JP-7 (Jet Propellant 7, MIL-T-38219)'s a jet fuel developed by the U.S. Air Force for use in supersonic aircraft because of its high flashpoint and thermal stability. It's the fuel used in the Pratt & Whitney J58 engines, used in the Lockheed SR-71 Blackbird. The air compression of Mach 3+ cruising flight generates very high skin temperatures, therefore this special fuel was needed. The story told by Ben Rich in his book Skunk Works's that a lit match can be dropped in a bucket of JP-7 and the… (More on Jp-7)