Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

[Heliian]

Regardless of training or experience, this mcas system should not have been designed with such a malicious single point of failure.

One sensor failed and drove the trim into a physically unrecoverable position. Input on the controls isn't enough and the manual trim may not even be moveable due to aerodynamic loads. Combine this with no altitude and it's a deadly combination.

What you say is true and not true.

It is true that Boeing should have learned from Turkish incident not to use a single input. that is in my mind completely stupid.


The statement you use to say that it drives the trim to an unrecoverable position is not true - unless you do nothing about it. As proven in the Lion air accident and in the bulletins from Boeing - the system is can be fully over-ridden. If the pilot input a nose up trim command from his yoke switch - the system stops the nose down input and then trims nose up. the procedure is to trim nose up to as stable a position as possible and then to flip the disconnect switches.....voila! No 50 turns of the trim wheel. When the Lion air crew transferred control from the captain to the FO - the FO did not fight the system as much and essentially let the airplane fly him.

Aha! I don't think that anyone would catch the trim until at least the second activation. If you then shut off the electric trim to avoid a third or fourth activation, you now have to manually roll back the wheel. By that time, you cannot crank it fast enough. The pilot flying would be double handing to keep it up and cojo is using left hand on the wheel. It's a crap situation to be in.

[yycflyguy]

Do you guys think the max will stay on the NG type rating when the dust settles, or will it require its own simulator and type designation?

Too much money riding on this. Too much ego riding on this. It'll be software patch with "enhanced" training and that's about it. I think it'll be in the air before the summer rush.

We’ll be good to go but how willing, or should I say trusting, will the fare paying passengers be. Will they be good to go?

90% of the passengers have no clue what airplane they are on, or what the difference is between a 767 and 737; let alone the difference between a 737NG and MAX. If it saves them $20 on their internet search they will book and complain later.

[complexintentions]

90% of the passengers have no clue what airplane they are on, or what the difference is between a 767 and 737; let alone the difference between a 737NG and MAX. If it saves them $20 on their internet search they will book and complain later.

Yep. And by then they'll be on to the next scary thing they read about on Facebook.

Fortunately for Boeing internet stupidity works both ways.

[Gino Under]

The reality in all of this is simply that the FSB for the MAX makes no mention of the MCAS system. Even the abbreviation MCAS is missing in the report. So, it seems unlikely to me that the MCAS would be part of the recommended differences training for pilots flying the NG converting to the MAX or that they would even be aware of the MCAS system, which clearly seems to be the case. To be truthful, I simply wouldn’t know if it was included in that CBT or not. I have my doubt.
MCAS is covered in the maintenance SDS but not the pilot FCOM. The SDS doesn't say much except, no big deal, pilots can use the STAB TRIM RUNAWAY NNC. (a memory item). It's the difference in behaviour that may have confused the pilots and delayed their response. Something they must not have realized in the moment. Too late. Two hits on the stab trim in opposition to the uncommanded trim and you’re full nose down.

Many here are trying to defend an MCAS runaway as something easy, peasy, no big deal. If it were of little concern to MAX pilots, you’d think it would also seem odd to those with such a positive attitude that American Airlines and Southwest Airlines Pilot unions are questioning Boeing’s CBT approach to the differences training that omitted MCAS. These two airlines have lots of experience with the B737 and Boeing.
Boeing is said to have offered a warning light installation as an option for a single source failure point. Now Boeing will have to explain to regulators why they decided safety should be an option. It usually isn’t.

I suggest reservations may be because one, it wasn’t mentioned in the FSB report, and two, it therefore wasn’t in the CBT. This is why I think those who undertook CBT differences training can readily identify they’ve had incomplete or inadequate differences training. In these two MAX losses they now see the difference between a STAB TRIM RUNAWAY and an MCAS event and how it could lead to confusion during a critical phase of flight.

Gino

[Eric Janson]

@Eric Janson,

I appreciate your viewpoint and do not mean to diminish the difficulties facing both accident crews. Certainly it is possible the multiple events, particularly something as alarming as the stick shaker could mask the sound of the trim running. Still, if there is any aircraft where it is quite uniquely hard to not notice the trim operating, it's got to be a 737 with those dual trim wheels? I cannot think of a mainstream airliner operating that gives more visible, audible, and tactile feedback of trim operation. And if not, surely the pitch down and increasingly heavy yoke would provide further clues? I mean if the elevators are responding to pitch inputs surely that would lead one to the only remaining pitch surface, the horizontal stabilizer? Never mind if it's some fancy system Boeing grafted onto a Franken37 or just a "regular" trim runaway malfunction.

