Direct and indirect energy use for commercial aviation

Abstract Commercial aviation is important from an energy standpoint for two reasons. First, airplanes are the most energy-intensive mode for either freight or passengers. Second, airline traffic is growing much more rapidly than is overall intercity traffic. Thus airplanes are likely to consume a larger fraction of the transportation energy budget in the future than they do now. In 1971, fuel use for commercial airplane propulsion amounted to 1080 trillion B.t.u., 6·3 per cent of the transportation direct fuel use budget. This includes fuel used by both certificated and supplemental carriers. General aviation consumed an additional 100 trillion B.t.u. in 1971. Indirect energy uses for commercial air service—which includes energy used for petroleum refining, airplane manufacturing, repairs, maintenance, other fuels and electricity, food for passengers, etc.—totaled 370 trillion B.t.u. in 1971. Thus total energy demand for commercial air service in 1971 was 1450 trillion B.t.u. 2 per cent of the national energy budget. Aircraft fuel use accounts for three-fourths of total airline energy use. The energy associated with crude oil extraction, transportation, and refining adds another 15 per cent. Airplanes, engines, and parts; other fuels and electricity; food for passengers; and airport construction and maintenance each contribute only 1–3 per cent of total energy use.