Moon of Alabama Brecht quote
September 29, 2019

Boeing Failed To Consider Pilot Workload When It Designed and Tested The 737 MAX

The U.S. investigators of the 737 MAX incidents released their first recommendations for required changes on Boeing's best selling airplane. Their analysis of the accident causes confirms our earlier take.

A recent New York Times Magazine piece by one William Langewiesche blamed the pilots for the crash of two 737 MAX airplanes. We strongly criticized that Boeing friendly propaganda piece:

The author's "blame the pilots" attitude is well expressed in this paragraph:

Critics have since loudly blamed it for the difficulty in countering the MCAS when the system receives false indications of a stall. But the truth is that the MCAS is easy to counter — just flip the famous switches to kill it. Furthermore, when you have a maintenance log that shows the replacement of an angle-of-attack sensor two days before and then you have an associated stick shaker rattling away while the other stick shaker remains quiet, you do not need an idiot light to tell you what is going on. At any rate, the recognition of an angle-of-attack disagreement — however pilots do or do not come to it — has no bearing on this accident, so we will move on.

An AoA sensor failure and a following MCAS incident will cause all of the following: an unexpected autopilot disconnect, an airspeed warning, an altitude disagree warning, a stall warning and, after MCAS intervenes, also an over-speed warning. The control column rattles, a loud clacker goes off, several lights blink or go red, several flight instruments suddenly show crazy values. All this in a critical flight phase immediately after the start when the workload is already high.

It is this multitude of warnings, which each can have multiple causes, that startle a pilot and make it impossible to diagnose and correct within the 10 seconds that MCAS runs. To claim that "MCAS is easy to counter" is a gross misjudgment of a pilot's workload in such a critical situation.

After that piece was published Langewiesche went on CNBC where he repeated his slanderous allegations:

"It amounted to just a runaway trim"
"There was never a reason to ground [the MAX]"
"[Boeing's] largest mistake was to overestimate the quality of the pilots it was selling its airplane to"

Last week the National Transport Safety Board (NTSB) released 13 pages long recommendation (pdf) resulting from its investigation into the 737 MAX incidents. It strongly supports our view and counters Langewiesche's claims:

[T]he MCAS becomes active when the airplane’s AOA exceeds a certain threshold. Thus, these erroneous AOA sensor inputs resulted in the MCAS activating on the accident flights and providing the automatic AND stabilizer trim inputs. The erroneous high AOA sensor input that caused the MCAS activation also caused several other alerts and indications for the flight crews. The stick shaker activated on both accident flights and the previous Lion Air flight. In addition, IAS DISAGREE and ALT DISAGREE alerts occurred on all three flights. Also, the Ethiopian Airlines flight crew received Master Caution alert. Further, after the flaps were fully retracted, the unintended AND stabilizer inputs required the pilots to apply additional force to the columns to maintain the airplane’s climb attitude.

Multiple alerts and indications can increase pilots’ workload, and the combination of the alerts and indications did not trigger the accident pilots to immediately perform the runaway stabilizer procedure during the initial automatic AND stabilizer trim input.

The pilots did no do wrong. There were multiple alarms that required their attention. Boeing's assumptions that the pilots would immediately recognize a runaway stabilizer and react appropriately turned out to be wrong:

Although the NTSB’s work in this area is ongoing, based on preliminary information, we are concerned that the accident pilot responses to the unintended MCAS operation were not consistent with the underlying assumptions about pilot recognition and response that Boeing used, based on FAA guidance, for flight control system functional hazard assessments, including for MCAS, as part of the 737 MAX design.

It wasn't the pilots who failed. The system was designed in a way that made it extremely difficult if not impossible for the pilots to handle it in the available time.

Boeing never analyzed or tested the complete chain of events that would follow from a failure of an Angle of Attack sensor. Boeing tested an MCAS failure but only as an isolated incident, not as it would happen in real life:

To perform these simulator tests, Boeing induced a stabilizer trim input that would simulate the stabilizer moving at a rate and duration consistent with the MCAS function. Using this method to induce the hazard resulted in the following: motion of the stabilizer trim wheel, increased column forces, and indication that the airplane was moving nose down. Boeing indicated to the NTSB that this evaluation was focused on the pilot response to uncommanded MCAS operation, regardless of underlying cause. Thus, the specific failure modes that could lead to uncommanded MCAS activation (such as an erroneous high AOA input to the MCAS) were not simulated as part of these functional hazard assessment validation tests. As a result, additional flight deck effects (such as IAS DISAGREE and ALT DISAGREE alerts and stick shaker activation) resulting from the same underlying failure (for example, erroneous AOA) were not simulated and were not in the stabilizer trim safety assessment report reviewed by the NTSB.

