Ethiopian air lines flight goes down all killed [Archive]

JDNSW

12th March 2019, 06:25 AM

The Max uses much larger engines, set higher and further forward so they don't hit the ground. This changes the handling characteristics, but to avoid need to retrain pilots, they have an automatic stall prevention system that takes input from an angle of attack sensor and pushes the nose down to prevent stalling, regardless of what the pilot does. A malfunction of this system is suspected in the case of the Lion Air disaster - the angle of attack sensor had just been changed, but there seems to be some suspicion that the issue may have been the software, not the sensor.

It was also apparent that the pilot training did not cover how to disable the system, but this information has been widely promulgated since then, and it is unlikely the crew of this flight did not know how to disable it. Of course, it is also possible that it was disabled, and the plane actually stalled.

Two developments in the news this morning. The flight data and cockpit voice recorders have been recovered, and Boeing shares have plummeted. Most operators of the type have grounded them indefinitely, in the case of China, by government order, others by the operators.

bob10

12th March 2019, 07:26 AM

Ethiopian airline Boeing MAX-8 forces plane grounding (https://thenewdaily.com.au/news/2019/03/11/china-grounds-planes-after-ethiopia-disaster/?utm_source=Adestra&utm_medium=email&utm_campaign=PM%20Update%2020190311)

goingbush

12th March 2019, 07:38 AM

well i dont think i would get on ethiopian or lionair, but Boeing, sure.

Boeing, yes no problems , but a 737 MAX8 no way, Lucky there are none with Australian carriers

Hugh Jars

12th March 2019, 07:47 PM

This is how the MCAS works:

•either FCC commands nose down stabilizer to enhance pitch characteristics during steep turns with elevated load factors and at airspeeds approaching stall
•activated without pilot input and only operates in manual, flaps up flight
-the yoke trim switch or STAB TRIM cutout switches will override MCAS input
-the control column cutout switches do no stop electric trimming
•stabilizer incremental commands are limited to 2.5 °; uses A/P trim (0.27 units/sec)
-the function is reset once AOA falls below the AOA threshold or if a yoke trim switch is activated
•if the elevated AOA condition persists, the MCAS function commands another incremental stabilizer nose down command
•in the event of erroneous AOA data, the pitch trim sys. can trim the stabilizer nose down in increments lasting up to 10 sec, but are limited to a 2.5° commanded change per run

Now, the 737 also has a speed trim system, which works automatically during manual flight. For those of us that fly the 737, it looks a little unusual to see the trim spinning after takeoff (without pilot input), but it’s there to make our job a little easier. We see this most during takeoff, climb, or go-around. Typically with high thrust.

I have never seen this in any aeroplane I’ve flown. Usually the pilot actuates the stab trim. Having said that, hearing and seeing the trim wheels spinning after takeoff and during climb to a 737 pilot is normal.

However, the MCAS operates in a similar manner and during periods of high workload (takeoff), perhaps the pilots didn’t recognise it was the MCAS and not the speed tim? Maybe they recognised and trimmed it back out, without realising that if the condition still exists the MCAS will activate again after 5 seconds, and they’re back to square one? This doesn’t assume they were getting erroneous indications on their PFD’s wit one or more faulty alpha vanes.

Both actions can be stopped (momentarily) by operating the stab trim switches on the control yoke. Both can be stopped permanently by operating the stab trim cutout switches (as per the Runaway Stabilizer checklist in the QRH.

Even if the crew disabled the system as described above, I do not believe they could have stalled the aeroplane just because of that. The Max still has the same stall warning system as the other NG’s, that being an aural low speed warning, followed by a stick shaker.

I was chatting to one of our engineers today. He’s rated on the Max.
He showed me data from that aircraft, and for the majority of the time it was below 1000’ AGL. The MCAS does not function with flap extended. And, as far as I know, the Max always uses some flap for takeoff. At 1000’ AGL, the aircraft should still have takeoff flap extended and, assuming there are no obstacles, it would have commenced acceleration around this altitude THEN commenced the flap retraction schedule.
So another question is - was the active FCC getting invalid flap position data, causing the MCAS activate at such a low level?

All I can say is I’m glad I wasn’t there...

JDNSW

13th March 2019, 05:34 AM

Interesting question - unless I am mistaken, this flight departed Addis Ababa airport, which is over 7600ft ASL, and only nine degrees off the equator, so this was taking off in very different circumstances to the Lion Air flight. To put this into a local perspective, it would have been similar conditions to, for example, Mt Hagen - (relatively) hot and high, guessing a density altitude of about 10,000ft.

Presumably the crew was very familiar with these conditions (and so should Boeing be - think Denver), but it does suggest that rather than the MCAS system that is the immediate suspect, anything that degraded performance, especially an engine issue, could easily have narrowed the margin between climbout and stall.

bob10

13th March 2019, 09:20 AM

Pilot training questioned.

Concerns over pilot training raised after deadly Ethiopian plane crash (https://thenewdaily.com.au/news/world/2019/03/12/questions-raised-about-pilot-training-over-ethiopia-crash/?utm_source=Adestra&utm_medium=email&utm_campaign=Morning%20News%20-%2020190313)

bob10

13th March 2019, 06:37 PM

Boeing's 'arrogance' caused crashes - aviation expert (https://www.msn.com/en-au/news/australia/boeings-arrogance-caused-crashes-aviation-expert/ar-BBUHMF2?ocid=spartandhp)

Hugh Jars

14th March 2019, 02:11 PM

We don't even know whether the MCAS was a factor. In any instance, it presents with similar characteristics of a runaway stabiliser, which has a memory item checklist to disable the stabiliser trim.

Regarding the possibility of a stall (as an alternative), there are other aural and visual warnings that, when activated, requite immediate recovery action by the crew.

It's not rocker science...

DiscoMick

14th March 2019, 02:44 PM

weeds

14th March 2019, 02:56 PM

Friends who used to live in Africa said Ethopian Air had the best reputation of any airline on the continent. They used to choose it. So it seems unlikely the airline is at fault. I see Boeing has now grounded the aircraft worldwide.

Humans are involved therefore bit early to be saying the airline isn’t at fault.

In the last three days I’ve done a round trip to China.....five flights, the 737-800, A350 and A320 and pilots performed as they should.......except for the baggage handlers as my bag is still in transit.

DiscoMick

14th March 2019, 04:49 PM

Seems the finger is pointing towards an auto-pilot software problem.

Hugh Jars

14th March 2019, 04:57 PM

Seems the finger is pointing towards an auto-pilot software problem.
Mick, the thing is the MCAS (the alleged culprit) is only enabled when the pilots are manually flying the aeroplane. The software problem (if there is one) would be with the flight control computers (FCC's).

bob10

18th March 2019, 09:05 AM

Info from the black boxes points to both the Ethiopian and Indonesian crashes had a common link.

'Clear similarity' between two air crashes, officials reveal | The New Daily (https://thenewdaily.com.au/news/world/2019/03/18/ethiopia-indonesia-crash-link/)

Eevo

18th March 2019, 09:15 AM

from the link you posted

The automated system, known as MCAS, activates if just one of two sensors mounted on the aircraft’s exterior says the nose is too high

usually these things have 3 sensors and 2 of the 3 have to agree before action is taken (so that 1 faulty sensor wont cause a problem)

DiscoMick

18th March 2019, 09:35 AM

Two of my relatives flew Ethiopian Air over the weekend and lived to tell the tale.

weeds

18th March 2019, 10:57 AM

Two of my relatives flew Ethiopian Air over the weekend and lived to tell the tale.

Bet they were not in a MAX8

DiscoMick

18th March 2019, 11:41 AM

No, they are grounded.
You have to feel for reputable airlines which buy planes like the Boeing assuming they are getting the best for their passengers, and then this happens.
I bet Airbus gets some sales out of this.

Hugh Jars

18th March 2019, 09:32 PM

from the link you posted

usually these things have 3 sensors and 2 of the 3 have to agree before action is taken (so that 1 faulty sensor wont cause a problem)

The B737 has 3 pitot tubes, 2 alpha vanes, and 1 TAT probe.

L alpha vane goes to FCC 1
R alpha vane goes to FCC 2

Only one FCC provides input for the MCAS at any given time. It alternates every flight when the aircraft remains powered. Therefore only one alpha vane is providing data at any one time to the MCAS, therefore no ‘agreement’.

The 3 pitots are totally independent and separate, and also do not require any ‘agreement’ value for any part of the system to function. There is a message for ‘IAS Disagree’ to advise that there is a difference between the captain’s and FO’s airspeed indicators (once again, no effect on other systems), but it does refer you to the Airspeed Unreliable checklist to deal with the problem to troubleshoot the faulty indicator, The third pitot (standby) has no comparator.

Eevo

18th March 2019, 11:49 PM

The B737 has 3 pitot tubes, 2 alpha vanes, and 1 TAT probe.

