Airline pilots have been complaining for months about Boeing's deathliner


Originally published at:


The problem only exists if we talk about it


No consequences? No problem!


Well why would anybody listen when workers complain? We all know they just want to not work and collect their welfare checks in their Cadillacs. No way their concerns could be genuine - we would have heard it from important people by now.


It is incomprehensible why we should rely on software to fly these planes. Why is it standard operating procedure to engage an autopilot immediately after take off? The pilot should be flying the plane – it is their experience and ability to respond to situational changes that everyone’s lives depend on.

When you hear a pilot has thousands of hours of flight time, does this mean he or she actually only has five minutes off the runway and final approach per flight?


If I recall correctly, the problem is that the autopilot actually takes control from the pilot when it thinks (incorrectly) the plane is about to stall, so it noses down to prevent the stall. The buggy software gets stuck thinking the plane is still about to stall even after nosing down, so it doesn’t let the human pilot bring the nose back up.


I can’t believe people believe corporate interests are prioritized over public safety! Why, look at this scandalous, scurrilous screed that was published by anti-business fearmongers at [checks notes] uhhhhh, Business Insider:


Okaaaay….So this sounds more like somebody has installed a piece of software that is designed to crash planes…hmmmm.

We need to get away from light switches that require software to function. There should be an “OFF” button, and pilots should know how to get to it.


These auto features have failed even on existing older planes, where there’s a sensor malfunction and the software over corrects. I do believe there are ways for pilots to override whatever the software is doing but the huge issue is that the pilot has to have an idea of what is malfunctioning otherwise whatever they do will only make the problem worse.


Yes, I just re-read some of the news stories, and there IS a way for the pilots to override the software, but with crappy documentation a pilot unfamiliar with this “safety feature” would have trouble figuring out how to do that in time.


Love to pay too much to get into a metal machine that’s been programmed to commit suicide.


I’m sure we can trust Trump’s FAA to make the right decision here. It’s not like the head of Boeing is just ringing up Trump asking for favo— oooohh…


from the dallasnews-article:

Records show that a captain who flies the Max 8 complained in November that it was “unconscionable” that the company and federal authorities allowed pilots to fly the planes without adequate training or fully disclosing information about how its systems were different from those on previous 737 models.

its just unfuckingbelivable.


The Ethiopian Airlines pilot whose jet crashed killing 157 people had reported flight-control problems, the company said on Wednesday, as it prepared to send the black boxes to Europe from a disaster that has rocked the global aviation industry…

this is somewhat unusual; normale procedure would be to send the blackbox to the country of the manufacturer. I could be wrong and its just about time (overseas vs fast) but maybe, just maybe the Ethiopians dont trust the us-authorities that much after the non-grounding in the us.


Hmmm… I wonder why the US might not be the most reliable authority in judging the flight worthiness of these planes.



you have to be shitting me! this fucker installs his minions even in the FAA?!?


This just blows my mind. What a “favour” it will be if another one crashes, killing hundreds of Americans, after every other country has grounded them. So good for Boeing, that, what a great favour.


Obviously the autopilot is programmed to tilt the nose down as it travels over a round Earth. Proof that world is flat! /s


Good, short explanation what a Manoeuvring Characteristics Augmentation System (MCAS) is for; the MCAS seems to be at the heart of the problem, as far as anyone can tell at this time.


My understanding from following some threads on Flyertalk and is the system involved (MCAS) is actually a safety feature designed to detect imminent stall conditions (like what occurred on Air France 447) and automatically pitch the nose down in order to avoid an aerodynamic stall. Pilots have complete override authority and can disable the system with a flip of a single switch.

Speculation is that the pilots involved with both the Lion Air and Ethiopian Air crashes were not given proper training on how and when to disengage the MCAS system.

Here is a relevant post which describes some of the details:

MCAS is not a new “flight control system”, per se, as the 737MAX retains essentially the same hydraulic flight control system as every 737 that preceded it, which is why the MAX has the same type rating as every other 737 that’s ever flown and only requires some differences training for existing 737 pilots to legally fly it. That’s why the FAA ultimately agreed with Boeing and determined that the MCAS did not comprise such a substantial deviation from the flying characteristics of the 737 that would require a new type certification.

