SUBSIM Radio Room Forums


SUBSIM: The Web's #1 BBS for all submarine and naval simulations since 1997

Go Back   SUBSIM Radio Room Forums > General > General Topics
Forget password? Reset here

Reply
 
Thread Tools Display Modes
Old 03-28-2019, 11:19 AM   #16
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Yes, the Orlando landing was a garden variety engine problem having nothing to do with the MCAS safety problem.

Just ran across a video by a pilot who ran the simulator to show exactly what an MCAS/trim system overrun malfunction looks like in the cockpit and how the trim cutout switch is part of the procedure. Note that MCAS malfunctions are part of a memory procedure: a procedure that pilots are required to memorize so they don't absolutely need to use the book to defang the problem.



Now you know exactly what the malfunction looks like in the cockpit, what steps are used to evaluate the problem and that competent pilots can handle it with the plane as it is now. You also know that American pilots, at least, can rehearse this event realistically in the simulator.
Rockin Robbins is offline   Reply With Quote
Old 03-28-2019, 07:37 PM   #17
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Blancolirio checks in with an update. There are disadvantages to having the angle of attack indicator. It takes experience to learn to fly using one and new and lesser hours pilots like the ones in Thailand, Indonesia and other Asian Pacific countries, Africa and South America would be less safe using one than not using one.

It will be interesting to see what Boeing comes up with. The bottom line is that if you're willing to kill yourself and your passengers with a perfectly good aircraft, no safety system that will ever exist can save you. Perhaps the thing to do for those outlying countries would be to require a pilot in the jump seat.

Rockin Robbins is offline   Reply With Quote
Old 03-28-2019, 07:49 PM   #18
Buddahaid
Shark above Space Chicken
 
Buddahaid's Avatar
 
Join Date: Jun 2008
Posts: 4,574
Downloads: 151
Uploads: 0


Default

Quote:
Originally Posted by Rockin Robbins View Post
It will be interesting to see what Boeing comes up with.
Boeing has already decided to offer the optional warning system that tells of disagreeing sensors as a retrofit at no charge as of a few days ago.
https://www.bbc.com/news/business-47722258
__________________

"However vast the darkness, we must provide our own light."
Stanley Kubrick
Buddahaid is offline   Reply With Quote
Old 03-29-2019, 07:34 AM   #19
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

They also need to attach both starboard and port angle of attack sensors to the MCAS system. On something so critical, redundancy on a persnickety (technical term, don't worry too much about it) sensor which has had problems should be required. Why is nobody talking about that obvious fix?
Rockin Robbins is offline   Reply With Quote
Old 03-29-2019, 07:42 AM   #20
Skybird
Soaring
 
Skybird's Avatar
 
Join Date: Sep 2001
Location: the mental asylum named Germany
Posts: 29,030
Downloads: 8
Uploads: 0


Default

It seems indeed that the MCAS trim theory has claimed dominance over the blowback theory. I only hope that this is due to the facts and not due to the circumstance that the MCAS trim problem could be "easily" adressed by a software update, whereas the blowback theory would indicate a problem of potentially project-killing proportions.
__________________
When a book entitled "A Hundred Authors Against Einstein" tried to refute the theory of relativity, Einstein replied: "Why a hundred? If I'm wrong, a single one already would suffice. "
Skybird is offline   Reply With Quote
Old 03-30-2019, 09:45 AM   #21
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Blowback theory would require the aircraft speed to vastly exceed never exceed speed, VNE. There's no evidence that either aircraft approached this speed and both black boxes would clearly indicate if that happened.

The press is, as usual, making a mess of their normally disgusting sensationalizing of a situation which is not unique in any way. Airbus has had very similar situations, and since it's European, the American press didn't land on them with crackpot theories and sensational accusations as they are doing to Boeing. Quit paying attention to these outlets who have abdicated their societal responsibilities in favor of whipping up fear to motivate sales of their deservedly failing publications.

