United Airlines has set a lofty goal of being the industry leader in fuel efficiency.
It has a target of cutting greenhouse gas emissions by 50% over the next couple of decades and said it will invest more than $2 billion a year in refreshing its fleet with more fuel-efficient aircraft.
It is expanding the use of lower carbon biofuels with immediate effect.
Flight 44 from San Francisco to Zurich will use about 16,000 gallons of a biofuel blend, which United says is the longest flight yet by a US airline using at least a 30/70 blend of biofuel.
"This is not only good for the environment but guards against oil price instability," said Aaron Stash, manager of environmental strategy and sustainability at United.
The goal of halving emissions by 2050 would be the equivalent of taking about 4.5 million cars off the road each year.
United says it wants to be ‘the world’s most environmentally conscious airline’ but has some way to go before it can seriously claim that title.
Newer more fuel efficient jets will help.
A recent study showed Norwegian Air leads the way in fuel efficiency out of 20 carriers serving transatlantic routes.
This is down to its mostly new fleet of Boeing 787 Dreamliner and Boeing 737 MAX aircraft.
