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737 Stuck Manual Trim Technique

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737 Stuck Manual Trim Technique

Old 27th May 2019, 21:37
  #141 (permalink)  
 
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LowObservable
A very astute post Sir, also, the fact that the modern equipment is very reliable in comparison to that of the original 1960 era prototype has the unintended consequence that crew only see non-normal events every six months in the simulator and very rarely see real live technical problems in the aircraft where they are faced with all the additional distractions provided by ATC/Cabin Crew/Pax/Ops/Environmental etc. I've yet to see a simulator that can accurately reproduce the non technical distractions.
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Old 27th May 2019, 22:28
  #142 (permalink)  
 
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Originally Posted by hec7or View Post
LowObservable
A very astute post Sir, also, the fact that the modern equipment is very reliable in comparison to that of the original 1960 era prototype has the unintended consequence that crew only see non-normal events every six months in the simulator and very rarely see real live technical problems in the aircraft where they are faced with all the additional distractions provided by ATC/Cabin Crew/Pax/Ops/Environmental etc. I've yet to see a simulator that can accurately reproduce the non technical distractions.
I donít think we are terribly far apart in our assessment here. The increased use of automation has demonstrable safety benefits, however, more automation should actually increase the pilot training requirements, not lower them. It used to be that it was enough to know how to fly in a low automation world because that is all we had. Now we need to know how to fly in both high and low automation environments depending on how the circumstances play out. Unfortunately, in a continuing effort to minimize training costs, one set skills is increasingly being sacrificed because the other is viewed as good enough for most situations.

Believe me, I understand how it is natural for pilots to get defensive when suggestions of crew error are tossed about. However, as I have previously stated, a crewís performance is intimately related to their training, experience, and environment - not all of which they have much control over. I think observations regarding the crewís performance is really more an indictment of the system that put them in that cockpit than the individuals themselves. Oddly, bending over backwards to overlook crew performance issues is unwittingly playing into the hands of airlines who wish to minimize their pilot labor costs, both in the experience they demand and in the training they subsequently provide. I guess I just donít get why on one hand it is very easy to heap scorn on Boeing for designing the MAX on the cheap and yet give a pass to airlines who want to hire and train pilots on the cheap.
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Old 27th May 2019, 22:39
  #143 (permalink)  
 
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Originally Posted by Smythe View Post
On the subject of trim, I saw that the FAA/EASA information on thumb switches on the MAX, which are trim limited, and that operations at the edge of the envelope would need to be manually trimmed.

Why would there need to be a limit on the thumb switch?
I thought I saw this covered elsewhere, but hereís my understanding. First, the yoke trim switches are only limited in how far nose down they can move the stab. There is no limit on moving the trim BACK toward the ďgreen band.Ē I suspect the reason for this has to due with the fact that the only time one would need to trim that far toward the forward limit would be in a certain unusual flap, airspeed and aft c.g. combinations. In generally, when an aircraft starts approaching its aft c.g. limit, the handling characteristics get a bit more sensitive about the pitch axis. I suspect that Boeing wanted to limit how quickly trim could be applied toward the nose down limit in this region.
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Old 28th May 2019, 02:31
  #144 (permalink)  
 
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Originally Posted by LowObservable View Post

Moreover, what people call a "crew error" usually isn't. It's an indication that crew selection, training and maintenance of competency fell short of what was required to handle an off-nominal situation, and it's consequently related to the degree of abnormality that faced the mishap crew.

Now, I am not sure that even the FTFA-fundies here would argue that the unwarned-against activation of MCAS - a running-in-background gadget that commandeered the most powerful effector on the airplane - wasn't quite severely abnormal. And did it occur on a highly automated airplane? Negatory, sir. It afflicted a Topsy-developed hybrid of a simple 1960s servo-mechanical jet with a 21st-century digital overlay.
Now, let's take this further. "Degree of abnormality" compared to what? If it's "compared to what crews are used to in non-Topsy, post-1980-certificated aircraft" then we have a genuine training challenge.
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Old 28th May 2019, 03:01
  #145 (permalink)  
 
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Originally Posted by fdr View Post
Boofhead; "The aircraft does meet all regulatory requirements, the MCAS system was provided to...."

nonsense.