Instead, pay attention to the community of airline pilots and the FAA itself. The outline of what will be done is clear now. The press' squealing about two so-called "essential" systems being sold as extras is a gross red herring. Check out the much more prosaic truth from a top airline pilot in a community of other highly qualified airline folks. And reflect: this man's life is dependent on the truth of what he says. He's likely telling you the exact unvarnished truth, no?

This whole public relations disaster, created by an ignorant and uncaring press, is much ado about routine matters. There is no airframe so safe that people cannot crash it. Ignorance is always more ingenious than intelligence.


Last edited by Rockin Robbins; 03-30-2019 at 11:21 AM.
Rockin Robbins is offline   Reply With Quote
Old 04-04-2019, 06:25 AM   #22
Skybird
Soaring
 
Skybird's Avatar
 
Join Date: Sep 2001
Location: the mental asylum named Germany
Posts: 29,030
Downloads: 8
Uploads: 0


Default

https://www.bbc.com/news/business-47812225
Quote:
A preliminary report into the crash of an Ethiopian Airlines plane last month says the aircraft nosedived several times before it crashed.

Pilots "repeatedly" followed procedures recommended by Boeing before the crash, according to the first official report into the disaster.

In a statement, the chief executive of Ethiopian Airlines, Tewolde GebreMariam, said he was "very proud" of the pilots' "high level of professional performance".
__________________
When a book entitled "A Hundred Authors Against Einstein" tried to refute the theory of relativity, Einstein replied: "Why a hundred? If I'm wrong, a single one already would suffice. "
Skybird is offline   Reply With Quote
Old 04-05-2019, 01:28 PM   #23
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Well, everybody woke up this morning to stories in BBC, Wall Street Journal and all over saying that the Ethiopian pilots "repeatedly did what the manual told them to do" and were crashed by the evil plane. And, as usual, the news media, having abdicated their responsibility to apply understanding to sometimes technical reports and find the truth, are merely selling paper and electrons by inappropriate use of laziness, fishing for controversy and finding it whether it exists or not, or just plain deception. Nowhere in these stories is the Ethiopian Preliminary Accident Report quoted or summarized point by point.

To get that critical information, and why the plane really crashed, you have to watch this video by blancolirio.

Mentor Pilot will undoubtedly follow with further clarification. The long and short of it is that the Ethiopian pilot made several fatal mistakes, after his low-time (less than 100 hours in type) co-pilot did the right thing and saved the airplane by engaging the trim cutout switches to shut down the MCAS system.

The plane dived for the first time, the pilot compensated with back pressure on the yoke while the copilot recommended that the trim cutout switches should be disengaged to keep the MCAS system from applying any more down trim. The pilot agreed and they disengaged the MCAS system and automatic trim controls. From that point on, MCAS had no influence on how the plane flew.

Because the plane had throttle settings for climb and was now flying level, airspeed very quickly increased beyond the Vmo (maximum operating speed) of the aircraft. This is when flight loads on the control surfaces make it very difficult or impossible to control the plane, even difficult or impossible to manually use the trim wheels with cranks on them that I showed you in a previous post. Cutting throttles was plainly indicated to reduce loads on the control surfaces and allow the pilot to regain trim and elevator control. Yet the throttles were never touched until impact and airspeed continued to increase (duh!) to over 500 knots. That's fatal mistake #1.

(I made my own fatal mistake #1 a couple of posts ago when discussing what Skybird called the "blowback" theory, where aerodynamic loads make control surfaces impossible to input. I said at that time that Vne (Velocity never exceed) speed was that threshold. Vne is the speed where things like wings, enpennage, cabin skin and other things are torn off the aircraft, you have actually structural failure due to aerodynamic loads. It's Vmo (Velocity maximum operating) where loads on control surfaces make the plane difficult or impossible to fly.)

