bipropellant system

A bipropellant system is a type of liquid-propellant rocket engine that uses two separate propellants: a fuel and an oxidizer. These are stored in different tanks and are mixed and ignited in a combustion chamber. This allows for higher exhaust velocities and better control over the engine's operation, including throttling and restart capabilities, compared to solid-propellant systems.1

Liquid-propellant engines are preferred for many applications, especially upper stages of rockets, due to their efficiency and control. Common oxidizers include liquid oxygen, nitrogen tetroxide, and hydrogen peroxide, while fuels can range from liquid hydrogen and kerosene to hydrazine. The choice of propellants depends on factors like performance requirements, density, safety, and cost. Bipropellant systems are a cornerstone of modern rocketry, enabling complex missions in space exploration and launch vehicles.123