The aircraft did not meet the rules under Subpart D, and that is the underlying issue. The general comments to date have been related to Subpart C, as there is a failure of the rules to provide adequate protection, just as was the case with AA587, where what was assumed by the industry was not so in reality. In all cases, a situation that requires both pilots on the controls to recover is not compliant, nor is having loads that exceed the momentary force loads to be applied by a single pilot, nor is it acceptable for the aircraft to require exceptional skill or strength.

(c) It must be shown that after any single failure of the stability augmentation system or any other automatic or power-operated system—
(1) The airplane is safely controllable when the failure or malfunction occurs at any speed or altitude within the approved operating limitations that is critical for the type of failure being considered;


must permit initial counteraction of failures of the type specified in ß25.671(c) without requiring exceptional pilot skill or strength, by either the deactivation of the system, or a failed portion thereof, or by overriding the failure by movement of the flight controls in the normal sense.


and my favorite

(a) A warning which is clearly distinguishable to the pilot under expected flight conditions without requiring his attention must be provided for any failure in the stability augmentation system or in any other automatic or power-operated system which could result in an unsafe condition if the pilot were not aware of the failure. Warning systems must not activate the control systems.

Boof', you mention having control issues, so have I; I have landed a 4 engine aircraft without elevators, and I have landed an aircraft after a mid air collision. I don't believe that in either of those cases was it reasonable to have to rely on either the pilot skill or exceptionalism to survive. Both of those aircraft were military so the rules were different, however, after 20,000 additional hours on Boeings and Airbus, I don't believe that it is acceptable to rely on the pilots achieving something that has not been part of their training. Had they done so, then kudos, but don't shoot the messenger, the crews herein were the product of the training system that we have in the real world, and that is the way it is. It is not acceptable to assume that they would be a Chuck Yeager, Bob Hoover, Neil Williams or similar. What on earth do you expect from a 200hr co pilot in the way of support? What do you expect from a product of the current Part 61 syllabus, MCC shambles under FAR or EASA FCL? This is not regional, skin colour or religion based, we have just seen a fairly serviceable NG get seaplane time recorded, just as happens in Indonesia, Chukk, and various other places, including the Bahamas, etc.

The industry is adequate, not much better than that. You cannot bitch about a crew that is confronted with a complex issue that still confounds the manufacturer and regulator 9 months later, and state with a clear conscience that the problem begins and ends in the cockpit. If you show proof that the crew had been trained competently in runaway trim, of dealing with a stabiliser that was so far out of trim that it needed unloading to be reset, that the crew had sufficient altitude to unload a full nose down trim stab before impacting the ground, that the OEM told them of these latent defects in their aircraft design, that the airline had done so, that they had been checked to such a level?

I am angry; I am angry as I have flown Boeing products for nearly 40 years, and the only aircraft that had any discussion on stab airloads was not a Boeing. I have done out of envelope flight test of the B737 and was not aware of the issue. I am angry on behalf of the flight crew that you appear to assume should have skills well in excess of that trained and checked by the system. Personally, I have flown biplanes, WW2 aircraft, and heavy military singles as well as jets, I accept the constraints of those aircraft, as I now fly them as experimental, restricted or limited category, where the basis of their certification is understood by the words in the 21 Subpart H applicable statements. These aircraft do not provide the level of airworthiness that comes from Part 25, and that is fine.

Further comment:
The industry trains to a minimum standard, that is acceptable to the regulator. The airlines could train to higher standards, however, the competitive nature of the industry precludes undergoing astronaut type training for a regular line pilot. The line pilot gets to see components of a training matrix that covers the usual suspects, a fault with no FDE, faults with FDE and requiring reset of a system, faults that degrade performance, faults that degrade handling qualities. We get to practice ILS's which we do every day, and occasionally train on approaches that statistically end badly. We get to do RTO's, OEI's and the usual basics. Often these are assumed to be the limiting case but are not so. The pilots enter the system with varied background, from those that cleaned planes to go fly, or pumped gas for them, to those that the govt paid to do so, and those that could afford training by other funding. Sometimes the airlines HR department is the source of the feed stock and the processing of the new hire pilot. We see former military pilots in the same course as a baron pilot or a 200hr wet CPL/IR/ME ticket. The system trains these people to go fly low viz procedures down to CAT IIIB in short order, with LVTO and similar points of interest. The guys and girls generally do a credit to their background, and cope with what is thrown at them well. In many countries, they get paid less than subsistence wage and are or food stamps at that time. These people fly the high value payload, anyones loved ones from A to B in weather that includes thunderstorms, squalls, snow, hail, rain and shine. They turn up and undergo training as provided by the company. They are not responsible for what the company trains them on, they are the recipient of the training. If there is a deficiency in their training, don't blame the dead crew in the bottom of the smoking hole for not being trained to a level that would ensure that they can cope with unknown and unexpected events.

