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

[sportingrifle]

BML Tech....I think you may be very close to the truth here. Some of the check pilots at my airline gamed it in the sim and ran into just such a situation.

Just speculation on my part, but I am wondering if the knowledge of this scenario is what perhaps caused Boeing/FAA to announce a further delay in the certification of the "fix." The difficulty of returning the trim manually and need to keep the thrust to maintain pitch attitude would open a whole new set of considerations.

[boeingboy]

Come on guys......They airspeed was 250 - 320 kts for most of the flight - it only increased to stuipidly high numbers in the last 5 secs when it nosed over to 40 degrees down.

It actually sounds like they had it mostly under control until that last 2 min or so....I'd really like to know if they turned the system back on. Unfortunately - I don't believe the stab cutout switches are a monitored FDR parameter. They would have to dissect the CVR for the sound of the switches being selected.

[boeingboy]

Just speculation on my part, but I am wondering if the knowledge of this scenario is what perhaps caused Boeing/FAA to announce a further delay in the certification of the "fix."

I don't know what the extra time required is about - but I know when Boeing held an update for all the regulatory agencies and companies to outline the fixes - EASA didn't even show up! Kinda hard to address your concerns when you don't even participate. The jets are not going to be flying again until everyone signs off on it.

Maybe EASA is just trying to help out Airbus with a few more sales.

[Gino Under]

BoeingBoy

You have been quite insistent and smug with your support of Boeing over these accidents and how easy an MCAS event is to deal with. Now that the preliminary report has been released by Ethiopian authorities we hear via press release from Boeing that MCAS was the issue and these two accidents happened despite both accident flight crews following Boeing STAB TRIM RUNAWAY procedures contained in both the MAX FCOM and AD issued in December. I was wondering whether or not you've had an opportunity to reflect on your position now that Boeing state in that same press release that they "own it"?

Gino Under

[LittleNelly]

People seem to be overlooking the fact that the investigators are the OWNERS of the company.. ethiopian is 100% owned by the government of Ethiopia which is an authoritarian regime that ranks as one of the most corrupt in the world.
You can bet the government is directing the investigation clear of their investment.

The fact remains that the trim can be BOTH electronically or manually overridden. And disconnected. The MCAS commanded trim can not override the pilots.


Let's not forget the ECAA in their official report of Egypt air 990 tried to blame flight control problems instead of the obvious pilot suicide that everyone else had determined. Corrupt third world countries have a reputation of skewing reports in their favor.

Wait to see what the NTSB says.

[W5]

Ethiopian Airlines did not agree with the findings of the Lebanese and the BEA in the case of the ET409 near Beirut in 2010.

https://www.flightglobal.com/news/artic ... ax-456515/

[MZUNGO]

link to the preliminary report in pdf


http://www.ecaa.gov.et/documents/20435/ ... d3we2KO-Ao

[Hugh Jasshole]

How is it possible to be a senior Captain at 28? How can you get 8000 hours and be 28? Did he start flying at 10 years old, or were many of his hours made up?

[boeingboy]

BoeingBoy

You have been quite insistent and smug with your support of Boeing over these accidents and how easy an MCAS event is to deal with. Now that the preliminary report has been released by Ethiopian authorities we hear via press release from Boeing that MCAS was the issue and these two accidents happened despite both accident flight crews following Boeing STAB TRIM RUNAWAY procedures contained in both the MAX FCOM and AD issued in December. I was wondering whether or not you've had an opportunity to reflect on your position now that Boeing state in that same press release that they "own it"?

Gino Under

Gino,
I'm sorry - but I see no reason to "reflect" on anything.
First of all - what did you expect Boeing to do? Everyone - including myself - pretty much expected the MCAS to come out as a contributing factor. (There is always more than 1 factor in an accident) To say they "own it" is right - they built it and it has some things that can be improved. Even I have said it needs some fixes.....but it doesn't fatally cripple the jet

Have you actually read Boeings statement and studied the flight data from both accidents?

