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"Boeing" is not a cause. Things like their safety culture can be a cause, or lack of good process control can be a cause. The reason why Boeing is catching a lo

by bumby 2y ago

"Boeing" is not a cause. Things like their safety culture can be a cause, or lack of good process control can be a cause. The reason why Boeing is catching a lot of flack is because they deviated substantially from best practices. This is related to your other comment so I'll just respond here. There is a general hierarchy when it comes to controlling hazards (remember, Boeing already identified MCAS as hazardous): remove the hazard, engineering controls, administrative controls, and PPE. We can apply a little thought experiment to see the gaps in what you're advocating when it comes to the MCAS issue. (Admittedly, this is contrived to just illustrate the point within the confines of a forum reply). 1) Remove the hazard: They could have redesigned the airframe to adjust the center-of-gravity to remove the stall issue that MCAS was developed in the first place. Why didn't Boeing do this? Because of cost and schedule pressure to have a new plane ready, after threats that American Airlines would take their business elsewhere. 2) Engineering controls: MCAS was an engineering control, but an incomplete one. Because MCAS was listed as "hazardous" in the hazard analysis it required redundant sensors. Why didn't they put on redundant sensors as the default? I can only speculate, but considering they were sold as optional, profit motive seems likely. (This also ignores the fact that MCAS should have been categorized as 'catastrophic' meaning they didn't fully understand the impacts of their system) 3) Administative controls: this was the training piece that you're hanging your hat on. This has multiple problems. For one, even though MCAS changed the handling dynamics of the airframe, Boeing pushed hard to reuse the same certification to avoid additional pilot training. Again, this was a business decision to make the airframe more competitive. Secondly, administrative controls are an inherently weak because of human factors. There's a lot that can go wrong if your plan is to have humans follow an administatrive procedure. You claim "it's not hard". Sorry, this is just a bad mindset. Usually when I hear people say things like "it's not hard" or "all you've gotta do" when they're talking about complex systems, it indicates they take an overly simplified mental model. In this case, you may be ignoring the chaos in the cockpit, the fact that the plane has handling characteristics different from what the pilots were trained on, human factors related to stab trim force at speed, conflicting or confusing information (like why the MCAS comes on at changing timeframes, time criticality, etc. Having adminstrative controls as your main mitigation is bad practice, and setting the system up for failure. 4) PPE: this isn't particularly relevant to this case, but a silly example of PPE control is giving everyone parachutes and helmets in case things went south. You can obviously see PPE is an absurd control. But your main point is that the main control should be administrative, which is the next worst option. Boeing ignored good safety practice to pursue profit. So they probably deserve some of the heat they are getting.

WalterBright 2y ago
"redesigned the airframe" means designing an Entirely New Airplane. Boeing didn't do this because designing an entirely new airplane would have been: 1. an absolutely enormous cost, like a couple orders of magnitude more 2. several years of delay 3. pilots would have to be completely retrained 4. the airlines liked the 737 very much 5. mechanics would have to be retrained 6. the inherent risk of a new, untried airframe There was nothing at all inherently wrong with the concept of the MCAS system, despite what ignorant journalists wrote. What was wrong with it was it was not dual path, had too much authority, and would not back off when the pilot countermanded it. These problems have been corrected. Pilot training - there have been many, many airplane crashes because pilots trained to fly X and Y did the Y thing when flying X. The aviation industry is very well aware of this. Boeing has been working at least since 1980 (and likely much earlier) to make diverse airplane types fly the same way from the pilot's point of view. This is because it is safer. And yes, it does make pilot training cheaper. Win-win. > You claim "it's not hard". Sorry, this is just a bad mindset. Yet it's true. Read about the first MCAS incident, the one that didn't crash. There were 3 pilots in the cockpit, one of which was deadheading. The airplane did some porpoising while the pilot/copilot would bring the trim back to normal, then the MCAS would turn on, putting it into a dive. Then, the deadheading pilot simply reached forward and turned off the stab trim. And the day was saved. I've seen your points many times. They are all congruent with what journalists write about the MAX. Next time you read one of those articles, I recommend you google the author to see what their background is. I have done so, and each time the journalist has no engineering degree, no aeronautical training, no pilot training, no experience with airline operations, and no business experience. You can also google my experience. I have a degree in mechanical engineering with a minor in aeronautics from Caltech. I worked for Boeing for 3 years on the 757 stabilizer trim design. (It is not identical to the 737 stab trim design, but is close enough for me to understand it.) At one point I knew everything there was to know about the 757 trim system. A couple dozen feet away was the cockpit design group, and we had many very interesting discussions about cockpit user interface design. I'm not a pilot myself, but other engineers at Boeing were, and they'd take me up flying for fun. Naturally, airplanes were all we talked about. My brother and cousin are pilots, my cousin was a lifer engineer at Boeing, my dad flew for the AF for decades in all kinds of aircraft, with an engineering degree from MIT. I inherited his aviation library of about a thousand books :-/ Naturally, airplanes were a constant topic in our family. I've talked with two working 737 pilots about the MAX crashes. I've read the official government documents on the MAX crashes, and the Emergency Airworthiness Directive. That's what I "hang my hat" on. So go ahead, tell me I don't know what I'm talking about. But before you do, please look up the credentials of the journalists you're getting your information from. P.S. "Aviation Week" magazine has done some decent reporting. P.P.S. Amazingly, the "Aviation Disasters" TV documentary is fairly decent in its analysis of various accidents, lacking the histrionics of other treatments. But it's rather shallow, considering it's a 40 minute show.

