It has been hailed as ‘historical’ and ‘making aviation history’ by those directly involved and in a way it was, but United Airline’s first flight with passengers on 100 percent sustainable aviation fuel (SAF) actually wasn’t what the press statements wanted us to believe. United’s ‘historical’ flight is push for pure SAF.
Yes, the Boeing MAX 8 N77259 did fly on pure SAF but only on the number two CFM LEAP-1B engine. The other engine used conventional Jet-A1 kerosene. Each tank had 500 gallons (2.273 liters) of fuel, with the pure SAF provided by World Energy and the necessary aromatics coming from Virent’s BioForm synthesized aromatic kerosene (SAK) derived from plant sugars. While 500 gallons sounds little, AirInsight checked with sources that it was sufficient to do the 1 hour 24 minutes the trip from Chicago to Washington Reagan National Airport.
Yes, it was also the first flight using pure SAF with passengers on board, 115 to be exact. That’s not ‘full of passengers’ as United’s press release says. But this wasn’t a regular commercial service. UA2701 was qualified as an ‘experimental’ flight, as the decal next to door 1 on the MAX 8 confirmed, with non-paying passengers like United CEO Scott Kirby, GE Aviation CEO John Slattery, other company representatives, and invited journalists.
Pure SAF test flight done in October
No, it wasn’t the first United flight using pure SAF. As Virent points out in a press release on October 15, two days earlier it did the same during a flight test to demonstrate unblended SAF on one engine and conventional kerosene on the other. The release didn’t specify the aircraft type, but as part of the same test program, this must have been a United MAX too. Virent President Dave Kettner said in October that the flight had demonstrated that 100 percent SAF could be used with no modification to the aircraft or engine and will support approval of SAK by ASTM International, which approves new aviation fuels. Virent produces SAK in its demonstration plant in Madison (Wisconsin).
But even after getting the facts straight, the message is that United Airlines, Boeing, CFM, World Energy, and Virent all want to push for 100 percent SAF in their quest to reduce the carbon footprint of aviation. United says its Eco-Skies program that gives customers the opportunity to buy SAF has resulted in seven million gallons having been purchased since its launch in April. Eco-Skies now includes over thirty participants, like DHL, HP, Nike, Maersk, Microsoft, and Visa. United also announced the purchase of 1.5 billion SAF from Alder Fuels and is a partner in Fulcrum BioEnergy, which completed the construction of its biofuel plant in Sierra in July.
oneworld also commits to more SAF uptake
But United isn’t alone in committing to SAF. In September, US airlines committed to taking up fifty percent more SAFs in 2030. On November 30, the oneworld alliance that includes fourteen airlines like British Airways, American Airlines, Alaska Airlines, Cathay Pacific, and Finnair, said it intended to purchase 350 million gallons of SAF from Aemetis at San Francisco International Airport. American Airlines said it will take almost one-third of this or 120 million gallons or sixteen million gallons per year for seven years, the duration of the oneworld contract that starts in 2024. It covers a blend of forty percent SAF and sixty percent Jet A-fuel. Oneworld said earlier that its members want to use ten percent of all fuel used in 2030 to be SAFs.
But as United’s Kirby pointed out to Bloomberg, getting to ten percent pure SAF in 2050 will require an investment of $250 billion and even $1.15 trillion if the airline industry wants to move entirely to unblended SAF. That’s money the airlines will never have, so Kirby called on governments to introduce incentive schemes and tax credits to build the industry framework for sustainable fuels. Something the Biden Administration is already doing.
The airlines association, IATA, said in October at its Annual General Meeting in Boston that SAF production would have to increase from 7.9 billion liters in 2025 to 91 billion in 2035 and to 449 billion liters in 2050 to meet demand. While very ambitious this target is realistic, said Director-General Willie Walsh, but like Kirby yesterday he called for government support to create the industrial infrastructure.