The news media briefly (and irresponsibly, I might add) pushed a sensationalist story of some all-new “rogue” system that Boeing secretly installed on the 737MAX flying the aircraft into a dive despite the best efforts of the pilots.

Indeed, for better or worse, it’s the pilots that have the final say in control inputs, as compared to FBW aircraft like the 777, 787 or the post-A320 Airbus line. Given that, it is important to understand that MCAS is a safeguard designed to assist pilots in stall avoidance during a limited set of circumstances, namely:

  • high angle of attack;
  • clean configuration with flaps retracted;
  • high bank angle; and
  • autopilot disengaged.

If those conditions are not met, the MCAS is inactive. Even in the event of an unwanted MCAS activation, it can be disengaged momentarily or cut out completely. If it engages in the normal course of operations, without an instrumentation failure (which is now expected to be the root cause of the Lion Air crash), it is to get the airplane out of a critical AOA situation where an aerodynamic stall can be induced. The issue is that the Lion Air 7M8 ‘thought’ it was approaching a stall, and engaged the MCAS to push down the nose to correct the condition. Unfortunately, it appears as though the pilots weren’t prepared to manage this situation, and a combination of factors led to the crash… not unlike AF447.

Still, an instrumentation failure, or a flight control failure (such as pitch trim runaway) are not unique to the 737MAX and procedures have long existed for crews to follow in order to rectify the condition. Human factors can and will interfere with a crew’s diagnosis and management of these situations, especially in critical phases of flight, and the combination leads to accidents. Again, nothing new here:…h-trim-runaway

Like with anything tragic that occurs under these circumstances, the media does have a tendency to sensationalize the facts and jump to conclusions. Airplane crashes are rare today precisely because of investigators who thoroughly review every detail of previous crashes and recommend changes to avoid future issues. It’s unfortunate and tragic that people lose their lives in these events and nobody wants to see another crash.

It is premature to assume the cause here but it’s likely a combination of factors including inadequate training, pilot error and unfortunate circumstances that converged together to bring down both of these planes. I do not believe the plane is inherently unsafe or flawed. US based airlines also usually have a higher degree of pilot training than some foreign airlines which adds to the margin of safety.

And here is a post from a pilot with some additional details:

An MCAS event will provide ten-seconds of nose-down trim input at half-speed followed by a five-second pause. This cycle will repeat until the condition triggering MCAS is resolved. The result of a nose-down trim input is that it makes the aircraft’s nose “heavier” requiring increased back-pressure on the control yoke to hold the nose in its current position. The reason for MCAS is to bias the nose down in situations where the airplane is dangerously slow and in danger of an inflight upset.

When you are hand-flying a 737 it frequently rolling in trim without your input. There are various systems that are doing this for various reasons. MCAS is a new system which can also run the trim when you are hand-flying the airplane. The pilot has no way of knowing which system is responsible for any particular trim input. All we know is that the trim is moving. If the trim is moving in a direction that we do not want we use the trim switches (thumb switches on the control yoke) to correct the mistrim condition which immediately stops any of these inputs and retrims the aircraft toward the desired trim state. Those switches are being used frequently while hand-flying the airplane in normal operations. In the case of MCAS, this starts the five-second pause and will be followed by another MCAS event if the underlying cause of the MCAS activation has not been corrected.

In the first accident flight (Malaysia) the accident crew, according to the released DFDR data, had 26 MCAS events and stopped 25 of them with opposite trim input. What they apparently failed to do was to complete the runaway stabilizer procedure which would have led them to throw the two stabilizer trim cutout switches which are within easy reach of either pilot. This would have stopped all electric trim inputs and left them with manual trim with which they could have completed the flight safely. We don’t yet know why they didn’t complete the procedure. We also don’t know why the airplane was dispatched several times after similar stab trim events without the underlying problem being fixed.

There has not been any information released about this new accident that can either confirm or rule out a stabilizer runaway situation but that is something that will be known quite quickly once the DFDR is found and the data analysed.


Look all the capitalists fly private jets. The risk is going is acceptable to them.