L alpha vane goes to FCC 1
R alpha vane goes to FCC 2

Only one FCC provides input for the MCAS at any given time. It alternates every flight when the aircraft remains powered. Therefore only one alpha vane is providing data at any one time to the MCAS, therefore no ‘agreement’.

yep, and it looks like that design has failed.

bob10

19th March 2019, 08:02 AM

A faulty sensor , apparently.

Boeing Plans to Fix the 737 MAX Jet With a Software Update | WIRED (https://www.wired.com/story/boeing-737-max-8-ethiopia-crash-faa-software-fix-lion-air/?CNDID=52475003&CNDID=52475003&bxid=MjQ1NjY2MTQzNzIzS0&hasha=38b653f59d8a788d2b8029d349fb05f1&hashb=acd4725d670d172aa9d05ce7f671dc63250efce1&mbid=nl_031819_transportation_top50_list1_p1&source=TRANSPORTATION_NEWSLETTER&utm_brand=wired&utm_mailing=Transportation%20NL%20031819_Top%2050% 20Clickers%20list%20(1)&utm_medium=email&utm_source=nl)

bob10

19th March 2019, 08:17 AM

" black " boxes, how they get the data. Interesting, to a layman like me.

How Investigators Pull Data off a Boeing 737’s Black Boxes | WIRED (https://www.wired.com/story/boeing-737-max-8-ethiopia-crash-black-box-data-lion-air/?CNDID=52475003&CNDID=52475003&bxid=MjQ1NjY2MTQzNzIzS0&hasha=38b653f59d8a788d2b8029d349fb05f1&hashb=acd4725d670d172aa9d05ce7f671dc63250efce1&mbid=nl_031819_transportation_top50_list1_p3&source=TRANSPORTATION_NEWSLETTER&utm_brand=wired&utm_mailing=Transportation%20NL%20031819_Top%2050% 20Clickers%20list%20(1)&utm_medium=email&utm_source=nl)

Hugh Jars

19th March 2019, 08:35 AM

yep, and it looks like that design has failed.

Indeed. A single FCC having control over the MCAS (if, indeed that is the cause) is a really poor design....

JDNSW

19th March 2019, 12:17 PM

But not all that surprising seeing it is an add-on to modify handling that changed due to the changed engine position.

Eevo

19th March 2019, 04:04 PM

now im wondering how the FAA cleared this in the first place

bob10

19th March 2019, 08:01 PM

Apparently, the FAA didn't have people on the ground to oversee the modifications, so passed most of the responsibility to Boeing. Mistake.

Comment: A string of missteps may have made the Boeing 737 Max crash-prone (https://www.msn.com/en-au/news/world/comment-a-string-of-missteps-may-have-made-the-boeing-737-max-crash-prone/ar-BBUWFUU?ocid=spartandhp)

DiscoMick

19th March 2019, 10:02 PM

Boeing 737 Max: US prosecutors investigate plane after fatal crashes

Boeing chief speaks of 'tragic loss' as prosecutors investigate 737 Max planes | Business | The Guardian (https://www.theguardian.com/business/2019/mar/18/boeing-737-max-airplanes-inquiry-us-federal-authorities?CMP=Share_AndroidApp_Copy_to_clipboard )

bob10

21st March 2019, 06:47 AM

Not looking good for Boeing.

Lion Air pilots were scouring handbook in final moments before plane crashed (https://www.msn.com/en-au/news/world/lion-air-pilots-were-scouring-handbook-in-final-moments-before-plane-crashed/ar-BBV1yQn?ocid=spartandhp)

bob10

21st March 2019, 07:23 AM

Possible criminal charges over 737 MAX's certification.?

Pilot Who Hitched a Ride Saved Lion Air 737 Day Before Deadly Crash (https://www.msn.com/en-au/news/world/pilot-who-hitched-a-ride-saved-lion-air-737-day-before-deadly-crash/ar-BBUYXWF?ocid=spartandhp)

JDNSW

21st March 2019, 09:58 AM

Given that this sort of thing (Computer modification of aircraft handling faults) can happen in an environment as safety conscious and controlled as civil aviation - how confident can we be about the safety of 'driver assist' or autonomous software in cars?

87County

21st March 2019, 10:36 AM

Very good question, JD. There have been reports of deaths & damages attributed to self driving cars in "autonomous" mode.

The Unintended Consequences of Algorithms (http://mediashift.org/2017/02/unintended-consequences-algorithms/)

JDNSW

21st March 2019, 06:52 PM

Very good question, JD. There have been reports of deaths & damages attributed to self driving cars in "autonomous" mode.

I have raised this previously in discussion on autonomous vehicles - it is my view that this (and the related legal questions) mean that autonomous vehicles in other than limited circumstances are a lot further in the future than some proponents think.

And even 'driver assist' systems are likely to be a contributor to more accidents than they prevent.

bob10

22nd March 2019, 07:07 PM

A bit late, What? Another example of cost cutting? for what cost?

Boeing to mandate 737 MAX safety feature missing on Lion Air and Ethiopian jets (https://www.msn.com/en-au/news/world/boeing-to-mandate-737-max-safety-feature-missing-on-lion-air-and-ethiopian-jets/ar-BBV55zF?ocid=spartandhp)

Old Farang

25th March 2019, 12:36 PM

The following illustrates what Hugh Jars has posted, especially concerning the trim wheel and how it behaves. Be aware that the stabiliser is a "fully flying" tail plane, and the "elevator" may not have sufficient authority to over come an out of trim condition. NOTE: this is filmed in a Sim and not a B737 Max, but I believe that Hugh will agree that the Max has basically the same layout and functions.

https://www.youtube.com/watch'time_continue=23&v=3pPRuFHR1co

Hugh Jars

25th March 2019, 02:12 PM

Why didn't he press the autothrottle disengage switch twice. Bloody thing flashing away and nobody doing anything about it [bigsmile][bigsmile]

Thanks for posting that, Old Farang[biggrin]. It's sort of how it works in the NG, except you have the added distraction of the speed trim running throughout the initial climb. Perhaps the classic doesn't have that. I haven't flown the classic though.

The way we run memory checklists is a little more regimented than those 2 lads. Nevertheless, they got the stab trim cutout switches, which is most important. The other thing the NG has is a folded handle inside the trim wheels. Now I know why. They had a hard time winding the wheel without it, and when you're talking 50 or more rotations of the wheel to counteract configuration, thrust and speed changes - it's a lot of work.

149594

They are the two guarded switches above the #2 fire switch.

Old Farang

25th March 2019, 02:29 PM

The other thing the NG has is a folded handle inside the trim wheels.
Yes, from what I have read it is still there on the Max. It is apparently well known for whacking you in the knee if left deployed! Maybe why they did not use it?

DiscoMick

25th March 2019, 03:36 PM

Is it right the disengage button can be pushed, but then the sensor problem causes it to reengage?

Hugh Jars

25th March 2019, 04:42 PM

Is it right the disengage button can be pushed, but then the sensor problem causes it to reengage?

There is no disengage button per-se. Just the control wheel switches and the stab trim cutout switches.

If the autopilot is engaged, the MCAS should not activate (A stabilizer runaway can happen at any time). If the autopilot is disengaged and the MCAS senses an impending stall, it will inhibit the autopilot (cannot be engaged).

If the MCAS activates, operating the stab trim switches on the control wheel will momentarily stop the trim running. However, if the condition still exists, the trim may start running again. That is the same as the speed trim after takeoff (runs on its own). So yes, the trim will start running again after a short period.

The above applies whether the MCAS is functioning or malfunctioning.

The only was to stop the stab trim from running in all situations is to operate the stab trim cutout switches (pictured above, and shown in Old Farang's video).

Yes, I've been whacked by that bloody handle in the sim when practising the stab trim runaway procedure. It smarts. I don't know whether the classic has it or not. The lads in the video didn't coordinate the whole scenario very well. Perhaps they forgot to extend the handle?

DiscoMick

25th March 2019, 05:54 PM

Thanks. I don't understand this stuff, so good to hear your explanation.

Hugh Jars

26th March 2019, 09:45 PM

https://uploads.tapatalk-cdn.com/20190326/7ad9d8dc3efcd9735b268779f861567b.jpg
https://uploads.tapatalk-cdn.com/20190326/82e21e46e6f0bbb70cc14f8559528bec.jpg

This is the trim wheel (captains side). The handle is extended in the second pic.

Old Farang

27th March 2019, 12:00 AM

Not sure how much of this may be "fake news", but interesting read anyway:

Ethiopian Airlines Had a Max 8 Simulator, but Pilot on Doomed Flight Didn’t Receive Training On It - The New York Times (https://www.nytimes.com/2019/03/20/world/africa/ethiopian-airlines-boeing.html)

bob10

27th March 2019, 08:45 AM

40 seconds to avoid disaster. Not knowing any thing about the system, I have to take it as read.