Two instances have now presented themselves where MCAS activated through (presumably) false air data - and the crew used the stab cutout switches that prevented any farther stab movement...even though the software commanded it. Worked as designed since the 1960's. There is no data yet to say what happened in the final seconds of the Ethiopian flight - and I 'm very interested to see it. The stab trim system is the same as it has been for decades and I can only see 2 possibilities...1) the pilots turned it back on - in which case it was pilot error. This is being widely reported in the media - but as far as I can tell, it has not been officially confirmed----2) there was a fault in the stab trim system and that could have brought down any 737 from the 100 to the 900. I find both scenarios highly unlikely and will wait for more info from the flight recorders to be released.

[Gino Under]

Thanks for that.
I’m hearing this morning that the Ethiopian pilots were unable to use the manual trim following the mayhem and confusion the intermittent nose down trimming caused. Which, if I recall from my 737 days, isn’t normal or as designed. Thoughts?
If this is true, it could be another death knell for the MAX.

Gino

[BTD]

Thanks for that.
I’m hearing this morning that the Ethiopian pilots were unable to use the manual trim following the mayhem and confusion the intermittent nose down trimming caused. Which, if I recall from my 737 days, isn’t normal or as designed. Thoughts?
If this is true, it could be another death knell for the MAX.

Gino

Hey Guys,

Debating these points, it’s worth spending the time to comb through the prelim report.

“At 05:41:46, the Captain asked the First-Officer if the trim is functional. The First-Officer has replied that the trim was not working and asked if he could try it manually. The Captain told him to try. At 05:41:54, the First-Officer replied that it is not working.”

It looks as if they turned the switches back on given the fdr data, however the report doesn’t say it definitively. However if you are in that situation they may not have much of a choice if the trim wheel won’t move and you are unable to overpower the nose Down tendency. If indeed that is the case it looks like the mistake made was that they didn’t trim back to a normal position with the electric trim and shut it off again immediately. I think we need the rest of the cvr transcript before we can determine the workload at this time.

It appears as if the human factors have intersected with mechanical circumstances with tragic consequences. This wasn’t an easy situation, and it appears despite his lack of experience the f.o. was a valuable asset.

Btd
737 max Capt

[tbaylx]

Thanks for that.
I’m hearing this morning that the Ethiopian pilots were unable to use the manual trim following the mayhem and confusion the intermittent nose down trimming caused. Which, if I recall from my 737 days, isn’t normal or as designed. Thoughts?
If this is true, it could be another death knell for the MAX.

Gino

I doubt anything is a "death knell" for the Max. It will eventually be operating again one way or another once the fix is implemented.

Initial reports indicated the crew complied with Boeing procedures, however the preliminary report is quite clear they did not. After getting a stick shaker right after takeoff and other indications that there was either unreliable airspeed or failed aoa in accordance with the Boeing bulletin and QRH the runaway stab memory items should have been completed. The first items are disengaging the automation. The Ethiopian crew tried twice to engage the autopilot before finally succeeding the third time. There is no indication that they ever ran the memory items, though they eventually got to the stab trim cutout.
The FO once tried manual trim but reported back to the captain that it was inoperative for reasons not detailed. For unknown reasons it appears like the stab trim cutout switches were then reengaged at some point and the crew used electric trim to trim nose up again though the report isn't clear on when or why. MCAS then reengaged and pitched the aircraft nose down.
There certainly needs to be more details released to understand what was going on, but one thing is for certain, the crew did not comply with the runaway stab memory items as was initially reported. They did eventually get the stab trim cutout however, showing they did realize what was going on.

[Aviatard]

How is it possible to be a senior Captain at 28? How can you get 8000 hours and be 28? Did he start flying at 10 years old, or were many of his hours made up?

According to Ethiopian Airlines records, the captain has the following flight experience:
 Total hours: 8122
 Total hours in B737: 1417
 Total hours in B737-8 MAX: 103
 Flight time in previous 90 days: 266 hours and 9 minutes
 Flight time in previous 7 days: 17 hours and 43 minutes
 Flight time in previous 72 hours: no flight time
The pilot in command was 29 years old. According to Ethiopian Civil Aviation Authority (ECAA)
records, the Captain’s most recent simulator training experience was September 30, 2018, and his
most recent simulator proficiency check was October 1, 2018. The captain completed the Ethiopian
Aviation Academy on July 23, 2010. A review of the captains training records indicated that he
received his 737-800 First Officer type rating on January 31, 2011 and completed his PIC type
rating for the 737-800 October 26, 2017. 737MAX differences training on 3 July, 2018.

