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Old 04-19-19, 09:10 AM   #1
Dowly
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Originally Posted by Rockin Robbins View Post
With nose trimmed down the plane accelerates from gravity. The proper thing to do is reduce throttle to keep speeds from destroying the airframe.
You do realise that AND trim doesn't mean the plane is pointing down? Check the preliminary report, the aircraft was flying slightly nose up or at level for most of the flight until MCAS pointed it down.

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Absolutely false.
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The Maneuvering Characteristics Augmentation System (MCAS) flight control law was designed and certified for the 737 MAX to enhance the pitch stability of the airplane – so that it feels and flies like other 737s.
From: https://www.boeing.com/commercial/73...e-updates.page
Due to the way the engines are placed and being bigger makes the MAX nose up at speed, which is why the MCAS system was put in place to counter that. In other words, it's a band aid.


As for Mentour Pilot's video; since his Q&A videos seem to have been removed from his channel I can't verify, but from what I remember he removed the video because it was indeed speculation, but I don't recall him calling it factually wrong. It does show what pilots, who know what is going on, can do to try recover from the situation. In that they failed, because the manual trim was so hard to use even at <340kts speed.


He also mentioned in the now removed Q&A video that he made the video to show what the situation must have been in the cockpit because he didn't like how people (like you) put the blame on the pilots.
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Old 04-19-19, 01:17 PM   #2
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Originally Posted by Dowly View Post
Check the preliminary report, the aircraft was flying slightly nose up or at level for most of the flight until MCAS pointed it down.
The nose was level or slightly up during takeoff (no MCAS) and after they threw the electric trim cutout switches to "cutout," when MCAS was not operative, It tried to send down trim signals to the trim motor, but the trim cutout switch prevented it from trimming the plane down. As a matter of fact, for more than half the flight there were no trim changes at all! You can see that for half the flight, MCAS was off, all trims were input by the pilot. Then for unknown reasons, the pilot decided that a known malfunctioning MCAS could fly the plane better than he could. He turned the cutout switches back to on and allowed MCAS to crash the plane. That's pilot error

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Originally Posted by Dowly View Post
From: https://www.boeing.com/commercial/73...e-updates.page
Due to the way the engines are placed and being bigger makes the MAX nose up at speed, which is why the MCAS system was put in place to counter that. In other words, it's a band aid.
As both Mentour Pilot and blancolirio have said, pilots who flew the 737 MAX with MCAS turned off were barely conscious that there was any difference to the feel of the aircraft. Flying the plane without MCAS was not only possible, it was easy and straightforward, done without difficulty by 737 pilots. That's the real tragedy here, that a system to introduce very subtle "feel" differences in how a plane flies could have the power to crash a plane when the pilot makes an error. Whether pilot error is the ultimate cause or not, the PROXIMATE cause was MCAS diving the plane 8.000 feet into the ground.

If MCAS automatically turned off for the remainder of the flight when the pilot input 2 units or more of electric trim in the opposite direction as MCAS trim, the plane wouldn't have crashed.

If the amount of down trim MCAS could dial into the stab was limited to under four units, the control console could easily overpower MCAS and the plane wouldn't have crashed.

But let's be fair here. If the plane were really in a stalled condition and the pilot could overpower MCAS to pitch the plane even further up, the headline would be "Boeing Automatic Systems Unable to Save 150 Deaths." And the nay-sayers would be crowing that the automatic system could have saved the plane, but wasn't powerful enough to do so. In the safety biz, you are always wrong.


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Originally Posted by Dowly View Post
As for Mentour Pilot's video; since his Q&A videos seem to have been removed from his channel I can't verify, but from what I remember he removed the video because it was indeed speculation, but I don't recall him calling it factually wrong. It does show what pilots, who know what is going on, can do to try recover from the situation. In that they failed, because the manual trim was so hard to use even at <340kts speed. He also mentioned in the now removed Q&A video that he made the video to show what the situation must have been in the cockpit because he didn't like how people (like you) put the blame on the pilots.
Note that 340 knots is 90 knots higher than the "speed limit" below 10,000 feet of 250 knots.

