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This is insane. One of the automated systems can malfunction and crash the plane and apparently Boeing never trained the pilots on the system.
https://interestingengineering.com/pilots-have-40-secs-to-try-to-save-737-max-8-if-autopilot-malfunctions?utm_source=Facebook&utm_medium=Article&utm_campaign=organic&utm_content=Mar27
He waited his whole damn life just to take that flight and when the plane went down he thought “HOLY SHIIITTT WERE GONNA DIE!!”
But I thought he said, “well isn’t this nice...? And isn’t it ironic, don’t you think...?
He waited his whole damn life just to take that flight and when the plane went down he thought “HOLY SHIIITTT WERE GONNA DIE!!”
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But I thought he said, “well isn’t this nice...? And isn’t it ironic, don’t you think...?
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Yeah, I really do think
I heard a pilot explain that the emergency procedure is the same as it was before this was added. Basically said if the trim is doing something you don't want, you turn it off and fly the plane yourself.
I heard a pilot explain that the emergency procedure is the same as it was before this was added. Basically said if the trim is doing something you don't want, you turn it off and fly the plane yourself.
I have a couple friends that are 737 pilots and they basically said the same thing. HOWEVER, another key point in this is that an angle of attack indicator is an "option" on the new Max's and neither of the jets that crash had them. 40 seconds is an eternity in the cockpit. https://arstechnica.com/information-technology/2019/03/boeing-sold-safety-feature-that-could-have-prevented-737-max-crashes-as-an-option/
sundance435
03-28-19, 16:21
I have a couple friends that are 737 pilots and they basically said the same thing. HOWEVER, another key point in this is that an angle of attack indicator is an "option" on the new Max's and neither of the jets that crash had them. 40 seconds is an eternity in the cockpit. https://arstechnica.com/information-technology/2019/03/boeing-sold-safety-feature-that-could-have-prevented-737-max-crashes-as-an-option/
I thought it had something to do with an extra sensor - not an AoA indicator. Most planes would have an AoA indicator. Regardless, there was something that most, if not all, of the US/North American planes had as an option that neither of the 2 crashed planes had.
This is insane. One of the automated systems can malfunction and crash the plane and apparently Boeing never trained the pilots on the system.
Dont think this is correct as a friend is a 737Max pilot and says he is fully trained and none of these "revelations" is news to him.
FromMyColdDeadHand
03-28-19, 16:50
In order to fully shut down the MCAS function that was pushing the plane into a nosedive, the pilots would have to flip the switch at their thumb, then flip two more switches elsewhere that would shut down the power to the motor the MCAS used to push the nose down. Then, the pilot would then need to turn a crank to fix any remaining problems caused by the system before they would have control of the aircraft again.
The MCAS isn't in the manual. This also isn't a run away trim- it was intermittent.
Who in the living hell of stupid engineering would wire this thing to one sensor? That guy needs to be dropped out of a 737 at 12,000 and told to learn to fly.
People can defend Boeing all you want on this, but that is 100% fail, like criminal fail. The plane would have been safer WITH OUT THE SAFETY SYSTEM. How in the living hell could you blame pilots, who were never told about the system- it ain't in the manual- that this Dues Ex Machina safety device could also doom the plane.
About as logical as having a Guillotine as a seatbelt cutter in a car in case there is an accident and you are trapped.
The MCAS isn't in the manual. This also isn't a run away trim- it was intermittent.
Who in the living hell of stupid engineering would wire this thing to one sensor? That guy needs to be dropped out of a 737 at 12,000 and told to learn to fly.
People can defend Boeing all you want on this, but that is 100% fail, like criminal fail. The plane would have been safer WITH OUT THE SAFETY SYSTEM. How in the living hell could you blame pilots, who were never told about the system- it ain't in the manual- that this Dues Ex Machina safety device could also doom the plane.
According to the 737Max pilot I know, this is not true. He speculates that some carriers, especially foreign, did not re-train 737 pilots for the 737Max.
Agreed though, the second sensor optional is stupid. His planes have both sensors.
FromMyColdDeadHand
03-28-19, 17:39
According to the 737Max pilot I know, this is not true. He speculates that some carriers, especially foreign, did not re-train 737 pilots for the 737Max.