Latest testing of Boeing jet finds pilots have 40 seconds to avoid ‘disaster’ (https://thenewdaily.com.au/news/world/2019/03/26/boeing-jet-tests-lion-air/)

bob10

5th April 2019, 06:47 AM

Old Farang

5th April 2019, 11:56 AM

The report by Ethiopian Airlines on the crash.

Ethiopian crew followed procedures - first official crash report (https://www.msn.com/en-au/news/world/ethiopian-crew-followed-procedures-first-official-crash-report/ar-BBVBWiW?ocid=spartandhp)

"The crew performed all the procedures repeatedly...…………………………..

And probably included turning the system off and on repeatedly!

JDNSW

5th April 2019, 11:59 AM

The other factor rarely mentioned about this crash is that it is a long way above sea level - Addis Ababa is higher than anywhere in Australia (2355m, 7726ft). This means that for the same IAS, you are actually moving a lot faster. I noticed this when I was living in PNG - after six months flying out of Mendi (5,680ft) I flew down to Wewak (19ft) for a weekend, and was struck by the fact that, approaching for a landing at the usual IAS, I seemed to be nearly stopped.

This would have meant that things happened a lot faster in this case than they would have at sea level - most importantly, for the same nose down angle and IAS, the ground is approaching faster.

bob10

5th April 2019, 03:53 PM

Yeah, it's not the fall,it's that sudden stop at the bottom.

bsperka

5th April 2019, 05:13 PM

Six Minutes To Disaster: How Ethiopian Air Pilots Battled Boeing Max (https://www.ndtv.com/world-news/we-at-boeing-are-sorry-for-lives-lost-in-737-max-accidents-says-boeing-ceo-2018282)

"One of the "angle-of-attack" gauges read 15.3 degrees, likely an accurate reading for a plane taking off. The other erroneously read 74.5 degrees -- which would suggest a plane pointing almost straight skyward."

Hugh Jars

6th April 2019, 05:22 AM

I don’t think things would have happened any faster at the higher elevation. The aeroplane only knows IAS. The pilots fly IAS, except when dealing with an unreliable airspeed situation (setting a known thrust/attitude combination as part of finding the correct indicating airspeed indicator). But this appears to be a faulty L alpha vane data to flight control computer #1, to the MCAS. I say ‘appears’ because it’s still speculation.
Reports that the crew “switched off” the MCAS are typical media stupidity. It cannot be switched off. The Stab Trim system that the MCAS drives however, CAN be switched off. This is what the Stabilizer (sic) Trim Runaway checklist directs the crew to do. NOWHERE in the checklist does it direct the crew to switch it back on. Switching it back on when effectively the problem is solved puts you into test pilot territory. That’s somewhere you DON’T want to be close to the ground. Sure, operating the Stab Trim manually is physical, and needs to be well coordinated between the crew, but you would be mad to knowingly re-introduce the problem by reapplying power to the system.
Reading the FDR transcript, this appears to be what the crew did towards the end of the flight.

Below is the Stabilizer Trim Runaway checklist.
https://uploads.tapatalk-cdn.com/20190405/76af411b30d4f33fe3622a6dbf13825c.jpg

Below is an amplification of the procedure. My highlighting on the position of the Stab Trim Cutout switches.
https://uploads.tapatalk-cdn.com/20190405/4dd4ffc4918fd7e9e4d0d4d2206e9887.jpg

JDNSW

6th April 2019, 06:10 AM

I don’t think things would have happened any faster at the higher elevation. The aeroplane only knows IAS. The pilots fly IAS.......

Of course. My point was that for a given aircraft attitude (other than level flight) and IAS the higher the density altitude, the greater the rate of climb or, what matters close to the ground, descent. This reduces the time available to fix the issues before the ground intervenes.

The aircrew in this case, being local, would have been very familiar with this, but many of those who are talking about the crash would not be. Some, for example US pilots who regularly fly into Denver would have an idea, but I suspect Addis Ababa regularly gets a lot higher density altitude than Denver - its 2,000 feet higher and 30 degrees closer to the equator.

The one time I flew into Margarima in PNG, which has an altitude of 7800ft from memory, the density altitude was over 12,000ft.

weeds

6th April 2019, 06:14 AM

Out of interest......how easy to it to navigate the manual, find the pages, read and do the action when in a major situation??

I imagine it would be a challenge.

Hugh Jars

6th April 2019, 07:02 AM

Out of interest......how easy to it to navigate the manual, find the pages, read and do the action when in a major situation??

I imagine it would be a challenge.

Hi Weeds,
If you look at the checklist above, everything above the dotted line are what’s called ‘memory items’. They must be performed from memory by the crew without reference to the QRH. There are quite a few of these checklists on the 737. Checklists that must be done from memory are that way because they are flight safety critical and need to be completed in a timely manner. The ‘Engine Fire or Engine Severe Damage or Separation’ checklist is another.

Once the memory items are done (and any other necessary tasks completed) we go back and do the whole checklist from the beginning for 2 reasons: 1. To confirm all the memory items are complete, and 2. to complete the reference items below the dotted line, which contain info of a less urgent nature, such as performance effects of the failure, and effects on the remainder of the flight, such as other systems degraded by the malfunction, and other relevant data. In this case, you stay in this checklist until landing. In other checklists, you might finish it and go back to the normal checklists for the remainder of the flight. It just depends on what the failure is.

Below is an example of running 2 checklists in the B777. The crew deal with an engine fire (all from memory). They only do the memory items of the first checklist as they are unable to extinguish the fire (more important to get the folks off than running through the reference items, which have no effect).
They then run the Evacuation Checklist (read and do - no memory items).

The scenario is similar on all Boeing jets.
YouTube (https://youtu.be/8gIwZiEnULQ)

bob10

6th April 2019, 07:47 AM

Boeing finds second software problem , not associated with the first.

Additional software problem detected in Boeing 737 Max flight control system, officials say (https://www.msn.com/en-au/news/world/additional-software-problem-detected-in-boeing-737-max-flight-control-system-officials-say/ar-BBVFhZU?ocid=spartandhp)

sashadidi

6th April 2019, 08:34 AM

Another analysis.
April 05, 2019, ©. Leeham News: The preliminary accident report of the ET302 crash was released yesterday. It confirmed what we wrote about earlier in the week, the pilots followed the prescribed procedure to stop MCAS. Yet they didn’t make it.

Part of why we presented Wednesday. Here follows additional analysis after studying the information in the Preliminary Crash Report.
Continued here:
Bjorn’s Corner: ET302 crash report, the first analysis - Leeham News and Analysis (https://leehamnews.com/2019/04/05/bjorns-corner-et302-crash-report-the-first-analysis/#comments)

jspyle

6th April 2019, 08:47 AM

Another analysis.
April 05, 2019, [emoji767]. Leeham News: The preliminary accident report of the ET302 crash was released yesterday. It confirmed what we wrote about earlier in the week, the pilots followed the prescribed procedure to stop MCAS. Yet they didn’t make it.

Part of why we presented Wednesday. Here follows additional analysis after studying the information in the Preliminary Crash Report.
Continued here:
Bjorn’s Corner: ET302 crash report, the first analysis - Leeham News and Analysis (https://leehamnews.com/2019/04/05/bjorns-corner-et302-crash-report-the-first-analysis/#comments)I'm sorry for those who lost their lives and cannot imagine the pain that there families and loved ones feel.

I understand that there have been two crashes but have there been instances of successful recovery? Would we ever know?
Those incidents would surely have been reported to Boeing.

bsperka

6th April 2019, 09:22 AM

I'm sorry for those who lost their lives and cannot imagine the pain that there families and loved ones feel.

I understand that there have been two crashes but have there been instances of successful recovery? Would we ever know?
Those incidents would surely have been reported to Boeing.For some reason USA pilots reported similar instances to NASA? One of the reasons I read on why USA stopped them from being flown.

weeds

6th April 2019, 11:26 AM

Hi Weeds,
If you look at the checklist above, everything above the dotted line are what’s called ‘memory items’. They must be performed from memory by the crew without reference to the QRH. There are quite a few of these checklists on the 737. Checklists that must be done from memory are that way because they are flight safety critical and need to be completed in a timely manner. The ‘Engine Fire or Engine Severe Damage or Separation’ checklist is another.

Once the memory items are done (and any other necessary tasks completed) we go back and do the whole checklist from the beginning for 2 reasons: 1. To confirm all the memory items are complete, and 2. to complete the reference items below the dotted line, which contain info of a less urgent nature, such as performance effects of the failure, and effects on the remainder of the flight, such as other systems degraded by the malfunction, and other relevant data. In this case, you stay in this checklist until landing. In other checklists, you might finish it and go back to the normal checklists for the remainder of the flight. It just depends on what the failure is.

Below is an example of running 2 checklists in the B777. The crew deal with an engine fire (all from memory). They only do the memory items of the first checklist as they are unable to extinguish the fire (more important to get the folks off than running through the reference items, which have no effect).
They then run the Evacuation Checklist (read and do - no memory items).

