Vern's Rocketry Web Site. Rocket engine nozzle. Figure 1: A de Laval nozzle, showing approximate flow velocity increasing from green to red in the direction of flow Nozzle on the first stage of an RSA-3 rocket A rocket engine nozzle is a propelling nozzle (usually of the de Laval type) used in a rocket engine to expand and accelerate the combustion gases produced by burning propellants so that the exhaust gases exit the nozzle at hypersonic velocities.
History[edit] Atmospheric use[edit] Richard Nakka's Experimental Rocketry Site. Lecture Notes.