Agreed though, the second sensor optional is stupid. His planes have both sensors.
American carriers pilots said that they had less than an hour on ipad? At best the system was reading one sensor.
There is so much noise on this.
I heard a pilot explain that the emergency procedure is the same as it was before this was added. Basically said if the trim is doing something you don't want, you turn it off and fly the plane yourself.
Yeah, this. It's not a Boeing issue, it's a training issue. A failure of the AOA sensor, either one, will let the MCAS (which is new on the MAX8 and MAX9) take over the plane. Adequately trained pilots know what to do.
Interestingly, with the LionAir flight, that same plane had done exactly the same thing that crashed it the day before with a different crew. Neither the pilot nor first officer knew what to do but their was another LionAir captain sitting in the jump seat, fortuitously just dead-heading. He reached forward for them and solved the problem....no crash. Now, two questions... 1) why didn't that first flight crew know how to solve the problem when Southwest pilots all do? and b) WTF didn't LionAir replace the faulty AOA sensor after that first event so that that same plane wouldn't have crashed less than 24 hours later?
Aviate, Navigate, Communicate in that order. I'm starting to step out of my lane here, but if your airplane pitches nose down 10 degrees and you did not ask it to, why wouldn't you shut off the systems and fly the airplane manually? BTW.. I agree that there is plenty of blame to go around here.
I won't say the new system is perfectly engineered or integrated. I dislike the lack of redundancy, I dislike the mode of failure (in process engineering a switch can be designed so when it fails it will be open or closed for example) I dislike the AOA sensors not failing out from mismatch.
But listening to a well trained pilot calmly explain the procedure to turn off the trim is the opposite of the hysterical reporting we get on the news. The procedure is the same as it has always been. If a pilot can't fix this a mechanical or electrical problem with the trim motor becomes potentially fatal. That's a pilot problem.
Yeah, this. It's not a Boeing issue, it's a training issue. A failure of the AOA sensor, either one, will let the MCAS (which is new on the MAX8 and MAX9) take over the plane. Adequately trained pilots know what to do.
Im going to disagree with you here.
Let me qualify my experience... I is a 737 pilot with time in the MAX...
This is 100% a Boeing problem and they are eating a HUGE shit sandwich over it... I will agree, to a much lesser extent, that this is also a training issue. My airlines procedures did not change after the 1st crash, but I believe they are going to slightly after this second one and the grounding.
Boeing never told anybody about this system before the Lion Air crash 5 months ago...nobody...not even maintenance...it wasnt even in the manual.
Now a second crash with all signs pointing to the same failure mode... And a ton more comes out about how the MCAS REALLY REALLY works and its not good... The thing only looked at one AOA sensor at a time(it switched every landing) so a single point failure could cause the MCAS to run when it wasnt supposed to. The MCAS also could run almost 4x the amount of trim that Boeing told the FAA it could run as well as run it multiple times until it was full nose down. So if MCAS runs because it needs to(low speed, high AOA, approaching a stall) you are at low speeds and 2.5 degrees of nose down pitch isnt a big deal... If you are at 250+ kts and the MCAS runs because of a failure, 2.5 degrees nose down trim is a SHIT TON...
The reprogramming is going to have the MCAS constantly monitor both AOA, if a single AOA fails the MCAS will deactivate, if MCAS activates once, thats it for that flight, and a few other things...
I have 100% confidence in the airplane both pre and post Ethiopian Air crash, but Boeing ****ed this one up royally. Its hard to blame a training issue on a system that Boeing never told anybody about and when they did they didnt really tell the whole story...
How did anyone at Boeing think not informing anyone would be s good idea?
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How did anyone at Boeing think not informing anyone would be s good idea?
I wonder if this might've been Boeing rushing to get the Max certified and approved as quickly as possible to compete against Airbus's Neo...and might've withheld some things that might delay the process.
sundance435
03-29-19, 08:21
I wonder if this might've been Boeing rushing to get the Max certified and approved as quickly as possible to compete against Airbus's Neo...and might've withheld some things that might delay the process.
