HERNDON, Virginia: In this file photo, an inspector for Pritt and Whitney engines checks a United Airlines Boeing 777 after it made its inaugural flight from Heathrow Airport in London to Washington Dulles International Airport on June 7, 1995. - AFP

NEW YORK: Boeing confirmed yesterday that dozens of its 777 aircraft were grounded worldwide, while Britain announced a temporary ban on those jets following a weekend scare involving a United Airlines plane in Colorado. The incident on the flight out of Denver - which quickly returned to the airport after part of the engine caught fire and broke off - prompted United and other airlines to ground the planes with the same Pratt & Whitney engine.

While no one was injured in the Denver incident, the episode is the latest setback for Boeing, which only recently resumed deliveries of the long-grounded 737 MAX following two fatal crashes of that plane. Shares of Boeing shook off early weakness yesterday as aviation experts said the incident mostly raised pointed questions about Pratt & Whitney and United over engine maintenance.

"It's nothing like the MAX," said Teal Group aviation analyst Richard Aboulafia. "After all these years of service it is unlikely to be a design issue with the engine, certainly it is something to do with maintenance." Boeing said all 128 of the 777 models with Pratt & Whitney engines were grounded following Saturday's emergency landing of United flight 328 to Hawaii.

"I have just had confirmation that all the 777s equipped with this engine have been grounded," a spokeswoman for the planemaker told AFP in a text message yesterday. And British Transport Secretary Grant Shapps announced a temporary ban on jets with Pratt & Whitney 4000-112 series engines from entering UK airspace. "I will continue to work closely with the (UK Civil Aviation Authority) to monitor the situation," he tweeted.

The Denver incident comes on heels of a similar problem in Japan in December. A video shot from inside the United aircraft - which had 229 passengers and 10 crew on board - showed the right engine ablaze and wobbling on the wing of the Boeing 777-200. Residents in the Denver suburb of Broomfield found large pieces of the plane scattered around their community.

The US Federal Aviation Administration (FAA) has ordered extra inspections of some passenger jets after the incident. "I have directed them to issue an Emergency Airworthiness Directive that would require immediate or stepped-up inspections of Boeing 777 airplanes equipped with certain Pratt & Whitney PW4000 engines," FAA chief Steve Dickson said in a statement.

Dickson said a preliminary safety data review pointed to a need for additional checks of the jet engine's fan blades, which were unique to the model and only used on 777 planes. Officials from the FAA met with Pratt & Whitney and Boeing representatives on Sunday evening, he added. The US National Transportation and Safety Board (NTSB) said a preliminary investigation indicated two fan blades fractured on the number 2 engine on the plan.

"The airplane sustained minor damage," the NTSB said in a statement Sunday. "The examination and documentation of the airplane is ongoing." Pratt & Whitney said it was cooperating with the NTSB probe and "will continue to work to ensure the safe operation of the fleet". United said Sunday it was removing the aircraft from its schedule, "and will continue to work closely with regulators to determine any additional steps".

Japan's transport ministry earlier said it had ordered stricter inspections of engines after a Japan Airlines 777 plane flying from Haneda to Naha experienced trouble with "an engine in the same family" in December. Asiana Airlines, South Korea's second-largest carrier, also said it would not fly any of its seven currently operational 777s.

The engine failure is unwelcome news for Boeing, which only recently resumed deliveries of the 737 MAX following a 20-month global grounding after two tragic crashes killed 346 people. The MAX began returning to commercial service in late 2020, a time when commercial airline travel remains depressed due to the coronavirus pandemic. Boeing executives said last month they expect it will take about three years for activity to return to pre-pandemic levels.

Michel Merluzeau, an expert at consultancy AIR, agreed the latest problem did not appear to result from poor plane design by the aerospace giant. "It's not really a problem for Boeing," he said. "It's more an issue of maintenance - how United or Pratt & Whitney is maintaining engines that have been in use for a while". - AFP