In 1965 Pratt & Whitney aircraft tested the safety of LNG (liquified natural gas) as an aircraft fuel. This video documents that test.
First test: 100 gallons LNG is poured on earth and a flare is passed through the vapor cloud to ignite it.
Second test LNG and Diesel (Jet Fuel) are poured on a hot surface
Third test: LNG and Diesel are poured on ignition surfaces
Fourth test: LNG container is shot multiple times with a .50 cal incendiary round
Fifth test: LNG in beaker is exposed to lit cigarette
