737 Max 8/9

brian4d

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Dec 3, 2007
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This was pilot error that started with training. The plane has no flaws. Just my prediction. Either way hope Boeing and crews get this worked out. IF it turns out the issue is plane related (like the early model rudder issues) this will be very bad for Boeing.
 

brian4d

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Dec 3, 2007
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High Point, NC
I'm not privy to the brand new tech on cockpits but I do do know accidents are caused buy multiple failures/pilot error. Just one sensor going bad (stuff in airplanes breaks, they have logs just for it) would/should not bring this jet down. It would be multiple problems/errors happening back to back to back. Input on the pilot control surfaces 'should' disengage the autopilot instantly and let the pilots fly. Something(s) are not right.
 

pinkytoe69

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Jan 14, 2012
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minnesota
I'm not privy to the brand new tech on cockpits but I do do know accidents are caused buy multiple failures/pilot error. Just one sensor going bad (stuff in airplanes breaks, they have logs just for it) would/should not bring this jet down. It would be multiple problems/errors happening back to back to back. Input on the pilot control surfaces 'should' disengage the autopilot instantly and let the pilots fly. Something(s) are not right.
Did you read the article?

The new tech was necessary because the modified engine placement causes the plane to pitch up.
 

Rocky

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Apr 23, 2004
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The 737s are near and dear to a good friend of mine. I have no clue if he was flying a Max 8 until they were grounded. But it sounds like the special software mods they had to introduce to aerodynamically manage the effect of the different engine isn't playing nice with the aircraft.
 

SGaynor

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Dec 6, 2006
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From what I've read the new software will override the pilot control inputs (aka, yoke, throttle) under certain conditions. The pilots weren't told of this, nor what those conditions are. I'm not a pilot, but I think that having your fly by wire suddenly not work without warning is a bad thing.

The software, known as the Maneuvering Characteristics Augmentation System (MCAS), can in some rare but dangerous situations override pilot control inputs unless it is switched off. This can interfere with pilots’ longtime training that pulling back on the control yoke raises a plane’s nose, putting the plane into a climb. That means that as a pilot tries to maneuver an airplane, the automated system may be counteracting that pilot’s inputs.

The Max uses engines that are both bigger and more fuel-efficient, and the new engines have been moved slightly forward on the wings compared with previous models. To compensate for the repositioning, Boeing added MCAS to replicate the handling characteristics of earlier models.

“I think it is unconscionable that a manufacturer, the FAA, and the airlines would have pilots flying an airplane without adequately training, or even providing available resources and sufficient documentation to understand the highly complex systems that differentiate this aircraft from prior models,” one pilot wrote in November. “The fact that this airplane requires such jury rigging to fly is a red flag. Now we know the systems employed are error prone — even if the pilots aren’t sure what those systems are, what redundancies are in place, and failure modes.”
 

p m

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Here's a quote from this article:
Slate said:
In order to accommodate the engine’s larger diameter, Boeing engineers had to move the point where the plane attaches to the wing. This, in turn, affected the way the plane handled. Most alarmingly, it left the plane with a tendency to pitch up, which could result in a dangerous aerodynamic stall.
It does not sound clearcut to me.
Okay, you have a larger engine, with a larger cowl; to gain more clearance under the engine, you decide to move the wings up on the fuselage. That puts the engine centerline closer to the body centerline, and should add little to no torque forcing the nose to go up.
It is only one part of it, I guess; another consequence is that the wings' center of drag is now higher with respect to the body centerline, which may have effect. It could also affect the efficiency of the empennage to control the flight, but it is even smaller effect.
I could only WAG that Boeing would not attempt anything dramatically affecting the aircraft's handling, and that the auto-pitch-down feature's action should not be overly dramatic. They also provided an override procedure for this, which the fallen aircraft crews may not have been trained on.

BTW, there are several aircraft designs that rely on the airframe ability to recover from stall - Piaggio Avanti and Long-EZ come to mind. They have a small canard in front and a large nearly triangular wing in the back; the nose will stall first, drop down, and the aircraft will gain airspeed (while losing altitude).
 

brian4d

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Dec 3, 2007
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High Point, NC
And to make things even stranger an older 767 (Amazon Air) crashed in texas a few weeks back the same way. Nose down into the ground.
 

brian4d

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Dec 3, 2007
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High Point, NC
Did you read the article?

The new tech was necessary because the modified engine placement causes the plane to pitch up.
I did, any control surface input should disengage the autopilot and therefore cancel out the sensor pitching the plane down. I find that article highly suspicious. Not saying it's not true but I find it hard to believe any aircraft manufacturer would roll out a new plane that's not aerodynamically sound. Not tail heavy, not nose heavy. If Orville and Wilbur would have done that they wouldn't have gotten 20 feet. Nose heavy planes fly bad, tail heavy plane fly once. You can take that to the bank.
 

