United Airlines Makes History, Flies a Passenger Aircraft with 100% Sustainable Fuel

And it traveled 612 miles.
Ameya Paleja
United's greener aviation is airborne.gk-6mt/iStock

A United Airlines passenger aircraft touched down at the Reagan National Airport in Washington, DC on December 2, 2021, like any other Boeing 737 Max 8 aircraft would. However, the flight that traveled 612 miles (984 km) on this trip made aviation history as it was the first commercial aircraft to be powered by 100 percent sustainable aviation fuel (SAF), CNET reported.

SAF is a biofuel that is made using renewable biomass and products generally discarded as waste. According to the Department of Energy website, the U.S. can produce up to 60 billion gallons of SAF from one billion dry tons of biomass every year. The fuel, thus generated, that can be used directly in combustion engines contains lesser carbon than fossil fuels and can aid in reducing greenhouse gas (GHG) emissions from aviation and the transportation industry, at large. Interestingly, the fuel also contains fewer aromatic compounds and burns cleaner in aircraft engines. 

Current regulations in the U.S. aviation industry allow aircraft to use up to 50 percent of SAF on aircraft, United Airlines told CNET. So, United Airlines sought special permission to fly one engine using 100 percent SAF while the other used conventional fuel.  When that was granted, a new Boeing 737 Max 8 aircraft was used to ferry 100 passengers and executive staff from United, Boeing, and Virent, the manufacturers of the drop-in SAF, a press release said.

The flight that traversed 612 miles also demonstrated that there were no operational differences between the SAF and conventional fuel, even as the SAF emitted up to 75 percent less carbon on the trip, United told CNET. 

Earlier this year, United also launched the Eco-Skies Alliance Program under which it has committed to purchasing more than seven million gallons of SAF in 2021. United claims that this will reduce 66,000 metric tons of GHG that would be released if conventional fuel was used.

According to the press release, United has now signed up 12 new participants to this program that include popular names like Maersk, Meta, Microsoft, Salesforce, and Visa among others, who have agreed to purchase SAF for their requirements.