine.