News: Damage to United Boeing 777 engine consistent with metal fatigue: NTSB.
WASHINGTON (Reuters) – Robert Sumwalt, chairman of the U.S. National Transportation Safety Board (NTSB), said Monday that damage to a fan blade in a Pratt & Whitney engine that failed on a United Airlines Boeing 777-200 was loud a preliminary report is compatible with metal fatigue assessment.
At a press conference, Sumwalt said it was not clear whether the failure of the PW4000 engine on Saturday with a “loud bang” four minutes after takeoff was in line with another engine failure on another flight to Hawaii in February 2018, which was on a break in a fan blade can be attributed to fatigue.
The engine that failed and spilled parts over a suburb of Denver on the 26-year-old Boeing Co 777 was a PW4000, which was used in less than 10% of the global fleet of 777 wide-body jets.
In another incident on Japan Airlines (JAL) 9201.T 777 with a PW4000 engine in December 2020, the Japanese Transport Safety Board reported finding two damaged fan blades, one with a metal fatigue crack. An investigation is still ongoing.
The focus is more on engine maker Pratt & Whitney, and analysts expect little financial impact on Boeing. However, the PW4000 issues are causing new headaches for the aircraft manufacturer as it recovers from the far more severe 737 MAX crisis. Boeing’s flagship narrowbody jet was on the ground for almost two years after two fatal crashes.
The United engine’s fan blade will be examined Tuesday after it was flown to a Pratt & Whitney lab where it will be examined under the supervision of NTSB investigators.
“What’s important is that we really really understand the facts, circumstances and conditions surrounding this particular event before we can compare it to any other event,” said Sumwalt.
Boeing recommended that airlines cease using the aircraft while the FAA put an appropriate inspection protocol in place, and Japan imposed a temporary suspension of flights.
The Federal Aviation Administration plans to issue an emergency airworthiness policy shortly that will require increased inspection of fan blades for fatigue.
The FAA ordered inspections every 6,500 cycles in March 2019 after the United engine failed in February 2018 due to fan blade fatigue. A bicycle is a take-off and a landing.
Sumwalt said the United incident was not viewed as uncontrolled engine failure as the safety ring contained the parts when they flew out.
There was minor damage to the aircraft body, but no structural damage, he said.
NTSB will investigate why the hood parted from the aircraft and why a fire broke out despite signs that the engine was turned off fuel, Sumwalt added.
Pratt & Whitney, owned by Raytheon Technologies Corp., said Sunday it had lined up with regulators to review inspection logs.
Almost half of the global fleet of 128 aircraft operated by airlines such as United, JAL, ANA Holdings, Korean Air and Asiana Airlines had already stalled due to falling demand for travel due to the coronavirus pandemic.
Reporting by David Shepardson in Washington and Jamie Freed in Sydney; additional reporting by Tracy Rucinski in Chicago Editing by Kim Coghill and Gerry Doyle
Original Source © Reuters