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Boeing again pt2. 14

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The plane provided direct physical feedback of the trim condition. That's peak performance in human factors.

One cannot provide any better interface than that.

Helen Keller and Stevie Wonder could have handled the trim problem.

But the problem of training that brought down PIA 8303 remains.

I looked back and found, Alistair, that your first post here was about Lion Air 610 and not once before you added ET-302 did you want the 737 MAX grounded.

I have no interest in 20/20 hindsight and how Boeing should have known better from an expert who clearly did not.

Of course neither did ALPA, nor the pilots of 737s worldwide. 10,000 votes said that what happened was a CRM problem. Then comes ET-302 and it turns out CRM once again is front and center. MCAS was the fuse, but the bomb was the training and selection process.

If the MAX MCAS was on AF447 it would have forced the nose down against the pilots holding the nose up, though hindsight wasn't required to see that triple redundancy was insufficient when Airbus KNEW the airspeed sensors were faulty and saved money by not only selecting the cheaper malfunctioning design, but failing to send notice to pilots that there was a defective design and not emphasizing in training how to handle the problem. But Airbus provides no physical feedback of the trim condition, not even feedback of what the other pilot is doing.

So, why only Boeing in the cross hairs? It cannot about safety.
 
It think it was when I joined.

A second fatal accident with the same root cause inside under a year so soon after certification yes I would expect the type to be grounded.


If there was a similar pattern on the A220 I would expect it to be grounded. We are still having pretty major updates regularly.
 
Dave, Quote; The plane provided direct physical feedback of the trim condition. That's peak performance in human factors.
By diving into the ground.
Boeing was completely blameless for initially hiding a new system from the pilots to save on training costs?
That was followed up by ineffective training.
Unfortunately the long term costs exceeded the short term savings. (By millions of dollars and hundreds of lives)
So, Dave, do you work for Boeing directly or for a contract PR firm?

(3DDave: This member limits who may view their full profile.)
 
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3D Dave - You don't give up do you?

So according to you all boeings current problems relate to two pilots who made a set of mistakes. I will accept they could have done a bit better, but when everyone got over the issues they found a whole bunch of reasons why. Ethiopian Air also got in first with the narrative about them having (mainly) followed the required new procedure.

In recent posts there are some issues which I will challenge you on:
Post 72 "MCAS was designed to offset with a slight decrease in effective elevator ability." errr, MCAS added 4 degrees every time it went off, overloading the baility of the elevatros to counter it. Hardly slight decrease.

The first crew to experience this was only really saved by the actions of an experienced third pilot in the jump seat who could see things at a higher level without being bombarded by alarms and stick shakers and clearly differences in one side of the cockpit to the other. They got lucky, but had no idea why the plane did what it did.

Post 74 "Alistair - the required procedure for the last 30 years was to cut off both switches rather than to take time to diagnose whether it was a failure in the automatics or the wiring in the control column. That was the training."

It was also dependant on this being the only issue going off and critically, before the MAX, pulling back on the control column neutralised the trim input commands. On the MAX it had no effect.

Post 76 "At the time of ET-302 everything necessary to adapt to the failure of the AoA vane was published in what would have been obvious terms to anyone who read it."

I've had this out before that the AD was, IMHO, very poorly written, provided very little information on what had happened and left a few things as open to interpretation, especially that trim switches "can be used" (not MUST) and also that "manual" operation of the trim, i.e. turning the trim wheel could be used. Also no mention that adding even 5 degrees of flap would be enough to stop it happening or even (?) changing the FCC from one side to the other - I don't actually know if that was or is feasible, but if it was it's a good plan B or C.

So the points are:
Was the fact that the larger Max stabilisers compared to previous versions which could not be countered by use of elevator alone the fault of the pilots or Boeing?
Was the fact that the trim could no longer be prevented from working by pulling back on the control column as happened in previous version the fault of the pilots or Boeing? (Note the AD mentioned nothing about this function changing)
Was the fact that adjusting the trim manually was no longer physically possible using a smaller wheel the fault of the pilots or Boeing
Was the fact that Boeing had got authorisation for this change based on a smaller angle change and also based on the now discredited memory actions occurring after a mere three seconds the fault of the pilots or Boeing?
Was the fact that no one had the ability to simulate this event even in the MAX Sims the fault of the pilots or Boeing?

I know what my answers are.

Anyway I can see you're now into whataboutery about failures in other airplanes and their makers and I very much doubt any of this will change your view, but I needed to write it down so I can stop thinking about it. At the end of the day the plane was grounded, took a long time to come back to life and Boeing may have been fatally wounded in the civil aviation market segment by the failings of the design of the Max and all our discussions are mere words in the wind.
 
His view is not uncommon in people none American or linked to Boeing directly.

It's a cult following of pilots, cabin crew and technicians. They only know the 737.

To be honest my peers including myself are not great fans of the A320 type either.

The E195 I am told is a great machine to work on.

I only know two people who flown all 4 including the MAX for Norwiegen

One prefers the E195 because it has a yoke the other the A220 because of the stick and power leavers move. I thought the E195 levers did move...
 
Littleinch -

Why do you care about Boeing in the slightest? What makes the story of Boeing so riveting when GA has been killing as many people every year for decades in the US, when the same government that owned ET-302 killed 300,000 to 500,000 Ethiopians, when Airbus has had other instances that are engineering and ethically far worse?

As expected.

No concrete indication that would make them say "OK, that makes up for it."


I'd go through the technical errors in your response but the response boils down to - after Lion Air everyone had the chance to evaluate based on what MCAS did and why MCAS did it regardless of this "they are children" concept that the AD should include every possible cause for trim runaway. It failed to include mice chewing through insulation, for example. Should there be a "mice-chewed insulation" procedure or is dealing with the symptom regardless of cause a better way to manage. Do you use a different tourniquet for a deep leg laceration from a knife than from a chainsaw? Or does one look at the what needs to be dealt with right-now and figure out what to do when on the ground?

