Motivated by concerns over rising costs of Jet-A fuel and the current limitations of “drop-in” fuel substitutes, it is proposed that methane (LCH₄) provides a promising sustainable aviation fuel alternative. Following consideration of current aircraft fuel costs, a modified preliminary Life Cycle Costing Analysis is provided for a proposed liquid methane aircraft, providing direct economic comparison to a current comparator aircraft with regards to the annual fuel cost, aircraft acquisition costs and the cost of required airport infrastructure. Finally, a preliminary evaluation of the financial benefits of a transition to liquid methane fuel in the aviation sector is presented.