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Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

bbc.co.uk

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Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#151

Post by woofcat »

VBprogrammer wrote: post #73
mhandley wrote: post #7

Will be interesting to see the details when the report is actually public. It does sound like the scenario that Mentourpilot explored in the simulator is close to what happened, namely: Bad AoA probe causes MCAS to trim down, and also to indicate IAS disagree. Pilots increase throttle as per non-normal checklist to reduce the risk of stalling due to unreliable airspeed. Pilots disable electric stabilizer trim, as per…

The official report will make for interesting reading. The speculation over the last few days is starting to fill in some questions I've had: - Why didn't the pilots identify the issue as MCAS malfunction and follow the guidence? They did and it didn't work for some reason. Possibly because of the air loads on the stabilizer. - Why did the AoA sensor on a new aircraft fail? Suspected bird strike.

- They did and it didn't work for some reason. Possibly because of the air loads on the stabilizer.

Has the CVR transcript been released? I can't find any source on the procedures taken in the cockpit prior to the crash.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#152

Post by jki275 »

dis-sys wrote: post #140
jki275 wrote: post #128

Earlier quoted context omitted.

The FAA did ground the 737 Max.

FAA defended 737 Max to the very last minute, FAA is nothing else but a cheap tool for big corporations like Boeing.

The last minute when they grounded them?

I don't recall them "defending" anything, anyway, they simply held off grounding them until they got a little bit of data to back it up.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#153

Post by markmm »

hombre_fatal wrote: post #31
henrygrew wrote: post #3

Earlier quoted context omitted.

You don't belong in this community

Better for a troll to see their post casually ignored than to receive exactly what they want.

True, replying just gives the attention they seek

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#154

Post by peteradio »

VBprogrammer wrote: post #73
mhandley wrote: post #7

Will be interesting to see the details when the report is actually public. It does sound like the scenario that Mentourpilot explored in the simulator is close to what happened, namely: Bad AoA probe causes MCAS to trim down, and also to indicate IAS disagree. Pilots increase throttle as per non-normal checklist to reduce the risk of stalling due to unreliable airspeed. Pilots disable electric stabilizer trim, as per…

The official report will make for interesting reading. The speculation over the last few days is starting to fill in some questions I've had: - Why didn't the pilots identify the issue as MCAS malfunction and follow the guidence? They did and it didn't work for some reason. Possibly because of the air loads on the stabilizer. - Why did the AoA sensor on a new aircraft fail? Suspected bird strike.

Why is nobody looking at the manufacturer of the sensor?

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#155

Post by CaptainZapp »

SmellyGeekBoy wrote: post #144
sokoloff wrote: post #137

Earlier quoted context omitted.

Pilot error is the leading cause of airplane crashes. If someone offers you an even money wager that pays you if the next crash will have pilot error as a significant cause, take the wager. I am at least twice as likely to kill my airplane than my airplane is to kill me.

How many accidents blamed on "pilot error" are a result of the pilot not being given enough information to make the right decision, or given the wrong information? I'm not saying that pilots are completely faultless but if they're making mistakes we should look to improve the systems and procedures that allow them to make the right decisions, not start pointing fingers.

I'd wager that pilots, like any other professionals, make mistakes all the time.

This, however, is mitigated by a regulatory, technological and cultural safety net, which usually corrects such mistakes.

For example: There's an important cultural understanding that pilots admit safety relevant issues, even if they made a mistake in the process and not getting punished for it. The effect is that all involved entities learn from that and correct it in the future.

When something really bad happens pilot error is mostly part of the puzzle, but the bad outcome is a sequence of problems, which lead to catastrophy.

A great example is the worst disaster in civil aviation history ever[1], which ultimately was triggered by the error of a very experienced pilot. But there were a lot of small puzzle pieces, which needed to fall into place for this catastrophy to happen.

[1] https://en.wikipedia.org/wiki/Tenerife_airport_disaster

edit : spello

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#156

Post by VBprogrammer »

thg wrote: post #66
milgrim wrote: post #56

Earlier quoted context omitted.

