Boeing 737 Max8 Aircraft Crashes and Investigations [Part 2] 44

[Alistair_Heaton]

This thread is a continuation of:

thread815-445840


****************************
Another 737 max has crashed during departure in Ethiopia.

To note the data in the picture is intally ground 0 then when airborne is GPS altitude above MSL. The airport is extremely high.

The debris is extremely compact and the fuel burned, they reckon it was 400knts plus when it hit the ground.

Here is the radar24 data pulled from there local site.

It's already being discussed if was another AoA issue with the MCAS system for stall protection.

I will let you make your own conclusions.

 

[waross]

Thanks for the link, VE1BLL.
He says pretty much what I have been thinking from a problem solving point of view.

Hi Mike. When you say cowboy, I think rodeo.
The very top rodeo cowboys make a fortune, that, wisely invested, can leave them set for life.
I personally know an ex Canadian champion roper who still enjoys the fruits of his invested earnings, over 25 years later. My son played hockey and branded calves with his sons over the last couple of years.
Some rodeo cowboys make a living.
Some struggle to make a living and a lot often don't recover their entry fees.
This comment, Mike, " which for a time was useful to a now former employer," would put you in the well above average category of 'Cowboy Coder'.
To follow the rodeo comparison, I've got to wonder if some of the 'Cowboy Coder's are making their entry fees.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[MikeHalloran]

Bill, I will take "well above average" as a compliment; thank you for that.

That former employer had ~5000 employees scattered around the globe. I was one of maybe 50 "Champions", selected by the Chairman and primary owner to work on special projects for the Chairman, in addition to their normal duties for a huge bureaucracy. Products generated by the bureaucracy were mostly expensive failures. Successful products just sort of appeared one day, high up in the bureaucracy's product development queue, with no apparent history, all development work having been completed outside, or inside with stolen resources. It was a grand adventure, and worked well until the Chairman got sick and died.



Mike Halloran
Stratford, CT, USA

 

[waross]

Warning: May be off topic.
Yes Mike, a "well above average" compliment.
There are cowboys and there are cowboys.
Coding is not the only field where "Cowboy" is used as a pejorative.
But I know the families of two cowboy brothers.
One is working as a successful professional cowboy.
His brother is almost as good.
Along the way, both have college educations and both have earned teachers certificates.
The othr brother is teaching school locally.
They are not the only "cowboys" with college degrees.
There are a number of schools offering 'rodeo' scholarships.
A successful rodeo cowboy must have above average physical abilities.
People with above average physical ability very often have above average mental ability.
I am pleased that my son has met and been befriended by a number of cowboys who are also successful businessmen and often have an advanced education.
I see a champion cowboy with a college degree on the side, as a positive role model.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Alistair_Heaton]

From Reuters

"
By David Shepardson

WASHINGTON (Reuters) - The U.S. Federal Aviation Administration said Friday that a joint governmental review of the now grounded Boeing 737 MAX will begin on April 29 and will include 9 other aviation regulators from around the world.

The FAA said earlier this month it was forming an international team to review the safety of the aircraft, grounded worldwide following two deadly crashes - in Indonesia in October and in Ethiopia last month - that killed nearly 350 people.

Boeing has announced a planned software update on the 737 MAX to prevent erroneous data from triggering an anti-stall system known as MCAS that is under scrutiny following the two disastrous nose-down crashes. It has not yet submitted the software to the FAA for formal approval.

China, the European Aviation Safety Agency, Canada, Brazil, Australia, Japan, Indonesia, Singapore and the United Arab Emirates will all take part, the FAA said, in the Joint Authorities Technical Review (JATR) that is set to last 90 days, the FAA said. Most of the countries previously confirmed they would take part.

The JATR is chaired by former National Transportation Safety Board Chairman Chris Hart and is comprised of a team of experts from the FAA, NASA and international aviation authorities. The group will conduct a comprehensive review of the certification of the aircraft’s automated flight control system.

