As availability and economics of jet fuels derived from crude oil become less certain in the future, the United States Air Force should consider the implications of utilizing aviation fuels derived from alternative energy resources. This paper examines the most promising energy alternatives to crude oil and the most attractive aviation fuels derivable from resource alternatives, with emphasis on coal-based aviation fuels. The findings suggest that coal and oil shale are the most promising energy resource alternatives. A synthetic jet fuel similar to jet fuels in use today appears to be the most attractive aviation fuel derivable from coal, primarily because it requires lower energy expenditures and results in a less costly product than the other alternatives, liquid hydrogen and liquid methane, while offering attractive characteristics for aviation applications. Despite its features, there are definite resource, capacity, and environmental constraints which could tend to limit the availability of synthetic jet fuels in the future.