Boeing cites airline error in Indonesian crash

Families of passengers on the crashed Lion Air flight look at belongings recovered from the sea

Families of passengers on the crashed Lion Air flight look at belongings recovered from the sea

The KNKT said MCAS was not described in the Lion Air flight manual before the crash, nor in those used by American airlines according to United States pilot unions.

The aircraft used for Lion Air flight JT610, which crashed into the Java Sea during a flight to Pangkalpinang, Bangka Belitung Islands, from Jakarta on October 29 was in bad condition during previous flights, the National Transportation Safety Committee (KNKT) has revealed. This sequence continues for the rest of the flight.

But, according to the preliminary report, problems continued.

The Oct. 29 struggle against the automatic system, known as the Maneuvering Characteristics Augmentation System, or MCAS, was unsuccessful.

The data also shows that the aircraft automatically tried to push the plane of the nose down, then the flight crew tried to push the nose back up. But if the AOA signal is erroneous, the MCAS can cause an airplane to stall. A stick shaker is a device that gives a pilot warning of an imminent stall.

But if the sensors were not sending the correct data to the MCAS system, the software likely calculated that the aircraft was approaching stall conditions while it was well within normal flight conditions during takeoff, pushing the aircraft into a dive.

More evidence supporting the theory that faulty sensor data caused the crash of a Lion Air Boeing 737 MAX in October has emerged from the aircraft's flight data recorder. Unable to trust their readings, the pilots resorted to asking air traffic control what their speed and altitude were.

Its second last flight was from Denpasar in Bali to Jakarta.

Faulty system or faulty maintenance?

The flight crew - at an altitude of just 5000 feet - had very little time to resolve the issue before the plane crashed into the Java Sea at a reported 450 miles per hour.

It was unclear why the pilots on the failed flight from Jakarta to a regional airport the next day were unable to do the same, exactly what technicians did to try to fix the problems and if there were other steps that should have been taken given that four of the crashed aircraft's six previous flights had experienced technical problems.

"The flight from Denpasar to Jakarta experienced stick shaker activation during the takeoff rotation and remained active throughout the flight", the committee said.

But they can include immediate recommendations if they have pressing safety concerns.

After the crash, Lion Air instructed pilots to provide a "full comprehensive description" of technical defects to the engineering team, KNKT said.

"In our view. the plane was not airworthy", Utomo said. "Safety remains our top priority and is a core value for everyone at Boeing", a spokesperson said.

What happened on flight JT610? Boeing calls for the installation records, calibration of the new sensor, or clarity on its condition - "whether the sensor was new or refurbished". Discussions between the left and right pilots were about what?

"We still don't know yet, if it contributed or not", he said in response to a question.

Most air accidents are caused by a cocktail of factors and investigations typically take around a year to complete.

The pilots of Lion Air Flight 610 were engaged in a futile tug-of-war with the plane's automatic systems in the minutes before it plunged into the ocean, killing all 189 people on board.

The parents of one passenger is suing Boeing, alleging the 737 MAX 8 had an unsafe design.

Pramesti also said a new regulation was being planned to limit the risk of pilot fatigue occurring and should be issued in the "near future".

Lemme said he was troubled that there weren't easy checks to see if sensor information was correct, that the crew of the fatal flight apparently wasn't warned about the problems on previous flights and that the Lion Air jet wasn't fully repaired after those flights.

Recommended News

We are pleased to provide this opportunity to share information, experiences and observations about what's in the news.
Some of the comments may be reprinted elsewhere in the site or in the newspaper.
Thank you for taking the time to offer your thoughts.