The team will evaluate aspects of the 737 MAX automated flight control system, including design and pilots’ interaction with the system, "to determine its compliance with all applicable regulations and to identify future enhancements that might be needed," the FAA said.

Hart told reporters earlier this month the review is in response "to the growing need for globalization ... because these airplanes are all over the place" and to the need for a “uniform response."

American Airlines and Southwest Airlines Co have canceled flights into August as a result of the grounding.

Boeing Chief Executive Dennis Muilenburg said Wednesday the manufacturer is making "steady progress" on the path to certifying a software update to the grounded 737 MAX and has made the final test flight before a certification flight."

I susepct though they may dig up other issues as well in the process.

 

[waross]

That may not be as good as it sounds.

The team will evaluate aspects of the 737 MAX automated flight control system

Why do we have MCAS in the first place?
I'm sorry. That question is outside the terms of reference of this inquiry.

Remember the Piper Alpha?

An explosion and resulting oil and gas fires destroyed Piper Alpha on 6 July 1988, killing 167 people,
The total insured loss was about £1.7 billion ($3.4 billion)

I was on a project when the project manager dictated that we would NOT be using locks on switches.
A paper lockout system would be used.
I suggested that the Piper Alpha disaster could have been avoided by the use of a $5.00 padlock on a motor starter rather than a paper lockout system.
The project manager denied this and provided me with a url to what he claimed was the official inquiry.
I found the report online and in the first paragraph found words to the effect:

The purpose of this inquiry is to investigate the 'domino effect' where one problem led to another, and help develop standards for the layout of future platforms with a view to avoiding similar disasters in the future.
This inquiry will not investigate the root cause of the disaster.
No need to read further.
With 3.4 billion in insured loss in the balance you can expect some powerful lobbying and pressure when the terms of reference are set.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Alistair_Heaton]

Actually Les one of the Piper OIM's that was killed on the RIB pulling people out the water was my Scout master. There was quiet a few kids without dads that week at school in Aberdeen.

I also taught one of the guys that jumped from the helideck and survived how to fly.

But more similar to this situation is the Chinook crash off Shetland. A change in transmittion component without suitable testing and analysis led to its failure and desyncing of the blades.

Here is the Cullen inquiry reports if you want.

http://www.hse.gov.uk/offshore/piper-alpha-disaster-public-inquiry.htm

And the accident report on the chinook

https://www.gov.uk/aaib-reports/2-1988-boeing-vertol-bv-234-lr-g-bwfc-6-november-1986

 

[IRstuff]

One of the results of Five Whys is listed the executive summary, a failure of a process; communications, documentation, and following existing process/documentation.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[waross]

Alistair; I apologize for triggering what must still be painful memories.
Thank you for sharing the links.
I have spent some time reading the Cullen report. It will take a lot more time to read completely.
I am impressed with the quality of the report.
The Cullen report was definitely not the report that I was given.
I may have been given only one chapter of the Cullen report, in which case the disclaimer may have applied to that chapter only.
I haven't found it yet.

And in regards to helicopters there was the crash of Cougar Helicopters Flight 91.
The pilots were not aware that the aircraft gearbox did not meet the 30 minute "run dry" standard. They assumed that they had time for a return to St John's International Airport. The gearbox failed 8 minutes later.
In 2003 the S-92A initially failed a FAR/JAR-29 additional oil system loss of lubrication test (sometimes called the "run dry" test) conducted to determine whether it could sustain 30-minute operation without main gearbox lubrication, failing after 10 minutes.[27] Subsequent design changes implemented an oil cooler bypass valve to eliminate what were seen to be the most likely sources of leakage, the cooler and external lines and fittings. Certification was obtained without meeting the 30-minute test as the chances of oil loss were calculated as being "extremely remote",[28] a statistical chance of failure of approximately one in every 10 million flight hours. This was based on the erroneous assumption that all leaks would occur from the oil cooler, and so did not represent the type of leak that occurred to Flight 91 or to a CHC S-92A in Australia the previous year.[29][30]
Link

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Alistair_Heaton]

Don't worries mate. NO apologises required.

