Boeing has urged airlines to ground 120 of its 777 type aircraft after the engine on a United Airlines flight caught fire and fell apart over Denver.
The manufacturer said airlines using planes with the same engine type should suspend operations until full inspections could be carried out, after the United plane was forced to make an emergency landing having scattered debris over residential areas below.
The engine on flight 328 from Denver to Honolulu failed shortly after takeoff on Saturday, with 231 passengers and 10 crew on board. Pilots issued a mayday call and returned to Denver. Police expressed astonishment that no one had been killed or injured on the ground after large pieces of debris landed near houses and in public parks.
Five airlines worldwide use the same 777 model with Pratt & Whitney PW4000 engines. United Airlines said it was temporarily grounding all 24 of its Boeing 777s in current service. Japan’s aviation regulator told Japan Airlines (JAL) and All Nippon Airways (ANA), which between them operate 32 of the affected model, to ground their planes. South Korea, home to the remaining carriers, said it was monitoring the situation.
The 777-200s and 300s affected are older and less fuel efficient than the models used by most operators, including British Airways, whose 59 777s do not have the Pratt & Whitney engines.
Boeing said 69 of the planes were in service and 59 in storage as a result of lack of demand during the coronavirus pandemic.
The US Federal Aviation Administration had issued an emergency directive to require immediate or enhanced inspections of similar 777 models to the one involved in the Denver incident, before Boeing went further to urge the planes were grounded.
The US manufacturer has faced intense scrutiny over its safety record since the 737 Max disasters Indonesia and Ethiopia, in which 346 people died. The 737 Max has only returned to service in the past two months, almost two years after being grounded.
Initial examination of the Denver 777 engine showed that two fan blades had fractured, accorded to the US National Transportation Safety Board. Flight data recorders have been taken to a lab in Washington for analysis.
A malfunction with the same engine forced a JAL internal flight to return to Naha in December, Japan’s transport ministry revealed on Monday, on a 777 of the same age as the Denver plane.
A further engine failure occurred at the weekend on a Boeing 747 cargo plane in the Netherlands. Dutch authorities are investigating after parts fell from the engine shortly after the plane took off from Maastricht for New York on Saturday.
The plane, also using a Pratt & Whitney engine, a smaller version of the PW4000 model according to Reuters, made an emergency landing at Liège in Belgium. The engine caught fire, witnesses said, and scattered small metal parts over the southern Dutch town of Meerssen, damaging cars and slightly injuring one woman, according to local media reports.
Pratt & Whitney, which is owned by Raytheon Technologies, said after the United flight that it was “actively coordinating with operators and regulators to support the revised inspection interval” of its engines for the 777.