The scenario is similar on all Boeing jets.
YouTube (https://youtu.be/8gIwZiEnULQ)

Thanks for that.....I’d be not good as a pilot as my memory is shot.

bob10

7th April 2019, 03:48 PM

JDNSW

7th April 2019, 07:31 PM

No back up system?

Boeing's 'single point failure': Why was there no backup system on 737 Max jet? (https://www.msn.com/en-au/news/world/boeings-single-point-failure-why-was-there-no-backup-system-on-737-max-jet/ar-BBVGO28?ocid=spartandhp)

This, on the face of it, would seem to be a major problem for Boeing. As two major accidents appear to have demonstrated, the MCAS is a flight critical system. For boeing to have either not recognised this, or recognised it and deliberately treated it as not being flight critical, puts them in a very bad position, highlighted by the fact that the 'AoA disagree' warning system was an extra cost options - and fitted to neither of these aircraft.

All it needs now to really put them in a bad position is for an internal memo to surface warning of this possible outcome. I have seen articles suggesting the root of the problem is the separation of management from engineering and the move of management from Seattle to Cicago, from where the company has been run by MBAs with no production or design experience.

bob10

7th April 2019, 07:38 PM

I have afriend whom is an engineer with Qantas, he has said the moving of engineering to Singapore, is a an equally bad move.

DiscoMick

8th April 2019, 05:35 PM

The Boeing scandal is an indictment of Trump’s corporate America

The Boeing scandal is an indictment of Trump’s corporate America | Will Hutton | Opinion | The Guardian (https://www.theguardian.com/commentisfree/2019/apr/07/boeing-737-max-regulation-corporate-america?CMP=Share_AndroidApp_Copy_to_clipboard)

JDNSW

8th April 2019, 07:36 PM

I don't think it started with Trump, although Trump is the culmination of it. The watering down of government oversight in aviation goes back at least to GWBush, and possibly as far back as Reagan.

cripesamighty

8th April 2019, 08:38 PM

It started around the time the airline industry was de-regulated several decades ago, and this is the culmination of those decisions. Plenty of info online about it.

Windaroo

9th April 2019, 06:06 AM

Have a read of this..

B38M, en-route south east of Addis Ababa Ethiopia, 2019 - SKYbrary Aviation Safety (https://www.skybrary.aero/index.php/B38M,_en-route_south_east_of_Addis_Ababa_Ethiopia,_2019?utm _source=SKYbrary&utm_campaign=b612ce0882-614_Alarming_Story_31_12_2018_COPY_01&utm_medium=email&utm_term=0_e405169b04-b612ce0882-276530305)

bob10

12th April 2019, 07:08 PM

FAA to meet with U.S. airlines, pilot unions on Boeing 737 MAX (https://www.msn.com/en-au/money/markets/faa-to-meet-with-us-airlines-pilot-unions-on-boeing-737-max/ar-BBVR6fb?ocid=spartandhp)

Eevo

16th April 2019, 02:27 AM

https://www.youtube.com/watch?v=H2tuKiiznsY

Tins

16th April 2019, 10:28 AM

This is the first in an excellent, IMO, series of videos on this topic.

https://youtu.be/AgkmJ1U2M_Q

bob10

17th April 2019, 06:41 AM

Thanks for that, very interesting even for a layman like me.

Tins

18th April 2019, 04:43 PM

Thanks for that, very interesting even for a layman like me.

Bob, I have about 30 hours in a PA28 about 33 years ago. So, I'm possibly more of a layman than most here, but aviation is fascinating. I just wish it didn't need mistakes like this to attract interest from the masses.

Also, I hope that Boeing, who deserve the reputation they have built over more than 100 years, don't fall due to this.

Hugh Jars

19th April 2019, 06:35 PM

The opening minute or so of the above video seems to imply that the stabiliser screwjack is to blame, whereas it definitely is NOT.

The screwjack at full nose-down position is not because of a fault or mechanical failure, but is most likely a result of the MCAS driving it there (basically what I have written in previous posts).
If the Stab Trim Cutout switches had been left in the cutout position (as per the checklist), we wouldn't be having this discussion [smilebigeye] However, it appears the crew decided to become test pilots and switch it back on. Yes, the FO said the manual trim could not be moved. Did he extend the handle and try, or did he only try to rotate the wheel on its own? (all but impossible). The manual trim requires a LOT of effort to move. In such a situation, both pilots could have extended their handles and should have been able to move it manually together. It does not appear they tried that, but instead just switched the cutoff switches back on.

JDNSW

19th April 2019, 08:23 PM

The aircraft by that time was well above Vmo - is it still possible to manually trim at that speed, and even if it is, is it possible to do so fast enough when that close to the ground?

donh54

20th April 2019, 06:13 AM

An old (not bold!) pilot told me that the most important mathematical equation in flying is the relationship between a) time to identify and fix the problem, and b) time to impact. Seems to me, that in both cases, the lack of pilot training in the MCAS failure, meant that that equation was weighted too far to one side. Very very sad

Hugh Jars

20th April 2019, 11:27 AM

The aircraft by that time was well above Vmo - is it still possible to manually trim at that speed, and even if it is, is it possible to do so fast enough when that close to the ground?

I’m not sure, but I imagine ‘yes’. The fastest I’ve been when dealing with a runaway stabiliser (in the simulator) is about 330kt. That’s just below Vmo in the -800NG.

We had to do it with one pilot flying and one trimming. The resistance is not that bad, but it’s very tiring because there are a LOT of turns to to get a trim change. I coordinate it in lots of 10 rotations “ten forward.... ten back...” or similar.

The need to trim is greatest as you configure for landing. You need lots of forward trim as you run the flaps out. So typically you would set up on a longer than usual final and start to configure/trim early. We have to be stable by 1000’ AGL. In a situation with manual trimming, I’d want to be stable by 3000-2000’.

From what I understand, they were in the vicinity of 390kt. Another factor which may have exacerbated the problem is mach tuck. That’s when the centre of pressure moves aft with increasing mach number (creating a pitch-down tendency).
That’s only a theory of mine. The 737 has speed trim and mach trim - both of which act through the stab trim, and therefore are inoperative if you switch the stab trim cutout switches to cutout. So it’s possible that if the aircraft had been slowed (within reason, say 250kt) that some of the pitch-down tendency may have been reduced, and given back some pitch control. The last 2 paragraphs are all theorising on my part...

JDNSW

20th April 2019, 01:09 PM

Hugh Jars

20th April 2019, 04:11 PM

According to what has been published, the speed at the time was 360 ->380kts. The trim from full nose down to neutral is 125 turns. I think slowing down was not possible in the circumstances - at that speed even if the elevators were sufficiently powerful, which I gather they are not, the control load would have been impossible for one pilot (the other on the trim).

It seems to me that they were in a virtually unrecoverable situation before they realised it was a serious problem.

Hi John,
What I'm suggesting is twofold: To slow down from such a high speed (without any control input at all) would move the CP forward (reducing the pitch-down tendency from mach tuck). Remember the elevator only provides part of the total pitch force with a fully trimmable stabiliser. Nevertheless, if they did have difficulty with manual trim, slowing down may have made trimming easier (see my last para).

Part of the checklist requires the autothrottle to be disengaged. This probably happened after acceleration altitude when the autothrottle would have set climb N1. I suspect that this is where the thrust stayed throughout the flight. That would partially explain the high speed.

I have sim in a few weeks. One of the scenarios involves a runaway stabilizer. It's been a long while since I did one of these. I'll let you know the effect of airspeed vs manual trim force. I suspect it will be negligible, as the aeroplane is designed to be trimmable throughout the full flight speed range.

John.

Tins

20th April 2019, 07:38 PM

The opening minute or so of the above video seems to imply that the stabiliser screwjack is to blame, whereas it definitely is NOT.

No. He merely states that it has been "widely reported". Also, he relates what the ATSB stated, that the jack screw was in the "full nose down position".

The author of the video is a pilot of possibly more hours than you ( sorry, I have no idea how many hours you have, but he states his in subsequent vids. Maybe you should watch. However, I'll bow to your superior knowledge ), and he goes on to quote the preliminary report at length in his vids. He never blames the jack screw. He blames the poor implementation and initial design of MCAS, in particular the non redundancy of that system. He blames pilot error ( like you say, the switches should have stayed OFF, as Boeing said). He blames poor training for the event of MCAS 'runaway' ( my words ), He describes the problem with the autothrottle in take off mode, and clearly describes the issues all of the above would have created for pilots with only 2,000 ft AGL to work with.

He also describes the difficulty actuating manual trim at the airspeed the aircraft had. As a layman, I can only go with what the people who actually fly the things say. He is one of them, although I believe his currency is on the 777.

And people want self driving cars... If Boeing can't work out automation, you can be damned sure that neither can Google.

Meanwhile, Boeing is losing a reported 70 MILLION a day. Can you still travel to Europe by sea?

