The fire in an aircraft engine of a Boeing 777-200 of the American airline United Airlines probably started on Saturday due to metal fatigue in the propeller. In metal fatigue, metal collapses under sustained stress, Robert Sumwalt of the US Airplane Safety Board (NTSB) said Monday.
The researchers want to know if there is a connection with an earlier incident in February 2018, when another United Airlines plane had a problem with an engine. Even then, metal fatigue was the cause.
The plane’s right engine, a United Airlines Boeing 777-200, caught fire four minutes after take-off on Saturday. On board were 231 passengers and ten crew members. The pilots decided – according to procedure – to turn off the burning engine and fly back on the remaining engine to Denver airport, from which it had taken off shortly before. The plane was able to land safely a little later. No one was hurt. No one on the ground was hit by the flying debris either.
The propeller’s components are now being transferred to a laboratory at Pratt & Whitney, the American company that made the aircraft’s engine. It will be investigated there on Tuesday under the supervision of researchers from the NTSB.
Relation to previous incidents
The focus of the research lies with engine builder Pratt & Whitney and experts expect little (financial consequences) for Boeing itself. The aircraft manufacturer previously suffered heavy losses due to problems with the Boeing 737-MAX, which had to be grounded for almost two years due to two fatal crashes.
Boeing recommended on Sunday to ground all Boeing 777 planes equipped with the same engines.
The American aviation authority FAA will soon issue an emergency instruction for technicians to check the propeller more often for metal fatigue. Following the earlier incident in 2018, airlines were required to inspect the engines for fatigue after every 6,500 flights.