Boeing Boeing 737 Max MCAS System

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You did I thought. I'm saying AP off is part of a "typically normal flight regime". You seemed to disagree.
The point isn't the frequency of it's use. The point is it's used for a very specific circumstance.

This whole point is to counter the position that the plane is "unstable" and requires mcas to maintain stability.

it's much worse than that.

mcas is to circumvent a new type certificate because that would make the plane difficult to sell.

That's why hundreds of people died, not the least of which many being humanitarians with this latest incident.

YOU seem to make defense of this disgusting scenario by suggesting that mcas is REQUIRED. that mcas must be there and we need to figure how to make it all work.

I am saying cuck mcas and train the pilots to do what the pilots are there to do.
 
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YOU seem to make defense of this disgusting scenario by suggesting that mcas is REQUIRED. that mcas must be there and we need to figure how to make it all work.
If that's what you gather from my posts I know you haven't read this thread in it's entirety. Or even understood my recent posts. In any case let's leave it at that. We're not really adding anything to the conversation.
 
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An interesting read, unfortunately it doesn't bode well for Boeing. Much of what we've assumed is fairly accurate, regarding cost cutting, managerial and certification pressures, competition, pushing an old airframe, MCAS in effect a sort of hack pushing an aging platform too far.

Some quotes:

Boeing’s 737 Max: 1960s Design, 1990s Computing Power and Paper Manuals

By 2011, Boeing executives were starting to question whether the 737 design had run its course. The company wanted to create an entirely new single-aisle jet. Then Boeing’s rival Airbus added a new fuel-efficient engine to its line of single-aisle planes, the A320, and Boeing quickly decided to update the jet again.

“We all rolled our eyes. The idea that, ‘Here we go. The 737 again,’” said Mr. Ludtke, the former 737 Max cockpit designer who spent 19 years at Boeing.

“Nobody was quite perhaps willing to say it was unsafe, but we really felt like the limits were being bumped up against,” he added.

Some engineers were frustrated they would have to again spend years updating the same jet, taking care to limit any changes, instead of starting fresh and incorporating significant technological advances, the current and former engineers and pilots said.
When engineers did make changes, it sometimes created knock-on effects for how the plane handled, forcing Boeing to get creative.
The larger size and new location of the engines gave the Max the tendency to tilt up during certain flight maneuvers, potentially to a dangerous angle.

To compensate, Boeing engineers created the automated anti-stall system, called MCAS, that pushed the jet’s nose down if it was lifting too high.
A second electronic system found on other Boeing jets also alerts pilots to unusual or hazardous situations during flight and lays out recommended steps to resolve them.

On 737s, a light typically indicates the problem and pilots have to flip through their paper manuals to find next steps. In the doomed Indonesia flight, as the Lion Air pilots struggled with MCAS for control, the pilots consulted the manual moments before the jet plummeted into the Java Sea, killing all 189 people aboard.
https://www.nytimes.com/2019/04/08/business/boeing-737-max-.html
 
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NYTimes - "The larger size and new location of the engines gave the Max the tendency to tilt up during certain flight maneuvers, potentially to a dangerous angle."

It's this part that is misleading and imo an insult to pilots and washes over what is imo the "crux" of the issue. It helps justify mcas, for what appears to be reasonable grounds.

Pilots would not maneuver the plane in such a way as to unnecessarily reach a dangerous AoA, ever.

Ceteris parabis, it is IF they flew the max version (without mcas active) the same as the previous version then it could POTENTIALLY reach dangerous aoa . (ergo flies different to a remarkable enough degree as to require new training new type certificate as per FAA rules)

Trained for the plane or not a pilot would never do such a thing, that's just crazy; the pilot, or even someone who's merely played a flying game lol would push the yoke forward just a bit and or reduce thrust a bit until the plane is at the desired pitch. Then maybe trim it to that and carry on.

A pilot doesn't NEED an automated process to do this maneuver; the FAA does though, in order to give boeing a pass on this clearly new aircraft.

no justification for mcas beyond boeings financial concerns. FAA should be held accountable equally imo.
 
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NYTimes - "The larger size and new location of the engines gave the Max the tendency to tilt up during certain flight maneuvers, potentially to a dangerous angle."

It's this part that is misleading and imo an insult to pilots and washes over what is imo the "crux" of the issue. It helps justify mcas, for what appears to be reasonable grounds.

Pilots would not maneuver the plane in such a way as to unnecessarily reach a dangerous AoA, ever.

Ceteris parabis, it is IF they flew the max version (without mcas active) the same as the previous version then it could POTENTIALLY reach dangerous aoa . (ergo flies different to a remarkable enough degree as to require new training new type certificate as per FAA rules)

Trained for the plane or not a pilot would never do such a thing, that's just crazy; the pilot, or even someone who's merely played a flying game lol would push the yoke forward just a bit and or reduce thrust a bit until the plane is at the desired pitch. Then maybe trim it to that and carry on.

A pilot doesn't NEED an automated process to do this maneuver; the FAA does though, in order to give boeing a pass on this clearly new aircraft.

no justification for mcas beyond boeings financial concerns. FAA should be held accountable equally imo.
What you're not acknowledging is that this fix (MCAS) was to solve fundamental aerodynamic deficiencies created by pushing an aging airframe too far with larger engines. This article shows such a concern was legitimate and expressed from the engineers themselves. It's not solved by simply certifying in a new class with additional training.
 
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What you're not acknowledging is that this fix (MCAS) was to solve fundamental aerodynamic deficiencies created by pushing an aging airframe too far with larger engines. This article shows such a concern was legitimate and expressed from the engineers themselves. It's not solved by simply certifying in a new class with additional training.
oh, okay.
 

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https://spectrum.ieee.org/aerospace/aviation/how-the-boeing-737-max-disaster-looks-to-a-software-developer

I am impressed by this article. It is a long read, but very informative and insightful IMO.
I worked at a competitor and only on military airplanes, so I can't vouch for the Boeing non-military flight control engineers. IMHO, this article's characterization of the flight control software engineers knowledge is completely wrong. I think they would have designed, programmed, and tested redundant systems and fault analysis for decades. They live and breath that. At least that was true of the people I worked with.
 

nsaspook

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"So Boeing produced a dynamically unstable airframe, the 737 Max"

Everything I've read about the 737 Max says this is not true. No, the 737 MAX is not aerodynamically unstable in any part of its flight envelope.
It was certified stable, in the previous vid of that "series" he says and shows this and gives the FAA regulation number.

Of all the various vids I've seen on the incident; his by far are most accurate and well said.

I time stamped the vid below to where Juan explicitly states the 737 max flies "normal" without mcas.

 
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It was certified stable
Yes. I agree that statements that the 737 MAX is "unstable" without MCAS are not justified.

Juan explicitly states the 737 max flies "normal" without mcas
"Normal" means the pilot can control the plane. Yes, that's true. But "normal" is not the same as "feels similar enough to previous 737 models to allow pilots that are type certified in the 737 to fly it without additional training". The latter is what MCAS was intended to address.
 
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Yes. I agree that statements that the 737 MAX is "unstable" without MCAS are not justified.



"Normal" means the pilot can control the plane. Yes, that's true. But "normal" is not the same as "feels similar enough to previous 737 models to allow pilots that are type certified in the 737 to fly it without additional training". The latter is what MCAS was intended to address.
You're just restating facts; am not sure you're saying anything new or addressing anything specific.

Just being correct is all....I see.
 

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