JDNSW

20th April 2019, 09:05 PM

Hi John,
What I'm suggesting is twofold: To slow down from such a high speed (without any control input at all) would move the CP forward (reducing the pitch-down tendency from mach tuck). Remember the elevator only provides part of the total pitch force with a fully trimmable stabiliser. Nevertheless, if they did have difficulty with manual trim, slowing down may have made trimming easier (see my last para).

If they could not trim, and control force required prevented lifting the nose with elevator, wouldn't the only way of slowing be to reduce thrust - which I presume would cause some pitch down? In any case, by this stage the nose was well below the horizon, so this may not have made much difference.

Part of the checklist requires the autothrottle to be disengaged. This probably happened after acceleration altitude when the autothrottle would have set climb N1. I suspect that this is where the thrust stayed throughout the flight. That would partially explain the high speed.

Yes, I assume something like that - the control issue clearly had nothing to do with the thrust setting, so there would be no reason to touch it.

I have sim in a few weeks. One of the scenarios involves a runaway stabilizer. It's been a long while since I did one of these. I'll let you know the effect of airspeed vs manual trim force. I suspect it will be negligible, as the aeroplane is designed to be trimmable throughout the full flight speed range.

John.

Thanks. While I have limited experience, never having flown anything with more than one engine, I got my PPL in 1967, and still maintain an interest in aviation, although I have been inactive for nearly twenty years.

Tins

20th April 2019, 09:49 PM

What's scary here is that the aircraft systems clearly fought the pilots. We can argue until we are blue in the face, but the system fought the pilots, and it did so due to apparently faulty inputs. MCAS used data from ONE AOA sensor, and ignored the other, if the preliminary report is to be believed. The 737/8/9 Max is grounded on the basis of the prelim report, and events prior. The MCAS system would seem, on first basis, to be at fault here. Remember, the Ethiopian flight was not the first to crash. MCAS has been blamed for the LionAir Flight 610 crash as well.

Boeing is in very deep ****. So they should be. Airbus have been criticised about their cockpit layout. "Sully" has picked them up over Air France Flt 447, and so he should. He is absolutely correct that stick inputs on one side should be replicated on the other side. 447 proves this.

Boeing has failed us. They have put a system in place that overrides pilots. 189 people died on LionAir 610, and 157 on Ethiopian 302. Boeing is in spin control. It is not good enough.

Old Farang

20th April 2019, 11:06 PM

Remember, the Ethiopian flight was not the first to crash.
There can be no argument that Boeing has a lot to answer for, but as I have posted previously, (not sure if it was on here) there are 350 B737Max in service, of which only 2 have crashed, and it has to be said, both of them in 3rd World countries.

DiscoMick

21st April 2019, 12:19 PM

Where did Boeing's 737 MAX go wrong?
Boeing's billion-dollar bungle has tainted American aviation prestige — how will it recover? - ABC News (Australian Broadcasting Corporation) (http://www.abc.net.au/news/2019-04-21/inside-boeings-billion-dollar-bungle-737-max/10944936)

JDNSW

21st April 2019, 01:27 PM

It has become clear that the issue stems from the design criteria - no new pilot training, extend the current 737 certification (a new design would face a lot more costly and time consuming certification process). It seems to have been allowed to get through as a result of the close relation between Boeing and FAA, but as pointed out, no aviation authority in the world has enough money to technically supervise a company like Boeing.

However, it seems Boeing has failed to maintain the expected level of expertise expected, specifically in designing a flight critical system that depends on a single sensor. While it is unreasonable to expect the FAA to have spotted this, they are tarred with the same brush.

bob10

22nd April 2019, 08:31 AM

Something is inherently wrong with Boeing's work practices. Warning bells must ring when a new factory is opened, and the stipulation is, no union employees. Tales of defective parts taken out of bins and fitted to aircraft to make deadlines , if there is anything 3rd world, that's it.

Boeing 787 Dreamliner: complaints of shoddy work on another jet (https://thenewdaily.com.au/news/world/2019/04/21/boeing-787-dreamliner-complaints/?utm_source=Adestra&utm_medium=email&utm_campaign=Morning%20News%20-%2020190422)

Milton477

22nd April 2019, 10:38 AM

What sort of monkeys have Boeing got writing their control software or whatever you call it in a jet. How can the guy writing not see that a single sensor failure will cause a crash & then not report it/do something about it? Maybe the software is written by committee. I work as a control systems software engineer & something like this would be 'what if'd' to death & tested off line to destruction before it went live. It is completely unfathomable to me that this has been allowed to happened. Somebody or a whole bunch of somebodys need to be locked up for this. Boeing have obviously become blase over their position in the industry & no regulatory body has the means or the will to challenge them.

So much for software to prevent the pilot killing the passengers! Must have been terrifying for the pilots, not to mention the pax.

DiscoMick

22nd April 2019, 12:01 PM

What puzzles me is how Boeing could think it was acceptable to fit bigger engines upsetting the balance of the plane, install a system to automatically push the nose down and then not train pilots or even mention it in the manual. The charitable explanation is sheer incompetence.

JDNSW

22nd April 2019, 12:03 PM

The software writers almost certainly just programmed what they were told to do - they are almost certainly qualified in IT not aerospace engineering. The engineers who designed the system should have spotted the issue, but appear not to have - presumably they did not realise that it was a critical flight system - after all, it just made a minor modification to trim. What seems to have been missed is that it keeps making these trim corrections, and they are cumulative.

The other serious issue is that they offered an "AOA disagree warning" system as an extra cost option. Surely this shows that as a company, they did not realise the issue. Neither of the aircraft involved in these two disasters had this option. I suspect most of the ones flying without incident may have this fitted - which would lead to early detection and rectification of a sensor starting to go bad.

Several accounts suggest the rot set in when they moved management away from manufacturing, and staffed the management with MBAs, who promptly outsourced everything they could. (probably including the IT work!) This would have demonstrated to any competent engineers they hired that there was no career progression available in the company, which can hardly have helped to improve their design expertise.

Eevo

22nd April 2019, 12:36 PM

What puzzles me is how Boeing could think it was acceptable to..

easy. money and sales.

Hugh Jars

22nd April 2019, 01:27 PM

The author of the video is a pilot of possibly more hours than you ( sorry, I have no idea how many hours you have, but he states his in subsequent vids. Maybe you should watch. However, I'll bow to your superior knowledge ), and he goes on to quote the preliminary report at length in his vids.

Hi John. It does't really matter how many hours I have, but since you asked - I've done 25 years in airlines, with around 6000 hrs on the B737 NG... Nevertheless, I don't feel I have superior knowledge to anyone, just sharing my insight and understanding of the type I fly everyday.

I did watch the videos, and most of the info he discusses I had already touched on before the videos were produced. Some info he presented was incorrect (part of which he corrected in subsequent videos, some not). Nevertheless, overall they're quite informative.

He also describes the difficulty actuating manual trim at the airspeed the aircraft had. As a layman, I can only go with what the people who actually fly the things say. He is one of them, although I believe his currency is on the 777.

He has some experience on the B737, but flies the tripler. He's not current on type (B737). I'm current (for what that's worth [smilebigeye]). He describes and demonstrates the difficulty of manually trimming at high speed. There's no evidence to suggest that both pilots had a go at the same time to trim. The 200hr FO just said "it's not working", and they moved on and switched the Stab Trim Cutout switches back on). Whether the trim wheels were recovered (and the position of the manual knobs known) may give some insight as to whether they both had a go. Once again, a crew coordination issue (see below).

What's scary here is that the aircraft systems clearly fought the pilots. We can argue until we are blue in the face, but the system fought the pilots, and it did so due to apparently faulty inputs. MCAS used data from ONE AOA sensor, and ignored the other, if the preliminary report is to be believed. The 737/8/9 Max is grounded on the basis of the prelim report, and events prior. The MCAS system would seem, on first basis, to be at fault here. Remember, the Ethiopian flight was not the first to crash. MCAS has been blamed for the LionAir Flight 610 crash as well.

The MCAS (in its present iteration) did't ignore the other side Alpha Vane - it was designed to only use one side (once powered up), with no redundancy(!). It does switch between L and R FCC's on alternating flights (and following a power-down), but essentially if the Alpha vane data the MCAS is currently using becomes corrupt, there's nothing you can do to revert to a valid source.

The whole system was poorly designed and implemented in the first place. Other posts here reflect the underhandedness and systemic issues of Boeing. They will pay dearly...

The other John (JDNSW)
If they could not trim, and control force required prevented lifting the nose with elevator, wouldn't the only way of slowing be to reduce thrust - which I presume would cause some pitch down? In any case, by this stage the nose was well below the horizon, so this may not have made much difference.
Indeed, John. They absolutely should have slowed down. Reducing thrust and/or deploy the speed brakes may have helped. You're right about the thrust/pitch couple, but remember that slowing down would have:
a) made it easier to trim out the nose-down stab and regain some elevator authority, and;
b) moved the CP forward, possibly mitigating some of the pitching moment (remember, at that speed they were in test pilot territory).

