Fatal Lion Air flight crash.

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News is arriving that a Lion Air Flight with 189 people on board has crashed into the sea off Sumatra. The 737 plane is believed to be new and was delivered in August. The search for any survivors has started.

Original post

Terrible news. R.I.P. and condolences to the bereaved.

Hoping they get to the bottom of this very quickly since the wreckage is in shallow waters, the FDR and CVR should be able to provide a lot of information.

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Faulty AoA sensor alert

Boeing has issued a safety message to pilots on how to handle erroneous data from a key sensor on its 737 MAX aircraft in the wake of last week's deadly Lion Air crash in Indonesia.

The Chicago-based manufacturer said investigators probing the crash of Flight JT610, in which all 189 on board were killed, had found that one of the "angle of attack" sensors on the brand new plane had provided incorrect readings.

And from Boeing (http://boeing.mediaroom.com/news-releases-statements?item=130327)

Boeing is providing support and technical assistance to the Indonesian National Transportation Safety Committee and other government authorities responsible for the investigation into Lion Air flight 610.

The Indonesian National Transportation Safety Committee has indicated that Lion Air flight 610 experienced erroneous input from one of its AOA (Angle of Attack) sensors.

Whenever appropriate, Boeing, as part of its usual processes, issues bulletins or makes recommendations regarding the operation of its aircraft.

On November 6, 2018, Boeing issued an Operations Manual Bulletin (OMB) directing operators to existing flight crew procedures to address circumstances where there is erroneous input from an AOA sensor.

The investigation into Lion Air flight 610 is ongoing and Boeing continues to cooperate fully and provide technical assistance at the request and under the direction of government authorities investigating the accident.

NBC news.com

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Amazing news today (reuters): Lion Air crash scenario wasn't covered in Boeing 737 MAX manual, pilot unions say

Pilots of Boeing 737 MAX aircraft worldwide were not warned of a potentially dangerous feature suspected of playing a role in last month’s deadly Lion Air crash in Indonesia, investigators and pilots unions said.

Either I don't have the full picture, either I don't get it at all but stick pusher have been fielded on bombers and fighter jets since the early generation of jets (before finding their way in some airliners); most of them flown by 19 years old Joe's. Does those pilot union implies that the idea of counter acting the stick pusher in case of a false system alarm have to be taught in school for anyone to understand that? Are ppl landing on water when GPS are down? Have we seen anyone opening the side windows in flight because of a faulty speed indicator?

I don't get it.


Aircraft designers who install stick pushers recognize that there is the risk that a stick pusher may activate erroneously when not required to do so. The designer must make provision for the flight crew to deal with unwanted activation of a stick pusher. In some aircraft equipped with stick pushers, the stick pusher can be overpowered by the pilot. In other aircraft, the stick pusher system can be manually disabled by the pilot.

When a manual is not correctly printed (some of them are even subcontracted), Pilots (and the hundred of us in back cabin that do grant them for their professionalism) are gonna crash?

But let's go back on Lion's case:

Pilots could stop this automated response [(the stick pusher action)] by pressing two buttons if the system behaved unexpectedly, but questions have been raised about how well prepared they were for such an automatic reaction and how much time they had to respond.
Even though investigators say this problem was not covered in the operating manual, pilots did have access to a checklist designed to turn off errant systems when the plane started nosing downwards at the wrong time, said Soejono, a Lion Air instructor [...].

If this is another cultural thing like AF447, the proof is there that we have a systemic failure... in our pilot selection process.

(you can read here for more)

One day, if all that goes on, all plane's documentation will be amended like this:

*****************UNIVERSAL CHECK LIST ADD-ON PROCEDURE, YEAR 2057*************************

- open startup sequence checklist
- follow the procedure reading the list of actions line by line
- at the end paragraph before setting full automation with the appropriate described action, open cockpit door
- Yell for help (choose a sturdy and muscular passenger at your own convenience)
- With your PiC (Passenger in Charge) go to the cabin door, open it and make sure the PiC understand closing procedure
- go back in cockpit, press button firing-up full automation and wait for the bickering red light then turn back toward your selected passenger
- smile at him/her (or upon your preference repeat your company welcome sentence)
- Let him/her kick you out firmly of the plane
- During your flight time down the tarmac, please, invite him/her politely to not forget to close back the cabin door.

Enjoy your flight (the time it last).

The 727, which I fly, has a mechanical brake which engages if you pull or push the control column in the opposite direction to the movement of the trim wheel movement.

The 737 MAX I believe has an electrical brake. It is unclear how much force is needed to activate the brake. And apparently the stab trim will start running again a short while later unless the cutout switches are put in the cutout position. Recovery of the cockpit voice recorder is paramount to understanding what went wrong in the cockpit.

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Still no sign of the CVR to my knowledge


The most hyped features of the 737 MAX compared with its predecessor, the 737NG, are more fuel-efficient engines.

But as a result of the larger engines, which are placed higher and further forward of the wing, the jet’s balance changed. To address that, Boeing put in place more anti-stall protections, Leeham Co analyst Bjorn Fehrm said in an online post.

An automated protection system called the Maneuvering Characteristics Augmentation System (MCAS) kicks in when the angle of attack is too high, when the plane’s nose is too elevated, threatening a stall.


Pilots can stop the automated response by pressing two buttons if the system behaves unexpectedly, the FAA says.

That action is set out in a checklist used by Lion Air pilots for in-air troubleshooting, an instructor said. It is also required to be committed to memory by pilots.

