Lax Safety, Faulty Systems Cited in Indonesian Crash of Jet
(Bloomberg) -- Poor safety procedures and the inability of pilots to gain control of a malfunctioning airplane may have contributed to the crash of Lion Air flight JT610 that killed 189 people, according to a preliminary report by Indonesian investigators.
During the 11 minute flight before the doomed plane crashed into the Java Sea, the pilots battled with an automatic safety system that was relying on faulty instruments that hadn’t been properly fixed despite similar failures on the plane’s previous flight from Bali. The report from Indonesia’s National Transportation Safety Committee, based on information from the plane’s “black box” data recorder, ATC records, interviews with prior crews and other logs, criticized Lion Air’s safety culture and said pilots must be allowed to decide if they want to continue a flight.
Boeing Co., maker of the plane, said in a statement Wednesday that the 737 Max series of jets are “as safe as any airplane that has ever flown.”
“Both the flights, from Bali to Jakarta and the final trip, suffered from different airspeed, altitude and angle of attack readings,” Nurcahyo Utomo, the lead investigator at NTSC, told reporters in Jakarta on Wednesday. He said the pilots on the flight from Bali the previous day should not have flown the plane to Jakarta, but should have turned back.
The flight’s second black box -- the cockpit voice recorder -- hasn’t yet been found and the preliminary report doesn’t offer a cause for the accident. But it provides the most detailed look so far into the chaotic minutes before the plane vanished from radar on its way to the Indonesian island of Bangka.
The measures recommended by the regulator put Indonesia’s patchy aviation safety record back in the spotlight. The nation’s airlines, including Lion Air, were banned from flying to the European Union and the U.S. for almost a decade until 2016 because of safety concerns.
Lion Air President Director Edward Sirait said the crashed jet was certified airworthy by technicians in its final two trips and the airline was concerned about some reports to the contrary. The airline will implement the safety recommendations made by NTSC, he said.
“Maybe people think that we are not a bonafide airline, but we work according to rules,” Sirait told reporters in Jakarta. “We do have Boeing representatives at our office. There are four of them.”
Boeing said in a statement that it’s working closely with investigators, and referred all questions about the crash to the NTSC.
The pilots commanding the doomed plane appeared not to understand what was happening to them as they radioed air traffic controllers asking for their altitude and speed. They said they had an unspecified “flight control problem,” according to the report.
At the center of the ongoing investigation into the nation’s worst air disaster in two decades is a sensor that measures how high or low the plane’s nose is pointing relative to the oncoming air -- its so-called angle of attack. That angle is critical to preventing the plane from stalling and the 737 Max includes a safety system called the Maneuvering Characteristics Augmentation System that takes control and forces the nose down if sensors detect a stall may occur.
The NTSC investigation shows that throughout the flight faulty sensors were feeding the system incorrect readings and the pilots were continually battling to prevent it from forcing the nose of the plane down right up until the crash.
Problems with sensors on the jet had been reported on three previous flights the plane made, including one the day before the crash, from Bali. A mechanic had worked on other sensors and equipment overnight once the plane reached Jakarta, before the plane took off again in the morning, but not on the angle-of-attack vane that was replaced the previous day, according to the NTSC.
The pilot and co-pilot on the two flights reacted differently to the multiple errors messages and malfunctions. On the flight from Bali to Jakarta, the flight crew shut off the motor that was trying to push down the nose. The pilots on Flight 610 didn’t take that step -- which is part of a long-standing emergency procedure.
Before Wednesday’s preliminary report, the three largest U.S. pilot unions had voiced concern over what they said was a lack of information about MCAS, the little-known anti-stall feature, which in limited circumstances, lowers the jet’s nose without any input from pilots.
Boeing has maintained that pilots already had been trained to respond to that behavior by the plane.
The NTSC said the actions from the pilots on the previous flights have been forwarded to Boeing with recommendations for operators to address the issue when faulty sensors cause problems with the MCAS.
Boeing climbed 2 percent to $324.39 at 9:46 a.m. in New York after advancing as much as 3.4 percent for the biggest intraday gain in four weeks.
Jakarta-based Lion Air, owned by closely held PT Lion Mentari Airlines, is among Boeing’s biggest Asian customers, placing an order in 2012 for 201 of the manufacturer’s new 737 Max jets as well as 29 extended-range 737-900s in a deal worth $22.4 billion at list prices.
Several Lion Air aircraft have been damaged beyond repair. The most recent was in 2013, when a two-month-old Boeing 737-800 landed in the water short of a runway in Bali.
Indonesian investigators expect to fly to the U.S. later this week to gather more information about the Boeing aircraft and its components, including discussing the MCAS safety feature with Boeing engineers to understand how it may have contributed to the accident, Utomo said.
©2018 Bloomberg L.P.