Every day around the world, the system generally works. It could be better, but making it better is not the responsibility of the 200hr copilot or 4000 Captain, they are the result of the system not the cause. If you are able to deal with every situation that may come along, then great for you. A number of pilots can do that, many will get close, and many won't deal with situations that have not been trained.

38 years of safety and accident investigation in the military and airlines, and the main takeaway IMHO is to keep things simple, and to understand that crews faced with events often do not respond as they do in the simulator.
Sir,
I have great respect for your experience. However, do you seriously believe that an "average" reader of this forum isn't already aware of all of this? The problem is not realizing the industry has pervasive issues, it is the improbable expectation that the people who caused the systemic failure will fix it. Aircrews aren't going to get more competent, but better automation design and a return to a reasonably honest and evenhanded certification process are certainly feasible goals, which would be hurried along a bit by the designation of some senior level scapegoats at the FAA and Boeing.
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Old 28th May 2019, 04:46
  #146 (permalink)  
 
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. I guess I just don’t get why on one hand it is very easy to heap scorn on Boeing for designing the MAX on the cheap and yet give a pass to airlines who want to hire and train pilots on the cheap.
I don't think the issue was that Boeing was doing anything on the cheap, it would have cost absolutely nothing more to have the MCAS system be a bit more failsafe-ish by comparing the two sensors. The basic issue is that Boeing promised something that was impossible, an aircraft functionally identical to the 737-NG but with larger engines in a different place. They ended up using software to simulate a 737 on an airframe that pretty much anybody could see would have different aerodynamic characteristics. They didn't do this to save money, they did it to save development and certification time in order to get a desperately needed product to market. The software fix was seductive -- it was elegant, simple, and Boeing had already used software to deal with a potential program-ending aerodynamic flaw in a previous model.

The desperate need for the MAX to be "just an upgraded NG" led to an engineering/management problem known as "the Emperor's new clothes." Anything that violated that basic assumption is not acceptable; they apparently went as far as to reorganize the test pilots out of the development program when they raised concerns. Using two sensors would have meant admitting that the Max was NOT an upgraded NG because if the sensors disagreed you had to turn off MCAS which meant that now you have different (and non conforming) flight characteristics. Rather than document the issue, they swept it under the rug and pretended that it wasn't there. This goes for what they told the pilots as well, which was nothing that would upset the party line. Refusing to acknowledge that the Emperor is naked even persists after the accident; this was not a computer failure or a programming flaw, it was a trim runaway like could happen on any 737. Why? Because the MAX is just an upgraded NG, that is why.

Now apparently even that approach has bitten them in the rear end, as by insisting that the accidents (!) were simply mismanaged trim runaways the obvious question is "how do you properly manage a trim runaway?" and the answers are not looking good for either the NG or the MAX. It doesn't help at all that the simulators (which is the only place to practice this very dangerous condition) apparently do not reflect how hard the procedure is in real life. At some point even the most dedicated Boeing FTFA supporter is going to have to stop suspending disbelief and admit that this was a pretty big engineering snafu, and not pilot error.
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Old 28th May 2019, 05:20
  #147 (permalink)  
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Ed, this forum is open presumably in the furtherance of aviation centric matters, which include safety, design, operation and training as some aspects. Opinion flows relatively freely and that freedom results in all views being presented, the loudest and most persistent being accorded column inches on the page.

The industry overall works, it has bad days and they are catastrophic for the people concerned, but less so for the industry at large. Passengers and shareholders have voted with their check books to drive the industry in the direction it has gone. That direction has resulted in an explosion of capacity, routes and frequencies, resulting in a demand for flight crew that places pressure on supply of trained personnel. Training standards meet financial bottom lines every day. The regulatory system has been under stress for a long time, and competition for competent staff places strain on the regulator capacity. They cope, as does everyone else.

