United Airlines has reintroduced 44 of its 52 of Pratt & Whitney PW4000-powered Boeing 777s, marking a significant milestone in the company’s recovery from an in-flight engine failure that grounded the fleet in February 2021.

Patrick Quayle, airline’s senior vice-president of international network and alliances, said that most of United’s 777 fleet was back in the air during the Cowen Global Transportation and Sustainable Mobility Conference on 7 September. 

“There has been terrific progress,” Quayle said. “We give credit also to Pratt and Boeing for being good partners and dedicating resources to solving the problem. Obviously, it took longer than anybody wanted, but in the end, it was a good collaboration between the three companies.”

United Boeing 777-200 PW4077 failure

Source: National Transportation Safety Board

Fire damage to the inboard side of the 777-200 PW4077 engine that failed on 20 February 2021.

The airline grounded its PW4000-powered 777s after one of its aircraft experienced a blade-out in-flight failure outside of Denver on 20 February 2021. Two fan blades had cracked due to metal fatigue, resulting in the loss of its starboard engine minutes after take off, showering neighborhoods below with debris. Nobody was injured, but it was the third such incident involving a PW4000 within three years.

The Chicago-based airline has been gradually ramping up its 777 operations this summer since receiving approval from the Federal Aviation Administration to reintroduce the aircraft in late May.

In March, Japan lifted its ban on all Pratt & Whitney PW4000-powered aircraft after imposing it for more than a year.