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US-AVIATION-AEROSPACE-ACCIDENT
FAA considered grounding some Boeing 737 Max planes last year: source
NEW YORK, April 29, 2019 (BSS/AFP) – US regulators considered grounding
some Boeing 737 MAX planes last year after learning of a problem with a
system that is now the main suspect in two deadly crashes, a source close to
the matter said.
Investigators in the Lion Air crash in October off the coast of Indonesia
and the Ethiopia Airlines disaster in March have zeroed in on the planes’
anti-stall system, called the Maneuvering Characteristics Augmentation
System, or MCAS.
Last year, inspectors with the Federal Aviation Administration discovered
Boeing de-activated a signal designed to advise the cockpit crew of a
malfunctioning of the MCAS system, the source said.
The inspectors were in charge of monitoring Southwest Airlines, the biggest
user of 737 MAX planes, with a fleet of 34 of them at the time, added the
source.
Before the Lion Air crash, which killed all 189 people on board, “the
(signals) were depicted as operable by Boeing on all MAX aircraft” regardless
of whether the cockpit crew thought they had them turned on or off, said a
Southwest spokeswoman.
She said after the accident, Boeing told Southwest the signals were “turned
off unless they were specifically designated as being turned on” — prompting
the airline to choose that option for all its aircraft.
It was at that point inspectors learned Boeing had opted to make the
malfunction alert an optional extra costing more money — and had deactivated
the signal on all 737 MAX delivered to Southwest without telling the carrier.
They considered recommending grounding the planes as they explored whether
pilots flying the aircraft needed additional training about the alerts, said
the source.
They decided against that — but never passed details of the discussions to
higher-ranking officials in the FAA, the source said, confirming a story in
The Wall Street Journal.
– A costly grounding –
The FAA would not comment on the planes coming close to being grounded last
year.
The Ethiopia Airlines crash left all 157 people on the plane dead and led
to all Boeing 737 Max planes all over the world being grounded. In this case
too the MCAS is being looked at as a possible cause of the crash.
In times of mid-air distress, the system is supposed to activate on its own
and push the nose of the plane down to keep it from stalling.
Boeing is working on changing the MCAS so it can get the planes back in the
air.
The grounding has already cost the carrier a billion dollars, Boeing said
last week.
But the bill will probably climb because Boeing is expected to pay money to
airlines forced to cancel thousands of flights and hire more reservations and
services staff.
Boeing has suspended deliveries of Boeing 737 Max planes and cut production
of them by 20 percent.
Neither of the Boeing 737 Max planes in the Lion Air crash in Indonesia or
the Ethiopian Airlines crash were equipped with the signal that is supposed
to show a malfunctioning of the MCAS, an industry source told AFP in March.
Called “disagree lights” in Boeing parlance, these lights turn on when
faulty information is sent from so-called angle of attack sensors to the
MCAS. Those sensors monitor whether the wings have enough lift to keep the
plane flying.
“As we return to service, all customers will have the AOA disagree alert as
standard and have the option to include the AOA indicator at no cost. This
change will be made to all MAX aircraft — production and retrofit,” Boeing
told AFP in a statement Sunday.
“A new software update will separate those two features, making AOA
disagree alert a standalone standard feature and keeping AOA indicator as an
additional customer-selected option.”
In the case of the Lion Air crash, investigators think one of the angle of
attack sensors may have failed and sent incorrect data to the MCAS, causing
its nose to go down as pilots fought to bring it back up.
The MCAS overrides the pilots manual efforts to point the plane up or down.
With the angle of attack sensor not working properly, the thing to do would
have been to turn off the MCAS. But the Lion Air cockpit crew did not know
that.
BSS/AFP/MSY/0829 hrs