Fatal mistake #2 was when the pilot and copilot together were unable to move the manual trim wheels (they were overstressed by the grossly inappropriate airspeed), they attempted to use the electrical trim switches on the yoke. With the trim cutout switches engaged, these switches were not operative. Their response was to make fatal mistake #3.

They turned MCAS back on by reengaging the trim cutout switches, MCAS trimmed the plane full down and killed them all. This action was against all training, all manuals, all simulator experience. It was the exact opposite of what should have been done.

The proper thing to do was to maintain level trim with yoke pressure, then reduce throttle to get the plane down to about 300 knots, at which point, considering the low altitude, back pressure and if necessary gently apply more throttle (to maintain proper climb speed) to establish a steady climb to a safe level. THEN and ONLY THEN, they should have stabilized attitude at level flight at cruise speed and manually trimming the aircraft would have been easily done.

But what does the so-called "news media" have to say today? The pilots followed every guideline and the MCAS system, which they turned off, repeatedly turned itself back on to crash the airplane. Completely, totally, indefensibly, irresponsibly, incompetently false. The pilot crashed the plane. End of story.

Can MCAS be improved? Heck yes. Both angle of attack sensors should be hooked to MCAS. MCAS should compare those sensors to each other and to the attitude indicator the autopilot uses to trim the airplane. It should turn off malfunctioning sensors as necessary and give the pilot an alarm to reflect what was done.

The MCAS system needs to be throttled back so that at all times pilot input overrules the MCAS system. At no time should the pilot simply lack the strength to overcome the down trim initiated by MCAS. (Well, at any speed below Vmo, anyway) It probably wouldn't be a bad idea that if the pilot exerts more than X pressure on the yoke, MCAS would be cut out automatically.

But no changes can prevent a pilot from killing everybody by turning a known malfunctioning MCAS system back on with a plane already completely out of his control, flying outside the design flight envelope of the plane. It's as if a terrorist hijacker took control, tried to crash the plane, the pilot and copilot overpowered him and promptly voluntarily let the terrorist fly crash again.

Okay so the immediate cause of the crash would be the terrorist. But the actual cause would be that the pilot put the terrorist back at the controls. That is the cause of the Ethiopian Airlines crash. Pilot error.

Last edited by Rockin Robbins; 04-05-2019 at 01:51 PM.
Rockin Robbins is offline   Reply With Quote
Old 04-06-2019, 06:03 AM   #24
Skybird
Soaring
 
Skybird's Avatar
 
Join Date: Sep 2001
Location: the mental asylum named Germany
Posts: 29,030
Downloads: 8
Uploads: 0


Default

Rocking Robbins, there were reports form very early on that Boeing did not provide trainign for the new system, at least not sufficiently, and that the written m,anuals distrubuted with many planes still do not contain cimplete documentation of the changes in cockpit and the MCAS' operation, and it still seems to that Boeing did so to avoid time-consuming certification processes by the FAA, which would have been a legal consequence form that, becasue new training means: "technology too new as if old certificaiton still covers it". While some very quick to try minimise the dmaage to Boeing by claiming its all a pilot error, pilots can only practice what they have been taught and have aquired in knoweldge. The latest report now, which is the preliminary official report, says that what could have been done, was done, but the MCAS system indeed showed to be unable to be switche doff - it seems to still have affected the plane while it already was formally switched of. And this speaks very severly for a very fundamental software error.


Meanwhile, the FAA have accused Boeing of another serious software problem with the 737 Max, it is unrelated to the crashes and the MCAS problem and they did not say over here in our media what exactly it is - but it is severe enough that the FAA ruled that even with this problem alone the planes would stay grounded due to unacceptable risks. Boeing of course again says that it is minor and not means much. Well, they also said the plane and MCAS was okay and functionally right immediately after the crashes. They do not state the MCAS to be fully intact anymore by now, do they.


Boeing gets it hard currently. The yhave been found guilty of illegal state subventions (like Airbus before), and today I read that they had to announce a cut by over 20% in their planned monthly production rate of the 737. A planned update of the MCAS software that by now already should have been released, had to be delayed again because they found the update to be faulty as well.


