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MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures

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MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures

Old 7th Jul 2019, 13:15
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Originally Posted by infrequentflyer789
(a) we don't actually know that the AOA vane itself was the issue on LionAir (or ET, although there is more evidence of a vane failure mode in that case)
(b) if you are troubleshooting a problem persisting over several flights (AOA issues did not start with the replaced sensor) do you assume the cause is the part you have replaced with new, or that the cause is more likely elsewhere?
Indeed the AOA issues didn't start after replacing it, there were some faults reported by the OMF system on two previous occasions, that's why they replaced it. But the stick shaker simptom started after they replaced it. And apparently the OMF system didn't report any more problems with the AOA after replacing it, the pilots didn't report any problems that would directly suggest AOA issues either, so the engineers didn't look into it further between the last two flights.

But the bigger problem with the theory that better reporting would help (I think) is that maintenance appear to have their own automation dependency problem. The Lion Air guys asked the aircraft (BITE/IFIM) what was broken, fixed that and asked the aircraft if everything was now OK, got a yes = job done, end of thinking.
Actually, no, they didn't stop after the aircraft said everything was OK. If they did that, they wouldn't have replaced the AOA vane. Instead they noted that the AOA issues were repetitive, and even as the self diagnosis systems said everything was fine, they replaced the vane because the maintenance manual required doing that in case of repetitive issues. You could claim they relied too much on their manuals, but I don't think that's necessarily a bad thing.

For a more detailed actual example of why reporting stick shaker would make sod-all difference to the outcome, consider this result of a busted AOA sensor:
[...]
Yes, reporting the stick shaker may not have saved the next Lion Air flight. But if there was, let's say, a 25% chance it could have saved it, wouldn't you say it would have been a good idea to report it? If you report the exact symptoms to your doctor they may still misdiagnose you. But why would you make the doctor's job harder by not telling him all the symptoms?

And, again, the actions taken by Lion Air after the accident confirm that the pilot reports could have been better. Otherwise one of their safety actions as a result of the accident wouldn't have been "instruct all pilots to fill the AFML report with as much details as deem necessary to provide a full comprehensive description of the technical defect to the engineering team. This measure should be applied with immediate effect."

Note that I suggest working out which incident that was before whining about inexperienced or third-world crews or airlines or maintenance...
Actually most of my whining so far has been about Boeing and the FAA, and I think most of the focus should be on them. In my opinion their initial actions, and especially their attitude after the accidents, were appalling. Fighting tooth and nail to prevent the grounding and trying to shift as much blame as possible on the foreign pilots and minimize their own contribution to the accidents was disgusting.

My initial post about not reporting the stick shaker was a reply to yoko1 that said, if I remember correctly, that the crew from the accident flights didn't do a good job, and that the Lion Air crew that saved the aircraft did a great job. In my reply I was pointing out that in fact all 3 crews did things that many posters, maybe including him, would consider questionable, and I provided examples.

What I was trying to convey was that what saved the previous Lion Air flight may not have been just good crew decisions, but also an element of luck. For example, what people may regard as a mistake, enabling the auto-pilot with the stick shaker active, actually bought them time and allowed them to gain altitude. The A/P remained enabled for about a minute. If they didn't enable it they would have experienced MCAS earlier and at a lower altitude, and they may have very well crashed that aircraft.

I agree that we focus too much on the pilot actions. It wasn't my intention to derail the thread with the discussion about the pilot reports, and in any case that seems to be a closed issue, the necessary actions seem to have been taken by Lion Air to improve the pilot reports.
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Old 7th Jul 2019, 13:25
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This is slightly off topic but... This is a lecture about the history of 737 creation, and it touches MAX slightly. Published on Nov 14, 2017 in a bit promotional tone, however, you can hear a lot about decision making process, design features selection ets.

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Old 7th Jul 2019, 14:54
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BBC News...