If I feel ANY flight control operating against my input it is my desperate, immediate first priority to get control back, not hunt for just the right page in the QRH. I can see how the MCAS design would be confusing, operating then stopping repeatedly, especially since Boeing didn't deem pilots worthy of knowing how the damn thing works (or that it existed). But how many cycles of that nonsense would you wait before you cut the thing out of the picture? Are experienced airline pilots really that unaware of the magnitude of control authority of the horizontal stab? Sincere question, not facetious.

Yes, they had several things working against them. But they (2nd crash) also had daylight, altitude, time, and according to Ethiopian, prior knowledge of the 1st accident and AD, working for them.

It really was not my intent to malign the crew or imply that the failure was "simple", but as is probably obvious I do tend to think (pending further information) that it should have been survivable. The fact is was not is very sad for more than one reason.

You make valid points - the 'why?' question will hopefully be answered in the accident reports.

I'm sure the accident report(s) will show Training/CRM/Maintenance/Cultural issues.

Especially at Lion Air where they have almost zero safety culture. Their AOC should have been pulled imho.

The fact that 3 separate crews apparently couldn't handle a combination of failures is a huge Red Flag.

It appears that only a Pilot sitting on the jumpseat prevented the fatal outcome of the other 2 events. Even in that event the flight was continued to destination - I guess we're at the point now where Airmanship and Common Sense have completely disappeared.

A system that trims then stops then starts again isn't a runaway trim in my book - the fact that Pilots were unaware of MCAS is Criminal Negligence as far as I'm concerned.

The present day Boeing company with its Virtue Signalling CEO, 'Diversity' and 'Equality" (of outcome) doesn't resemble the Boeing I experienced first hand in the late 90s in any way.

https://www.nytimes.com/2019/03/23/busi ... crash.html

[Laser Tilt]

https://www.businessinsider.com/lion-ai ... ort-2019-3

I guess the question is whether the pilots were trained to deal with the situation. I suspect not.

--------------------------------------------------------------------

Pilots in the Lion Air 737 Max crash tried to prevent it by hitting an override switch again and again, unaware there were 3 other steps they needed to take, report claims
Bill Bostock 7m
lion air plane crash debris.JPG
Personnel from Indonesia's National Transportation Safety Board examine debris from the downed Lion Air flight at Tanjung Priok port in Jakarta on November 1, 2018. Beawiharta/Reuters
Pilots on a fatal Lion Air 737 Max flight reportedly hit an override switch dozens of times in a bid to stop them crashing, sources told The New York Times.
According to the sources, the switch turned off software called MCAS, which was wrongly forcing the plane into a dive.
Pressing the switch was the right first step, they said, but needed to be followed by pressing two more switches to turn off a motor which was pointing the plane downward.
The final step, the sources said, was to turn a wheel that would have righted the plane.
The official investigation has yet to return a conclusion. The flight crashed in October in Indonesia, killing all 189 people on board.
The pilots of the Lion Air 737 Max 8 which crashed last year reportedly hit an override switch repeatedly in an effort to save the plane, unaware that they needed to take three further steps

According to sources investigating the crash, who spoke to The New York Times, the pilots flying the Boeing plane pressed a switch meant to suppress a piece of software called the Maneuvering Characteristics Augmentation System (MCAS), which was forcing the plane into a dive.

The plane crashed less than 15 minutes after take-off from Jakarta's Soekarno-Hatta International Airport, killing all 189 people on board.


The sources said that, while the MCAS override switch was the right first move, there were three more steps which needed to be taken to save the plane.

lion air
A Lion Air airplane takes off at Soekarno-Hatta airport in Jakarta, Indonesia, March 18, 2013 Reuters
According to the investigators, the full process ought to have been:

Override the MCAS software.
Press a switch to turn off a motor controlling the angle of the nose.
Press a second switch to confirm the motor shut-down.
Turn a wheel to re-angle the plane's nose and stop the dive.
The plane spent nine minutes in a continuous dive before it hit the sea, according to a report from Reuters which cited investigative sources.


The report said audio from a cockpit recorder showed the pilots working through a technical manual for the plane to find a solution, but that they ultimately ran out of time.

Read more: The Ethiopian Airlines and Lion Air crashes show eerie similarities — here are all the things they have in common

The official investigation into the crash is still underway, and not due to be complete until August 2019.