The OEM is also in a competitive industry, and deals as best they can to produce a product that can compete. The engineers doing design have firewalls to assure the ODA DOA process remains functional. For the MCAS it appears to have slipped a cog. Each part of the system includes humans working under stress, and making deliberations under uncertainty. If we miss out in the imagination to cover all eventualities in a failure mode analysis before the fact, then that is the limit of being human.

Blaming flight crew for not being competent in a dynamic complex event does not improve the long term system reliability. Blaming a 200hr FO, or a 4000hr Capt for not being chuck yeager does not cure the problem. Simplifying procedures through strengthened risk analysis, and better system design flowing from more robust faikure mode analysis is a path forward but doesn't happen quickly. The industry will put a bandaid on the problem with specific fault mitigating training, and that will do in the short term along with better event centric rectification.

The training for all conceivable and inconceivable events for the crew doesn't get done within the cost base of the industry as it stands.

This forum has had numerous comments decrying the competency of the flight crew in these events, contending they are primary causation of the outcome. It is unfair to do that in this case IMHO, and beyond that, the assumption of goodness in those that consider that the fault would have been easy for a competent crew to deal with is potentially a risky assumption. We can hope that following comprehensive review, system redesign,the training that results will increase the likelihood of a successful outcome by any flight crew, not just the Yeagers out there. At that point, if the crew cannot cope with the same problem, then there is a possible crew issue. Before that point, the failure is global. The ability of training reinforcement to mitigate operational risks has a patchy record, we still plant planes in the rough at both ends of the runway, from all cultures and nationalities.
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Old 28th May 2019, 06:50
  #148 (permalink)  
 
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Is it so obvious?

Originally Posted by boofhead View Post
I have had this problem (runaway trim) and it was difficult to fly the airplane but I am still here so it was not impossible. I did not give up and flew the airplane to the ground with full nose down trim and because of a broken trim cable, no way to reverse the problem. I also flew the 737 for thousands of hours (although never had the trim runaway on that aircraft). I am not an "armchair" pilot and I do know how to fly and how to perform an emergency checklist. I am appalled at the lack of professionalism shown by the pilots in the two 737Max aircraft and even more appalled at the way so many on this thread are preferring to blame Boeing rather than the real cause of the tragedies because of political correctness. If they get their way they would put Boeing out of business and who would benefit then?

No aircraft is immune from failures of some type, and it is the pilot's job to fly it nevertheless and to keep the people who are placing their trust in him/her safe by at the least maintaining an average level of skill and knowledge. Which is all it takes. You don't have to be a super hero.

Fix the real problem. The human element. Take it as a warning of what will happen if we continue to dumb down (to the lowest common denominator as has been suggested we should be doing). Maybe we should be replacing the pilots with computers. They could not do any worse.
If it was as obvious and simple as you try to convince us:
- why did ALL the CAAs ground the aircraft?
- why did Boeing already fly 300 hours of additional test flights?
- why has Boeing not yet provided any fix to the FAA, which was expected six weeks after the Lion Air accident, and then in April 2019, and then before the CAAs meeting last week (nothing yet arrived)?

When you give me reasonable answers to these basic questions, I shall then support you on the training which is an issue, everywhere in the world, but likely not the main issue for the two B737Max accidents.

Rgds
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Old 28th May 2019, 07:07
  #149 (permalink)  
 
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Originally Posted by Water pilot View Post

At some point even the most dedicated Boeing FTFA supporter is going to have to stop suspending disbelief and admit that this was a pretty big engineering snafu, and not pilot error.
I donít recall a single person denying that there was a huge problem with the MCAS design. This is not an either/or situation. It is NOT a case that all the fault lies with Boeing OR all the fault lies with the crew. There are issues with both. The MAX/MCAS design issues are being given the most intense scrutiny of any commercial aircraft that has been produced in recent history. I donít think we need to worry that something is going to slip by the army of engineers, regulators, and lawyers that are circling the good ship Boeing. However, if in all the determination to pin these accidents on Boeing, and only on Boeing, we ignore the what the data is also saying about the level of crew proficiency, then we just help perpetuate a culture that is in a seeming race to the bottom to see how low airlines can set the bar for pilot training standards. Iím sure those airlines are more than happy for the cover as they funnel resources away from better training and into the pockets of investors and managers.
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Old 28th May 2019, 07:22
  #150 (permalink)  
 