He said "I was wrong. I was speculating, not giving the hard facts that you expect from me." I'm not blaming the pilots. I'm saying that pilot error was the cause of the crash. They would be the first to expect us to find the truth and let everyone know how to avoid making their mistake. It is clear, according to the only source of facts we have, the Preliminary Accident Report, that the pilots, through wrong decisions in conflict with the Aircraft Flight Manual regarding elevator trim overrun situations, caused this plane to crash. They were helped by the ability of a system meant to introduce subtle "feel" that imitated the "feel" of other 737 series planes, having the power to input full down elevator that the pilots would be unable to overpower.

The problem is that the general public treats this stuff like a football game. Pick a side and cheer for them, it's "us" against "them." And "them" need to be punished or executed. Real air accident investigation works entirely differently. Realizing that punishing erroneous decisions results in people clamming up and not saying the words that save future lives, air transportation safety agencies are not an adversarial procedure, but a search for the truth and a search for actions that will prevent future similar accidents.

As long as humans live on the face of this planet, human error will occur, sometimes costing the lives of hundreds or thousands of people. Often those making the error pay with their lives and can't be punished later anyway. But when they don't, unless they committed crimes, punishment only forces them not to talk about what went wrong. Air traffic investigation is solely (in theory and mostly in practice) about preventing recurrence of tragedy.

Last edited by Rockin Robbins; 04-19-19 at 01:27 PM.
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Old 04-21-19, 09:17 AM   #3
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Boeing employees raise further accusations over shoddy production standards at Boeing, this time the Dreamliner.

https://www.nytimes.com/2019/04/20/b...th=login-email
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Old 04-22-19, 06:42 AM   #4
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Originally Posted by Skybird View Post
Boeing employees raise further accusations over shoddy production standards at Boeing, this time the Dreamliner.

https://www.nytimes.com/2019/04/20/b...th=login-email
Flew to and from Mexico last October in a Dreamliner (only a month old as far as I was aware) and I recall on the homeward flight the steward passing out paper towels to a couple a few seats ahead off us because the ceiling was dripping water (and this was in first calass).
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Old 04-22-19, 11:09 PM   #5
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You couldn't pay me the Earth's weight in gold to fly in anything French.

I also happily drive where I need to go. If I can't drive there, I have no business there. But some people don't have that luxury. In short, I don't trust anything with wings, no matter who built it.

What would really help these companies is going 100% automated. It would atleast shut the Union idiots up.
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Old 04-23-19, 05:21 AM   #6
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^ Well, the french literally invented flying. I mean the Wright brothers were first (or maybe Karl Jatho even earlier), but their design had no real chance in the long run.
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Old 04-29-19, 08:49 AM   #7
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Boeing slides deeper into it.

https://www.dayandnightnews.org/faa-...t-year-source/

https://www.japantimes.co.jp/news/20...m-woes-source/

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The inspectors learned that Boeing had opted to make the malfunction signal optional and an extra that would cost more money.
This came after Southwest asked Boeing to reactivate the signal after the Lion Air crash, which killed all 189 people on board.
Boeing had deactivated the signal on all 737 Max delivered to Southwest without telling the carrier.
Neither the airline nor its pilots were aware of these changes when they started flying the planes in 2017, a spokeswoman for Southwest told AFP.
What the hell was Boeing thinking.

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Called “disagree lights” in Boeing parlance, these lights turn on when faulty information is sent from so-called angle of attack sensors to the MCAS. Those sensors monitor whether the wings have enough lift to keep the plane flying.
In the case of the Lion Air crash, investigators think one of the angle of attack sensors may have failed and sent incorrect data to the MCAS, causing its nose to go down as pilots fought to bring it back up.
The MCAS overrides the pilots manual efforts to point the plane up or down.
With the angle of attack sensor not working properly, the thing to do would have been to turn off the MCAS. But the Lion Air cockpit crew did not know this.
What the hell was Boeing thinking. Heads must roll for this. Decision-makers must go behind bars. A a super-hefty financial penalty is on order. Additional to the damage compensations for the victims' families. And additionally to the compensations for the carriers whose fleets of 737 max are grounded.


What the hell were they thinking...???

A good news in all the bad news for the families of the pilots. The cheap get-out-of-dodge-theory of "pilot error" is almost ridiculous by now.
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