You get 8000 hours in 9 years by flying 266 hours in 90 days.

[ant_321]

How is it possible to be a senior Captain at 28? How can you get 8000 hours and be 28? Did he start flying at 10 years old, or were many of his hours made up?

I’m not sure about the senior part. 8000hrs at 28 is doable. I’ll have about 7500 before I turn 29 at my current rate.

[Ki-ll]

Thanks for that.
I’m hearing this morning that the Ethiopian pilots were unable to use the manual trim following the mayhem and confusion the intermittent nose down trimming caused. Which, if I recall from my 737 days, isn’t normal or as designed. Thoughts?
If this is true, it could be another death knell for the MAX.

Gino

I wonder if the high elevator hinge moment was the issue they encountered while unable to trim manually. It is obvious they have been pulling on the control column pretty hard and the speed was also high since the thrust was set at near 94% the whole flight. I think that’d make it hard to operate manual trim.

[Heliian]

the fact remains that the trim can be BOTH electronically or manually overridden. And disconnected. The MCAS commanded trim can not override the pilots.

Uh, that's the whole problem with the MCAS system. It does not disconnect unless cut off. From what I gather, once the mcas has driven the trim down all the way is that the control forces ARE too strong for the pilots to overcome AND to manually trim it back up requires you to "unload" the control. If you don't have the altitude to push MORE nose down then you are toast.

[Gino Under]

At the speeds the ET Max attained during its fatal plunge, I doubt Manual anything would have saved them. Personally, I think the Max is in a grave. Now we simply wait to see whether or not it gets a burial or a revival. I’m really on the fence over these two accidents but I’m inclined to think the burial is getting more and more likely. This aeroplane will likely need a re-cert and a separate new type rating. Will Boeing spring for that?

A post on Facebook makes clear the uphill battle Boeing faces to regain credibility among the flying public - and not just airlines.

In it, the writer insists he or she will not fly with a certain carrier because it uses the 737 Max 8. Instead, the passenger plans to use an Airbus operator because "computer-controlled planes are not safe".

Now, United had an A320 RTB due to an EFIS failure.

…pass the popcorn.
Gino

[BMLtech]

Perhaps the MAX needed either a revised/enlarged tailplane, or a longer fuselage, to counter the adverse aerodynamic effects of the engine /nacelle combination, but Boeing went for the easy option, artificial aerodynamic enhancement. Not so easy now.
This whole situation is possibly resulting from the limitations of the 60's era analog/cable operated pitch control system. The airbus digital fly by wire system allows aircraft with different flying qualities to be programmed to behave more or less the same in normal law, and includes all of the envelope protections like alpha floor, etc. Goes to show how far ahead the A320 was when it came out.

[FICU]

Both the Lion Air and the Ethiopian crew had full electric pitch trim authority at all times while the stab was powered.

What I dont understand with the Ethiopian crew actions is why they only trimmed nose up to 2.4 units and not back to 4.6 units which is where the stab trim was when MCAS activated. It seems the pilot was using control column back pressure to bring the nose up rather than trimming out the control forces before cutting out the trim. I don't think the auto throttles were ever disengaged and remained at climb thrust.

[FICU]

the fact remains that the trim can be BOTH electronically or manually overridden. And disconnected. The MCAS commanded trim can not override the pilots.

Uh, that's the whole problem with the MCAS system. It does not disconnect unless cut off. From what I gather, once the mcas has driven the trim down all the way is that the control forces ARE too strong for the pilots to overcome AND to manually trim it back up requires you to "unload" the control. If you don't have the altitude to push MORE nose down then you are toast.

There should never be a need to manually trim with the handles from an extreme nose down attitude when you can do it with the electrim trim and once stable then cutout the trim power and you have a managable aircraft that can be trimmed with the handles to a landing.