The whole design of the plane is dubious a bit, I must say. When the new generation of A320s took the lead in the order statistics, Boeing kind of panicked and tried to squeeze another latest update out of an airframe and plane series that by now already is squeezed quite hard. Lets face it, the 737 is an old man in the business. To be more economical in fuel consummation, the engines became bigger. For this the whole airframe geometry and balance changed, and for compensating this, a workaround had to be found, which was the MCAS trim software. The MCAS as present today is a workaround in itslf already, to balance the messed up airframe geometry which was originally not planned for having such big, heavy engines this far to the front of the airframe. All this are drastic, fundamental changes, and were done in not even half the time that Boeing usually plans for work projects of this volume and size. Boeing did ignore its own internal safety regulationsn and testing procedures, to save time on the galloping orders coming in for the Airbus 320.



This paragraph above I quote by the witnessing of a former Boeing engineer who was throughly quoted in a long essay in a German newspaper a week ago or so. He reports by his own experience, he was engaged in the 737 Max development. He said the pressure set up by the management was immense and such as he had never experienced it ever before. Already during the work, he indicated, he felt concerned for the safety of the project. The time pressure was so immense that they did not even fit into the cockpit the new generation of certain cockpit gauges that are available already and would have been commanded to be used by the chnages in the Max model. Doing so would have costed time and so even some old-fashioned analogue displays were used once again, while better alterntaives are avalable since long. - Says this engineer.



It looks as if the 737Max was designed not with security as a priprity, but getting a quick reaction to the A320 AT ALL COST. Time was the priority, nothing else.



They overplayed their cards. Thats what it looks like to me. Over 300 people paid with their lives for this gamble. I do not buy this pilot error's theory. Thats just pawns they want to sacrifice to distract from the company's failure at boss level. Boeing pushed to hrd, too fast, too far, and broke it. Again that egineer: they cut short and ignored their own internal Boeing security and safety routines and testing procedures, that was his conclusion. And I will continue to think so as long as no new, massive changes to the information status become known.
__________________
When a book entitled "A Hundred Authors Against Einstein" tried to refute the theory of relativity, Einstein replied: "Why a hundred? If I'm wrong, a single one already would suffice. "
Skybird is offline   Reply With Quote
Old 04-06-2019, 01:59 PM   #25
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Quote:
Originally Posted by Skybird View Post
The latest report now, which is the preliminary official report, says that what could have been done, was done,
No, it shows that the pilot acted against memory procedures in the case of a trim overrun/MCAS malfunction. After the co-pilot switched the motorized trim system off, the pilot, against all procedures in the 737 from the first flight 40 years ago, turned the electric trim system back on. It did not throw its own switch back to the on position. The captain threw the trim system cutout switch back to the on position. Having overpowered the terrorist threatening to crash the plane, the captain voluntarily put the terrorist back at the controls of the aircraft, according to the Preliminary Accident Report. We now resume our previously running falsehoods

Quote:
Originally Posted by Skybird View Post
...but the MCAS system indeed showed to be unable to be switche doff - it seems to still have affected the plane while it already was formally switched of. And this speaks very severly for a very fundamental software error.
Again, with the high airspeed the pilot and copilot together couldn't turn the manual trim wheels on either side of the console. The captain then killed everyone by switching the trim system override switch back on so it could crash the plane. It did not turn itself back on. That is not possible. It did not affect the plane, as shown by black box records which show what MCAS wanted to do to the trim but couldn't because the co-pilot saved the plane by turning trim motors off with the trim system cutout switch, as per 40 year old procedures in the entire 737 series of aircraft. The black box clearly says the MCAS commanded x units of down trim but was prevented from doing so by the trim system cutout switch. The actual data is that clear. As long as the trim system cutout switch was off, MCAS commands were never executed by the trim motors. Indeed, they COULD not have been.


