Indonesian accident investigators said an airspeed indicator of a Boeing Co 737 MAX plane that crashed last week was damaged for its last four flights, but U.S. authorities responded cautiously to suggestions of fleet-wide checks.
The damage on a Lion Air jet that crashed into the sea, killing all 189 aboard, was revealed after data had been downloaded from the plane’s flight data recorder, Indonesia’s National Transportation Safety Committee (KNKT) chief Soerjanto Tjahjono told reporters on Monday.
His agency was asking Boeing and U.S. authorities what action to take to prevent similar problems on this type of plane around the world, he added.
“We are formulating, with NTSB and Boeing, detailed inspections regarding the airspeed indicator,” he said, referring to the U.S. National Transportation Safety Board.
The acting administrator of the U.S. Federal Aviation Administration (FAA), Dan Elwell, said the FAA and NTSB had teams of experts in Indonesia at the government’s request.
“Any action the FAA would take regarding that incident would have to wait until we have findings, until we have information,” Elwell said in Washington.
Indonesia has not formally requested fleet-wide checks on 737 MAX jets and none are planned pending more data, a person familiar with matter said, on condition of anonymity.
Investigators have not disclosed any reports of other airspeed failures on the aircraft.
The FAA, which regulates the U.S. aviation industry, has not received any reports of airspeed issues with the model in the United States, said a person familiar with its reviews, who asked not to be named as he was not authorised to speak.
It was not immediately clear whether the problem with the crashed jet stemmed from a mechanical or maintenance issue.
“We don’t know yet where the problem lies, what repair has been done, what their reference books are, what components have been removed,” said Nurcahyo Utomo, the KNKT sub-committee head for air accidents.
“These are the things we are trying to find out: what was the damage and how it was fixed.”
Safety experts say it is too early to determine the cause of the crash on Monday last week of the flight from Jakarta to the tin-mining town of Pangkal Pinang.
Authorities have yet to recover the jet’s cockpit voice recorder from the sea floor, just northeast of Jakarta, where the plane crashed 13 minutes into its flight.
Boeing declined to comment. The U.S. manufacturer has delivered 219 737 MAX jets to customers globally, its website shows, with 4,564 orders for jets yet to be delivered.
The Boeing 737 MAX is a more fuel-efficient version of the manufacturer’s popular single-aisle jet.
The Lion Air crash was the first involving the type of plane, which airlines introduced into service last year.