Jet engines burn fuel to create propulsion via explosive thrust. But an explosion can be dangerous to the machine and its passengers, so jet fuels utilize a sophisticated mixture to avoid accidental ignition.
Commercial jet fuel is made of specially treated kerosene. It is given additives that protect it from ignition by unintended sources, such as static electricity, extreme cold and trace metals.
A compound's flash point is the temperature required for it to produce the vapors needed for ignition. Commercial jet fuel has a relatively high flash point of 100 degrees F, allowing for safe handling.
After the jet fuel reaches its flash point, it must then be heated to its auto-ignition temperature, where it will automatically combust without the need of an outside ignition source. The auto-ignition temperature of jet fuel is 410 degrees F.