Boeing was wounded by a press that accepted as truth a misrepresentation by those who benefited from the misrepresentation. This has become common with the reporting of events. I cannot entirely fault the media for this - it's those who are looking for information that backs their beliefs, no matter how incorrect those beliefs are, and don't look at the underlying information that drive the responses.

I wonder how it would be different if the CEO of Boeing had said "That cannot be true, the procedure, if followed, was sufficient" instead of saying "We are solely to blame." Go line by line through the FDR and compare with the AD. See that it diverges step 1 and gets worse from there.

Somewhere in Boeing is a systems engineering group that did this. Shall we find them and drag them to the wall? Would that be enough? Certainly the C-suite and the board, right?

I say after a product has a notable defect that has a work-around, then it is the sole responsibility of the user if that work-around has been demonstrated to be sufficient, as the first Lion Air flight did. The fault tree is really short - if the AoA goes south then use the AD and refer to the report that generated the AD; if they chose not to follow the AD or why it was written, the plane crashes. Up to the owner/operator to decide if that's acceptable, just like they do for all the other procedures that will end in a crash when they aren't followed.
 
By diving into the ground.
Boeing was completely blameless for initially hiding a new system from the pilots to save on training costs?
That was followed up by ineffective training.
Unfortunately the long term costs exceeded the short term savings. (By millions of dollars and hundreds of lives)
So, Dave, do you work for Boeing directly or for a contract PR firm?

(3DDave: This member limits who may view their full profile.)
Boeing didn't withhold the training about it because they didn't know about this interaction. They also don't train on other flight control systems that the pilots make no direct inputs into. MCAS has no user serviceable parts, there isn't anything that pilots can do to influence it beyond the trim runaway procedure, which they are already supposed to be trained in. Once the interaction was exposed there wasn't anything that Boeing could influence - it's up to the various FAA/CAA organization and the owners, operators, Chief Pilots, and line pilots who are responsible for determining if they have the training required and to not fly if they feel they do not.

The implication is that Boeing knew how incompetent the pilots were, in spite of evidence that pilots without any further information had handled the trim runaway as specified in the existing training and that a newbie to piloting had not. So they emphasized the trim runaway procedure and this was accepted by the various FAA/CAA organization and the owners, operators, Chief Pilots, and line pilots, including Alistair, as a temporary mitigation while a software correction was made. ET-302 planted before that software was finished and could be incorporated.

Diving into the ground was because the ET-302 crew re-enabled the electric trim and without using the thumb switch to return the plane to trim; the opposite of the procedure; another of the opposite to procedure they managed to squeeze in.
 
It think it was when I joined.

A second fatal accident with the same root cause inside under a year so soon after certification yes I would expect the type to be grounded.

If there was a similar pattern on the A220 I would expect it to be grounded. We are still having pretty major updates regularly.
You didn't suggest grounding prior to the "pattern." You don't get to say there was a problem with Boeing when you have the exact same problem.

The A220 has engine life problems. I suppose lack of testing led to the underperforming engine selection

Tell me about the flawless procedures Airbus uses in their design and how Bombardier did a great job of selecting suppliers.
 
It doesn't matter who the supplier is - Airbus had final approval. Clearly Airbus is not monitoring their suppliers of critical components closely.
 
There seems to be a preference for the leap engine on the neo.

And as the max deliveries are so low it's working out well for everyone.

Per say it's not the engine life that's an issue it is MRO capacity to turn them around.

They seem to have defined the maintenance life safely. It's more economic than anything else.
 
Not until they had mid-air engine failures with one aircraft having both finally die on the ground and unable to leave the runway.

Thankfully it was in the hands of American pilots.

Still, Airbus went with a design that has unsuitable engines that have endangered passengers, an engine that appears to have a fundamental design error that would have been caught if the money had been spent on development testing. More critical, Airbus didn't spend money on qualifying a second engine, so all their customers stand a good chance of life problems leading to emergency diversions.

The term is "Per se." It is Latin for "Of itself" so the sentence reads "Of itself it is not ..." What is "itself" referring to in that sentence?

Too bad for Airbus, it looks like the Boeing strike is just about over and Boeing can ramp up to building more 737s each month than A220s get built in a year. If their new CEO is effective and gets Boeing up to proper speed, they should easily be able to tear into the Airbus backlog.
 
This will get more interesting when China gets it new passenger aircraft certified...
 
Which dual shut down on the runway of an A220 are you on about?.

The one I know about are definitely not American. But there was definitely a Boeing pilot involved.

Max uses leap engines which are one of the options on the Neo.

The engine choice or lack of it on the A220 was certified before Airbus took the c series. Per say Airbus had no choice or input.
 
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Airbus chose to not issue a grounding order until the issue was corrected and failed to perform due diligence before putting their name on the product.

They are currently produced in an Airbus factory; how is that possible?
 
Unreliable engines may cause a pilot to panic and do the wrong thing.

Losing an engine is far more consequential than unreliable airspeed from a mis-adjusted AoA sensor and you have repeatedly maintained that training is not ever to be relied upon, so engine-out training cannot be a defense.

Since there was no other response I will take it you 100% agree that Airbus failed to perform due diligence and continued the production of a faulty product.
 
Loss of an engine on a pref A certified aircraft is not worthy of panic especially in a jet.

Unreliable airspeed is a collosal PIA sim session.
 
Engine shutdown in flight
isn't even a priority procedure.
 

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Seems Boeing is looking to sell Jeppesen

I really hope they sell it to someone that doesn't ruin it or it's products.
 

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