Even including that model 737, it's extremely safe. Check out the wiikipedia page on aviation safety and try to actually understand the numbers on the two graphs of passenger fatalities vs. year. It's improved by actual (not figurative) orders of magnitude since my first flight 50 years ago. Add those two incidents to the chart and see how it looks.

There are so few annual fatalities that that's true nearly *every* year for some model. In some years, a single model is responsible for all of them. In 2018, the 737-700 was responsible for 100% of US commercial jet fatalities (one person killed in WN1380).

And they did before, which is why planes aren't falling out the sky right and left. As far as reports have indicated, Boeing started working on fixes after the Lion air crash. Design changes in aircraft and space systems take a *lot* of time because there's always a risk of unintended consequences.

It's still not entirely clear that there weren't multiple faults that led to what many are interpreting as just an MCAS fault. When I look at the altitude and measured AoA that the NYT showed today, that seems more likely, not less.

I never said Boeing couldn't have done anything.. There's almost always *something* that could have been done that was overlooked. Enormous numbers of labor hours go into fault analysis to prevent incidents and analyze them when they occur to get the causes and prevent them happening again. That's happening in this case, too. The difference now is the number of people who are used to getting information updates every few seconds and are jumping to conclusions and assumptions with incomplete information.

The problem, from a pilot's perspective, is that you let yourself get into the situation where you are disabling the electric trim with the stabilizer at, or very near, the full nose-down position. That is a difficult situation to fly out of.

It would be great if we had perfectly designed machines made of parts that never failed. That's for the engineers to work on. Us pilots know that the machines will never be perfect so we have to be prepared to handle the situations when components, procedures, or human factors fail. Some here may remember a day, over 45 years ago, when a burned out light bulb brought down an L1011 jumbo jet. We've learned a lot since then. By being prepared with knowledge, experience, and strategies for threat and error management we have been able to put together the safest form of transportation in the world. We're still working on perfect.

I guess my question would be why the procedure mandates to turn off electric trim right away and not has an additional step before that to bring the airplace back into proper trim using the electric trim. I assume the reason for that is that the procedure was originally written for the situation where there is a problem with the electric trim. But that is not necessarily the case here - the electric trim per se works fine, it's just being triggered incorrectly by the MCAS. Am I understand that correctly?

Interesting to read through the many thousands of comments on pprune, the pilots rumor board. One poster likened the 737 Max to a short legged dog that had been bred and bred and bred to the protest of true animal lovers. There is a lot of discussion that the Max has a whole host of problems other than MCAS, and not only are Max's leg short, they are very close together.

Max is a good name for a dog.

Please let's stay are away from characterizing posters -- it is rarely complementary and does not add value to the discussion. And with each ever strident retort, the discussion degrades.

And it is against the FT rules
Such posts have been and will be deleted.

WineCountryUA
UA coModerator

Well, the burned out light bulb didn't cause the crash; the crew's preoccupation with it, failing to continue to monitor other gauges, did. @:-)

I'm in total agreement that we will likely never be perfect in the air. But in this case, with this particular model of 737, we can obviously do better. 350 humans had to die to show this.

A little bit late to the game but.... I was actually on a 737 Max 9 flight mid-flight between LAX and KOA when it was canceled. My GF was a bit nervous about flying on a Max. However the upgrade to first helped calm some of the fears :P When I landed I saw that the flight back to the Mainland was canceled.

With an unschedule MCAS runaway you can stop the runaway and retrim with the primary electric trim. If the failure causing the runaway was in the primary electric trim system then you might not be able to do so and getting the electric trim disabled as quickly as possible would be critical. There is no time to first figure out what is causing the runaway, if the runaway responds to opposite primary trim, then decide when the disable the system. The problem that all three flights had (incident and two accident flights) is that they allowed the unscheduled MCAS events to continue unchecked for an extended period of time.

That has not been my experience. In fact, my experience has been just the opposite.

The longer NGs (-800/-900) have an issue with high landing speeds. This comes from the extended fuselage and the need to provide more tail clearance. Normal landing flaps settings are Flaps 30 and Flaps 40 but both models have an undesirable "wing wagging" at Flaps 40 so Flaps 30 is most commonly used unless Flaps 40 is required for the conditions. The Flaps 40 landing speed is roughly 8 knots slower than Flaps 30. The MAX has fixed this problem and so Flaps 40 is the normal landing flaps setting with its lower landing speeds. The width of the MAX's gear is identical to the NGs so no change there. The MAX's weather radar system is significantly improved as is the larger vertical situation display which improves situational awareness on your vertical profile.

Thanks for sharing. This kind of gets to my other point though +/- 10/month is about all the play either Airbus or Boeing have in production. There just isn't flexibility in the model for larger increases or cuts.

Isn't this part of the problem? I have been watching Mentour's videos and learned a lot about airplanes. It seems the pilots really need to know very well how planes work and behave. With Boeing not documenting these deficient and illogical designs and behaviors, how can the pilots know? (I still think there is a reason why they designed things this way that we don't yet know - someone might have assessed and determined it is better to have MCAS do this since it is even more risky if MCAS did not.)

At work, we struggle with making something "doc/training" issues or making changes to the system and how many "doc/training" issues can be there when the system becomes too difficult to use? Can you really expect people to remember all these things in an emergency?

We are, and always have been, training in dealing with a runaway stabilizer. It's not even unique to the 737--all transport jets have a similar procedure.

There's nothing in the information that has come out since the accidents that would be helpful in dealing with an unscheduled MCAS event. The Ethiopian crew was aware of the unschedule MCAS event on the Lion Air flight and how to deal with it but it didn't help.

If using electric trim inhibits MCAS until five seconds after electric trim is released, and the ET pilots used electric trim before the last MCAS activation before the crash, do we know why the pilots wouldn't have used the electric trim to bring the plane all the way back to in-trim? Or did they? I'm confused by that. Also why they wouldn't have hit the cutouts again right after releasing the electric trim.

Thank you very much!

I think part of the problem and possible answer to the "why didn't it help" question is the badly written airworthiness directive that resulted from the Lion Air crash (see p. 4):
Airworthiness Directive AD 2018-23-51

It first says in capital letters (line 3) to set the stabilizer trim switches to "CUTOUT" and half-way down the AD repeats that instruction and adds that the switches have to stay in "CUTOUT" position for the remainder of the flight.

At the very end of the AD you will find what should have been said at the beginning, as it conflicts with the stay in "CUTOUT" position for the remainder of the flight instruction given earlier: "Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT."

Badly written AD that may have contributed to many people losing their lives. :(

Pilot error is the most obvious possibility.

Then there was AA 587. There the then undocumented super sensitive rudder in the air on the A300 combined with aggressive maneuver training of AA lead to the crash. It has very similar characteristics to the MAX roll out.