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Red face

Originally Posted by GordonR_Cape View Post
I find it moderately interesting that the case chosen for evaluation is runaway nose up trim, which is an urgent stall hazard. Presumably nobody in 1982 could visualise the hazards of runaway nose down trim, perhaps due to the limited range of trim travel allowed by the autopilot in the flaps down condition. As the article notes, assumptions made five decades ago, are still propagating through today's 737 flight controls.
You seem to have missed the sentence "if nose up trim is required". Somebody in 1982, did in fact "visualise (sic) the hazards of runaway nose down trim".
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Old 29th May 2019, 01:34
  #151 (permalink)  
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safetypee's reply to a post of mine where I'd more or less divided up the blame between Boeing and, not the pilots per se, but the system in which they flourish - or not.

Loose rivets, # 135,
Your certainty about the technical aspects is not necessarily the same certainty about pilot performance. Technology, aircraft design, and manufacture, can be judged against hard requirements, whilst humans have no published requirements for their ‘construction’, and where output performance is judged by other, ill-defined humans, in situations seldom related to extreme events.
Hmm . . . preaching to the converted. I was still a young man when I had to deal not only with an alcoholic and probably psychotic captain, for weeks, but while a management and training staff that promised and promised to remedy the situation, simply never did. This guy had a long career behind him but still managed to singe the passengers queuing behind the jet pipe and then take off three tonnes overweight in that little BAC 1-11. That's not a mistake. He was just not right, but the manager's lacking was wrong to the point of being sinister. If you've any ideas about Us being better than Them, I could fill in a year's worth of bizarre happenings leading up to me walking out of the best paid job I'd ever had. Ill-defined humans. That's a good term.

Despite spelling out that extraordinary situations can arise with any crew, I still maintain the ET crew were woefully inexperienced. It could be I'm plain jealous. It was 8,000 for PIC and 4,600 for FO when I moved over to the 1-11 after two years on Viscount. I clearly recall something 'clicking' at about 500 hours - at last I felt really at home on type.

Even with an experienced skipper, so much depends on their wellbeing and indeed, how they react when one day they are confronted with an extremely demanding emergency. Most of us need that other pair of experienced hands in those moments.
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Old 29th May 2019, 05:07
  #152 (permalink)  
 
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Originally Posted by Bidule View Post
If it was as obvious and simple as you try to convince us:
- why did ALL the CAAs ground the aircraft?
- why did Boeing already fly 300 hours of additional test flights?
- why has Boeing not yet provided any fix to the FAA, which was expected six weeks after the Lion Air accident, and then in April 2019, and then before the CAAs meeting last week (nothing yet arrived)?

When you give me reasonable answers to these basic questions, I shall then support you on the training which is an issue, everywhere in the world, but likely not the main issue for the two B737Max accidents.

Rgds
They did not ground the aircraft until forced to by the negative publicity and apparent anger from the public. They did not ground the aircraft because of a fault in the aircraft as it was accepted by those authorities including the FAA until the public pressure from those who were not qualified to apply it but were emoting and not analyzing nor applying scientific reasoning. For example the fact that the pilots of those aircraft did not follow the checklist for the emergency was hardly discussed but it should have been. Why did those crews fail so badly? Were they incompetent? Poorly trained? Inexperienced? To date none of those possibilities have been looked at, even cursorily.

Boeing is doing its job to thoroughly test the airplane. They could not just zip around the pattern and call it good, even if they were sure there was nothing wrong with the design or construction of the airplane. The public, driven by the blood in the water and wanting to bring down Boeing, would never tolerate that. Facts be damned. I still read that the MCAS system was put in the aircraft to prevent a stall when it has nothing to do with that. I read comments by pilots on this forum who buy into the ill-informed and emotive reporting by the media (when will we learn that they have nothing to contribute to the news but their twisted agenda?) that ignore the facts and join the pile-on to destroy the company that has done so much to make aviation the most successful and safe industry and public service in modern times. For what reason? Politics? Ignorance? Follow the leader?