Blue

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Mar 26, 2004
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Definitely Russia. And one of the mainstream lib media outlets managed to blame it on Donald Trump and his government shutdown. You can't make this shit up. I'll bet old W is finally glad everything isn't "Bush's fault."
 

jwest

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May 28, 2006
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WA & NC
Definitely Russia. And one of the mainstream lib media outlets managed to blame it on Donald Trump and his government shutdown. You can't make this shit up. I'll bet old W is finally glad everything isn't "Bush's fault."
Yeah, I saw that. However, the outlet did not do the blaming, they reported what someone else said. Not the same LOL
 

kennith

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Apr 22, 2004
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North Carolina
Yeah, I saw that. However, the outlet did not do the blaming, they reported what someone else said. Not the same LOL
It's far worse than the same. Any insulation they might once have had is expired, and I welcome any torment that befalls them.

Cheers,

Kennith
 

brian4d

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Dec 3, 2007
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High Point, NC
Good read here, say even more than what's already been covered.


Two take aways:

1.
Going against a long Boeing tradition of giving the pilot complete control of the aircraft, the MAX’s new MCAS automatic flight control system was designed to act in the background, without pilot input.

2.
Boeing decided that 737 pilots needed no extra training on the system — and indeed that they didn’t even need to know about it. It was not mentioned in their flight manuals.

If assessment is true Boeing will reel from this. Or worse.
 

pinkytoe69

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Jan 14, 2012
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minnesota
So this backs up the first article in that the fuckups here seem largely due to cost-cutting and profitability.

Neither Boeing nor the FAA look good right now.
 

brian4d

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Dec 3, 2007
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High Point, NC
So this backs up the first article in that the fuckups here seem largely due to cost-cutting and profitability.

Neither Boeing nor the FAA look good right now.
true story. I'm shocked Boeing went against their tradition of giving pilots full control. they broke the number one rule in the book. Pilots can't aviate if they don't have control. What a shame.
 

p m

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true story. I'm shocked Boeing went against their tradition of giving pilots full control. they broke the number one rule in the book. Pilots can't aviate if they don't have control. What a shame.
There's a difference between having control and having full control.
For instance, you don't have full control over fuel injection or ignition timing in your truck, but it doesn't mean you can't drive.
Likewise - in a stock coil-sprung Land Rover understeering is a built-in, inherent part of the vehicle. It doesn't mean you can't drive.
Traction control is an electronic built-in band-aid to allow incompetent drivers with bragging-rights horsepower and torque ratings to stay on the road, present in most vehicles on the market today.
Boeing's electronic intervention is an electronic band-aid to a diminished stability of the platform. It is also common as dirt everywhere in aircraft design. A B2 is fundamentally aerodynamically-unstable and can only be flown with super-fast and overwhelming computer control. So what?

The question (to me) is two-fold: (a) could Boeing's negative-feedback control to become positive-feedback under some conditions, natural or pilot-induced, and (b) how come it didn't happen in the U.S. but twice - in the market allowing people to become commercial pilots in as little as 240 hours including simulator?
 
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brian4d

Well-known member
Dec 3, 2007
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High Point, NC
There's a difference between having control and having full control.
For instance, you don't have full control over fuel injection or ignition timing in your truck, but it doesn't mean you can't drive.
Likewise - in a stock coil-sprung Land Rover understeering is a built-in, inherent part of the vehicle. It doesn't mean you can't drive.
Traction control is an electronic built-in band-aid to allow incompetent drivers with bragging-rights horsepower and torque ratings to stay on the road, present in most vehicles on the market today.
Boeing's electronic intervention is an electronic band-aid to a diminished stability of the platform. It is also common as dirt everywhere in aircraft design. A B2 is fundamentally aerodynamically-unstable and can only be flown with super-fast and overwhelming computer control. So what?

The question (to me) is two-fold: (a) could Boeing's negative-feedback control to become positive-feedback under some conditions, natural or pilot-induced, and (b) how come it didn't happen in the U.S. but twice - in the market allowing people to become commercial pilots in as little as 240 hours including simulator?
I'd argue they lost full control, that's why the biggest piece of the plane left is about 1 meter long. A rover traction control system or fuel injection system would not drive you off a cliff to your death. However, the Toyota Camry gas pedal issue may have done exactly that, hence all the lawsuits.

As for the Lancer, military planes designed to liveried bombs and take/utilize enhancements to fly. Passenger Military jets like the C-17 and C-5 you will not see that kind of tech. The HUGE exception would be the V-22. And that's a huge one. How many billions were spent there?