I think that's the gist of it. They wanted, more than anything, to keep the type-certification for the legacy 737s and by all accounts, even if it was only MCAS, the plane they basically self-certified was different enough that it warranted more than 1 hour on an iPad for familiarity. I have no idea how type-certification works, so I don't know if a more robust training program would've required them to get a new certification, but that was clearly what they should've done. Regardless, the FAA was letting them do their own thing anyway, so how much of delay could there have been?
Boeing spends too much time and effort worrying about what Airbus is doing and this is the worst-case result. Build a better plane and people will buy it - the airplane market is so unpredictable that the Neos beating the Max to the market is a variable at best, not a deal-killer. As current events have demonstrated, they apparently didn't quantify the risks well enough - 2 crashes and a grounding will kill far more deals than their competitor being on the market with a similar product months ahead of them.
It's a shame - Boeing used to be an American company I admired for numerous reasons, but this has me seriously questioning their ethics. Every company has its bad moments, but you're literally risking lives in this kind of situation
Im going to disagree with you here.
Let me qualify my experience... I is a 737 pilot with time in the MAX...
This is 100% a Boeing problem and they are eating a HUGE shit sandwich over it... I will agree, to a much lesser extent, that this is also a training issue. My airlines procedures did not change after the 1st crash, but I believe they are going to slightly after this second one and the grounding.
Boeing never told anybody about this system before the Lion Air crash 5 months ago...nobody...not even maintenance...it wasnt even in the manual.
Now a second crash with all signs pointing to the same failure mode... And a ton more comes out about how the MCAS REALLY REALLY works and its not good... The thing only looked at one AOA sensor at a time(it switched every landing) so a single point failure could cause the MCAS to run when it wasnt supposed to. The MCAS also could run almost 4x the amount of trim that Boeing told the FAA it could run as well as run it multiple times until it was full nose down. So if MCAS runs because it needs to(low speed, high AOA, approaching a stall) you are at low speeds and 2.5 degrees of nose down pitch isnt a big deal... If you are at 250+ kts and the MCAS runs because of a failure, 2.5 degrees nose down trim is a SHIT TON...
The reprogramming is going to have the MCAS constantly monitor both AOA, if a single AOA fails the MCAS will deactivate, if MCAS activates once, thats it for that flight, and a few other things...
I have 100% confidence in the airplane both pre and post Ethiopian Air crash, but Boeing ****ed this one up royally. Its hard to blame a training issue on a system that Boeing never told anybody about and when they did they didnt really tell the whole story...
I’ve been flying 737s for 15 years and like RJ, I have time in the Max. What RJ said above is true, but at some point, the pilots have to the the freakin’ airplane. Everyone is pointing fingers at Boeing and they deserve that, but where is the conversation about the experience level and professional background of the pilots in these mishaps? The AE first officer had only 200 hours. What about the overall training programs (not just for the Max), policies & procedures of the airlines in question? The Lyon Air flight prior to the mishap flight seems to have had the same problem taking off out of Bali, but the crew decided to continue to Jakarta instead of returning to Bali.
737s, included the Max, are uber reliable and having any issue with the jet is extremely rare. When there is a problem, most of the time there is a procedure in the in the book. Sometimes there isn’t. When that happens, pilots have to rely on their experience/skill to get the plane safely on the ground.
Not all pilots are equal, even those with the same amount of flight time. Having flow with pilots from dozens of other countries during my time in the USAF I can tell you that the culture a pilot grows up in, as well and what country a pilot receives their flight training in has a tremendous impact on how those pilots fly (skill wise) and how those air-crews operate in terms of overall safety.
So if MCAS runs because it needs to(low speed, high AOA, approaching a stall) you are at low speeds and 2.5 degrees of nose down pitch isnt a big deal... If you are at 250+ kts and the MCAS runs because of a failure, 2.5 degrees nose down trim is a SHIT TON...
I've seen some speculation based on that most recent accident report, based on the control inputs and motion of the aircraft, that the last MCAS input was extreme enough to make it physically difficult to haul back on the stick. IIRC they were way, way over 250 kts.
So far the cliff notes I'm picking up is that the MCAS shittiness put them at an airspeed at which their manual trim efforts were not effective, but the switch to cutout MCAS from messing with the electric trim also disabled their other electric trim options. It does not sound like there was an actual deliberate option for stopping MCAS - only to prevent its signal from being acted upon.
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