An AoA failure triggers a number of alerts and the pilots need time to sort those out. An MCAS failure does not leave time to sort out anything. The pilots must react immediately. But they can not do so when multiple other alarms caused by the AoA failure also demand their attention.

Boeing built the MAX as the fourth generation of a plane that was designed in the 1960s. In each generation new systems and alarms were added and certified. But each added system was only tested in isolation. New fault tree analysis for the plane as a whole was not required as the original certification of the first 737 was still accepted as a base. No simulator tests were done that tested the ability of pilots to cope with multiple alarms that happen when a defect causes multiple interdependent systems or instruments to fail. Had Boeing made realistic assumptions about a pilot's reaction time to multiple alarms MCAS would have had to be implemented differently.

The NTSB recommends that Boeing and other manufacturers make new system safety assessments that consider the effects of all possible flight deck alarms and indications on the pilots reaction time when they respond to the failure of flight control systems. It asks for design changes of the alarm systems and for additional training. The NTSB recommends that the Federal Aviation Administration and other regulators include those demands into their general rules for aircraft certification.

The NTSB recommendations will likely induce the FAA to require additional changes on the currently grounded 737 MAX. They also seem to to push the FAA to require additional pilot training.

The NTSB report is bad news for Boeing. Most competing airplanes are much newer than the 737 and have multiple electronic sensors that can be easily combined to sort through and prioritize alarms. The 737 MAX is still largely based on the old mechanical and electrical systems of its predecessors. That makes it difficult to add a system that coordinates and prioritizes the cascade of alarms that can happen during certain events. The required changes will come on top of other changes that international regulators have loudly demanded.

It will likely take several more months until the 737 MAX is again certified and can go back into the air. Boeing still produces 42 MAX per month. It will now likely have to stop the production line until sound solutions for all the open questions are ready to be implemented.

---
Previous Moon of Alabama posts on Boeing 737 MAX issues:

Posted by b on September 29, 2019 at 14:01 UTC | Permalink

Comments

The pilot who wrote that Times article might want to stay out of any bars frequented by airline pilots for quite a while.

Great post and spot on analysis by the barkeep here.

Posted by: morongobill | Sep 29 2019 14:14 utc | 1

can anybody confirm, that the MCAS worked flip-flop like on only one of the AoA-sensors and change then to the other in next flight?

Posted by: peter.n | Sep 29 2019 14:37 utc | 2

Unexpected cracking found on critical Boeing 737 Next Generation part

https://komonews.com/news/local/exclusive-unexpected-cracking-found-on-critical-boeing-737ng-equipment

Posted by: Paul | Sep 29 2019 15:10 utc | 3

B has done it again.. exposed corporate propaganda and governmental indifference for the concern of life and safety of the governed. In the case of the design of a vehicle, as far as the designer is concerned, regulations are the only target (who cares if it unsafe, it meets regulation <= but the regulations themselves are actually there, not to protect the customer, instead to block legal liability to an injured customer for failure), and interpreting the regulation as a a most favorable outcome negotiated between industry/ corporate with so-called government regulators. Rarely does congress call to pre law making fact finding sessions the governed, you know the little people. Nearly always its that lobbyist who represents the feudal corporations who Congress calls to testify (usually not really to defend anything, but merely to put into the record what is needed for the government to find ways to help that particular feudal client to advance an opportunity).

The USA has become a corporate Kingdom, it has separated its governance from the governed Americans. Unlike the American back yard developer who has always been concerned about the safety and well being of their fellow Americans (that concern is a basic part of being an American), the USA is concerned that its profit centered monopoly powered private corporations (feudal lords) become heir to massive feudal corporate estates. the USA has even given them proxy power to tax governed Americans when one of their big monopolies feudal lords fail.

