Lion Air crash caused by computers

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Sounds like they tried their damnedest to save the aircraft.

But the ever fucking computers knew better.


Lion Air pilots fought to save airplane before fatal crash

https://nypost.com/2018/11/27/lion-air-pilots-fought-to-save-airplane-before-fatal-crash/

By Yaron Steinbuch November 27, 2018 | 3:35pm | Updated

The pilots of the doomed Lion Air airliner fought to save the plane almost from the moment it took off – as its nose was forced down apparently by an automatic system that received flawed sensor readings, according to a report.

The nose was forced down more than a dozen times during the 11-minute flight, but the pilots managed to pull it up repeatedly until they finally lost control of the Boeing 737 Max 8, which slammed into the Java Sea on Oct. 29, killing all 189 people aboard, The New York Times reported.

Information from the flight data recorder confirmed investigators’ theory that the maneuvering characteristics augmentation system, or MCAS, installed on Boeing’s newest 737 was to blame, the paper reported, citing a preliminary report from Indonesian authorities.

The MCAS, which is meant to prevent the nose from rising too sharply, causing the plane to stall, instead forced it down due to bad information sent from sensors along the fuselage, findings show.

“The pilots fought continuously until the end of the flight,” said Capt. Nurcahyo Utomo, chief of the air accident subcommittee of the Indonesian National Transportation Safety Committee, which is leading the probe.

R. John Hansman Jr., a professor of aeronautics and astronautics at the Massachusetts Institute of Technology, told The Times: “It’s all consistent with the hypothesis of this problem with the MCAS system.”

Earlier this month, Boeing and the Federal Aviation Administration issued a safety alert, saying a sensor issue could cause the 737 Max 8 to nose dive and crash because of incorrect input from the sensors of the “angle of attack,” the angle of the plane or its wings relative to wind.

After the crash, pilots have complained that they had not been fully informed about the MCAS — and how they would have to respond differently in case of the type of emergency that downed Flight 610.

Lion Air pilot reported 'speed and altimeter' problem hours before deadly crash

Boeing has said the proper procedures for responding to an incorrect MCAS activation were already explained in flight manuals, so there was no need to address this specific system in the new 737 Max 8.

In a statement Tuesday, the company said it could not discuss the crash while it remains under investigation but noted again that “the appropriate flight crew response to uncommanded trim, regardless of cause, is contained in existing procedures,” The Times reported.

Pilots also have pointed out a potentially critical difference between the system on the new 737s and the older models.

In the older versions, flight crews said they could help address the problem of the nose being forced down improperly — a situation known as “runaway stabilizer trim” — by pulling back on the yoke in front of them.

In the Max version, that measure does not work, pilots said, citing information they have received since the crash, according to the newspaper.

The pilots on Flight 610 apparently pulled back on their control columns forcefully to no avail, according to the information from the flight data recorder.

One of the angle-of-attack sensors on the fateful flight was replaced before the plane’s penultimate flight after having transmitted some incorrect angle and speed data, investigators have said.

Investigators have yet to recover the cockpit voice recorder, which could provide vital information about the pilots’ actions and whether they followed correct procedures to deal with the emergency.

The captain had handed the controls over to the first officer just before the plane plummeted on its flight from Jakarta to Pangkal Pinang.
 
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Insert Star Trek video clip about being unable to engage the manual overrides HERE
 
...The captain had handed the controls over to the first officer just before the plane plummeted on its flight from Jakarta to Pangkal Pinang...

Probably because the Captain was desperately flipping through the manual trying to figure out how to shut the damned thing off...
 
Probably because the Captain was desperately flipping through the manual trying to figure out how to shut the damned thing off...
Probably should have pulled the circuit breaker for it... Granted as airline pilots we are taught never to disengage the safeties unless the flow chart calls for it, but at that point, they didn't have much to lose by doing so and it could have been a last ditch effort.


Hopefully the plane is designed in such a way that if it suffers a power/command/control loss that it can still be flown stick-and-rudder. I realize most a/c are fly-by-wire these days, but there should still be a way to dead-stick the thing in without instrumentation or running systems.
 
Probably should have pulled the circuit breaker for it... Granted as airline pilots we are taught never to disengage the safeties unless the flow chart calls for it, but at that point, they didn't have much to lose by doing so and it could have been a last ditch effort.


Hopefully the plane is designed in such a way that if it suffers a power/command/control loss that it can still be flown stick-and-rudder. I realize most a/c are fly-by-wire these days, but there should still be a way to dead-stick the thing in without instrumentation or running systems.
Self driving cars won't have manual/physical backups.
 
Self driving cars can come to a halt within a matter of seconds when there is a problem.
Or they can go berserk and kill the occupant and many bystanders or the occupants of other cars.

There is no justification for a vehicle with no manual/physical controls.
 
Interesting report...

However, in the case of the B-737 MAX 8 and 9 there are reports that reversing the control column (pulling back) won’t work to stop the stabilizer trim from trimming nose-down in the scenario described in the AD. Others have discussed the rationale behind this design decision[5], but suffice to say that this would be different than what a pilot would be expecting based on previous experience on other Boeing 737 models. The erroneous AOA could trigger both an erroneous stall warning and a pitch down (due to the MCAS trimming the horizontal stabilizer).
...
The AD also implies that it is possible that the trim cutout switches (guarded switches that disconnect electrical power from the trim system) may not work, stating:
“If relaxing the column causes the trim to move, set stabilizer trim switches to CUTOUT. If runaway continues, hold the stabilizer trim wheel against rotation and trim the airplane manually.”
...
https://airlinesafety.blog/2018/11/19/the-aoa-problem-what-we-can-do-about-it/
 
Interesting report...

You can fly a 737 out of trim. The stick will be very heavy until you manually trim out the nose down trim in this scenario. The 737 also has a mechanical reversion mode (cables).

Nothing has changed. You can override the trim down by trimming up electrically. The MCAS will reengage after 5 seconds of releasing the trim, so to prevent that, the pilots need to move the STAB TRIM CUTOUT switches to CUTOUT. Then if they need to further trim, they can do it manually.

737-max-trim-control.jpg
 
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You can fly a 737 out of trim. The stick will be very heavy until you manually trim out the nose down trim in this scenario. The 737 also has a mechanical reversion mode (cables).

Yeah, your pics made this part easy to understand:

hold the stabilizer trim wheel against rotation and trim the airplane manually

I’m sure the major problem here was them not being able to figure out what the hell was going on. Apparently (obviously?) they never manually trimmed.
 
Yeah, your pics made this part easy to understand:



I’m sure the major problem here was them not being able to figure out what the hell was going on. Apparently (obviously?) they never manually trimmed.

That might be like a cashier these days that would need to calculate change.
 
The family of a man who was killed when a Lion Air flight crashed in October has sued Boeing Co, alleging the 737 MAX 8 aircraft was "unreasonably dangerous" and demanding a jury trial in Chicago, where the U.S. manufacturer is based.The lawsuit was filed on Monday in the Circuit Court of Cook County, Illinois, on behalf of the estate of Sudibyo Onggo Wardoyo, who died when Lion Air Flight 610 crashed into the Java Sea after taking off from Jakarta on Oct. 29.
All 189 people on board the plane were killed.
The lawsuit alleges that the two-month-old Boeing aircraft was unreasonably dangerous because its sensors provided inaccurate data to its flight control system, causing its anti-stall system to improperly engage.
It also alleges Boeing failed to provide adequate instructions to pilots on how to respond to and disengage the plane's anti-stall system.

More at: https://news.yahoo.com/lawsuit-against-boeing-over-lion-air-crash-demands-151352968--finance.html
 
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