Quote:
Originally Posted by Skybird View Post
Meanwhile, the FAA have accused Boeing of another serious software problem with the 737 Max, it is unrelated to the crashes and the MCAS problem and they did not say over here in our media what exactly it is - but it is severe enough that the FAA ruled that even with this problem alone the planes would stay grounded due to unacceptable risks. Boeing of course again says that it is minor and not means much. Well, they also said the plane and MCAS was okay and functionally right immediately after the crashes. They do not state the MCAS to be fully intact anymore by now, do they.
I'll believe it when I see it. As it is, this whole paragraph is unsubstantiated gossip, worthy of disdain. Facts are stubborn things and only they matter. What people with agendas have to say about the situation is worth nothing.

Quote:
Originally Posted by Skybird View Post
A planned update of the MCAS software that by now already should have been released, had to be delayed again because they found the update to be faulty as well.
The plane won't be fixed by software changes. Mechanically, more sensors need to be hooked up to the MCAS system. MCAS must be able to be overpowered by pilot input in all circumstances slower than Vmo. The computer must let pilots know when there is disagreement between the three sensors measuring attitude and wing angle of attack. Those are physical, not software changes. They still won't keep people from being stupid, ignoring every flying concept they've ever learned, as the Ethiopian pilot did, and killing everybody. Perhaps in third world countries a qualified pilot should be required to ride along in the jump seat too.


Quote:
Originally Posted by Skybird View Post
It looks as if the 737Max was designed not with security as a priprity, but getting a quick reaction to the A320 AT ALL COST. Time was the priority, nothing else.
That's a ridiculous fabrication. The reason you go with a tried and true design for the basis of the 737 Max program is that the 737 is an airframe with a long-standing record of reliability and safety. You don't invent new mistakes when you have a thoroughly debugged platform to build from.

They took a proven airframe, widened the body, put more modern engines on it, compensated for the changes (the exact same compensations pilots make every day when cargo or people are distributed differently than the flight plan calls for and they have to compensate for a center of gravity different than anticipated.

The procedure for an MCAS failure is identical to the procedure for a trim overrun on any 737 produced since Fred and Barney Flintstone rode dinosaurs: switch off the trim system override switch. Regain control of the aircraft at a safe altitude in level flight. Then manually use the manual trim adjustment wheels on both sides of the console to set the trim you need. Then resume the flight without incident. This is a memory procedure, known to all 737 series pilots, required to be recited from memory as part of their qualification for a type certificate allowing them to fly 737 series aircraft.

Every 737 pilot for the past three generations has had the information memorized to save the airplane in the situation that killed both of these 737 Max aircraft. Switch the trim system override switch off. That was true for the very first 737 flight in April 1967. It is still true today. Had the Ethiopian pilot followed the procedure that he's absolutely required to know in order to get behind the controls, that aircraft would not have crashed. End of story.


Quote:
Originally Posted by Skybird View Post
They overplayed their cards. Thats what it looks like to me. Over 300 people paid with their lives for this gamble. I do not buy this pilot error's theory. Thats just pawns they want to sacrifice to distract from the company's failure at boss level. Boeing pushed to hrd, too fast, too far, and broke it. Again that egineer: they cut short and ignored their own internal Boeing security and safety routines and testing procedures, that was his conclusion. And I will continue to think so as long as no new, massive changes to the information status become known.
Yup, big evil corporation sought to kill poor Ethiopian victims by greed and hubris. THAT's the story that's unbelievable here. The official Preliminary Accident Report makes it crystal clear that pilot, against the good sense of his low time co-pilot who saved the plane, promptly snatched defeat from the jaws of victory to crash the plane. He violated 40 year old memory procedures to do so and others paid and are paying the price.

Can the plane be made safer? All planes can be made safer. Just keep them on the ground. But no matter what, no safety system can prevent a pilot from taking leave of his senses, ignoring everything he's learned in his entire life about flying, and crashing a perfectly good airplane.