Flyadeal, the low-cost airline Saudi Arabian airline, has cancelled an order for 30 Boeing 737 Max aircraft

Hard times indeed...
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Old 7th Jul 2019, 14:56
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Now the European regulators are bringing up issues with the 737 Max's autopilot as well.
https://www.bloomberg.com/news/articles/2019-07-05/europe-sets-out-demands-for-boeing-before-max-can-fly-again

Boeing 737 Max's Autopilot Has Problem, European Regulators Find

Europe’s aviation regulator has outlined five major requirements it wants Boeing Co. to address before it will allow the planemaker’s 737 Max to return to service, according to a person familiar with the matter. One of them, about the jet’s autopilot function, hasn’t surfaced previously as an area of concer

The European Union Aviation Safety Agency has sent its list to both the U.S. Federal Aviation Administration and Boeing, the person said, asking not to be identified because the details aren’t yet public. The FAA hasn’t publicly discussed details about what changes it’s demanding on the Max, so it’s difficult to know whether the EASA demands differ dramatically -- and whether they would significantly boost the cost and time to get the Max back in the air.

Regulators worldwide grounded Boeing’s best-selling plane in March following two crashes in five months that killed a total of 346 people.

The issues being raised by EASA are consistent with the FAA’s own questions, said a person familiar with the U.S. agency’s work who wasn’t authorized to speak about the matter. In a statement, the FAA declined to confirm the specific matters being raised by EASA but said: “The FAA continues to work closely with other validating civil aviation authorities on our review of Boeing’s certification documentation for the 737 MAX. This process involves regular communications among all parties.”
Asked about the potential impact of EASA’s concerns, Boeing issued a statement saying company officials continue “to engage with regulators and are providing information as we work towards the safe return to service for the MAX.” Autopilot ConcernsEASA’s checklist includes a number of issues that have been disclosed: the potential difficulty pilots have in turning the jet’s manual trim wheel, the unreliability of the Max’s angle of attack sensors, inadequate training procedures, and a software issue flagged just last week by the FAA pertaining to a lagging microprocessor. But the agency also listed a previously unreported concern: the autopilot failing to disengage in certain emergencies.

“Any of these could significantly affect the return to service, but we don’t know if they are actually going to become requirements or are they just items for discussion,’’ said John Cox, a former 737 pilot who is president of the aviation consulting company Safety Operating Systems.

Cox said that such questions between regulators are the norm during aircraft certification work and may not pose new risks for Boeing.

The one issue Cox said he hadn’t previously heard about involved the autopilot. Having to alter a system as complex as the 737’s autopilot could have major ramifications, he said. However, he said he isn’t aware of any underlying safety issues with the autopilot that would justify such an action.

The European regulator has found that the autopilot doesn’t always properly disengage, which could mean that pilots wouldn’t have the time to intervene before the plane begins to stall.

The EASA list excludes several other smaller issues that the agency hasn’t flagged as critical. The agency’s findings follow its broad, independent review of the 737 family’s entire flight control system that focused on the differences between the Max variant and the older “Next Generation” model, the person said. EASA opted to conduct its own assessment of the aircraft.

The review has become a critical focal point for the industry in gauging when the plane will be able to fly again, with regulators globally expected to lean on EASA’s findings. The FAA is facing multiple investigations over its handling of the original certification of the Max and the so-called Manuevering Characteristics Augmentation System that has been linked to both crashes.
Boeing Reprograms 737 System Linked to CrashesA software update will prevent a single sensor from activating the Maneuvering Characteristics Augmentation System. The data from both sensors will be considered.

It’s not clear how difficult it will be for Boeing to address the issues described above. People familiar with the matter told Bloomberg last week that the latest software problem could take as long as three months to fix. The FAA has also previously denied that the trim wheel -- which is used to lift or lower a plane’s nose during an emergency -- would cause delays. Potentially more complex will be addressing the AOA, or angle of attack, sensors on which MCAS relies. At the time of the Ethiopian crash in March, Boeing’s system was using just one of the two sensors installed on the plane. EASA director Patrick Ky said in an interview last month that retrofitting additional hardware was not off the table, a measure that could be costly and time consuming for the manufacturer.

EASA, in its recommendations, stopped short of telling Boeing how to address the issues, instead asking the company to propose solutions that will then be assessed, the person said. For example, if Boeing can prove the effectiveness of a new training procedure that doesn’t include the more burdensome requirement for simulator training, it could avoid that additional expense.
Coordinating RelaunchBoth the FAA and EASA along with Canada and Brazil, have meanwhile come together in tentative agreement that the return to service should be closely coordinated in an effort to help restore public trust in the global aviation safety system, people familiar with the matter have said, though they cautioned that EASA may still make additional requests and lag behind the FAA.

