Boeing has suggested that airlines ground all 777s with the type of engine that this weekend suffered a catastrophic failure over Denver, as United Airlines was ordered by US regulators to step up inspections of those aircraft.
Several airlines, including United, said that after one of the American carrier’s planes made an emergency landing at Denver International Airport on Saturday, they temporarily pulled the aircraft from service because its right engine blew apart just after take-off.
A Pratt & Whitney PW4000, part of the engine casing, rained down on suburban communities. None of the 231 passengers or 10 crew were injured on board, and the aircraft landed safely, authorities said.
In a statement Sunday based on an initial analysis of safety data, US Federal Aviation Administration Administrator Steve Dickson said inspectors “concluded that the inspection interval should be stepped up for the hollow fan blades that are unique to this model of engine, used solely on Boeing 777 airplanes.”
Dickson said it would possibly mean that some aircraft would be grounded, and Boeing said they should be before an inspection regime is defined by the FAA.
According to the financial newspaper Nikkei, Japan ordered the planes out of operations, claiming that an engine in the same family experienced trouble in December.
With the Pratt & Whitney 4000-112 engines in operation and another 59 in storage, Boeing said there were 69 777s.
According to the FAA, United is the only US airline with an engine in its fleet and has 24 of its aircraft in operations.
Two Japanese airlines have another 32 that are being pulled out, while nine, seven of which were in service, were grounded by Asiana Airlines until Boeing develops a strategy to address the problems.
Korean Air said it was debating whether 16 aircraft, 6 of which are in flight, should be grounded.
“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 released Sunday, referring to regulators from the United States and Japan.
It was sending a team to cooperate with investigators, the engine manufacturer said.
For Boeing, which saw its 737 Max planes grounded for more than a year after two deadly crashes in 2019, the emergency landing this past weekend is the latest concern. A great boost for the aircraft manufacturer, which lost billions during the Max grounding because it was unable to supply new aircraft to customers, the aircraft started returning to the skies late last year.
Saturday’s emergency video posted on Twitter shows the engine completely engulfed in flames as the plane soared through the air.
Freeze frames taken by a passenger seated slightly in front of the engine from various videos and also shared on Twitter seemed to show a damaged fan blade in the engine.
The passengers on their way to Honolulu said they were terrified that the aircraft would crash after an explosion and a burst of light, whilst the people on the ground saw large fragments of aircraft pouring down, missing only one house and crushing a truck. Visible from the ground, the explosion left a trail of black smoke in the sky.
The US National Transportation Safety Board said that two of the fan blades of the engine were damaged and “exhibited damage.” by the remainder of the fan blades. But it warned that it was too early to draw conclusions on what happened.
United says it will work closely with the FAA and the NTSB “to determine any additional steps that are needed to ensure these aircraft meet our rigorous safety standards and can return to service.”