JP-5 (for "Jet Propellant") is a jet fuel that weighs 6.8 pounds per gallon and has a high flash point (min. 60 °C (140 °F)).
JP-8 is a jet fuel, specified in 1990 by the US government. It is kerosene-based. It is a replacement for the JP-4 fuel; the US Air Force replaced JP-4 with JP-8 completely by the fall of 1996, in order to use less flammable, less hazardous fuel for better safety and combat survivability. The US Navy uses a similar formula to JP-8, JP-5. JP-8 is projected to remain in use at least until 2025. It was first introduced at NATO bases in 1978.