It has taken on new urgency since a 737 Max operated by Ethiopian Airlines crashed in circumstances officials say are similar to the Lion Air crash.

[J31]

https://www.businessinsider.com/lion-ai ... ort-2019-3

I guess the question is whether the pilots were trained to deal with the situation. I suspect not.

--------------------------------------------------------------------

Pilots in the Lion Air 737 Max crash tried to prevent it by hitting an override switch again and again, unaware there were 3 other steps they needed to take, report claims
Bill Bostock 7m
lion air plane crash debris.JPG
Personnel from Indonesia's National Transportation Safety Board examine debris from the downed Lion Air flight at Tanjung Priok port in Jakarta on November 1, 2018. Beawiharta/Reuters
Pilots on a fatal Lion Air 737 Max flight reportedly hit an override switch dozens of times in a bid to stop them crashing, sources told The New York Times.
According to the sources, the switch turned off software called MCAS, which was wrongly forcing the plane into a dive.
Pressing the switch was the right first step, they said, but needed to be followed by pressing two more switches to turn off a motor which was pointing the plane downward.
The final step, the sources said, was to turn a wheel that would have righted the plane.
The official investigation has yet to return a conclusion. The flight crashed in October in Indonesia, killing all 189 people on board.
The pilots of the Lion Air 737 Max 8 which crashed last year reportedly hit an override switch repeatedly in an effort to save the plane, unaware that they needed to take three further steps

According to sources investigating the crash, who spoke to The New York Times, the pilots flying the Boeing plane pressed a switch meant to suppress a piece of software called the Maneuvering Characteristics Augmentation System (MCAS), which was forcing the plane into a dive.

The plane crashed less than 15 minutes after take-off from Jakarta's Soekarno-Hatta International Airport, killing all 189 people on board.


The sources said that, while the MCAS override switch was the right first move, there were three more steps which needed to be taken to save the plane.

lion air
A Lion Air airplane takes off at Soekarno-Hatta airport in Jakarta, Indonesia, March 18, 2013 Reuters
According to the investigators, the full process ought to have been:

Override the MCAS software.
Press a switch to turn off a motor controlling the angle of the nose.
Press a second switch to confirm the motor shut-down.
Turn a wheel to re-angle the plane's nose and stop the dive.
The plane spent nine minutes in a continuous dive before it hit the sea, according to a report from Reuters which cited investigative sources.


The report said audio from a cockpit recorder showed the pilots working through a technical manual for the plane to find a solution, but that they ultimately ran out of time.

Read more: The Ethiopian Airlines and Lion Air crashes show eerie similarities — here are all the things they have in common

The official investigation into the crash is still underway, and not due to be complete until August 2019.

It has taken on new urgency since a 737 Max operated by Ethiopian Airlines crashed in circumstances officials say are similar to the Lion Air crash.

Maybe lost in translation to English.

The first switch is a normal electric trim switch. In fact there are two switches on the control yoke and are moved forward or aft together to electrically move the horizontal stabilizer providing pitch trim. Moving the control column switches will also override the speed trim and MCAS system as they all drive the same stabilizer trim motor. Then there are two STAB TRIM cutout switches on the center control pedestal. Switching either or both to cutout will remove power from the electric trim motor stopping all electrical trim inputs from the control yoke switches, speed trim and MCAS.

If you have gone that far you can now manually trim the stabilizer using the manual trim wheel with a cable connection to the stabilizer trom jack. It may take upwards of 60 lbs of force to move the manual tim wheel depending on airspeed. It is about 2.5 turns of manual trim for every second of electric trim flaps up. About 5 turns of manual trim for every second of electric trim flaps down.

[Laser Tilt]

Thanks for the further explanation. I read the report as the pilots having used the two STAB TRIM cutout switches on the center control pedestal and then having 2 more steps to go through.

[complexintentions]

It appears that only a Pilot sitting on the jumpseat prevented the fatal outcome of the other 2 events. Even in that event the flight was continued to destination - I guess we're at the point now where Airmanship and Common Sense have completely disappeared.

I can't quite see how anyone other than the crew in question is qualified to decide if a diversion was required. If the aircraft was controllable and flyable how is landing at destination more dangerous than landing at a diversion airport? Would I take a longhaul flight across the ocean or pole with it? No. But there's many factors in a diversion decision and we simply don't have all the information. On it's own, a runaway stabilizer that has been controlled via the NNC procedure does not meet Boeing's criteria for "Must land at nearest suitable airport."