It's noted in the report that the thrust was left at either the takeoff or climb thrust setting. There are two possibilities:
1) They took off without the autothrottle engaged (no biggie. Sometimes it's not available due to an MEL, and we do it semi-regularly), or;
2) They disengaged the autothrottle as part of the Runaway Stabilizer checklist (most likely).
The catch is that with autothrottle disengaged, you lose Vmo speed protection (and other protections), and have to operate the thrust levers manually to ensure your speed remains where you want it. This is probably a crew coordination issue that in the heat of the moment, it appears nobody was in full control of the aircraft. Having a 200hr pilot in the right seat even under normal operations can be quite a challenge (from experience).

Yes, I assume something like that - the control issue clearly had nothing to do with the thrust setting, so there would be no reason to touch it.

That's absolutely the reason they should have reduced thrust (see above).

The other serious issue is that they offered an "AOA disagree warning" system as an extra cost option. Surely this shows that as a company, they did not realise the issue. Neither of the aircraft involved in these two disasters had this option. I suspect most of the ones flying without incident may have this fitted - which would lead to early detection and rectification of a sensor starting to go bad.

Excellent point, John. None of the 737NG's on the civil register in OZ have either the AoA gauge or AoA Disagree monitoring installed, as far as I'm aware. The RAAF may have it on their variants (unsure).

I think the human factors aspect has played a bigger part in the prangs than we know (at the moment). Experience, cockpit gradient, personalities, fatigue, health etc will take some time to be established.

Another John. [smilebigeye]

Tins

24th April 2019, 09:53 PM

Hi John. It does't really matter how many hours I have, but since you asked - I've done 25 years in airlines, with around 6000 hrs on the B737 NG... Nevertheless, I don't feel I have superior knowledge to anyone, just sharing my insight and understanding of the type I fly everyday.

I did watch the videos, and most of the info he discusses I had already touched on before the videos were produced. Some info he presented was incorrect (part of which he corrected in subsequent videos, some not). Nevertheless, overall they're quite informative.

He has some experience on the B737, but flies the tripler. He's not current on type (B737). I'm current (for what that's worth [smilebigeye]). He describes and demonstrates the difficulty of manually trimming at high speed. There's no evidence to suggest that both pilots had a go at the same time to trim. The 200hr FO just said "it's not working", and they moved on and switched the Stab Trim Cutout switches back on). Whether the trim wheels were recovered (and the position of the manual knobs known) may give some insight as to whether they both had a go. Once again, a crew coordination issue (see below).

The MCAS (in its present iteration) did't ignore the other side Alpha Vane - it was designed to only use one side (once powered up), with no redundancy(!). It does switch between L and R FCC's on alternating flights (and following a power-down), but essentially if the Alpha vane data the MCAS is currently using becomes corrupt, there's nothing you can do to revert to a valid source.

The whole system was poorly designed and implemented in the first place. Other posts here reflect the underhandedness and systemic issues of Boeing. They will pay dearly...

The other John (JDNSW)
Indeed, John. They absolutely should have slowed down. Reducing thrust and/or deploy the speed brakes may have helped. You're right about the thrust/pitch couple, but remember that slowing down would have:
a) made it easier to trim out the nose-down stab and regain some elevator authority, and;
b) moved the CP forward, possibly mitigating some of the pitching moment (remember, at that speed they were in test pilot territory).

It's noted in the report that the thrust was left at either the takeoff or climb thrust setting. There are two possibilities:
1) They took off without the autothrottle engaged (no biggie. Sometimes it's not available due to an MEL, and we do it semi-regularly), or;
2) They disengaged the autothrottle as part of the Runaway Stabilizer checklist (most likely).
The catch is that with autothrottle disengaged, you lose Vmo speed protection (and other protections), and have to operate the thrust levers manually to ensure your speed remains where you want it. This is probably a crew coordination issue that in the heat of the moment, it appears nobody was in full control of the aircraft. Having a 200hr pilot in the right seat even under normal operations can be quite a challenge (from experience).

That's absolutely the reason they should have reduced thrust (see above).

Excellent point, John. None of the 737NG's on the civil register in OZ have either the AoA gauge or AoA Disagree monitoring installed, as far as I'm aware. The RAAF may have it on their variants (unsure).

I think the human factors aspect has played a bigger part in the prangs than we know (at the moment). Experience, cockpit gradient, personalities, fatigue, health etc will take some time to be established.

Another John. [smilebigeye]

I thank you for your detailed response, and I reiterate my layman's status here. I take the point about the MCAS not ignoring the AOA input, but surely Boeing must admit that that was a poor design. Well, I guess they have, albeit a little late. As for redundancy, surely a 'disagree' from two sensors is a red flag? Apparently Boeing didn't think so:

"essentially if the Alpha vane data the MCAS is currently using becomes corrupt, there's nothing you can do to revert to a valid source."

Boeing dies right there. What an appalling indictment on what was once the greatest aircraft manufacturer ever. A software glitch... It used to be said, "if it isn't Boeing I'm not going". Sadly, it is now "if it it is a Boeing, I'm not going." What a disaster.

Bring back Concorde, I say. Tongue in cheek. Still, safest airliner ever....

It seems that some airlines, American and SouthWest amongst them, have cancelled flights that would have used the 737 /8/9 Max until mid August. I guess they are hedging their bets against re-certification of that aircraft. It could happen well before that, but maybe it couldn't. The question is, will the public accept the aircraft. My belief is, of course they will. Most people have no idea what they are getting into. I do, but I am interested. Would I fly in a 737 Max? Or wait hours for something else? If the 737 Max is re-certified then of course I'd fly in it.
However, Airbus has been uplifted through all of this. The A330neo will thrive due to this in the Asian market. Sure, not a true competitor to the 737 Max, but tell that to Boeing right now.

Tins

24th April 2019, 10:11 PM

The software writers almost certainly just programmed what they were told to do - they are almost certainly qualified in IT not aerospace engineering.

I seriously doubt that. Boeing just doesn't hire Silicone Valley geeks; well, they used not to. If they have then they deserve the ****storm they have coming. If Boeing compartmentalized to the extent you suggest then they will be ****ed in the courts and will die. The US court system is unforgiving, lobbyists notwhistanding. The forthcoming lawsuits are going to be massive, and bear in mind that it is reported that Boeing are losing $70 MILLION a day every day the 737 Max is grounded. It's unsure that Boeing will survive. That , of course, would be tragic.

Old Farang

24th April 2019, 10:24 PM

I think the human factors aspect has played a bigger part in the prangs than we know (at the moment). Experience, cockpit gradient, personalities, fatigue, health etc will take some time to be established.
Absolutely! Boeing can be rightly criticised all day long. But in the end it comes down to a simple fact "fly the bloody aircraft"! Supposedly qualified pilots that it appears didn't do that. The only thing that I would concede is the fact the problem occurred at low altitude, and in the case of not reducing thrust it would be a very hard move as the already nose down attitude would drop further.
But then I am not qualified to comment because I used to fly helicopters, and that is an entirely different ball game.

JDNSW

25th April 2019, 06:22 AM

I seriously doubt that. Boeing just doesn't hire Silicone Valley geeks; well, they used not to. If they have then they deserve the ****storm they have coming. If Boeing compartmentalized to the extent you suggest then they will be ****ed in the courts and will die. The US court system is unforgiving, lobbyists notwhistanding. The forthcoming lawsuits are going to be massive, and bear in mind that it is reported that Boeing are losing $70 MILLION a day every day the 737 Max is grounded. It's unsure that Boeing will survive. That , of course, would be tragic.

Boeing, since the MBAs started to run the company, and moved management away from production, have apparently been outsourcing everything they can. Presumably this includes as much software development as possible. And even if the software developers were still in house, expecting to be laid off at any time hardly improves the quality of the code.

JDNSW

25th April 2019, 06:29 AM

Absolutely! Boeing can be rightly criticised all day long. But in the end it comes down to a simple fact "fly the bloody aircraft"! Supposedly qualified pilots that it appears didn't do that. The only thing that I would concede is the fact the problem occurred at low altitude, and in the case of not reducing thrust it would be a very hard move as the already nose down attitude would drop further.
But then I am not qualified to comment because I used to fly helicopters, and that is an entirely different ball game.

While it is very likely that a better crew could have managed the situation (and there is emerging evidence that some crews have, for example the immediate previous flight of the Lion Air hull), the simple fact remains that the model was sold as needing no further crew training compared to existing 737s, and the crews involved have not been crashing these (not twice in a few months in identical circumstances, anyway) previously. And the worldwide grounding of the aircraft suggests that aviation authorities agree.

DiscoMick

25th April 2019, 11:00 AM

Certainly appears that systems which were optional and not fitted to the crashed aircraft should have been compulsory and standard.
Airbus will puck up a lot of orders from this, I expect.

