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davidb

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Davidb, what are the steps when you get this MCAS problem? Do you have a few " memory items" and then isolate the system or does overriding it shut it down? Thank you for participating in this.
The scenario is triggered by the faulty AoA input. There is no specific checklist or memory items for a faulty AoA but it leads to other false indications and eventually unwanted MCAS trimming. Namely, the false AoA will eventually cause “Airspeed Unreliable” and “Runaway Trim” for which there are checklists and memory items.

We fly jets based on known pitch and power settings as well as knowing expected performance criteria. I learned to fly in a jet that had an attitude indicator that was simply a black ball with white markings. Knowing pitch and power settings was the only way to effectively fly. Nowadays, that attitude indicator is cluttered with all sorts of information and directors that is nice to have IF it is accurate. If the flight director and dynamic airspeed limitations are accurate, it negates the need to know basic pitch, power and performance criteria. However, a faulty AoA causes all the “nice to have” indications on the attitude indicator to become a bogus distraction.

Back to the scenario, everything is normal until you reach flying speed and rotate to takeoff pitch attitude. At that point you get the stick shaker as well as bogus pitch limiter, flight director and speed limiter indications. The actual speed and attitude are still accurate. The other side of the cockpit instruments are all normal. It’s quickly obvious that the aircraft is flying normally and that there is merely some indicator malfunctions. Both mishap crews got through this initial phase.

I’ll continue tomorrow...
 

plncraze

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Yes! According to the Nova episode all Flight 447 had to do, after diagnosing the problem, was pull the nose up to 5 degrees above the horizon on the peanut gyro and set 85 percent power until the pitots drained.
 

TXFlyGuy

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Yes! According to the Nova episode all Flight 447 had to do, after diagnosing the problem, was pull the nose up to 5 degrees above the horizon on the peanut gyro and set 85 percent power until the pitots drained.
On the 777, it is 2.5 degrees nose up, 88 to 92% N1. At altitude, depending on your GW.
 

plncraze

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I love it when professional pilots can recite stuff like that. I have known folks who have a lot of experience with a plane and they can tell what "the light" or "the warning message" really mean. And sometimes what it will cost to fix LOL.
 

jedi

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The pilots of Air France 447 never understood this basic concept. If they did, they would be alive today.
Ref Post #501 "We fly jets based on known pitch and power settings as well as knowing expected performance criteria."

Airline Piloting 101. You get paid $100,000 to hold the right pitch, another $100,000 for the right bank and another $100,000 for the right power. Keep the ball in the center if you want to live long enough to collect the check.

I think (but do not know if you want my opinion as to why) the pilots knew this but the training and environment was not sufficient to progress to the correlation (4th and last) level of learning. There was a failure to apply the rote learning in a timely manner.

The following is the United States of America official training position.

FAA-H-8083-9 lists six principles of learning: Readiness, Exercise, Effect, Primacy, Intensity, and Recency.
...
There are four basic levels of learning:
  • "Rote. The ability to repeat something back which was learned, but not understood."
  • "Understanding. ...
  • "Application. ...
  • "Correlation.
 
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plncraze

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With apologies to whomever I offend with this comment: I don't think 447's crew was awake enough to handle this scenario. They had a couple of minutes before 12000 feet (when recovery was impossible) and nobody in the cockpit could pull this together. There are situations where I have to play mental games with myself to keep up my attention for a few hours and I have never been over the Atlantic at 39000 feet with nothing to do. It must be stupefying. Jedi is correct in saying you are paid to do a couple of things. I knew a relief pilot for an Atlantic run. He just sat there. Ugh!
 

jedi

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........ Jedi is correct in saying you are paid to do a couple of things. I knew a relief pilot for an Atlantic run. He just sat there. Ugh!
Been there done that but I learned early on (many thanks to a good CFI) that it is never a good idea to "just sit there" when in the pilot seat.

Airline 102 When the bell or whistle goes off you have a choice to make. You can earn your pay and apply the lessons learned in Airline 101 (ref post # 506) or you can do what is required in order to "just walk off the plane".

PS: Completing the appropriate checklist MAY help accomplish your goals. If not, keep flying the plane (bank, pitch and power).

