Lion Air 737 Crashes Into Java Sea (Updated)

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Image: FlightRadar24.com

Image: FlightRadar24.com

A Lion Air Boeing 737 Max 8 crashed into the Java Sea just after taking off from Jakarta, in Indonesia, early Monday, and rescuers have begun to retrieve bodies from the site. No survivors have been found. The aircraft, with 189 people on board, departed at 6:21 a.m. en route to Pangkal Pinang island, about 400 miles north. The crew had told ATC they wanted to return to the airport when they were about 12 miles out, but they didn’t declare an emergency, according to CNN. A crew flying the airplane the night before also had reported problems, Lion Air's CEO Edward Sirait told local media, and the airplane was repaired and returned to service. It's not clear what the problem was or how it was addressed. FlightAware shows the aircraft climbed erratically to about 3,000 feet, then crashed into the sea 13 minutes after takeoff. Winds were calm and skies were mostly clear at the time of the crash. 

Controllers reportedly lost radio contact with the crew before the descent began. Officials told CNN rescuers found debris from the tail of the aircraft and they are using underwater drones to search the 100-foot-deep waters for the main fuselage. At least 300 rescuers have been deployed to the crash site. The Boeing Company released a brief statement on Monday saying the company is "deeply saddened by the loss of Lion Air Flight JT 610" and is providing technical assistance at the request and under the direction of government authorities investigating the accident. The accident is the first fatal crash for the 737 Max family.

Weather was clear and did not seem to be a factor. Investigators will likely be focusing on the aircraft performance to determine the cause of the crash, according to CNN aviation analyst Peter Goelz. The aircraft is powered by two CFM Leap engines, and was delivered to the airline in August. Lion Air was established in 1999 and is Indonesia’s largest budget airline. AVweb will update this story as more information becomes available.

Comments (3)

It is reported that the plane had a reverse trim problem and after looking at the data in FlightAware they were level doing about 400 knots and within seconds went into a dive at over 500 knots for what appears to be at a 70 degree angle, so based on this and this alone and until further details surface it would leave me with the impression that they experienced a runaway trim

Posted by: Allen Churchwell | October 30, 2018 7:39 AM    Report this comment

I agree: the known profile of that flight would incline one to suspect the HS trim system had moved the HS to the full nose-down position. While in theory "ANYTHING is possible," I have to doubt the cause of such an extreme nose-down trim situation (IF that is what happened...) would be a "runaway" HS.

Besides Boeing having incorporated so many protections against that actually happening, pilots are supposed to be sim trained in the "runaway stabilizer" procedures, should that ever become necessary.

I know of three other Boeing crashes that were the result of the HS being trimmed to the full nose-down position:

Flydubai Flight 981, (19 Mar 2016), Tatarstan Airlines Flight 363, (17 Nov 2013, & NWA B-720 (12 Feb 1963). In all three cases, that extreme HS nose-down trim was the result of the pilot deliberately trimming the HS that way, with his dual yoke-mounted HS trim switches.

Properly trained pilots would know that if you trim the Hor Stab to full nose down, that the plane will immediately go into a high speed dive, and unless there is a lot of altitude left, recovery will be impossible.

The elevators do not have enough remaining pitch control authority on their own, if the HS is trimmed to such an extreme nose down position. Thus, merely pulling back as hard as possible on the yoke, once the dive has commenced, will not pull the nose back up to any significant degree.

Additionally, the HS CANNOT be trimmed back to a level, or slightly nose up flight position, so long as the pilots are pulling back as hard as they can on the yoke. Such action will overload and stall the HS jack screws and they will not be able to trim the HS the other direction, until the pilots release their pressure on the yoke.

Well-trained pilots know this and would never have allowed an UN-recoverable trim situation to develop in the first place. Using extreme pitch trim is one of the most verboten actions of all.

Robert J. Boser
EditorASC

Posted by: Robert Boser | November 1, 2018 3:20 AM    Report this comment

I agree: the known profile of that flight would incline one to suspect the HS trim system had moved the HS to the full nose-down position. While in theory "ANYTHING is possible," I have to doubt the cause of such an extreme nose-down trim situation (IF that is what happened...) would be a "runaway" HS.

Besides Boeing having incorporated so many protections against that actually happening, pilots are supposed to be sim trained in the "runaway stabilizer" procedures, should that ever become necessary.

I know of three other Boeing crashes that were the result of the HS being trimmed to the full nose-down position:

Flydubai Flight 981; (19 Mar 2016); Tatarstan Airlines Flight 363, (17 Nov 2013; & NWA B-720 (12 Feb 1963). In all three cases, the extreme HS nose-down trim was the result of the pilot deliberately trimming the HS that way, with his dual yoke-mountain HS trim switches.

Properly trained pilots would know that if you trim the HS to full nose down, that the plane will immediately go into a high speed dive, and unless there is a lot of altitude left, recovery will be impossible.

The elevators do not have enough remaining pitch control authority on their own, if the HS is trimmed to such an extreme nose down position. Thus, merely pulling back as hard as possible on the yoke, once the dive has commenced, will not pull the nose back up to any significant degree.

Additionally, the HS CANNOT be trimmed back to a level, or slightly nose up flight position, so long as the pilots are pulling back as hard as they can on the yoke. Such action will overload and stall the HS jack screws and they will not be able to trim the HS the other direction, until the pilots release their pressure on the yoke.

Well-trained pilots know this and would never have allowed an UN-recoverable trim situation to develop in the first place. Using extreme pitch trim is one of the most verboten actions of all.

Robert J. Boser

Posted by: Robert Boser | November 1, 2018 3:28 AM    Report this comment

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