Proper procedure in this situation was followed up to the point where the co-pilot recommended, the pilot agreed and one of them switched off the trim system cutout switch. At that point the pilot was in command of his aircraft.

Proper procedure would be to gain control of the airframe. Throttle had to be reduced to level attitude cruise position, instead of leaving it in full climb 94% throttle position. Then using yoke only, the pilot should gain control of the aircraft in level flight. Having done that, he should gently increase throttle to best rate of climb setting while he raises the nose with the yoke. No attempts to debug the trim system should be done until the airplane is safe.

Once the plane is at a safe cruise altitude, the pilot should have reduced throttle to level cruise setting and assumed a level cruise attitude. Then the manual trims would easily have been used by either pilot or co-pilot to unload the control yoke. The flight could then either resume to its destination without incident or return to takeoff airfield as management, tower or pilot deemed advisable.

First, FLY THE PLANE. Then look to solve other problems. It's the first thing you learn in ground school before the first time you fly. This pilot tossed that life-saving proverb out the window, killing all aboard.

Last edited by Rockin Robbins; 04-06-2019 at 02:51 PM.
Rockin Robbins is offline   Reply With Quote
Old 04-06-2019, 02:39 PM   #26
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Oh, and Skybird pretends that MCAS is a kludge, produced out of thin air to save a 737 the couldn't fly right. Surprise! MCAS is also used in other airplanes without incidents. The military KC-46 tanker also uses MCAS and has never had a crash resulting from similar pilot errors. The KC-46's MCAS is different from that of the 737 Max in that it uses both angle of attack sensors and the Air Force required pilot input to the yoke to cancel any MCAS operation.

Had the 737 Max been that way and pilots disconneted MCAS and subsequently crashed the plane, we would be reading the same news reports that the greedy airline company allowed pilots to disconnect a system that could have saved 150 lives, and instead allowed the pilot to crash the plane.

The FAA, news-media, politicians and certain people posting on Subsim would still be reciting the same tired old yarns about the greedy airline sacrificing all to get the plane in flight sooner than it could be for safety. These greedy companies don't care about the safety of their customers. I guess dead customers buy a lot of airplanes and the manufacturers don't have to worry about customer safety.

As farcical as the argument is to begin with, ANY MCAS configuration would have the same group of anti-corporation zealots screaming for executives to go to jail and companies to be put out of business. The only solution is to remove all airlines from the air and not let any of them fly. But that wouldn't keep the zealots from keening. Actually, the agenda is to attack corporations with anything that occurs. And those attacks will continue regardless of what those corporations do. There is no right as far as these zealots are concerned, but the death of the corporations. Then the zealots would attempt to evade responsibility for everyone's inability to fly or send cargo by air to remote destinations.
Rockin Robbins is offline   Reply With Quote
Old 04-06-2019, 03:19 PM   #27
Skybird
Soaring
 
Skybird's Avatar
 
Join Date: Sep 2001
Location: the mental asylum named Germany
Posts: 29,030
Downloads: 8
Uploads: 0


Default

From here on you are alone with yourself.
__________________
When a book entitled "A Hundred Authors Against Einstein" tried to refute the theory of relativity, Einstein replied: "Why a hundred? If I'm wrong, a single one already would suffice. "
Skybird is offline   Reply With Quote
Old 04-06-2019, 03:27 PM   #28
Buddahaid
Shark above Space Chicken
 
Buddahaid's Avatar
 
Join Date: Jun 2008
Posts: 4,574
Downloads: 151
Uploads: 0


Default

Not really. I agree with RR.
__________________

"However vast the darkness, we must provide our own light."
Stanley Kubrick
Buddahaid is offline   Reply With Quote
Old 04-07-2019, 07:36 PM   #29
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

I have a lot of friends who are pilots. Some of them are commercial pilots. They agree with blancolirio, that the news media has invented their own story and run with it when critical lessons need to be learned.