A system that trims then stops then starts again isn't a runaway trim in my book - the fact that Pilots were unaware of MCAS is Criminal Negligence as far as I'm concerned.

The condition statement of the NNC for a runaway stabilizer, ie "Stabilizer Checklist":

"One of these occurs:
•Stabilizer movement without a signal to trim
•The stabilizer is failed"

Seems pretty clear to me that semantics aside, if the stab trim is doing something I haven't commanded, I better do something, in this case the memory items:

1 STAB cutout switches (both).........CUTOUT
2 Do not exceed the current airspeed.

That's it. That's the whole memory drill.

Agree that not informing crews of a critical system's existence or operation is arrogance that should be punished heavily.

[LETUN]

But it was not a simple runaway trim, the first thing that happened was a stick shaker after they retracted the flaps.
The flight that made it to CGK had the stick shaker going for the whole flight! Even after they had cut out the stab.

[FICU]

Regardless if the shaker is going off you know the thrust is set with the proper attitude in day VMC. You should realize you aren't stalling.

If the trim is running nose down and putting you in a dive and you don't want to be in a dive, you should realize there is a problem with the trim. If you can't trim out of the dive, you should realize there is a problem with the trim.

The trim is now trying to kill you. What should you do?

The stab trim cutout switches are checked for position in the first flight, "before start checklist to the line" by every crew, before every first flight of the day every time. They aren't some obscure switches never dealt with unless it's called for in a QRC or NNC. The Captain touches the switches before every first flight of the day.

[boeingboy]

I can't quite see how anyone other than the crew in question is qualified to decide if a diversion was required. If the aircraft was controllable and flyable how is landing at destination more dangerous than landing at a diversion airport? Would I take a longhaul flight across the ocean or pole with it? No. But there's many factors in a diversion decision and we simply don't have all the information. On it's own, a runaway stabilizer that has been controlled via the NNC procedure does not meet Boeing's criteria for "Must land at nearest suitable airport."

Because the stick shaker was wailing away the whole flight. Don't know about you - but I wouldn't need a checklist item to tell me to go back and land.

But it was not a simple runaway trim, the first thing that happened was a stick shaker after they retracted the flaps.

Wrong. They got the stick shaker at rotation. Mcas trimmed nose down after flap retraction.

Yes - it is as simple as a trim runaway. Trim runaway/uncommanded movement is the same thing. They new the trim was giving them issues and trying to trim them into the ground. Again - You don't need a genius to figure out if your airplane is trying to kill you and you can turn it off....do it. Im sorry to those who have great wild ideas about multiple failures at once, confusion in the cockpit and trim so heavy it takes 2 pilots to pull out and you couldn't trim it back... but the flight data clearly shows they knew about it and the problems came one at a time - it was as simple as turning it off. Even if the crews knew about MCAS I doubt - from the data we've seen - that it would have made any difference. A little common sense has to be brought into any situation. Again - this is why we are professional pilots.....Now if you haven't been trained or can barely fly a 172 - then is it the Manufactures fault?

[FICU]

Wrong. They got the stick shaker at rotation. Mcas trimmed nose down after flap retraction.

Is it true that the Lion Air crew retracted the flaps, the MCAS started then they put the flaps out again and it stopped, then they retracted the flaps again and it started once more or is that from another incident?

[Eric Janson]

It appears that only a Pilot sitting on the jumpseat prevented the fatal outcome of the other 2 events. Even in that event the flight was continued to destination - I guess we're at the point now where Airmanship and Common Sense have completely disappeared.

I can't quite see how anyone other than the crew in question is qualified to decide if a diversion was required. If the aircraft was controllable and flyable how is landing at destination more dangerous than landing at a diversion airport? Would I take a longhaul flight across the ocean or pole with it? No. But there's many factors in a diversion decision and we simply don't have all the information. On it's own, a runaway stabilizer that has been controlled via the NNC procedure does not meet Boeing's criteria for "Must land at nearest suitable airport."

They'd just taken off from Denpasar (Bali).

Stick shaker/loss of speed and altitude information on Capt PFD/MCAS activation when flaps raised.

After using stab trim cutout switches they flew all the way to Jakarta like this. At night. Across Java with all the terrain.

This is quite obviously a "get it on the ground as quickly and safely as possible" situation.

You won't see me on a Lion air flight.