A spokesman for EASA wasn’t immediately able to comment. FAA acting Administrator Daniel Elwell has said that the grounded plane won’t be returned to service until the agency can be assured it is safe and pilots are adequately trained to handle any emergencies.

Boeing has been telling customers and others in the industry that it expects the plane will be returned to service by September. That timetable includes fixing the software implicated in the two crashes as well as the latest flaw identified with the microprocessor, said a person familiar with the company’s guidance.
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Old 7th Jul 2019, 15:23
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Longtimer
https://www.bloomberg.com/news/articles/2019-07-05/europe-sets-out-demands-for-boeing-before-max-can-fly-again
The Bloomberg EASA article was posted 2 days ago, and extensively discussed in this thread.
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Old 7th Jul 2019, 16:17
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Originally Posted by wonkazoo

At the moment that the PF handed off control of LT610, MCAS was in the MIDDLE of an 11-second run......
Wonk,

I guess I should thank you for providing one of the best examples of what happens when you start with a pre-formed conclusion and try to shoehorn the evidence to fit. You have made a fundamental error in your attempt to interpret what these FDR traces are saying.

I am in the middle of a very hectic multi-day trip (yes, I do have a day job), so I don’t really have the time to break it down for you. I’m going to suggest that you dial back the emotion, put your earnestly held beliefs on the shelf, take a careful second look, and see what this data is really saying. I bet some other folks here are even willing to give you a hand. I’ll even give you a hint - that blue vertical line the Leeham News author put on the diagram isn’t saying what you think it is saying.

I’ll check back in when I get some time and see if you are anyone else came up with the right answer. Until then....

Sincerely yours,

Yoko
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Old 7th Jul 2019, 16:17
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https://www.seattletimes.com/opinion...h-flow-period/
What will it be, Boeing? Great airplanes that generate cash flow or great cash flow, period?

By Stan Sorscher
Special to The Times

Employees come to work to do their jobs. We aren’t usually aware of workplace culture, even over a span of years.

We learn culture from co-workers and managers when they make decisions and demonstrate problem-solving skills. Leadership messages affect thousands of decisions that add up to success or failure of the organization.

For many years, Boeing competed with Airbus and other producers for airline customers based on performance of its products. As a recent news report put it, Boeing now competes for investors with Exxon and Apple.

Boeing rose to the top of the airplane business as an engineering company, focused on performance of its products. Boeing made bold decisions that “bet the company” and prevailed over competitors.

In the ’90s, Boeing business culture turned to employee engagement, process improvement and productivity — adopting the “quality” business culture that made Japanese manufacturers formidable competitors.

In the late ’90s, Boeing’s business culture shifted again, putting cost-cutting and shareholder interests first.

Some business cultures are well-suited to commodity-like products but are a bad fit with performance-driven products.

Ask a financial analyst, “Are airplanes commodity-like or performance-driven?”

Business instinct is to cast the question as a market transaction. Airline customers worry about price, delivery dates, training costs, spares, maintenance and other factors, but, overall, those considerations come out very close in the end. The last major innovation in air travel was the jet engine in the 1950s. A business analyst would say the airplane business is “mature,” the products are standardized, innovation is slow, so airplanes are commodity-like.

Now ask a different question: “Are the design, development, testing and manufacture of airplanes commodity-like or performance-driven?” Whoa. Tough question.

Actually, making airplanes is performance-driven.

Success or failure of an airplane program turns on productivity. The first airplanes off the production line sell at a loss. Costs come down over time, the quicker the better. If your business model emphasizes productivity, employee engagement and process improvement, costs go down faster. This was the essence of the “quality” business model Boeing followed in the mid-’90s. The 777 had the best “learning curve” in the business.

On the other hand, if your industry is mature, and your products are commodity-like, business-school theory says a cost-cutting model is appropriate.

Wal-Mart perfected its particular version of the cost-cutting business model. Amazon adapted that model to its industry. Boeing has adapted it to high-end manufacturing. These companies are super-stakeholders with market power over their supply chains. The point of this business model is that the super-stakeholder extracts gains from the subordinate stakeholders for the short-term benefit of investors.

