■ Boeing recommends that all 777s with the type of engine that blew apart over the weekend be grounded.
Plane pulled from service after engine failure
Boeing has recommended that airlines ground all 777s with the type of engine that blew apart after takeoff from Denver over the weekend, and most carriers that fly those planes said they would temporarily pull them from service.
The U.S. Federal Aviation Administration ordered United Airlines to step up inspections of the aircraft after one of its flights made an emergency landing at Denver International Airport on Saturday as pieces of the engine’s casing rained on suburban neighborhoods. None of the 231 passengers or 10 crew were hurt, and the flight landed safely, authorities said. United is among the carriers that has grounded the planes.
FAA Administrator Steve Dickson identified the focus on the steppedup inspections as hollow fan blades unique to the Pratt & Whitney PW4000 engine model and used solely on Boeing 777s. Dickson’s statement said the conclusion was based on an initial review of safety data and would likely mean grounding some planes.
Robert Sumwalt, chairman of the National Transportation Safety Board, said during a virtual news conference Monday that a fractured fan blade found in the engine had visible signs of “damage consistent with metal fatigue.” The broken blade hit and fractured the blade next to it as the engine broke apart, according to a preliminary investigation. Sumwalt said the blade that fractured first was being flown on a private jet to Pratt & Whitney’s headquarters Monday night to be examined under the supervision of NTSB investigators.
“Our mission is to understand not only what happened, but why it happened, so that we can keep it from happening again,” he said.
Boeing said there were 69 777s with the Pratt & Whitney 4000-112 engines in service and 59 in stor
age and affirmed they should be grounded until the FAA sets up an inspection regime.
United had 24 of the planes in service; it is the only U.S. airline with the engine in its fleet, according to the FAA.
Two Japanese airlines have another 32. Japan ordered the planes out of service, according to the financial newspaper Nikkei, while noting that an engine in the same family had trouble in December.
In South Korea, Asiana Airlines grounded nine, seven of which were in service, and Korean Air said it
grounded 16 aircraft, six of which are in service.
“We are working with these regulators as they take actions while these planes are on the ground and further inspections are conducted by Pratt & Whitney,” Boeing said in a statement, referring to American and Japanese regulators.
The engine maker said it was sending a team to work with investigators.
Video posted on Twitter from Saturday’s emergency showed the engine engulfed in flames as the plane flew. Freeze frames from different video taken by a passenger sitting slightly in front of the engine and posted on Twitter appeared to show a broken fan blade in the engine.