Some of our commercial pilots, especially third world commercial pilots, are flying by the book, so far as they can remember it, and lack the actual stick and rudder skills that save airplanes when things go wrong. If a book of rules was all you need, then planes would fly automatically. They have pilots because we realize that no book of procedures can anticipate every eventuality.

A pilot with actual "fly by the seat of your pants" stick and rudder skills has an instrument scan that is second nature. He knows proper power settings for level cruise, best rate of climb, best angle of climb, descent and rapid descent. He knows the proper airspeeds, throttle settings, likely trim settings for each, not by looking them up in a book, he knows them as well as his name.

When he's in a plane with throttles set at 94% for climb, and it's traveling over maximum operating speed, he knows instinctively to reduce throttle. The Ethiopian pilot left his throttle at 94%, never touching the throttle through 10 minutes of level or descending flight. He took his plane, which at that altitude should never go above about 340 knots all the way up to 500 and made absolutely no throttle corrections for TEN MINUTES.

That's pilot error in all caps, italicized, underlined and bolded. In 64 point type even. No low time pilot of a Cessna 172 would do such a thing and not lose his flying license.

How pathetic is our so-called "news media" for representing the words of Ethiopian Airlines, powerfully motivated to exculpate itself (how in hades were these pilots even CERTIFIED? Boeing does not certify pilots of Ethiopian Airlines.) and its pilots, whose actions reflect on the Airline. The pilots "repeatedly followed procedures recommended by Boeing before the crash." Whose words are those? They certainly do not reflect the words of the Preliminary Accident Report! It clearly says that the co-pilot recommended, the pilot agreed and the elevator trim cutout switch was turned off per memory procedures for elevator trim overrun. It clearly says that while turned off MCAS commanded a number of units of down trim, which couldn't be executed because the trim cutout switch was off. It clearly says the cutout switch was turned back on, against trim overrun instructions in the 737 manual since 1967. It clearly says the pilot then used the trim switch on his yoke to trim up. It clearly says that MCAS, having been erroneously turned back on by the pilot, then gave full down trim at 500 knots, immediately crashing the aircraft. It clearly says that what happened was pure pilot error.

Again, it is as if a terrorist had seized control of the plane and dived it to crash everyone. But the crew overpowered him and recovered control of the airplane. Then they decided that the terrorist could handle the situation better than they could and voluntarily put him back at the controls. Now they want to blame the terrorist. Bullschnitzel. The pilot crashed the plane.

Don't forget that Airbus had a situation where the plane was so automatic that pilots could not reduce throttle. It would not respond to yoke movement, trim controls, the pilots were completely locked out of interfering with a crashing airplane and it killed lots more than 150 people. But Airbus is European. Boeing is American. I smell anti-Americanism in this mix as well.

Mistakes are equal opportunity oppressors. They respect no nationality, corporate identity, economic system or culture. They sneak in everywhere, regardless of measures taken to avoid them. This situation has nothing to do with the United States, Boeing, or even Ethiopian Airlines. Mistakes were made. They need to be identified and remedied. There is nothing to be gained by punishment or retribution here. All that does is make the ones who made the mistake clam up. Openness, unprejudiced and fact-based evaluation of the events is the only proper course to ensure that similar situations don't happen again.

Last edited by Rockin Robbins; 04-07-2019 at 08:02 PM.
Rockin Robbins is offline   Reply With Quote
Old 04-08-2019, 12:52 PM   #30
Rockin Robbins
Navy Seal
 
Join Date: Mar 2007
Location: DeLand, FL
Posts: 8,909
Downloads: 135
Uploads: 52


Default

Here are the complete instructions issued to Ethiopian Airlines regarding alterations to their Flight Crew Operations Manual (FCOM) and the complete contents of that insert. This is copied and OCR'd from the pdf of the Preliminary Crash Report, which I linked above. Remember, we're paying no attention to uninformed conclusions, we care about the EVIDENCE. Red highlighting is mine:

IssueDate: November 6, 2018
Airplane Effectivity: 737-8 /-9
Subject: Uncommanded Nose Down Stabilizer Trim Due to Erroneous Angle of
Attack (AOA) During Manual Flight Only
Reason: To Emphasize the Procedures Provided in the Runaway Stabilizer Non-
Normal Checklist (NNC).
Information in this bulletin is recommended by The Boeing Company, but may not be FAA approred
Ae ae i RE a the ex ent of conflict ith the FAA approved Airplane Flight Mammal
Berein 2% BIg 2 direct or indirect bearing on E ae Do af i adel solane.
THE FOLLOWING PROCEDURE AND/OR INFORMATION 1S EFFECTIVE UPON RECEIPT
Background Information
The Indonesian National Transportation Safety Committee has indicated that
Lion Air flight 610 experienced erroneous AOA data
. Boeing would like to call
attention to an AOA failure condition that can occur during manual flight only.
This bulletin directs flight crews to existing procedures to address this condition.
In the event of erroneous AOA data, the pitch trim system can trim the stabilizer
nose down in increments lasting up to 10 seconds. The nose down stabilizer trim
movement can be stopped and reversed with the use of the electric stabilizer trim
switches but may restart 5 seconds after the electric stabilizer trim switches are
released. Repetitive cycles of uncommanded nose down stabilizer continue to
occur unless the stabilizer trim system is deactivated through use of both STAB
TRIM CUTOUT switches in accordance with the existing procedures in the
Runaway Stabilizer NNC. It is possible for the stabilizer to reach the nose down
limit unless the system inputs are counteracted completely by pilot trim inputsFlight Crew Operations Manual Bulletin No. ETH-13 , Dated November 6, 2018 (continued)
Additionally, pilots are reminded that an erroneous AOA can cause some or all of
the following indications and effects:
» Continuous or intermittent stick shaker on the affected side only.
* Minimum speed bar (red and black) on the affected side only.
» Increasing nose down control forces.
» Inability to engage autopilot.
° Automatic disengagement of autopilot.
» IAS DISAGREE alert.
°. ALT DISAGREE alert.
» AOA DISAGREE alert (if the AOA indicator option is installed)
. FEEL DIFF PRESS light.
Operating Instructions
In the event an uncommanded nose down stabilizer trim is experienced on the
737-8 /-9, in conjunction with one or more of the above indications or effects, do
the Runaway Stabilizer NNC ensuring that the STAB TRIM CUTOUT switches
are set to CUTOUT and stay in the CUTOUT position for the remainder of the
flight.

Note: Initially, higher control forces may be needed to overcome any
stabilizer nose down trim already applied. Electric stabilizer trim can
be used to neutralize control column pitch forces before moving the
STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim
can be used after the STAB TRIM CUTOUT switches are moved to
CUTOUT.


Administrative Information
Insert this bulletin behind the Bulletin Record page in Volume 1 of your Flight
Crew Operations Manual (FCOM). Amend the FCOM Bulletin Record page to
show bulletin ETH-12 "In Effect" (IE).
This Bulletin remains in effect until Boeing provides additional information on
system updates that may allow this Bulletin to be canceled.
Please send all correspondence regarding Flight Crew Operations Manual
Bulletin status, to the 737 Manager, Flight Technical Data, through the Service
Requests Application (SR App) on the MyBoeingFleet hom

I call that full disclosure. I call the crash 100% pilot error. Boeing didn't wait for the FAA to issue guidelines. On it's own nickel Boeing issued this advisory and manditory FCOM insert completely describing the cause, effects and proper crew remediation for exactly what happened on the Ethiopian Airlines crash. Having all the information in their hands which would have saved the flight, through pilot error this plane crashed.

Last edited by Rockin Robbins; 04-08-2019 at 01:05 PM.
Rockin Robbins is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:33 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright © 1995- 2019 Subsim