The USA siphons the pockets of those it governs and gives it bounty to their big boy corporations so the big boy corporations have exclusive rights to all of the business and to all of the wealth the business brings, everyone else either works for the feudal lord corporations, or starves to death. There should be 20 or 30 aircraft manufacturing corporations in America, competing with each other, not one or alternatively, which is my rather, the government (military) itself should design, and build all aircraft, cars, trucks and boats and license them to private interest.

Economic space competition no longer exist in America. The big boy corporations and their university system researchers get big time government contracts and support. The USA, since 1948-54 time frame, has increasingly been guilty of writing its regulations, and making its laws, favor the profit greedy monopoly powered private corporations, 5g is a perfect example (the USA serves the feudal lords and the monopoly powered feudal lord corporations control the USA). How did this happen?

Capitalism to be successful requires that the government referee the economic space to be sure no monopoly of any type creeps in (competition is the true essence of capitalism and that essence places capital always at risk). But when government no longer referees the economic space, no longer balances the share of profit between labor and capital (as in the current struggle between Auto workers and the Auto industry or worse, when the government becomes the creator (by laws it writes) and the protector(via its courts and international trade agreements) of, enforcer of monopoly powers within the economic space, capitalism descends into Economic Zionism. EZ is characterized by government creation of monopoly powers (which it bestows to a few feudal lords), the courts enforce the monopoly powers, and the agencies of government make sure the feudal lords own, control and dominate the economic space. I call this pathology: Economic Zionism.

Posted by: snake | Sep 29 2019 15:57 utc | 4

Thanks for the continued coverage of the results of Boeing financialization b

I recently visited family and my brother-in-law insists that the 737 Max crashes were pilot error and that interchange between us reminded me why I don't interact with my family much anymore

I read that snake the racist is spouting his Zionism garbage again on this thread. As I have asked snake repeatedly, where is the proof that the cult that own global private finance are all Jews? If you can't prove such then you are just spouting racist BS and should be banned from trolling such garbage at MoA, IMO

Posted by: psychohistorian | Sep 29 2019 16:38 utc | 5

Is the NTAB just blathering?

Per NTSB hi-lited in article above:

[1] "...the specific failure modes ...(such as an erroneous high AOA input to the MCAS) were not simulated as part of these functional hazard assessment validation tests."

Huh? The condition of a false AOA input signal was never considered in the simulations of MCAS failure "as part of these [737MAX] validation tests". !

I.e., AOA signal in simulations was working correctly, not failing, showing both the correct nose Attitude and nose motion. There was no simulation of failed AOA.

The NTSB statement seems a dodge. Just blathering.

Posted by: chu teh | Sep 29 2019 16:52 utc | 6

From NYT list of articles matching "Boeing"
BUSINESS
Boeing Underestimated Cockpit Chaos on 737 Max, N.T.S.B. Says
The federal agency, after a monthslong review, said the company had failed to account for how a misfire of an automated system could lead to other problems for pilots.
By Natalie Kitroeff

PRINT EDITIONBoeing Miscalculated Pilot Reaction, Report Says|September 27, 2019, Page B1
Sept. 26
-------
Quote: In conversations with airlines and aviation unions following the crashes, Boeing executives said that the accidents could have been avoided if pilots had simply run a standard emergency procedure. But officials with the safety board suggested that Boeing was too confident the average pilot could easily recover the plane in that situation, because the company had not considered the chaos that ensued inside the cockpit.

Dennis Tajer, the spokesman for the American Airlines pilots union, agreed with the investigators.

“They completely discounted the human factor component, the startle effect, the tsunami of alerts in a system that we had no knowledge of that was powerful, relentless and terrifying in the end,” Mr. Tajer said of Boeing.
---------
Thus NYT published articles for "two sides", not as bad as b says.

Posted by: Piotr Berman | Sep 29 2019 16:57 utc | 7

@peter.n - can anybody confirm, that the MCAS worked flip-flop like on only one of the AoA-sensors and change then to the other in next flight?

That is correct. MCAS runs on the active flight control computer. Each FCC only uses the value of one AOA vane. The FCC's flip their duty each time the aircraft is shutdown.

Posted by: b | Sep 29 2019 17:13 utc | 8

@Piotr Thus NYT published articles for "two sides", not as bad as b says.