[complexintentions]

Fair enough, my mistake in focusing on the Ethiopian crash in the thread title. I read the two accident reports but not the one of the incident flight where they landed safely, I had presumed they continued because the stab cutouts had restored a level of flight control and indications they deemed acceptable. I didn't realize they had stall warnings "throughout the flight" (FlightGlobal). Completely agree that continuing with unreliable airspeed in that scenario was a poor decision. Yowsa. I'm way too impatient to fly a whole sector with a shaker motor buzzing away, even if I know it's spurious.

All of this does though, is once again underscore that by following the longstanding stab cutout procedure, in spite of their poor risk management they had a successful outcome while their colleagues and the Ethiopian daylight VMC departure did not.

[mbav8r]

Does the 37 not have the ability to remove bad information, ie; transfer the good side to the opposite display?
The RJ can transfer an ADC from one side to the other, thereby removing the spurious info. You can also disable the stick shaker.

[ant_321]

The stab trim cutout switches are checked for position in the first flight, "before start checklist to the line" by every crew, before every first flight of the day every time. They aren't some obscure switches never dealt with unless it's called for in a QRC or NNC. The Captain touches the switches before every first flight of the day.

I’ve never heard of a “before start checklist to the line”. With the Boeing SOP’s the switch position is checked in the captains pre flight flow but not backed up with any checklists.

[FICU]

The stab trim cutout switches are checked for position in the first flight, "before start checklist to the line" by every crew, before every first flight of the day every time. They aren't some obscure switches never dealt with unless it's called for in a QRC or NNC. The Captain touches the switches before every first flight of the day.

I’ve never heard of a “before start checklist to the line”. With the Boeing SOP’s the switch position is checked in the captains pre flight flow but not backed up with any checklists.

The Captain calls for the Before start checklist "to the line" after the flows are complete. In our checklist(B737-200 ad 300) we have an item on the checklist for first flight of the day... "Stab trim cutout switches" ... "Normal".

[BTD]

At my airline the stab switches are checked prior to departure for each flight during the cockpit check.

They are not backed up with a checklist. We do have a before start “to the line” but the only thing after the line is anti collision light. It prevents sitting at the gate for 10 min waiting for traffic behind to clear with the anti collision light blinking away. Then you have a long line of vehicles holding for you on the apron roads.

There are many ways to safely fly an aircraft. And many more ways not to.

Btd

[boeingboy]

They'd just taken off from Denpasar (Bali).

Stick shaker/loss of speed and altitude information on Capt PFD/MCAS activation when flaps raised.

Stop spreading misinformation!. Get your facts straight before commenting!!!! This is a major problem with this investigation.

This stick shaker activated on the takeoff roll at rotation. As did the airspeed disagree. Mcas started when the flaps went to 0.

[boeingboy]

Is it true that the Lion Air crew retracted the flaps, the MCAS started then they put the flaps out again and it stopped, then they retracted the flaps again and it started once more or is that from another incident?

Yes - that's exactly what happened to lion air.

[BTD]

https://reports.aviation-safety.net/201 ... MINARY.pdf

This is the PDF link for the preliminary report for lion air. For interested persons it is worth reading rather than asking questions to the message board as it contains factual information.

[boeingboy]

I even posted the FDR data for all to see.....but some people are not interested.

[FICU]

Looking at the report thew crew was able to stop the nose down trim and trim nose up with electric trim. I wasn't sure if nose up trim only stopped the nose down. If they had only put flaps out a second time after the nose down trim started again.

I'm m finding it tougher to believe the Ethiopian accident is identical to Lion Air after the AD was issued and if Ethiopian put as much effort in informing their pilots about dealing with the issues that Lion Air did with their crews.

[boeingboy]

Looking at the report the crew was able to stop the nose down trim and trim nose up with electric trim.

This is what I've been saying all along - The crew was able to more or less maintain their requested 5000 foot altitude for 10 min using the nose up trim. It was not a completely out of control situation. so why not trim up to level and then shut it off?

I'm m finding it tougher to believe the Ethiopian accident is identical to Lion Air after the AD was issued and if Ethiopian put as much effort in informing their pilots about dealing with the issues that Lion Air did with their crews.

It makes it harder to believe when the airline says - Hey this is what happened and if it does run the uncommandrd stab movement checklist...….only to have the pilots say - what the hell is that? as NONE of their crews (Max or NG) have ever been trained on that memory item. Not even in the sim.

The stab trim checklist is a memory item.....why the hell is everyone flipping through manuals?? Has no-one been drilled in this??