Google and American Airlines Use AI to Cut Contrail Formation by 62%

When aircraft pass through cold, humid airspace, exhaust particles can condense into clouds of ice crystals. Some persist for hours and trap heat emitted from Earth's surface. Since 2023, Google Research has worked with American Airlines and Breakthrough Energy to train AI using satellite, weather and flight data. Contrails account for more than one-third of aviation's warming impact, making avoidance of contrail-forming areas a potentially low-cost climate measure.

Google released the results on March 19, 2026. From January to May 2025, American Airlines integrated AI forecasts into the Flightkeys system and tested them on 2,400 transatlantic flights between the United States and Europe. The 112 flights that actually used avoidance routes recorded 62% less contrail formation than the control group and about a 69% reduction in warming impact. Fleetwide fuel consumption was estimated to increase by 0.3%, while the climate benefit was 20 times the warming impact of the additional fuel. The cost of deployment was not disclosed.