Personally I do not see the stick pusher as a totally new feature on the MAX but Reuters and the Unions (3 to date) seems to say it is.


Suspecting that the false AoA indication triggered the stick pusher erratically it sounds then normal that the crew requested an RTB as soon as the problem was identified (plane unflyable with presumed chaos in cabin). We should then focus our attention on what was the decision process that led them to not pursue an immediate landing.

I am then very surprised that Unions and Experts does not raise this aspect of the story instead of targeting Boeing for something that does exist on one form or another since the 1950's...


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Is it possible that aeroplanes are getting way more complicated that they should. In other words...tired pilots no longer can master them ?

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Dispute arises among U.S. pilots on Boeing 737 MAX system linked to Lion Air crash

Airline pilot unions this week protested loudly that Boeing hadn’t provided them information during training about a new automatic flight-control system on the MAX that’s possibly linked to the crash of a deadly Lion Air crash in Indonesia.

But the United Airlines pilot leadership, in a sharp break with peers at the two other U.S. airlines flying the 737 MAX, pushed back against the criticism of Boeing.

The new system is designed to activate without pilot action in extreme flying conditions.

In an interview Thursday, Capt. Todd Insler, chairman of the United branch of ALPA, the Air Line Pilots Association union, broke ranks with his counterparts at American Airlines and Southwest Airlines who earlier this week publicly complained that this wasn’t disclosed to pilots during training or included in the 737 MAX pilot manuals.

the background without the pilot’s knowledge. He compared it to watching television: “I don’t need to know how it works.”

On Airbus jets, which unlike Boeing’s are designed to a philosophy that gives more autonomy to the automated flight-control systems and less to the pilots, there are dozens of systems that constantly work in the background without the pilot’s direct knowledge, he said.

Seattle Times.com

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And here we are, Lion Air statement confirms that:

The Lion Air pilots whose plane nosedived into the Java Sea in October, killing all those aboard, were battling multiple malfunctions almost as soon as the doomed flight began, according to a trove of new data released by Indonesian investigators.

They faced a cacophony of warnings that started seconds after takeoff and continued for the remaining 11 minutes before the crash.

The alerts included a so-called stick shaker -- a loud device that makes a thumping noise and vibrates the control column to warn pilots they’re in danger of losing lift on the wings -- and instruments that registered different readings for the captain and copilot, according to data presented to a panel of lawmakers in Jakarta Thursday.

The data also showed that in the final seconds, as they struggled to pull the Boeing Co. 737 Max 8 out of a dive that was being commanded by the plane’s flight computers, the pilots were pulling back on the control column with a force of as much as 100 pounds of pressure.

However, the data indicated that the plane was controllable -- the pilots had kept it under control for about 10 minutes before the final plunge -- and records from the previous flight of the same jet showed another set of pilots had an identical set of failures and landed safely.

So, once again,
- what the hell were they thinking to not bring back the plane immediately?
- How could they not read the checklist to disengage the MCA (they only needed to press two buttons)?
- What is this system that left un-monitored in the wild two pilots that reported facing serious difficulties when a simple reading at such trivial thing as the ADS-B data would have tell anyone inside Lion Air that something bad was happening - that help was needed?!

And last but not least, think at the chaos in the main cabin. Imagine the screams, the panic and the frightened passengers right after take-off devoid of any voices... now muted by meeting death on such a stupid occurrence. Engines were running fine, ctrls were properly actuating, weather was clement, plenty of fuel in the tanks, no fire, perfect navigation was possible... Is the service you pay airlines now solely reduced to be transported by ANY MEANS from point A to B*?



*Someone need to patent this brand for air transportation: S*** your ******* mouth Airways

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'Spend the minimum': How Lion Air hid equipment failures and beat regulators

However, an investigation by The New York Times claimed that Lion Air was so obsessed with growth that it failed to build a proper safety culture.

Government safety investigators told the TImes the company’s political ties allowed it to circumvent their recommendations and to play down instances that would cause alarm elsewhere.

Former employees told the paper the airline became adept at passing malfunctioning equipment from plane to plane rather than fixing problems.

Straits Times.com
Airline ratings.com

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Lion Air halts search for CVR

The Reuters report adds that Indonesia's National Transportation Safety Committee (NTSC) is likely to conduct its own search for the CVR, using ships from the country's navy "as soon as feasible". Negotiations with the navy are underway.


Although I fly an older generation plane, it is similar in many respects. In the event of a runaway trim, which is essentially what the doomed plane experienced, there are three actions which could be immediately performed. Now I'm not 100% sure if there is a stabilizer brake on the 737 MAX, but on the 727 there is, and it is engaged by moving the control column in the opposite direction to the runaway trim. This will immediately jam the trim and then the crew can disconnect the trim electrically thru the cutout switches, which apparently is what a previous crew on the same plane at Lion Air did. You can also simply grab the trim wheels and hold them. However, every crew member will have a different reaction to a surprise situation - the startle factor - , and if it has not been covered during training, the situation might well be mishandled. And as it turns out, if Boeing had rather chosen to make the MCAS system known to aircrew, this tragedy might not have happened.

The CVR information should shed a lot more light on what happened.

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Ananda, the search were halted by LionAir before being pursued by the Indonesia's National Transportation Safety Committee (NTSC). See my earlier post.
We will see how that unfold in the future but we surely can expect some interesting details to say the least.