RP-1 (Refined Petroleum-1) (C₁₂H₂₄ (approximate average)) is a hydrocarbon propellant used as a fuel. Storable at ambient temperature. Typical ISP: 270–340 s (with LOX) seconds.
RP-1 is a highly refined form of kerosene used as rocket fuel, standardized by the US military as MIL-DTL-25576. It offers excellent density, storability, and handling characteristics compared to cryogenic fuels, making it ideal for first-stage applications. RP-1 powers many of the world’s most successful rockets including Falcon 9, Atlas V, and Soyuz.
Developed in the 1950s to replace ethanol and provide consistent performance. Specified by the US military for rocket use, it became the dominant hydrocarbon rocket fuel worldwide.
High density, storable, safe handling, low cost, well-understood combustion
Lower Isp than hydrogen, coking at high temperatures, soot production