Boeing is working on a fix. They could have provided it on day One. That fix is to leave it as it is. There is nothing they need to do and they will never find anything that would satisfy the great unwashed who do not understand the subject. The airplanes were always flyable. There was always a procedure to fly them safely with the MCAS system not working as it should. There were at least six ways to stop those airplanes from plummeting into the ground out of control. After the investigation is over Boeing will not be able to come up with a fix because there is not a fix available because there is not a design defect or construction error that needs to be fixed. It is like having a car hit a pothole on the road and the driver allows the car to cross the median and kill the people in the other lane by running into them head on. Was the fault the road maintenance crews? The people who issued that driver a license? The tire manufacturer? Or was it simply that the driver did not know how to handle that type of problem and lost control? My daughter nearly did that when she hit a patch of ice that had run over the road from a broken water main in the winter. She was lucky that the other driver immediately drove his car off the road into a ditch to avoid the head on accident because my daughter could not get her car back onto her side of the road. Two of my daughters were on board that car and I could have lost both of them. I could have kissed that other guy, a middle aged chap who had good reflexes, but I had to blame my daughter a little because her first instinct was to slam on her brakes which caused an instant loss of control. She should have steered the car through and braked on the other side. I also know that she was facing something way out of her experience and she did not panic. She got her car under control and nobody was hurt, But these pilots managed to kill over three hundred innocent people despite being trained and qualified, including how to handle this specific problem of runaway trim. There is a difference between blaming a driver of a car who had never been given training on how to handle a sudden skid or had never experienced it before and a professional who had been so trained but failed to recognize the problem and failed to act correctly. Who allowed himself to lose the plot and give up. I would have respect for someone who went down fighting as did the pilot of that FedEx 767, or the 747 pilot in Dubai, even the ValuJet pilot, rest their souls, but to throw a perfectly good airplane into the ground simply because he lacked basic flying skills is not acceptable to me.

Those pilots should not have been there. They did not know what to do. Whether that was their fault or the trainers, or the management, the regulators or the shortage of pilots that is making all of us lower the bar I don't know and if it is not examined and if something is not done to correct the problem when it is identified we can expect to see more of the same.
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Old 29th May 2019, 06:25
  #153 (permalink)  
 
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Couldn't agree more Boofhead
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Old 29th May 2019, 07:31
  #154 (permalink)  
 
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Originally Posted by boofhead View Post
They did not ground the aircraft until forced to by the negative publicity and apparent anger from the public. They did not ground the aircraft because of a fault in the aircraft as it was accepted by those authorities including the FAA until the public pressure from those who were not qualified to apply it but were emoting and not analyzing nor applying scientific reasoning. For example the fact that the pilots of those aircraft did not follow the checklist for the emergency was hardly discussed but it should have been. Why did those crews fail so badly? Were they incompetent? Poorly trained? Inexperienced? To date none of those possibilities have been looked at, even cursorily.

Boeing is doing its job to thoroughly test the airplane. They could not just zip around the pattern and call it good, even if they were sure there was nothing wrong with the design or construction of the airplane. The public, driven by the blood in the water and wanting to bring down Boeing, would never tolerate that. Facts be damned. I still read that the MCAS system was put in the aircraft to prevent a stall when it has nothing to do with that. I read comments by pilots on this forum who buy into the ill-informed and emotive reporting by the media (when will we learn that they have nothing to contribute to the news but their twisted agenda?) that ignore the facts and join the pile-on to destroy the company that has done so much to make aviation the most successful and safe industry and public service in modern times. For what reason? Politics? Ignorance? Follow the leader?

Boeing is working on a fix. They could have provided it on day One. That fix is to leave it as it is. There is nothing they need to do and they will never find anything that would satisfy the great unwashed who do not understand the subject. The airplanes were always flyable. There was always a procedure to fly them safely with the MCAS system not working as it should. There were at least six ways to stop those airplanes from plummeting into the ground out of control. After the investigation is over Boeing will not be able to come up with a fix because there is not a fix available because there is not a design defect or construction error that needs to be fixed. It is like having a car hit a pothole on the road and the driver allows the car to cross the median and kill the people in the other lane by running into them head on. Was the fault the road maintenance crews? The people who issued that driver a license? The tire manufacturer? Or was it simply that the driver did not know how to handle that type of problem and lost control? My daughter nearly did that when she hit a patch of ice that had run over the road from a broken water main in the winter. She was lucky that the other driver immediately drove his car off the road into a ditch to avoid the head on accident because my daughter could not get her car back onto her side of the road. Two of my daughters were on board that car and I could have lost both of them. I could have kissed that other guy, a middle aged chap who had good reflexes, but I had to blame my daughter a little because her first instinct was to slam on her brakes which caused an instant loss of control. She should have steered the car through and braked on the other side. I also know that she was facing something way out of her experience and she did not panic. She got her car under control and nobody was hurt, But these pilots managed to kill over three hundred innocent people despite being trained and qualified, including how to handle this specific problem of runaway trim. There is a difference between blaming a driver of a car who had never been given training on how to handle a sudden skid or had never experienced it before and a professional who had been so trained but failed to recognize the problem and failed to act correctly. Who allowed himself to lose the plot and give up. I would have respect for someone who went down fighting as did the pilot of that FedEx 767, or the 747 pilot in Dubai, even the ValuJet pilot, rest their souls, but to throw a perfectly good airplane into the ground simply because he lacked basic flying skills is not acceptable to me.