by bumby 2y ago

WalterBright 2y ago

"redesigned the airframe" means designing an Entirely New Airplane. Boeing didn't do this because designing an entirely new airplane would have been: 1. an absolutely enormous cost, like a couple orders of magnitude more 2. several years of delay 3. pilots would have to be completely retrained 4. the airlines liked the 737 very much 5. mechanics would have to be retrained 6. the inherent risk of a new, untried airframe There was nothing at all inherently wrong with the concept of the MCAS system, despite what ignorant journalists wrote. What was wrong with it was it was not dual path, had too much authority, and would not back off when the pilot countermanded it. These problems have been corrected. Pilot training - there have been many, many airplane crashes because pilots trained to fly X and Y did the Y thing when flying X. The aviation industry is very well aware of this. Boeing has been working at least since 1980 (and likely much earlier) to make diverse airplane types fly the same way from the pilot's point of view. This is because it is safer. And yes, it does make pilot training cheaper. Win-win. > You claim "it's not hard". Sorry, this is just a bad mindset. Yet it's true. Read about the first MCAS incident, the one that didn't crash. There were 3 pilots in the cockpit, one of which was deadheading. The airplane did some porpoising while the pilot/copilot would bring the trim back to normal, then the MCAS would turn on, putting it into a dive. Then, the deadheading pilot simply reached forward and turned off the stab trim. And the day was saved. I've seen your points many times. They are all congruent with what journalists write about the MAX. Next time you read one of those articles, I recommend you google the author to see what their background is. I have done so, and each time the journalist has no engineering degree, no aeronautical training, no pilot training, no experience with airline operations, and no business experience. You can also google my experience. I have a degree in mechanical engineering with a minor in aeronautics from Caltech. I worked for Boeing for 3 years on the 757 stabilizer trim design. (It is not identical to the 737 stab trim design, but is close enough for me to understand it.) At one point I knew everything there was to know about the 757 trim system. A couple dozen feet away was the cockpit design group, and we had many very interesting discussions about cockpit user interface design. I'm not a pilot myself, but other engineers at Boeing were, and they'd take me up flying for fun. Naturally, airplanes were all we talked about. My brother and cousin are pilots, my cousin was a lifer engineer at Boeing, my dad flew for the AF for decades in all kinds of aircraft, with an engineering degree from MIT. I inherited his aviation library of about a thousand books :-/ Naturally, airplanes were a constant topic in our family. I've talked with two working 737 pilots about the MAX crashes. I've read the official government documents on the MAX crashes, and the Emergency Airworthiness Directive. That's what I "hang my hat" on. So go ahead, tell me I don't know what I'm talking about. But before you do, please look up the credentials of the journalists you're getting your information from. P.S. "Aviation Week" magazine has done some decent reporting. P.P.S. Amazingly, the "Aviation Disasters" TV documentary is fairly decent in its analysis of various accidents, lacking the histrionics of other treatments. But it's rather shallow, considering it's a 40 minute show.