WASHINGTON (Reuters) – A United Airlines plane with a Pratt & Whitney engine that failed on Saturday flew less than half of the flights allowed by U.S. regulators between fan blade inspections, two people with knowledge of the matter said.
The Boeing Co 777 aircraft flew nearly 3,000 cycles, the equivalent of a takeoff and landing, which compares with checks every 6,500 cycles required after a separate United engine incident in 2018, the sources said.
They sought anonymity because they were not allowed to speak publicly. United declined to comment.
Pratt, the maker of the PW4000 engines, advised airlines on Monday to increase checks every 1,000 cycles, in a bulletin seen by Reuters. He did not immediately respond to a request for comment.
On Tuesday, the US Federal Aviation Administration said it was ordering immediate inspections of 777 planes with PW4000 engines before they could return to the flight, going beyond Pratt.
The engines are used in 128 older versions of the plane, accounting for less than 10% of the more than 1,600 777s delivered and only a handful of airlines in the United States, South Korea and Japan were operating them recently.
Japan and South Korea have also suspended airplanes for checks on fan blades.
On Monday, the FAA acknowledged that after an incident with Japan Airlines’ PW4000 (JAL) engine in December, it was considering intensifying blade inspections that use thermoacoustic images to find signs of metal fatigue.
A risk assessment meeting was held last week to discuss the issue before United’s engine broke down on Saturday, one of the sources said, confirming an earlier CNN report. No decision was imminent before the United incident, the source added.
A spokeswoman for Pratt, owned by Raytheon Technologies, said on Wednesday that the fan blades would need to be sent to their repair station in East Hartford, Connecticut, for the latest inspections, including those in Japan and South Korea. South.
Each engine has 22 blades that must be removed individually and each will take eight hours to inspect, FAA administrator Steve Dickson told Bloomberg TV on Wednesday.
This equates to 352 hours of work per plane, as each 777 has two engines. Boeing said 69 of the planes were in service before Saturday’s incident, while 59 were stopped amid low demand during the pandemic.
Pratt did not answer questions about how many engines it could inspect per month. United did not comment on how long it expects the inspections to take, while JAL and ANA Holdings said the timing was unclear.
(This story corrects to remove the strange word ‘e’ in paragraph 11)
David Shepardson’s report in Washington; additional reporting by Tim Kelly in Tokyo, written by Jamie Freed. Gerry Doyle Edition