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Boeing 737 Max 8
- Thread starter nobbie48
- Start date
Greedy c***suckers. NY times article says Boeing sold AOA indicator and disagree light (to indicate the AoA sensors had different readings) as optional extras. The pilots have a hard time figuring out what the plane is actually doing without feedback. Apparently disagree light will now come standard. I think boeing will have a hell of a time getting max 8's approved unless they get a third AOA sensor and appropriate controls to let the pilots know what reading two sensors agree on.
Another problem i have seen mentioned is that mcas can dial in 2.5 degrees of trim. Once disabled, pilots have to crank that back out by hand which takes quite a while (apparently 6000+ feet of elevation if the pilot can't keep something like 90 kg of pressure on the stick). Thats a huge problem. I think boeing will also need to add mcas defeat that leaves jackscrew electrical connected. That brings back brian p's problem of an unpredictable, unstable aircraft which is better than one that is self-crashing but still useless for passenger duty.
www.nytimes.com
EDIT:
Blancolirio released a new video with a detailed description of MCAS. He is a 777 pilot so it's not as good as a discussion from a Boeing engineer but I doubt we'll see that if they value their career.
Another problem i have seen mentioned is that mcas can dial in 2.5 degrees of trim. Once disabled, pilots have to crank that back out by hand which takes quite a while (apparently 6000+ feet of elevation if the pilot can't keep something like 90 kg of pressure on the stick). Thats a huge problem. I think boeing will also need to add mcas defeat that leaves jackscrew electrical connected. That brings back brian p's problem of an unpredictable, unstable aircraft which is better than one that is self-crashing but still useless for passenger duty.
Doomed Boeing Jets Lacked 2 Safety Features That Company Sold Only as Extras (Published 2019)
Airlines had to pay more for two optional upgrades that could warn pilots about sensor malfunctions. Boeing now plans to make one of the features standard.
EDIT:
Blancolirio released a new video with a detailed description of MCAS. He is a 777 pilot so it's not as good as a discussion from a Boeing engineer but I doubt we'll see that if they value their career.
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But MCAS is not "autopilot". It's a "Maneuvering Characteristic Augmentation System". As I mentioned in an earlier response, it's entire purpose is to correct potentially problematic flyability issues....which, contrary to popular belief, is far more common than most understand.
But yes, it too should be capable of being disabled in an emergency, at least in the case of aircraft that are actually flyable without it. That said, it shouldn't need to be however, much the same as how countless other planes that use augmentation systems don't need to have them disabled.
The root problem is how it's programmed, and how it relies on a single point of data.
Evidently, it relies on a single sensor and contains no redundancy with the intent of Boeing avoiding having to classify this system as being safety-related. And that was so that they could extend the type-approval of the 737-class aircraft to this new model because the safety-related parts of the flight controls were (ostensibly) the same as the prior model.
Dunno about you but MCAS sounds to me like "gizmo that screws around with the plane's flight surfaces" which sounds to me like "safety-related".
Dunno about you but MCAS sounds to me like "gizmo that screws around with the plane's flight surfaces" which sounds to me like "safety-related".
Especially when you are manually flying the plane. I get annoyed enough when a car/computer/phone is programmed to ignore what the operator wants (vw hill hold on standard cars/microsoft almost anything/blackberry only allowing manual email setup after auto setup fails three times for example). I can only imagine the problems that causes in a plane. If i am in control, i expect to be in control. The computer can give me displays/warnings/audible alarms if it wants, but stay the bleep away from the control surfaces.
Apparently Boeing has had some engine based problems with the 787. Rolls Royce isn't looking good. Not sure where that lies at the moment. The last I read the 787 had to stay within an hours flight time of an airport. There were also start up issues with lithium batteries as well. I gather that has been resolved. Is there some sort of internal problem with Boeing?
Speed of development and profit above safety? I'm not sure whether Boeing considers that a problem or a brilliant business decision. :/
FWIW, I flew in a 787 to Japan three years ago. Obviously, during most of that flight we were more than one hour from a suitable airport.
J_F
Guest
so this is the AOA device....looks like a weather vein to me
initial reports for the Ethiopian crash are this sensor was damaged prior to the crash
how they are able to determine that after the thing plowed into the earth is curious
proposed fix is supposedly to include 2 of these things that apparently have a high failure rate
initial reports for the Ethiopian crash are this sensor was damaged prior to the crash
how they are able to determine that after the thing plowed into the earth is curious
proposed fix is supposedly to include 2 of these things that apparently have a high failure rate
The airplane already has two of those sensors, but the MCAS system only uses one of them. Both are logged in the flight data recorder, though.
The preliminary report for the Ehiopia crash is out, and I've read it. The right AOA gave a plausible reading during takeoff, but the left one fluctuated, at one point indicating >70 degree AOA, and that's the one MCAS was evidently using. Also, the pilots followed Boeing's stated procedure for dealing with a faulty trim control system, which obviously didn't work.
The preliminary report for the Ehiopia crash is out, and I've read it. The right AOA gave a plausible reading during takeoff, but the left one fluctuated, at one point indicating >70 degree AOA, and that's the one MCAS was evidently using. Also, the pilots followed Boeing's stated procedure for dealing with a faulty trim control system, which obviously didn't work.
I havent read the report yet, but one news article i read said that the mcas continued to act even after the trim cutouts were thrown. If that truly happened, Boeing may be done fer. The liabilility if the plane was actually impossible for the pilots to save is staggering.
Even a billion dollar settlement is pocket change Boeing will be fine.
Sent from my SM-G935V using Tapatalk
Sent from my SM-G935V using Tapatalk
J_F
Guest
is this where all fixed wing aircraft get the data to set off the stall warning?
I've been in small craft where the pilot is trying to grease it on landing
and the stall warning is blaring while they have a "hold my beer" look on their face
Riceburner
Well-known member
https://www.cbc.ca/radio/asithappen...nes-crash-now-he-s-taking-on-boeing-1.5084655
Wonder if a class action carries any extra weight....
Wonder if a class action carries any extra weight....
I hate lawsuits that just name everybody in the hopes that something sticks. It is beyond a prick move and should be punished severely if some parties are found to be not liable. In this case, I haven't heard of anything that Ethiopian airlines did wrong other than not ordering the "optional extra" safety features which to me is a Boeing problem, not an airline problem. Yes, it appears that the pilots switched the trim cutout back to operational which ultimately doomed the plane, but prior to that point they followed all training and procedures properly, they just seemed to be mentally overwhelmed by Boeings ineptitude.
I still think Boeings biggest problem is given the incredibly poor design of MCAS, what other design flaws are present but not yet discovered? Obviously the design/review/approval process was terribly flawed and ineffective. Proving that the Max 8 is actually safe and certifiable and should be back in the air may take years (especially in europe as that would give Airbus a huge boost).
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There are liability limits for air passengers. If those weren't in place, it would be impossible for the aviation industry to exist, particularly in the lawsuit-happy USA. Slightest incident otherwise would have lawyers filing lawsuits in every possible direction.
It boggles my mind that safety devices are optional.
Did I pick up somewhere that the airplane industry is working towards self policing?
It seems that death is just collateral damage when there are profits at stake.
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