Subordinate stakeholders are made to feel precarious and at-risk. Each supplier should see other suppliers as rivals. Similarly, each work location should know it competes on cost with rival work locations. Each state or local government should compete for incentives against rival states.

In this model, subordinate stakeholders never say “no” to the super-stakeholder — not workers, not suppliers, not state legislatures.

This cost-cutting culture is the opposite of a culture built on productivity, innovation, safety, or quality. A high-performance work culture requires trust, coordination, strong problem-solving, open flow of information and commitment to the overall success of the program. In a high-performance culture, stakeholders may sacrifice for the good of the program, understanding that their interests are served in the long run.

In the productivity-based 777 program, it would have been career-limiting to withhold negative information from managers. They needed timely information to find a solution as far upstream as possible.

According to Boeing’s annual reports, in the last five years Boeing diverted 92% of operating cash flow to dividends and share buybacks to benefit investors. Since 1998, share buybacks have consumed $70 billion, adjusted for inflation. That could have financed several entire new airplane models, with money left over for handsome executive bonuses.

Boeing’s experience with its cost-cutting business culture is apparent. Production problems with the 787, 747-8 and now the 737 MAX have cost billions of dollars, put airline customers at risk, and tarnished decades of accumulated goodwill and brand loyalty.

Stakeholders throughout the industry want our trust restored. This is a leadership moment for Boeing executives and its board of directors. Will Boeing make great products, which generate cash flow, or will it continue being a company that generates great cash flow — and makes airplanes?

Stan Sorscher was a physicist at Boeing for 20 years and has been on staff at the Society of Professional Engineering Employees in Aerospace union since 2000.
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Old 7th Jul 2019, 16:42
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It seems (from figures that someone gave) that the hand-trim wheel takes an awful lot of turns to go not very far.
How much grunt does it take (unloaded) on other big jets?

On the MAX the wheel looks rather small and rather far forwards.
Did the designers actually try it under aerodynamic load?

[Yes, I read that bit about making the aircraft do the cha-cha to unload it momentarily]

Curious Mac
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Old 7th Jul 2019, 17:03
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I've posted this before, but it's very informative.

[Ed] 737 Max Crashes (was Shutdown caused Boeing crash.) - Page 4 - International Skeptics Forum

Post 143, quote.

"I agree it's a flawed design. And I used to work there. I'm glad I don't now.
Regarding the trim wheels: When the NG was being introduced, I happened to be the Lead Engineer in charge of them and a whole lot of other stuff. There were some issues. The new display system created a pinch point between the dash and the wheel. We had to make the wheel smaller. And the new trim motor resulted in the wheel, which is directly connected to the stabilizer by a long cable, springing back when electric trim was used. It was an undamped mass on the end of a spring. We had to add a damper.
Result: Depending on the flight conditions, the force to manually trim can be extremely high. We set up a test rig and a very fit female pilot could barely move it.
As I said, I'm glad I'm no longer there. "

Alchad
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Old 7th Jul 2019, 17:27
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Not sure what to think of this (WSJ) :

FAA, Worried About Leaks, Asks Boeing 737 MAX Panel to Sign Nondisclosure Agreements
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Old 7th Jul 2019, 17:55
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Originally Posted by Fly Aiprt
Article needs subscription, please copy/paste.
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Old 7th Jul 2019, 18:40
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Originally Posted by hans brinker
Article needs subscription, please copy/paste.
"FAA, Worried About Leaks, Asks Boeing 737 MAX Panel to Sign NondisclosureAgreements.


By Andy Pasztor
July 1, 2019 9:55 pm ET WSJ Pro



The nondisclosure agreements appear to reflect concerns by some FAA leaders about the premature release of technical details.

U.S. aviation regulators are taking precautions over concerns about details leaking from discussions about software fixes to grounded Boeing 737 MAX jets.

The Federal Aviation Administration has gotten representatives of more than half a dozen foreign air-safety regulators to sign nondisclosure agreements about such deliberations, according to an agency spokesman and another person familiar with the details. Initially, only individuals serving as staff to the international advisory committee were required to sign such agreements, the person said.