A 14,000 word NYT Magazine cover piece with heavy attention from other media has much more impact than an 600 word piece on B1.

Posted by: b | Sep 29 2019 17:16 utc | 9

psychohistorian - We may loathe and detest expressed racism, anti-Jewish attitudes, homophobia, Irano-Russo-Sino phobia et al and be offended by their expression, but *if* we believe in freedom, of expression of speech then we have to accept offense, recognizing in our own turn that some of our own views are deeply offensive to others.

As my late husband used to impress on his students at university and high school levels, he would listen to (and read in their essays) their positions, views, outlooks but they had to support their arguments with really existing evidence, as he would his. Some of those views offended him, but he recognized the right of others to not only hold them but to be able to express them.

And if only from a selfish pov: we need to beware - the banning of the free expression of beliefs that one finds offensive will come back to bite us, who think we are righteous in *our* beliefs, opinions, ideas, worldviews.

Posted by: AnneR | Sep 29 2019 17:57 utc | 10

I read that snake the racist is spouting his Zionism garbage again on this thread. As I have asked snake repeatedly, where is the proof that the cult that own global private finance are all Jews? If you can't prove such then you are just spouting racist BS and should be banned from trolling such garbage at MoA, IMO Posted by: psychohistorian @ 5

I am afraid: psychohistorian @ 5 you have picked on the wrong person to suggest racism of. .. If the "Economic Space" anywhere is all Jewish or even mostly Jewish, or white or black or green or purple, or Indian or Russian, or whatever I would be surprised but then you can tell me, is it?

Since I don't know and don't care, now if you had said all monopolist, or all bankers , or corporate chieftains or something I might agree. Zionism (is a banker and corporate backed movement which began in Basil Switzerland in 1897).. ended up participating in the removal of the Ottomans from control of their oil rich land. That organization was involved in two world wars, was a part of the weaponization of immigration, and a part of the effort to destroy Germany in events that destroyed most of Europe (twice) at least that is my understanding from History, please correct my errors.

In USA governed America at least, their are more Christians who support religious Zionism (something to do with Israel) than people of the Jewish race as far as i can tell (you might get a copy of Christian Zionism, The tragedy and the Turning point: the Cause of our conflicts which is a DVD www.WHIT.org). It is indisputable that Zionism is a movement which started in Switzerland, its object was to take the oil from the Ottoman, but its facade took on several fronts, (some of which were purely racist in and of themselves, I think?)? It evolved to be a partner with many nations and organizations in a world wide effort to do just that. When highly competitive economic space is converted into highly access-limited monopoly-controlled economic space, previous government regulated economic space (capitalism) ozzes into a closed, access limited no competition allowed society where only a few wealthy persons and their corporations control everything including the governments that are suppose to keep economic space highly competitive, monopoly free. I have long termed that condition to be "Economic Zionism".
Sorry if that offends you..but I guarantee you, no racism was or is intended as i am 100% against racism..

I am truly amazed at your suggestion that I am either a racist or against Jews or any other race, nothing I have said should suggest that.. because neither is even close to the truth. Many of the doctor, lawyers, and Indian chiefs I meet seem to be Jewish, many of them, I think of, as my friends and I think they too would be surprised to hear your charge of racism. Zionism has nothing to do with race, its about oil, ownership, control, monopoly power, privatization and exclusive to a few, take no prisoner, allow no competition economics. Economic Zionism is descriptive name, that I long ago adopted, to describe an economic space where capitalism has gone bad.. it describes monopoly powers enabled, maintained and defended by government or controlled governments within an economic space. It takes its place in meaning along side well known economic concepts such as Capitalism, Fascism, Communism, Nazism, or Socialism or whatever.

Posted by: snake | Sep 29 2019 18:55 utc | 11

@ snake who wrote
"
Economic Zionism is descriptive name, that I long ago adopted, to describe an economic space where capitalism has gone bad.. it describes monopoly powers enabled, maintained and defended by government or controlled governments within an economic space. It takes its place in meaning along side well known economic concepts such as Capitalism, Fascism, Communism, Nazism, or Socialism or whatever.
"
The use of the word Zionism is attachable to the Jewish folk whereas Capitalism, Fascism, Communism, Nazism, or Socialism are not attached to any group of people directly. You FAIL once again to defend your racist concept. Prove to MoA readers that Jews are the cult of ownership of global private finance or stop using such racist garbage.

