Prospects for liquefied natural gas and other alternative fuels for future civil air transportation

Fundamental issues related to the possible introduction of liquid methane, propane or butane fuelled civil passenger transport aircraft are addressed. It is proposed that partial transition to one, or a mixture, of these alternative fuels may provide an operational interim option when supplies of Avtur become prohibitively expensive. Preliminary criteria to determine the suitability of alternative fuels are also included.