Those pilots should not have been there. They did not know what to do. Whether that was their fault or the trainers, or the management, the regulators or the shortage of pilots that is making all of us lower the bar I don't know and if it is not examined and if something is not done to correct the problem when it is identified we can expect to see more of the same.
What a wonderful post! You deserve a premium from Mr Boeing!

Just some extracts form your post:

"They did not ground the aircraft until forced to by the negative publicity and apparent anger from the public" Until the aircraft was grounded worldwide, the public was not involved nor reacting....

"They did not ground the aircraft because of a fault in the aircraft as it was accepted by those authorities including the FAA" The FAA seems now to have less willingness to accept the aircraft "as is".

"wanting to bring down Boeing" Any evidence of that?

"That fix is to leave it as it is" Even Boeing did not try this one, marvellous!

"But these pilots managed to kill over three hundred innocent people despite being trained and qualified, including how to handle this specific problem of runaway trim." At least for the Lion Air pilots, they cannot have been trained on the consequences of MCAS operation as MCAS was not known by the pilots, NOT INCLUDED in the Boeing's manual; it even seems that FAA was not fully informed of the working details of MCAS.

You should suggest creating a worldwide certification agency and apply to be the Chairman; you have the required talents.

.
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Old 29th May 2019, 08:53
  #155 (permalink)  
 
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Wonk's First Rule of PPRuNe

"As of November, 2018, any thread containing the words "737" or "Max" will, before being terminated by the moderators and before reaching a maximum of 130 posts devolve to an ongoing argument over whether or not the pilots were solely (or significantly) responsible for the Lion Air and Ethiopian crashes,"

It should be noted that while Wonk is excited to publish Wonk's First Rule, it remains really unfortunate given that this thread raises a critical flight-safety issue, no matter who is doing the flying, and as fdr has (as always) eloquently identified there is (and should be) a long and ongoing discussion about what the ramifications of a horizontal stabilizer that can be frozen in place within the operating envelope of the airplane are for operators and pilots of the 737.

Of all the post-Lion Air threads this is the one that is most critical to stay alive. If you need/want to argue about blaming the pilots I suggest you go to the ET thread, where there are literally thousands upon thousands of posts for you to digest one at a time. Here the discussion should be about the completely anomalous discovery of the inadequacies of the trim system in post Classic 737s, a discovery that places the airworthiness of not just the Max, but the NG in doubt as well.

Warm regards-
dce
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Old 29th May 2019, 10:54
  #156 (permalink)  
fdr
 
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Originally Posted by wonkazoo View Post
"As of November, 2018, any thread containing the words "737" or "Max" will, before being terminated by....
dce

That would be nice.

I don''t see any evidence of posts intending to harm TBC, or their product. EASA raised concerns back with the NG trim system which shows the extent of missing the opportunity that existed. The event highlights the design, certification standards, and, yes, training matrix as well as adequacy of information provided to the flight crew in training and checking.

Bottom line is the flight crew are just the ones left holding the consequences of the global deficiencies. That some crew may be able to handle such an event is not a basis for system safety.

Cheers
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Old 29th May 2019, 11:21
  #157 (permalink)  
Psychophysiological entity
 
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I think this is perhaps the most important topic ever to have been discussed on PPRuNe. Some weeks ago I suggested threads dedicated to different facets of the subject. Although Tech Log might normally be appropriate for the technical issues, I wondered if a sticky that could be added to on R& N might be more at hand.

