Standards to promote airline fuel efficiency

This briefing summarizes the policy levers that exist under current U.S. statutes and regulations to accelerate airline fuel efficiency and collects a convenient reference guide to supporting research and analyses.

There are significant differences in fuel efficiency and carbon intensity across carriers and flights. The carbon intensity of airlines flying to and from U.S. airports varies by up to 26% over their networks, and by 50% and more on nonstop international flights. Differences of 80% or more have been observed at the route level.

The aviation industry has three main levers by which to improve fuel efficiency: (1) replacing older aircraft with newer, more fuel-efficient designs; (2) improving operations to carry more payload (passengers and freight) per flight and to fly more directly to destinations; and (3) finding optimal flight paths and avoiding congestion near airports via advanced air traffic management.

Airlines have historically questioned the need for greenhouse gas regulation, arguing that they already maximize fuel efficiency and that U.S. regulations should conform to the minimum international requirements proposed by the International Civil Aviation Organization (ICAO). But the airlines’ fuel-efficiency improvements are falling over time and have historically been dwarfed by increases in traffic. In 2016, ICAO proposed a CO2 (fuel efficiency) standard for new aircraft starting in 2020. ICAO member states, including the U.S., need to adopt a standard at least as stringent as ICAO’s in order for their manufacturers to continue selling aircraft internationally. Currently, there are no federal, state, or local fuel efficiency requirements for aircraft or airlines in the United States.

There are at least three options for applying a fuel efficiency standard to airlines:

  1. A pass/fail phaseout for individual in-service aircraft
  2. Tiered standards under which each airline would need to have an increasing share of their aircraft meet more stringent standards over time
  3. A declining fleet average standard.
Table 2: Options for regulating airline fuel efficiency