JP54 stands for “Jet Propulsion, A1, Colonial Grade 54″. When crude oil is being refined, only 15% of it is made up of JP54 and the rest of the grade is used for different types of plastic. Colonial grade JP54 was developed by JP Morgan, and was later replaced by AVGAS also known as AVGAS100LL. It’s the lowest sulphur content kerosene used worldwide. JP54 powers gas turbine aircraft engines. Generally, a number of different mixtures make up jet fuel and this relates to flash points and how the carbon numbers are distributed.