The committee, led by former National Transportation Safety Board Chairman Chris Hart and including Brazil, Canada, China and the European Union, met recently while those restrictions were pending. The group is conducting a comprehensive review of flight-control features on the MAX fleet, which the FAA hopes will enhance the global credibility of eventual fixes.

The group is expected to take more than three months to weigh in on the safety of proposed fixes to 737 MAX software, as well as review some underlying flight-control systems that have come into question as a result of two fatal MAX crashes in less than five months.

The nondisclosure agreements, at least in part, appear to reflect concerns by some FAA leaders about the premature release of technical details. The agency spokesman said the nondisclosure agreement pertains to Boeing proprietary information and unauthorized released of trade secrets and isn’t intended to cover panel results or recommendations.

The nondisclosure issue comes amid news reports highlighting differences of opinion among the countries and with U.S. regulators regarding additional simulator training for pilots. The FAA also has been sensitive about its efforts to persuade regulators from big aviation markets to agree to simultaneously lift the grounding of 737 MAX plans when the FAA takes such action.

China, which is participating in the panel, has balked at giving that assurance, according to U.S. government and industry officials."
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Old 7th Jul 2019, 18:45
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Hard to imagine that publishing reports or technical recommendations will not reveal any of Boeing's "trade secrets".
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Old 7th Jul 2019, 19:05
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Trade Secrets ? Really ??

Originally Posted by Fly Aiprt
"FAA, Worried About Leaks, Asks Boeing 737 MAX Panel to Sign NondisclosureAgreements.


By Andy Pasztor
July 1, 2019 9:55 pm ET WSJ Pro



The nondisclosure agreements appear to reflect concerns by some FAA leaders about the premature release of technical details.

U.S. aviation regulators are taking precautions over concerns about details leaking from discussions about software fixes to grounded Boeing 737 MAX jets.

The Federal Aviation Administration has gotten representatives of more than half a dozen foreign air-safety regulators to sign nondisclosure agreements about such deliberations, according to an agency spokesman and another person familiar with the details. Initially, only individuals serving as staff to the international advisory committee were required to sign such agreements, the person said.

The committee, led by former National Transportation Safety Board Chairman Chris Hart and including Brazil, Canada, China and the European Union, met recently while those restrictions were pending. The group is conducting a comprehensive review of flight-control features on the MAX fleet, which the FAA hopes will enhance the global credibility of eventual fixes.

The group is expected to take more than three months to weigh in on the safety of proposed fixes to 737 MAX software, as well as review some underlying flight-control systems that have come into question as a result of two fatal MAX crashes in less than five months.

The nondisclosure agreements, at least in part, appear to reflect concerns by some FAA leaders about the premature release of technical details. The agency spokesman said the nondisclosure agreement pertains to Boeing proprietary information and unauthorized released of trade secrets and isn’t intended to cover panel results or recommendations.

The nondisclosure issue comes amid news reports highlighting differences of opinion among the countries and with U.S. regulators regarding additional simulator training for pilots. The FAA also has been sensitive about its efforts to persuade regulators from big aviation markets to agree to simultaneously lift the grounding of 737 MAX plans when the FAA takes such action.

China, which is participating in the panel, has balked at giving that assurance, according to U.S. government and industry officials."
The biggest secret re Boeing is how much yourlead, Manager, Supervisor or fewlw employee makes!
The so called propietarry stuff is usually age related - Boeing and Airbus shar much more information than most realize, especially in models that are in service.

This is because, when safety is involved- an injury to one is an injury to all. That information sharing goes back decades..
Trade secrets
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Old 7th Jul 2019, 19:23
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Originally Posted by Fly Aiprt
"..... take more than three months to weigh in on the safety of proposed fixes to 737 MAX software, as well as review some underlying flight-control systems that have come into question as a result of two fatal MAX crashes ...
Anyone else read this as a probe into whether -- among other things -- the smaller manual trim wheel necessitated since the NG's panel reduced available space and the consequent significantly higher force requirements, will be under scrutiny?

Because, if so, there's a lot more than a couple of hundred Maxes at stake.