I just sounds like nobody really thought about the consequences of MCAS triggering due to faulty AOA sensor input. There should be a dedicated switch to disable MCAS without completely disabling the electric trim motors.

> I just sounds like nobody really thought about the consequences of MCAS triggering due to faulty AOA sensor input. They did know at least two years before the first crash and decided to not do anything about it. https://www.reuters.com/article/us-ethiopia-airplane-regulat...

That article is terrible. It's a complete mischaracterisation of what it's sources actually said wrapped up in an attempt to make it relevant to the current MCAS drama.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#158

Post by simion314 »

agmiller wrote: post #136
CaptainZapp wrote: post #122

Earlier quoted context omitted.

Totally agree. Some of the sentiments expressed here was borderline racist. (badly trained, overworked cluelless third world pilots not even capable to follow a checklist). One of the worst smear jobs was actually by the New York Times accusing the captain of the Ethiopian plane not having trained in a 787-MAX simulator. Hello? Wasn't that the whole sales pitch that the plane requires no training at all for certified…

Pilot error is always assumed for pilots of all races. The French pilot who was allegedly responsible for crashing an Airbus during a flyover for an air show fought decades for clearing his name. He also claimed that the system had "artificial stupidity", that was the time when pilots first had the fun of encountering the many Airbus "flight laws".

But in this case the pilots and airlines were accused to be a lower tier then the american pilots. So on top of the regular accusations if this would have been an american airplane the third world country accusations were added on top as an extra.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#159

Post by matt4077 »

swiley wrote: post #127
CaptainZapp wrote: post #122

Earlier quoted context omitted.

Totally agree. Some of the sentiments expressed here was borderline racist. (badly trained, overworked cluelless third world pilots not even capable to follow a checklist). One of the worst smear jobs was actually by the New York Times accusing the captain of the Ethiopian plane not having trained in a 787-MAX simulator. Hello? Wasn't that the whole sales pitch that the plane requires no training at all for certified…

You really shouldn’t ever trust the NYT. They haven’t been trustworthy for a while.

Their report merely states that a simulator was available, and that the crew did not train it it. It even includes the fact that Boeing did not consider such training necessary.

How is it untrustworthy to report these uncontested facts? You are drawing a conclusion that the article does not make, namely that the lack of simulator use was the singular cause of the accident.

It takes some gall to accuse the Times of a false conclusion that happens entirely in your head.

Re: Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

#160

Post by Shank »

alkonaut wrote: post #145
mhandley wrote: post #7

Will be interesting to see the details when the report is actually public. It does sound like the scenario that Mentourpilot explored in the simulator is close to what happened, namely: Bad AoA probe causes MCAS to trim down, and also to indicate IAS disagree. Pilots increase throttle as per non-normal checklist to reduce the risk of stalling due to unreliable airspeed. Pilots disable electric stabilizer trim, as per…

I'm an armchair non-expert at best: but shouldn't planes always be controllable by the column so long as the plane is mechanically OK? I.e. max power + pull stick should always just take the plane up, regardless of any amount of misconfiguration such as being out-of-trim etc? Isn't that a reasonable expectation? That is: a pilot in panic at low altitude should never be required to do anything more than he basically c…

> but shouldn't planes always be controllable by the column so long as the plane is mechanically OK?

The problem is that you can easily exceed the aircraft flight specifications if you enable unlimited control. If you pull the stick back at max power you can seriously risk the creation of a stall, which is why MCAS exists in the first place. The whole goal Boeing had was to create a safe plane by letting software ensure it was always flying within the safe envelope for mechanical stress.

> That is: a pilot in panic at low altitude should never be required to do anything more than he basically can with hands on throttle and stick, to avoid disaster?

You would hope this, but what makes the determination that the pilot is at a low altitude? The altimeter tells you where you are in relation to sea level, not the nearest distance to terrain. You could be 10,000 feet above sea level but only 1,000 above a mountain. There's a lot of sensor data you'd have to take into account if you were to try to enable a higher degree of control based on how safe/dangerous it is to give that control.

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