Posted by: psychohistorian | Sep 29 2019 19:43 utc | 12

@b - The FCC's flip their duty each time the aircraft is shutdown.

I think, boeing have considered a failure procedure, but if two AoA-sensors are
at odds, this should be noted to the pilots, but it would uncover MCAS.
and the probability for this case is higher then relying on only one sensor.

and a third AoA-sensor with some extra programming was too expansive for project controllers.

cheapest way though, was only one AoA-sensor in duty, but this was not an engeneerers' decision and it is quiet possible, to dig up such written document
and throw it in the face of the board.

Posted by: peter.n | Sep 29 2019 20:56 utc | 13

As b expertly points out, the 737 Max is the natural outcome of cost cutting in a corporate state that has deregulated safety. Even more dangerous is the restart of the Cold War with Russia to prevent a multi-polar world. This is failing but has escalated to include China and Iran. No better example the terminal condition is the House of Saud that spent hundreds of billions of dollars on American weapons but cannot defend itself. Donald Trump’s and Boris Johnson’s governments are also symptoms of the final throes of the Empire.

Posted by: VietnamVet | Sep 29 2019 22:17 utc | 14

The real question is does Boeing even have a plan "B", i.e. an FCC/MCAS redesign? So far all I've seen is their attempt to paper this over with documentation.

Posted by: EEngineer | Sep 29 2019 22:19 utc | 15

A 14,000 word NYT Magazine cover piece with heavy attention from other media has much more impact than an 600 word piece on B1.

Posted by: b | Sep 29 2019 17:16 utc | 9

Actually, I regularly read Business section and I rarely read Magazine on purpose. As I read online, I do not click "Magazine", but a story from Magazine can be interesting anyway. My theory is that news oriented to business audience persistently have a better information/propaganda ratio. Something about investors being keen to know what actually happens, I guess.

Posted by: Piotr Berman | Sep 29 2019 23:40 utc | 16

Below is a link to a Reuters article that originated at the WSJ

Boeing omitted safeguards on 737 MAX that were used on military jet: WSJ

The take away quote
"
(Reuters) - Boeing Co (BA.N) engineers working on the 737 MAX passenger plane’s flight-control system omitted safeguards included in an earlier version of the system used on a military tanker jet, The Wall Street Journal reported on Sunday, citing people familiar with the matter.

The engineers who created the Maneuvering Characteristics Augmentation System (MCAS) flight-control system more than a decade ago for the military refueling plane designed the system to rely on inputs from multiple sensors and with limited power to move aircraft's nose, the Journal said on.wsj.com/2mOypqT.
"

So here you have a system that was lowballed for commercial use because profit. I still don't see how Boeing can survive this debacle but they may be TBTF like the private banking system so then more losses will be socialized while the profits continue to be privatized

Posted by: psychohistorian | Sep 30 2019 0:05 utc | 17

And if only from a selfish pov: we need to beware - the banning of the free expression of beliefs that one finds offensive will come back to bite us, who think we are righteous in *our* beliefs, opinions, ideas, worldviews.

Posted by: AnneR | Sep 29 2019 17:57 utc | 10

Banning is perhaps too much, not for me to say. However, the post that irritated psychohistorian is indeed unworthy. Maximizing profits or "quasi-profits" is by no means unique to this historical period or restricted to any ideology or religion, except that in modern types we have this misguided "deregulation" and other (anti-)regulation paradigms that corrode public welfare. While there is some overlap between Zionists and champions of that pro-corporate creed, one cannot honestly support this as a determining feature.

What snake proposed is to use term Economic Zionism with no other justification that it would describe economic policy/ideology that he does not like. I guess it would be more justified to use term Zionist Operating System for operating systems that have to be patched every week in a futile quest to reduce their hackability. [According to Zionists, we should be thankful to Israel for the ability of using modern computer chips and other advances, so perhaps it is fair to blame Israel when computers or cell phones do not work to our satisfaction.] Thus cramped airplane seats would be Zionists seats and so on. How silly one can get? I mean, in good (not so good) old days, antiSemites often made more sense.