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Old 7th Jul 2019, 20:10
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Originally Posted by voyageur9
Anyone else read this as a probe into whether -- among other things -- the smaller manual trim wheel necessitated since the NG's panel reduced available space and the consequent significantly higher force requirements, will be under scrutiny?
Because, if so, there's a lot more than a couple of hundred Maxes at stake.
From the already discussed Bloomberg article https://www.bloomberg.com/news/artic...-can-fly-again
EASA’s checklist includes a number of issues that have been disclosed: the potential difficulty pilots have in turning the jet’s manual trim wheel,
the unreliability of the Max’s angle of attack sensors, inadequate training procedures, and a software issue flagged just last week by the FAA pertaining
to a lagging microprocessor. But the agency also listed a previously unreported concern: the autopilot failing to disengage in certain emergencies.


“Any of these could significantly affect the return to service, but we don’t know if they are actually going to become requirements or are they just items
for discussion,’’ said John Cox, a former 737 pilot who is president of the aviation consulting company Safety Operating Systems.


My emphasis, Peter
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Old 7th Jul 2019, 20:20
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There has been a fine debate between two posters about the handover of control from PIC to SIC on the Indonesian LT610 accident flight. One can deduce from the ATC transcript that the PIC handed over control about a minute or so before the crash. Unfortunately, I have not been able to find any statement about the exact time it happened.

The FDR traces in a chart shown to the Indonesian parliament show that a significant mechanical failure happened about 45 seconds before the crash. Post #1149 above includes a link to that chart.

Leeham News has drawn a vertical blue line down the chart at the 45-second mark. The forces on the left-side and right-side columns diverged at this time. Forces on the right-side column increased dramatically over those on the left-side. There may have been a breakout between the two columns, possibly due to the SIC now pulling back harder that the PIC had done. But, as Leeham News points out, that is not the only possible cause of the divergence. (Is it possible, I ask, that the horizontal tail surfaces were starting to do the unusual things they can do when the never-exceed speed is exceeded?)

In any event, the handover of control and the mechanical failure occurred at about the same time. But not necessarily at exactly the same time. In my opinion, not enough is known about the timing of the events to blame the mechanical failure on the transfer of control, or on some shortcoming of the SIC. It matters whether the handover happened a minute before or five seconds before.

YYZjim
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Old 7th Jul 2019, 20:50
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Originally Posted by YYZjim
There has been a fine debate between two posters about the handover of control from PIC to SIC on the Indonesian LT610 accident flight. One can deduce from the ATC transcript that the PIC handed over control about a minute or so before the crash. Unfortunately, I have not been able to find any statement about the exact time it happened.

The FDR traces in a chart shown to the Indonesian parliament show that a significant mechanical failure happened about 45 seconds before the crash. Post #1149 above includes a link to that chart.

Leeham News has drawn a vertical blue line down the chart at the 45-second mark. The forces on the left-side and right-side columns diverged at this time. Forces on the right-side column increased dramatically over those on the left-side. There may have been a breakout between the two columns, possibly due to the SIC now pulling back harder that the PIC had done. But, as Leeham News points out, that is not the only possible cause of the divergence. (Is it possible, I ask, that the horizontal tail surfaces were starting to do the unusual things they can do when the never-exceed speed is exceeded?)

In any event, the handover of control and the mechanical failure occurred at about the same time. But not necessarily at exactly the same time. In my opinion, not enough is known about the timing of the events to blame the mechanical failure on the transfer of control, or on some shortcoming of the SIC. It matters whether the handover happened a minute before or five seconds before.

YYZjim
What mechanical failure?
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Old 7th Jul 2019, 20:50
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Originally Posted by YYZjim

The FDR traces in a chart shown to the Indonesian parliament show that a significant mechanical failure happened about 45 seconds before the crash. Post #1149 above includes a link to that chart.


YYZjim
YYZjim, sorry, for the non Aviation experts, could you explain what in the chart indicates a mechanical failure?

thanks

Alchad
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Old 7th Jul 2019, 21:01
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Originally Posted by Fly Aiprt
[. . .] The agency spokesman said the nondisclosure agreement pertains to Boeing proprietary information and unauthorized released of trade secrets and isn’t intended to cover panel results or recommendations.
Boeing and the FAA shouldn't need to be told, at this point, that being seen to protect "trade secrets" that might be related to the investigation can only have an extremely negative impact on the world's opinions about B-produced aircraft and the corporate culture that produces them. Perhaps it's not clear to some high-level decision-makers how serious this situation has become.



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