The aviation sector is widely known to be a high-emissions industry, with aircraft contributing to a growing pollution problem – but United Airlines just made history, in a brilliant way

United Airlines on Wednesday operated the world’s very first flight that used 100% sustainable aviation fuel, known as SAF.

Flying a jet with more than 100 passengers from Chicago to Washington, DC, the flight was the first commercial flight ever using only renewable fuel.

In a statement United Airlines said: United is the world leader in the usage and support for the development of SAF, an alternative fuel made with non-petroleum feedstocks, already having agreements to purchase nearly twice as much SAF as the known agreements of all other global airlines combined.

SAF has the potential to deliver the performance of petroleum-based jet fuel but with a fraction of its carbon footprint, and according to the U.S. Department of Energy, the country’s vast feedstock resources are enough to meet the projected fuel demand of the entire U.S. aviation industry.

Currently, airlines are only permitted to use a maximum of 50% SAF

The SAF used on the Dec. 1 flight is drop-in ready and compatible with existing aircraft fleets, United said.

The flight operated as a demonstration – to see how the jet would perform using only SAF fuel

The 737 MAX 8 used 500 gallons of SAF in one engine and the same amount of conventional jet fuel in the other engine “to further prove there are no operational differences between the two and to set the stage for more scalable uses of SAF by all airlines in the future,” United said.

United partnered with other companies including Virent, a subsidiary of Marathon Petroleum whose technology enables 100% drop-in SAF, and World Energy, the world’s first and North America’s only commercial SAF producer to make the flight possible.