[rookiepilot]

https://www.cnbc.com/2019/04/05/boeing- ... april.html

BA cutting production:

[Jet Jockey]

I can’t believe the amount of pilots that are defending Boeing and the 737 MAX.

It’s obvious its MCAS system is poorly designed and can lead to crashes.

Now even the CEO of Boeing is admitting to this... check out the video.

Boeing is in deep poo poo and now they are trying to save their name, their badly designed and outdated aircraft.

With the new international task force looking into the MAX’s problems (TC is one of them), I doubt the MAX will be flying anytime soon and if it does it might have to be re-certified.

Time will tell if they succeed.


https://eu.usatoday.com/story/news/worl ... 361880002/

[complexintentions]

Try to keep the arguments rational, not emotional. Your post would be better suited to a hysterical Facebook group.

Every modern airliner uses various forms of augmentation with both hardware and software. MCAS as a concept is sound - flight envelope protections exist as software solutions in multiple Boeing and Airbus types and have for decades. The glaring flaws with this particular implementation seem to be a) the shocking lack of redundancy and fault-tolerance and b) Boeing's lack of transparency regarding it's existence and operating parameters. No one is "defending" Boeing on these fronts. Any defensiveness you detect is just people who still believe in common sense and airmanship and don't blindly trust engineers or machines.

The statements regarding the lack of credibility of the Ethiopian report are entirely consistent with my own experiences with that part of the world. Unfortunately it only serves to further muddy the waters by suggesting that the Ethiopian crew were doomed entirely by the system design in spite of doing everything correctly. Which is a completely premature conclusion, totally inappropriate for a "preliminary report". It's nothing more than the face-saving that is typical when a massive conflict of interest exists.

Or perhaps someone could explain how the stab trim system continued to be electrically operated by MCAS if the stab trim switches were indeed cut off - and remained off?

[FICU]

I can’t believe the amount of pilots that are defending Boeing and the 737 MAX.

I'm not defending Boeing. Poor MCAS education and activation design as has been discussed. I'm trying to wrap my head around how 2 planes crashed in day VMC when the pilots had full electric pitch trim authority and were able to over ride MCAS. The Lion Air crew stopped it once by extending the flaps but then decided to retract them again. The Ethiopian crew cut out the trim power when the jet was in a fairly extreme nose down trim condition and then as a last resort turned the trim back on it seems.

Boeing screwed up most definitely but should 2 Max 8s have been lost because of it?

[sportingrifle]

complexintentions

The speculation, and I can't stress enough that it is only speculation at this point, is that the crew turned the stab cutout switches back on because they were unable to manually trim the airplane as per the Boeing QRH. This is a well known issue with the first generation 737's that seems to have been removed from the NG/Max documentation.

The issue is that at high speed,with full nose down trim and aft elevator, the elevator hinge moments load the jackscrew to the point that manual trimming becomes very difficult to impossible. Certainly by one guy. Previous versions of the AOM made reference to the fact that if two crew members used all their force together they would not break the mechanism! It would be interesting to know if the Max uses the same basic stab/elevator/jackscrew assemblies as the 737 Classic. The speculation is also that they may have been unable to retain pitch control if they reduced power due to the loss of the upward pitching moment of the engines. Unfortunately, the faster the airplane went, the harder the trim would be to move. And this could now be an even bigger issue with the NG/Max. The trim wheels on the NG (and I assume the Max) were made smaller due to the redesign of the instrument panel.

Some of our guys tried to game this in the sim and started to see the thrust/pitch coupling. But without knowing exactly how the sim was programmed, could not determine if it represented the actual handling of the aircraft with an MCASA failure - probably not as nobody knew anything about MCAS when the sim was built. What did surprise the crews that were playing with this, was how quickly and in some ways irreversibly,the situation became overwhelming.

To my way of thinking, the real fix at this point, short of fitting a new wing on the airplane, is to retrofit a full blown FBW elevator and trim control system as installed in the 777/787. New sensors, computers, actuators, and a 3rd hydraulic system powered by a RAT. All stuff "real" FBW aircraft have that this "pretend" FBW aircraft doesn't. Or take off the Leap engines, bolt on some CFM's, and call them NG's. But luckily for Boeing, I don't make the rules.