FUEL-RELATED ISSUES CONCERNING THE FUTURE OF AVIATION

The paper discusses some major fuel-related issues which will influenc e the development of aviation over the next 50 years. Provided that gl obal economic development is not halted by world-scale war or crisis, the demand for civil air transport is likely to continue to expand. Th e consequent rising requirement for aviation fuel is considered in rel ation to the projection that the total oil extraction rate from relati vely accessible fields will reach a peak and then decline. The fuel op tions for aviation, against such a scenario, are explored. It is concl uded that if the aviation demand cannot be met economically from conve ntional oilfield sources, supplementation by kerosene-like fuel synthe sized from other feedstocks is much more likely, in the timeframe cons idered, than the radical step of a move to liquid hydrogen. The latter could be delayed until much later unless necessitated by constraints on carbon emissions. Other issues relating to aero-engine emissions ar e discussed, including the present uncertainties regarding the environ mental significance of injection into the atmosphere at aircraft opera ting altitudes. The implications of restricting operations to the trop osphere, to avoid the lower mixing rates of the stratosphere, are cons idered briefly.