Posted by: Piotr Berman | Sep 30 2019 0:08 utc | 18

The real question is does Boeing even have a plan "B", i.e. an FCC/MCAS redesign? So far all I've seen is their attempt to paper this over with documentation.
Posted by: EEngineer | Sep 29 2019 22:19 utc | 15

The true plan should be to design a new plane fitting this market niche -- in terms of capacity and range. But according to Wikipedia, Boeing plans to have such a plane in 2030. Basically, they gave up on this segment of the market but want to milk the old cow as long as they can, squeezing it to the max (hence, -MAX model). That could be wise in some sense because this segment will face competition from Russians, Chinese and Brazilians, so in the future the profit margins will be thin. Compare to the decision of American car companies to abandon manufacturing sedan cars.

I do not understand well why financial markets reward such strategy with high P/E ratios, but from what I have read, Boeing focuses on the larger planes and apparently, they do decent job there.

Posted by: Piotr Berman | Sep 30 2019 0:24 utc | 19

Peter N @ 2:

I cannot confirm but my understanding is that on the Boeing 737MAX jets, there are two AoA sensors on the cockpit, one on each side, and the MCAS is linked to just one of these sensors. If the MCAS-linked sensor feeds the MCAS incorrect information, then the MCAS acts on it when the plane is under manual control. The Ethiopian Airlines flight crew apparently were not aware that the plane they were flying had the MCAS at all.

From what I recall reading about the Lion Air jet that crashed last year, the plane had flown from Bali to Jakarta and had had problems with a faulty AoA sensor. The sensor was repaired by engineers and the plane was made ready for its next flight (which turned out to be its last). The faulty sensor was linked to the plane's MCAS. So it appears the MCAS does not change from one sensor to the next on subsequent flights.

Here is the Lion Air jet's flight history.

Incidentally the norm for Airbus jets is to have three AoA sensors with two in the front and one in the tail fin.

Posted by: Jen | Sep 30 2019 0:31 utc | 20

psychohistorian | Sep 30 2019 0:05 utc

The principles of design of reliable control system that tolerate failure of one or more components are known for decades. Initially I was totally baffled how Boeing could make something so idiotic. From the discussions here and links, it seems that a non-idiotic solution was flatly not possible on existing computing hardware of Boeing 737, and design + attesting new hardware was deemed to take to long time. Basically, every input device would need to submit "messages" to the control hardware, reading and processing messages would require so-called interrupt for each message, and if there are too many interrupts, the control hardware is running out of time to compute necessary outputs in "real time", i.e. each of these results has a hard deadline.

Military planes have different standards for "non-obsolescence" and reliability. After all, USA military cannot hope that "competitors" will not catch up, or that in the worst case they can abandon a market segment (although, actually, it would be an excellent idea, focus on wrecking havoc in Latin America that produces desired results with satisfying frequency and abandon Middle East where nobody likes them, even in Latin America what works is bribery, economic sabotage etc., and if that does not work, USA can always wait, no real need for "cutting edge" airforce). When a plane malfunctions because of some component being incompletely tested, the crew ejects, or, at times, perishes, but those are pilots who understand the risks, and not the traveling public. In any case, military planes with MACS had sufficiently capable processors, and Boeing 737 does not.

New avionics seems to require a few years of testing before it is ready for passenger planes. That partly explains why Russians can catch up with military planes more readily than with passenger planes.

Posted by: Piotr Berman | Sep 30 2019 1:05 utc | 21

Common type rating is out of control. After two or three iterations, manufacturers should be forced back to the drafting table. No more layer after layer of new software on a 50 year old system. If Southwest wants to fly 737s, they should have to be satisfied with the old models instead of causing Boeing to cram an enormous engine in front of the wing on a new model. This system is crazy and jury-rigged and it kills people.

Posted by: Darius | Sep 30 2019 4:53 utc | 22

@psychohistorian #17, thank you for your comment.

Here is a link to some other comments about the B737 issues https://news.ycombinator.com/item?id=21107091 and from there you'll find one more link to the archived link from the wsj from behind the paywall, which is http://archive.is/h5ejA

Great information here, thanks all.