I had hoped there'd be a way to lay out all the technical information so that it could be added to but not constantly repeated. For example, the action and the limitations of the trim switches. The logic here is that the limitations of the trim action has been raised in recent days, and I for one had forgotten the subtleties.
The hidden column switch's modified functionality is another example of a highly relevant and fairly complex issue. But in over 6,000 posts I still have to trace the circuitry to make some sense of a doubtful consensus. Tough to get a clear picture.

I entirely agree the training issues should be separate, though it's inevitable a technical thread cross-referencing will be needed.

And then there's Boeing and the FAA, a major subject of course, but while it would be good to have it focussed in yet another thread, to be able to link to known reference points in the technical thread would be a very useful tool.

I don't know who would do all this work as I doubt an open thread 'sensible use' policy would be free of repeated strong opinion. Yes, I'm one of the guilty ones.

There has been so much good data posted since November, but so many re-postings and confused not-so-new questions make it hard to sort the wheat from the chaff, but as implied, this is perhaps the most important crisis to ever hit civil aviation and it could go on for years. Perhaps it deserves an unprecedented PPRuNe structuring that would work in the long term.
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Old 29th May 2019, 13:15
  #158 (permalink)  
 
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Thank you for sharing your anger, Boof.

Goodness. Are we saying that the grounding was driven by "negative publicity"? What, pray, caused that publicity? If your answer is "two closely related total losses of a brand-new airplane" you may take a cookie from my desk. How do you expect humans to react? How do you explain that aircrew unions were among the leaders of a call for grounding?

The media "have nothing to contribute to the news but their twisted agenda?" Hmm, Boof, I bet they're The Real Enemy Of The People too. Or maybe you're just mad that they unearthed Sinnett's comments after crash #1.

And by the way - even as SLF I think your remark about MCAS...

I still read that the MCAS system was put in the aircraft to prevent a stall when it has nothing to do with that.

...is nitpicking at best. MCAS was installed to restore a linear relationship between stick force and AoA, which is required for certification. And why is it required for certification, boys and girls? That's right, to reduce the chances of entering a stall.

Oh, I'm sure you're a great Dad and all, but you live in a part of the world that has hard freezes and you never told your kids how to handle ice?
LowObservable is offline  
Old 29th May 2019, 14:35
  #159 (permalink)  
 
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Buffoon!

I get it now Boofhead.
How appropriate.
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Old 29th May 2019, 16:11
  #160 (permalink)  
 
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I confess I don't understand your objections to what I am saying. If a stall strip comes off an airplane in flight and then the pilot subsequently finds on approach that the wing is dropping, should he give up? Just let the airplane fly into the ground? I would posit that there are pilots out there just waiting for that opportunity. He does not have to know why the wing is dropping all he has to do is react and recover.

If a pilot gets ice on the tailplane and experiences tailplane stalling should he think "I have not been trained to handle this so I just give up?" If a pilot finds that after lift off his airspeed indicator is not working because of ice/tape/bugs/malfunction is he allowed to just give up and throw the airplane into the ground? He has a sudden engine failure, follows the drill but forgets to feather the prop should he just sit there and allow the airplane to roll itself up into a ball? Even distractions in flight have caused the pilot and his passengers to die. All these things have happened and hundreds of people have died as a result, often with professional pilots flying the aircraft.

It is not important why the stab system failed. It could have been a myriad of things. All a pilot has to do is fly the airplane. It happens many times without a problem and we don't even hear about it. Engines fail and pilots do the right thing, they handle icing, mechanicals, recognize subtle incapacitation, low oil pressure, engine failures, prop runaways, incipient stalls, seat belts hanging out of the door, out of balance loading, bird strikes and more and don't decide to kill themselves and their passengers. That is what we expect and deserve from a professional pilot.

Sure we fix the problem of the MCAS. We increase maintenance to ensure the stall strip does not come off. We give the pilots training to handle what we think might happen in his flight, but we can't anticipate everything and therefore we must have professional flight crews who can handle the unexpected and that means they have to be able to fly their airplane all the way to the ground without giving up.

If they fail, we have to be able to see that as not only a warning to build our airplanes better (add stall warning, anti ice equipment, better passenger restraint, fire bottles etc) but also recognize when pilot training has failed. And do better. But if we deny the pilot element and do nothing we better get ready for the body bag companies to increase their stock prices.
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