For the record: In the Air France Flight 447 incident; bank, pitch and power was not the solution in the end. That is where the "do whatever is required to walk of the plane" comes into play. It helps a lot to know what the problem is. 737 Max pilots did not understand the problem because they did not understand the system. That was the problem. Is that poor training?
 
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davidb

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Continuing from post 501...

The rotation and pull up to the initial takeoff target pitch is done with reference to the horizon (or attitude indicator if visibility is low) so all the other bogus indications aren’t yet at play. The stick shaker has a startle effect but it’s obvious you have flying airspeed. It is after establishing the initial climb that you take the flight director into your cross check and notice all the bogus indications.

The “Airspeed Unreliable” checklist is designed to help you work through determining which indicators are unreliable and if they can be restored. It now has memory items but basic airmanship is really better (initially) than fumbling through a checklist. The memory items are just actions and targets that are in the realm of basic airmanship. In the scenario, if you just fly an appropriate pitch attitude and look at all the indications it’s quickly obvious that everything is normal on the first officer’s side.

At this point of scenario (when I had it in the simulator) I transferred control to the first officer and left the flaps down with the intention of just getting vectors for a normal approach and landing. Everything is normal on the right side. Our first officers are just as qualified as our captains.

Well, as part of the scenario, the simulator instructor wanted us to experience the MCAS trimming so he vetoed my plan and made us retract the flaps and continue to a normal climb out departure.

We got the trimming. Initially it could easily be discounted as the typical speed trim we are all familiar with. If it trims to where you don’t want it, you trim it back. We do this subconsciously. It’s just a basic flying skill—we keep the airplane in trim. After it happens a couple of times, you become conscious of it. You don’t really need a “Runaway Trim” checklist or memory items to do the right thing. If something unwanted keeps happening and you have a switch to turn it off, you turn it off. We turned it off and used the trim wheel. Worked good. We played with trimming it full nose down to see if we still had elevator authority and we did (but we didn’t try it at ludicrous speed).

Ok, I have hindsight and knowledge the mishap crews did not. We all have that now. It is with this knowledge that I can say the Max can be safely operated even without the modifications.

Things working against the mishap crews are many. IMO, the most significant is not having first officers who are as qualified as captains. When unusual things happen, it’s imperative that one pilot focuses on flying the airplane, then the other pilot can focus on problem solving.
 

lear999wa

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David, thank you for the good write up.

Hopefully Boeing will be able to get the aircraft back into compliance and into into the air again.
 

Doggzilla

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I’m surprised nobody is talking about the CEO being fired and replaced with a GE vet.

The comments from former GE employees are extremely negative. The massive mismanagement at GE and loss of jobs is not exactly considered an environment that produced good leaders.

It went from most valuable stock on the market to being delisted. Definitely something that warrants vigilance.
 

plncraze

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Managerial inbreeding? They all sit on the same boards ( of directors) so they always choose from the the same group of people.
 
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PMD

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Managerial inbreeding? They all sit on the same boards ( of directors) so they always choose from the the same group of people.
This is an astute observation. It supports what I see elsewhere that companies ruled by the world of finance have ncestuous boards and management that answer to Wall Street, not product, quality, clients, employees or minority shareholders. They have no pride in what the companies produce, only what they can put in their pockets. GE is the poster child for the death of real companies.
 

Doggzilla

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That’s why Marc Benioff does so well as a CEO. His company has a $145 billion market evaluation right now.

Leaders who care attract workers who care, which attracts customers who see the employees care. And so the company performs astonishingly well.

But be warned, he is extremely political and not ashamed to talk about it. So don’t be shocked if you watch any of his interviews.

His interviews definitely get a bit spicy sometimes.
 

Doggzilla

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That can be said about Costco as well. The CEO cares and his employees care as a result.

They get paid twice as much but are 300% as efficient. Which means 50% greater efficiency per dollar spent on labor.

CEOs attract similar employees. A caring CEO attracts caring employees.
 

gtae07

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Never ending story of bad new from Boing?

Boeing 737 Max: Worker said plane 'designed by clowns'
https://www.bbc.com/news/business-51058929
Of all the quotes in the article, that's a throwaway one. You could go out to almost anyone on the production or maintenance floor, for almost any aircraft, and find no shortage of people who hold that opinion (justified or not).

Anyone who's worked on a car produced in the last 30-40 years has probably muttered something similar about the designers who put $component wherever it wasn't easy to access...
 
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