fuels and SI
Current use
Here are some common liquid fuel combinations in use today:
- LOX and kerosene (RP-1). Used for the lower stages of the Soyuz boosters, and the first stage of the U.S. Saturn V, Atlas, and Falcon 9 boosters. Very similar to Robert Goddard's first rocket.
- Nitrogen tetroxide (N2O4) and UDMH or MMH. Used in three first stages of the Russian Proton booster, most Chinese boosters, a number of military, orbital and deep space rockets, as this fuel combination is hypergolic and storable for long periods at reasonable temperatures and pressures.
- hydrazine(N2H4) and Aerozine-50 are also used in deep space missions because they are storable and hypergolic, and can be used as a monopropellant with a catalyst.
Typical performances of common propellants Propellant mix Vacuum Isp (seconds) Effective exhaust velocity (m/s)
liquid oxygen/
liquid hydrogen 455 4462 liquid oxygen/
kerosene (
RP-1) 358 3510
nitrogen tetroxide/
hydrazine 344 3369