Most liquid engines use a bipropellant, consisting of two liquid propellants (fuel and oxidizer) which are stored and handled separately before being mixed and burned inside the combustion chamber.
Liquid-propellant rockets have a motor that feeds liquid propellant(s) into a combustion chamber.The cylinder is ignited from the inside and burns radially outward, with the resulting expanding gases and aerosols escaping out via the nozzle. Solid-propellant rockets or solid-fuel rockets have a motor that uses solid propellants, typically a mix of powdered fuel and oxidizer held together by a polymer binder and molded into the shape of a hollow cylinder.All launch vehicle propulsion systems employed to date have been chemical rockets falling into one of three main categories: Orbital launch systems are rockets and other systems capable of placing payloads into or beyond Earth orbit. Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. For the list of predominantly solid-fueled orbital launch systems, see: Comparison of solid-fueled orbital launch systems. For the simple list of all conventional launcher families, see: Comparison of orbital launchers families. A first list contains rockets that are operational or in development as of 2022 a second list includes all retired rockets. This comparison of orbital launch systems lists the attributes of all individual rocket configurations designed to reach orbit. A Falcon Heavy launch vehicle from SpaceX