Posted by: Bob | Sep 30 2019 8:17 utc | 23

It is particularly disingenuous of the Boeing propaganda piece, and Boeings own assertions, to take the position that a MACS failure would be simple to rectify, and indeed would be the very first thing pilots would assume to be the base problem when suddenly assaulted by a huge array of warnings, when Boeing's whole strategy from the get-go was to make every attempt to keep the MACS system a secret from pilots! Even removing references from flight manuals! Infuriating that some pompous ass would have the audacity to blame the dead.

Posted by: J Swift | Sep 30 2019 8:58 utc | 24

Meant MCAS, obviously.

Posted by: J Swift | Sep 30 2019 9:08 utc | 25

Boeing Co engineers working on the 737 MAX passenger plane’s flight-control system omitted safeguards included in an earlier version of the system used on a military tanker jet, The Wall Street Journal reported on Sunday.
Posted by: psychohistorian | Sep 30 2019 0:05 utc | 17

The tanker was based on the 767 not the 737 which might have larger control surfaces on the tail, and the reason for using MCAS was because of pods for refueling rather than the oversized and mal-positioned engines, and might also have more capable CPU's for the flight controllers, so the technical conditions are quite different; nevertheless in important (non-technical) respects the most important difference between the two is that for the tanker the primary aim was to maximise safety and minimise dangers, while for the passenger aircraft the primary aim was to covertly manipulate the plane to bypass safety regulations and get approval under the old (obsolete) certification - irrespective of dangers - and get it on the market prematurely.

Litigators will have a field day from that one!

Posted by: BM | Sep 30 2019 15:54 utc | 26

As regards pilot workload and human error resulting in catastrophic failures, I can recommend a book published in 1982 on absent-minded lapses of performance:

Absent Minded?: Psychology of Mental Lapses and Everyday Errors
by James Reason and Klara Mycielska, 1 Nov 1982

It is primarily an academic book, but it is also written in an everyday style and is a joy to read. As well as dealing with more everyday lapses of mental performance, it gives very illuminating analysis of how mental performance can be degraded by fatigue, stress, poorly designed man-machine interfaces and unexpected environmental situations, and gives detailed analysis of several catastrophic failures in which hundreds of lives were lost, ranging from several catastrophic passenger aircraft crashes through shipping accidents to the Charge of the Light Brigade.

Although the two 737MAX crashes were not due to pilot error, it is relevant to the question of pilot overload in the 737MAX during MCAS failure, and the inadequacy of Boeing design procedures for this aircraft, particularly since - even if a pilot has full knowledge and understanding of MCAS and specific training to deal with its failure - he has to recognise the problem and respond within an impossibly short 10 seconds, while dealing with sudden information overload.

Posted by: BM | Sep 30 2019 16:25 utc | 27

Below is a link to Xinhuanet about Boeing pretending to care

Boeing creates new unit to improve product, services safety after 737 MAX crashes

I am jaded about Boeing's attempts to cover its ass after the fact. In a just world the Boeing leadership would be in jail and facing the death penalty.

Posted by: psychohistorian | Oct 1 2019 2:49 utc | 28

Long Seattle Times piece:

Boeing whistleblower’s complaint says 737 MAX safety upgrades were rejected over cost

Seven weeks after the second fatal crash of a 737 MAX in March, a Boeing engineer submitted a scathing internal ethics complaint alleging that management — determined to keep down costs for airline customers — had blocked significant safety improvements during the jet’s development.

The ethics charge, filed by 33-year-old engineer Curtis Ewbank, whose job involved studying past crashes and using that information to make new planes safer, describes how around 2014 his group presented to managers and senior executives a proposal to add various safety upgrades to the MAX.

The complaint, a copy of which was reviewed by The Seattle Times, suggests that one of the proposed systems could have potentially prevented the crashes in Indonesia and Ethiopia that killed 346 people. Three of Ewbank’s former colleagues interviewed for this story concurred.

The details revealed in the ethics complaint raise new questions about the culture at Boeing and whether the long-held imperative that safety must be the overarching priority was compromised on the MAX by business considerations and management’s focus on schedule and cost.

Managers twice rejected adding the new system on the basis of “cost and potential (pilot) training impact,” the complaint states. It was then raised a third time in a meeting with 737 MAX chief project engineer, Michael Teal, who cited the same objections as he killed the proposal.
...

Posted by: b | Oct 2 2019 17:49 utc | 29

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