JDNSW

25th April 2019, 09:00 PM

Problem with that is Airbus have a long backlog of orders, and stepping up their production rate is not something that can be done overnight.

DiscoMick

30th April 2019, 05:14 PM

cripesamighty

30th April 2019, 05:40 PM

His comments are not surprising. Boeing are in major damage control mode and this is par for the course. Similar comments for the attempted covering of butts were uttered by senior VW personnel in relation to the dieselgate scandal. At least 5 of those VW personnel have been charged and are now facing jail time if convicted.

DiscoMick

30th April 2019, 06:32 PM

I imagine Boeing will be sued for billions by relatives of dead passengers, so he has to defend the company.

Tins

30th April 2019, 09:22 PM

YouTube (https://youtu.be/KB4lCbT5oX8)

Tins

30th April 2019, 09:25 PM

YouTube (https://youtu.be/KB4lCbT5oX8)

Or:
https://youtu.be/KB4lCbT5oX8

Hugh Jars

30th April 2019, 09:28 PM

It appears the chairman of Boeing is a liar.

Boeing boss rejects accusations about 737 Max jets that crashed

Boeing boss rejects accusations about 737 Max jets that crashed | Business | The Guardian (https://www.theguardian.com/business/2019/apr/29/boeing-boss-rejects-accusations-about-737-max-jets-that-crashed?CMP=Share_AndroidApp_Copy_to_clipboard)

There are some reporting errors in that piece. Nevertheless, the AoA indicator and AoA Disagree system are indeed optional. None of our aircraft have them, and neither do I believe do QF’s. So he’s telling porkies...

Tins

30th April 2019, 09:52 PM

Nevertheless, the AoA indicator and AoA Disagree system are indeed optional.

As I have said before, I am a layman here, but to me that particular piece of information is evidence of an unconscionable error
from Boeing. Something as basic as that, especially in a new system as the MCAS system was in this aircraft, should be mandatory, not optional. What would it cost as opposed to the entire cost of the aircraft, and now of course as opposed to the entire cost to Boeing altogether, which is probably incalculable, but may possibly cost Boeing everything, is minor in the extreme.

It's easy to second guess, and that is what a lot of us are doing here, but a hell of a lot of us need to trust Boeing, and maybe it's time for the engineers take precedence over the accountants; you know, the way it used to be.

Hugh Jars

2nd May 2019, 07:03 AM

As I have said before, I am a layman here, but to me that particular piece of information is evidence of an unconscionable error
from Boeing. Something as basic as that, especially in a new system as the MCAS system was in this aircraft, should be mandatory, not optional. What would it cost as opposed to the entire cost of the aircraft, and now of course as opposed to the entire cost to Boeing altogether, which is probably incalculable, but may possibly cost Boeing everything, is minor in the extreme.

It's easy to second guess, and that is what a lot of us are doing here, but a hell of a lot of us need to trust Boeing, and maybe it's time for the engineers take precedence over the accountants; you know, the way it used to be.

Fitting, or more appropriately - enabling the system at aircraft build would probably only add a few thousand to the cost (remember most of the hardware is already there). When you’re talking little change out of $100m per aircraft, it really is nothing in the big scheme of things.
Makes you wonder why?

Hugh Jars

4th May 2019, 04:56 PM

A little more info. I'm loath to blame out-and-out pilot error, as these things are always the result of a whole bunch of factors. The link does work.

Access to this page has been denied. (https://seekingalpha.com/instablog/398764-vaughn-cordle-cfa/5290930-boeing-737-max-8-crashes-case-pilot-error?fbclid=IwAR33BADvjho_ff8pP4PsZ78USAk8dcE12gJ xqiTdtjJzkuYHYM9SfIVCgro)

3toes

4th May 2019, 05:43 PM

Fitting, or more appropriately - enabling the system at aircraft build would probably only add a few thousand to the cost (remember most of the hardware is already there). When you’re talking little change out of $100m per aircraft, it really is nothing in the big scheme of things.
Makes you wonder why?

Have seen trucking companies penny pinch on kit on basis every penny saved on price equals lower operating cost and hence competitive advantage.

Anything optional has to be justified before purchase and the difficulty in doing this makes it not worth the hassle as senior management has already made their opinion clear that the product is safe as the manufacturer would have made in mandatory is it was required

JDNSW

4th May 2019, 07:25 PM

Hugh, that looks like a very good summary of the situation. As you say, the crashes cannot be blamed solely on pilot error (or systematic airline procedures error - the Lion Air earlier problems should have prevented the crash, even with the piloting deficiencies).

But the author of this piece has taken the viewpoint "the major contributing factor to these accidents was pilot error". It would be equally valid to consider that since the proposed changes to MCAS software would prevent the occurrence of any similar crashes, "the major contributing factor to these accidents was the design and implementation of the MCAS", and it should have been designed that way in the first place. In reality, for the crashes to happen required both factors to be present (and others including the failure of Lion Air systems to get the aircraft grounded before the flight as a result of previous issues).

I am sure you are well aware of the "Swiss Cheese" model for aviation safety.

DiscoMick

6th May 2019, 06:46 PM

BradC

6th May 2019, 07:53 PM

Boeing knew about 737 MAX problems months before 2018 Lion Air crash, but didn't tell FAA
Boeing knew about 737 MAX problems for months, but didn't tell FAA until after 2018 Lion Air crash - ABC News (Australian Broadcasting Corporation) (http://www.abc.net.au/news/2019-05-06/boeing-knew-737-problems-before-lion-air-ethiopia-crashes/11084326)

There's another from the WSJ attached to this post along similar lines.

If I'm reading that right the AOA disagree alert was supposed to be a standard feature that just didn't work out of the box. The article appears to state the "AOA disagree" indicator was standard but only worked when the "optional" AOA indicators were provisioned.

150680

Eevo

7th May 2019, 01:18 AM

do you think the FAA should be held liable for this?

BradC

7th May 2019, 08:45 AM

do you think the FAA should be held liable for this?

If that question was for me then the answer is "I don't really know". I'm more interested in the final reports and investigative outcomes.

I'm not much for apportioning liability or even speculating as I don't know enough to claim a fully formed opinion.

What I will say is it appears both disasters could have been averted by either better trained and more experienced pilots *or* aircraft that didn't have a pathological system fault.

JDNSW

7th May 2019, 02:12 PM

If that question was for me then the answer is "I don't really know". I'm more interested in the final reports and investigative outcomes.

I'm not much for apportioning liability or even speculating as I don't know enough to claim a fully formed opinion.

What I will say is it appears both disasters could have been averted by either better trained and more experienced pilots *or* aircraft that didn't have a pathological system fault.

As with most aviation accidents, the end result needed several factors to be present, in this case including a seriously deficient aircraft system and insufficient pilot experience and/or training, but also a lack of oversight by FAA, poor management decisions by Boeing, poor maintenance management and fault and incident reporting by Lion Air (and, I expect, Ethiopian and probably other operators).

It is clear to me that the liability is widely shared, although it will be interesting to see where the court decisions land. (Probably take years!)

JDNSW

7th May 2019, 03:28 PM

The recent Moscow Superjet accident is another example of an accident with multiple contributing factors clear even at this early stage. From what we have heard so far the flight had an incident, possibly a lightning strike but possibly an electrical issue, shortly after takeoff, that resulted in a return to the airport. According to one account, they were out of contact, although their transponder said there was an emergency. It is unclear whether they had a landing clearance.

Apparently the lack of communications and perhaps urgency to land led to landing without dumping fuel, so it may have been landing at above maximum landing weight. The combination of this weight and possibly handling errors (by the relatively inexperienced captain) and weather led to the collapse of the main gear, followed by fuel tank rupture and fire. So what was the "cause" of the accident?

Hugh Jars

14th May 2019, 12:49 PM

I don't believe the SS-100 has a fuel dump capability. It's about the same size as the Embraer 190 I used to fly. The B737 doesn't either. I imagine they would be similar (procedurally) with overweight landings (immediate return to land) - it's certainly a consideration, but not a limitation. Provided your landing performance data for the proposed runway is valid, just run the Overweight Landing Checklist and let the engineers do an inspection once back on the ground. Of course, time permitting you would go somewhere and hold to burn off sufficient fuel to get below MLW. In the B737-800 the difference is about 13T if departing at MBRW. That's a lot of holding!

For an uncontained engine fire you have about 15 mins to complete your checklists, set up for the return, get the cabin crew to prepare for an emergency landing/evac etc, before you're facing catastrophic structural failure from the fire. Concorde took less than 2 mins. If the departure airport is doing instrument approaches, it will take you most of that time to get back (if under radar control). If it's visual, you could get it back in 5-7 mins with everything abbreviated.

With the Moscow prang and no-comms, I suspect the crew were concentrating on working the problem and simply ignoring ATC until ready to talk to them. The old analogy 'aviate-navigate-communicate' springs to mind. I remember I had an engine failure about 12 years ago late on descent into Sydney. The first officer was pilot flying and I was doing the radios and managing the problem. We got to the point where I gave them the PAN call and all the information they needed for our arrival. I wanted to continue with the remainder of our checklists and get set up for the approach and landing. Every time I would get part way into it, ATC would interrupt and ask me for more (unnecessary IMO) questions. In the end I said something like "We're very busy here completing checklists and preparing for landing. Give me a heading I can fly for 5 mins uninterrupted and don't call me unless it's important. I'll call you when we're ready to continue". He was a bit miffed, but basically when something like this is going on, you don't want any outside interruptions unless absolutely necessary in the interest of safety. The Moscow crew probably just didn't verbalise it. I'm not criticising ATC. They do a fantastic job. Sometimes they need to realise they are not our priority in a non-normal situation.

An example of excellent controlling is one occasion we had a smoke/fumes in the cabin out of Melbourne at about 20000' climbing out (almost your worst nightmare). We got our initial actions done, told ATC what they needed to know (again) and said we require an immediate return to land. He was onto it straight away. He coordinated with the other controllers and basically said "all runways available - where do you want to go?". I told him where we wanted to go, and he made it happen. Minimum of fuss. Minimum radio disruptions. We were airborne a total of 20 mins. Felt like an hour.

I think the FAA must share some responsibility for what Boeing has done. I haven't seen many industries where self-certification (effectively what FAA allowed Boeing to to) actually works for the end-user/buying public. Look at the caravan industry - it's full of charlatans producing overpriced, under quality products. The data on the compliance plate in most instances, particularly weights, are a fairytale.

Fox and hen house springs to mind.

John.

Tins

15th May 2019, 02:13 PM

I don't believe the SS-100 has a fuel dump capability. It's about the same size as the Embraer 190 I used to fly. The B737 doesn't either.

Could you clear something up for me? I have read elsewhere that short and medium haul airliners do not have fuel dump capability at all. Only long haul. Is that true in all cases?

JDNSW

15th May 2019, 03:29 PM

Thanks again for your explanation Hugh. Reminds me of the one really serious in-flight emergency I have faced while PIC. (not including the Bonanza with electrical failure leading to hand-cranked gear extension!)

This was flying a Grumman AA-5 from Lilydale to Dubbo - over The Rock it dropped a valve. My immediate thought was I'd lost a prop blade, but quickly realised the vibration was power dependent not rpm dependent, and I managed to stretch the glide to do a straight in landing at Wagga. Communications were not exactly top priority, especially since the panel was shaking so violently that changing channels was not feasible. Lesson - in a single, plan as high as possible - gives you more choice if the fan stops.

Tins

15th May 2019, 04:57 PM

Hugh Jars

15th May 2019, 06:21 PM

Could you clear something up for me? I have read elsewhere that short and medium haul airliners do not have fuel dump capability at all. Only long haul. Is that true in all cases?

Hi John,
It’s more determined by the manufacturer/variant, I think, rather than a hard and fast rule.

Old Farang

15th May 2019, 06:57 PM

Hi John,
It’s more determined by the manufacturer/variant, I think, rather than a hard and fast rule.

Hmm, pre-grey hair studies on this one! It is entirely a structural consideration, and SHOULD be determined during design and certification.
As a general rule most narrow body types do not have a fuel dumping system.

Not all planes are equipped with this sophisticated system, however. FAA spokesperson Alison Duquette says that narrow-body planes, like the Airbus A320 or the Boeing 757, aren't built with fuel dumping abilities. But larger, wide-body planes, like the Boeing 777 and 747, which have added tanks, can dump fuel. In fact, the FAA requires certain planes to have fuel jettison systems

Also, before somebody wonders, the dumping is via a "standpipe" in the tanks that protrude well above the bottom of the tank, so not all the fuel can be inadvertently dumped.

JDNSW

15th May 2019, 07:56 PM

Clear weather over the Kilmore Gap, I presume?

This was thirty years or more ago, and I'm afraid I can't remember the weather in the Melbourne area. It is unlikely I would have flown via Kilmore from Lilydale though - except in low cloud conditions my first navigation point would have been Alexandra - flying VFR I tended to fly a great circle when possible. I remember the weather at The Rock - clear, and I was at 9,000ft.

Tins

15th May 2019, 09:28 PM

This was thirty years or more ago, and I'm afraid I can't remember the weather in the Melbourne area. It is unlikely I would have flown via Kilmore from Lilydale though - except in low cloud conditions my first navigation point would have been Alexandra - flying VFR I tended to fly a great circle when possible. I remember the weather at The Rock - clear, and I was at 9,000ft.

Thanks. Flying north(ish) out of LIL would usually take you out over the Kilmore Gap, which isn't at Kilmore btw. A few aircraft have been lost by flying up the wrong path, mistaking the valleys. *VFR is the usual culprit*, combined with low cloud ceiling over the 'mountains'. LIL was my training area, and I was warned countless times. A ceiling of 1,500 is not uncommon. Nor is visibility up to the stars. 1,500, however, is a reason not to fly, but people still do.

I regret that I didn't keep flying. It's an experience I will not forget. But I've never been good with money, and money is needed to fly.

*I need to qualify. VFR isn't the culprit, it is how people make decisions based on it that is. I've heard pilots debating whether it's 'worth the risk' to fly out of LIL going north. Sometimes they find that it is. Sometimes they don't. I don't mean to describe the GDR north of Lilydale as some sort of local Bermuda triangle, but it is dangerous, mostly due to complacency. In recent years there haven't been many light aircraft losses there. Let's hope that trend continues.

JDNSW

16th May 2019, 06:30 AM

I flew out of Lilydale for over twenty years, so I am quite familiar with the area. Normal route would be Glenburn gap if cloud prevented a direct route over the west flank of Mt St Leonard. On the other hand, I remember spending half a day on the ground at Mangalore (with about a dozen other planes, including an F-27), waiting for the fog to clear south of the ranges on my way back. On that occasion I did fly via Kilmore gap, as it lifted leaving a marginal gap under it.

superquag

29th May 2019, 10:53 PM

Old Farang

29th May 2019, 11:08 PM

"Fly
" helicopters ? I thought the Prisoner *negotiated* with 2,319 moving parts to move together in a desired direction...
Ah, but it was a very old helicopter with only 2,150 parts as some parts had been shot off. [bigsad]

sashadidi

2nd June 2019, 01:40 PM

Boeing Built Deadly Assumptions Into 737 Max, Blind to a Late Design Change

Boeing Built Deadly Assumptions Into 737 Max, Blind to a Late Design Change - The New York Times (https://www.nytimes.com/2019/06/01/business/boeing-737-max-crash.html)

Hugh Jars

14th July 2019, 08:47 PM

I mentioned that I was going into the simulator this week, and that I would follow-up on the Runaway Stabiliser.

Mention was made in this thread about the manual trim being difficult/impossible to operate.

We went through the exercise and found that whenever there is an air load on the stab, ie holding a LOT of up elevator against the out of trim situation, the trim is very difficult (but not impossible) to rotate. If the pilot flying reduces his stick-force, that reduces the air load on the stabiliser, and the wheel rotates freely.

So that is now being a recommended technique for manual trimming in all circumstances on all variants.

JDNSW

15th July 2019, 05:25 AM

........
So that is now being a recommended technique for manual trimming in all circumstances on all variants.

But reluctance to do so is perhaps understandable when the MCAS has pitched the nose down and you are close to the ground!

PhilipA

15th July 2019, 07:44 AM

One thing is that they will be the safest and most tested plane ever to be developed once they are back in service.
I think the US authorities are a bit over the top after being embarrassed by their slackness.
I will be happy to fly in one!
Regards Philip A

Hugh Jars

16th July 2019, 08:49 AM

But reluctance to do so is perhaps understandable when the MCAS has pitched the nose down and you are close to the ground!
Yes, but when you're working the problem you try whatever you can, especially if a ground contact is on the cards. We do a lot of facilitated learning and prior to the exercise, the checkie talked about simple aerodynamics and air loads, etc, (without telling us to try reducing the elevator input).

As we went through the sequence, I thought it out and got the FO to try and wind the stab trim once all the automatics were disconnected (which he could, even with the maximum up-elevator that I could physically hold) but it did require some effort on his part. I just eased off the stick force a little as old mate was winding and he communicated that it was much easier. You only need to reduce the pressure-not release it. The rate at which the FO could now rotate the trim was sufficient to restore a controllable and almost in-trim state with a minimal loss of altitude. Fine-tuning the trim from there was easier, but still a crew coordination exercise.

Reducing thrust and airspeed also made the whole exercise easier. We got up to about 300kt initially in level flight as the fault was introduced as we were levelling off (26K full climb thrust with no derate). That's why it's imperative to get the autothrottle out and minimise an airspeed increase.