I am up to 14 pilots now that I have known that are now dead due various accidents. The commercial side of things that I do now is very safe we often say the drive to the airport is the most dangerous bit of the day. The pre multicrew days were not anywhere near as safe. All of the fixed wing where killed burning petrol not Jet A. All experienced and knew what they were doing but a combination of events (including them screwing up sometimes by not pressing a single button) meant that they aren't with us any more.

I was 16 at the time of Piper and to be honest in the 70/80's in Aberdeen it wasn't that uncommon for kids to get pulled out of class because their dads had been killed or had life changing injury's. In fact the year before that I had started labouring in oil yards and while slinging pipe one of the wire strops broke and dumping the string. The guy I was working with tried to run away from the lorry and I went under the axles. I am here now to tell you about it he isn't. Very changed times, the last time I was in an Aberdeen oil yard in 2006 where if you walked up a set of stairs without using the hand rail you got a written warning. And if that was combined with coming out the toilet not wearing your high viz, safety glass and hard hat you were out of a job. If it was a singular memory of that type of event then it would be a painful trigger but unfortunately its not.

And its worth finding the Ladbroke Grove rail crash report which Cullen chaired as well. He also did the Lockerbie report.

Being an Aberdeen lad the trials and tribulations of the mechanical palm tree's I must admit I do follow.....from a distance. I would never get in one or allow a family member into a helicopter, intrinsically dangerous devices 6 out of the 14 pilots I have known killed have been due to them and I know probably in the region of 40-50 fixed wing pilots for every rotary pilot.

To be honest something breaking and killing them is easier to deal with than knowing that they screwed up (which unfortunately is most of the time). The closed coffins and dealing with their relatives is also a big issue. We know as pilots that if you hit the ground at 200 knts plus the harness just acts as cheese wire and cuts your body up. Closely followed by the instrument panel acting as a garlic crusher to puree the rest when mill seconds later you hit it.

So the most traumatic part of the proceedings is listening to someone's mum complain about the undertaker who is apparently heartless not letting her see her boy/girl for the last time. We all know that what they have managed to recover will have been put into the coffin from a bucket, double bagged if there was a fire and the weight made up with gelatine bags. But you can't tell her that... You just make a point of having a quiet word with the undertaker saying as a pilot you know the reasons and thankyou for looking after our mate.

 

[Alistair_Heaton]

oh and I must admit I am not a great fan of locking out controls either. You either have them to be used or you design in interlocks to prevent the use in certain situations.

In aviation we use guarded switches which are also colour coded. So all the important ones which are irreversible require you to lift then press. The control handles are also textured and shape coded as well. So the gear handle is shaped like a wheel. The prop condition levers have a wave a effect on them and on complex petrol aircraft the mixture levers are a square block. The J41 the condition levers also had red lights in them which lit up with the fire alarm so you didn't grab the wrong one to shut the engine down which actually worked extremely well.

 

[waross]

When I am talking about locking out equipment it is because the equipment is down for some reason. It may be partially disassembled, some-one may be working on it or for some other reason it should not be used.
I had an idiot who visited me and who I told that I was working on a circuit and to not turn it on, then go directly to the switch and turn on the circuit. (I left. Don't know and don't care who finished that job.)
I have had a supervisor tear off my "Do Not Operate" tag and that of my partner and close the switch.
I saw a supervisor who looked at a machine and was told that the machine was not yet ready to run and that a worker was adjusting the gears, then go and start the machine.
In the Piper Alpha disaster, apparently managers started a pump that was missing the safety valve. (PSV)
They either misunderstood or ignored the paper work.
Had there been a lock used, they would have found the off duty worker who had the key and been told why the pump was out of service.
I understand from the Cullen report that the rig was having serious problems but starting the pump did not help and may have been the trigger to the disaster.
I have seen too many managers put their personal convenience ahead of safety. You cannot bypass apadlock quite as easily as you can bypass a piece of paper.
I like locks.
This brings back memories:
"The guy I was working with tried to run away from the lorry and I went under the axles."
I was unloading a logging truck and the load had shifted badly. I could see the logs starting to move as I released the last restraint. I dove under the truck and was crawling under the trailer axle as logs cascaded down both sides of the truck.
I had a two step rule in those days:
1 Where will the danger area be when something breaks.
2. Don't be there.


Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Sparweb]

Update:
The FAA is accepting for now the assertions from Boeing that the system modifications can reduce the hazards. It also seems that the largest pilot's unions in the USA are on board with proposed (non-simulator) training changes. The scope of the training changes seems to be growing beyond the 737-Max but to include all 737's. This is expressed as an oversight, or inadequacy in the procedure on all of the models that can be corrected at the same time as this one. Training on simulators is not being pursued. Training the flight crew responses to AoA sensor equipment failures does not seem to have been discussed.

https://www.bloomberg.com/news/arti...no-need-for-new-simulator-training-on-737-max

For their part, pilots from American Airlines say they have tested the proposed fixes from Boeing in simulators, but AA does not plan to offer simulator training to all pilots flying the 737 Max. Depending on the articles I read, it seems that the community of airline pilots are not fully behind the union's position that simulator training is not required.

I am relieved to see that Canada has the right person in the lead of this case:

Transport Minister Marc Garneau said on Wednesday that the planes would be grounded “for as long as it takes” and pilots should experience the fixes Boeing is devising in simulators instead of relying only on more basic, computer-based ground training.

The stance of Transport Canada, if it's maintained after the US reintroduction of the 737-Max without sim time, could become a painful competitiveness issue between our countries' airlines. I personally support Garneau's position. The "modern" analytical method has failed, so the "old" simulator method of training should be adopted. It will be far more effective at restoring public trust than another analysis. It may also assert some reality check on the assumptions in the safety analysis, which, who knows, may still be flawed. If the regulator imposes simulator training on the air carriers, which presumably would include response to system failure, then the back-and-forth decision about training costs gets taken away from airlines.

I am curious to see the results of simulator scenarios based on the new MCAS, especially the results from pilots who are subjected to the MCAS behaviour with an AoA sensor (or other type) failure. And I would want to see it done with airline pilot crews, not just Boeing's company test crews. Comparison with the simulator test of an original MCAS failure would give everyone a much better understanding of the level of improvement that can actually be achieved. I do wonder how many crews in the sim will crack up on their first try, before getting the procedure down and steadying the plane out.


No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

 

[saikee119]

One would have thought every 737Max pilot would be interested to see the difference between the old and new MCAS at least in a simulator?

 

[Sparweb]

Sim's are fun and valuable learning tools. And expensive. The pilot's union may be more sensitive to the cost than individual pilots.

Here's a demonstration of what an out-of-trim situation looks like in a 737-800 "Next-Gen" simulator.
They purposefully mis-trim the aircraft for the demonstration, but the result of the situation looks authentic.
The right-hand pilot has a lot of difficulty dragging the trim wheel around, in either direction.
If you watch the whole video, you can get a pretty good explanation of the opposing forces on the stabilizer when mis-trimmed at high speed (probably better than the explanation I attempted a while ago).

No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

 

[Alistair_Heaton]

First thing I thought when I saw the sim stuff was that's Innsbruck horn that they are trying not to crash into.

This is where its going to become political. There is no other options apart from Airbus in the MAX's market. And the Unions will not want to be blamed for the MAX turning into a dodo.

There is only one sim in the world loaded with the MCAS flight model... And its Boeings in Seattle. And the purchase of the sim model costs millions per sim. Which is why they more than likely want to link the fix to the 737-800 as well.

I haven't seen anything from EASA yet and Ryanair isn't saying anything in regards to the training side of things.

The certifcation issues need to be sorted first completely before the training can be looked at. I still suspect that the FAA will recertify the MAX but the rest of the world won't in the short term. So it will be flying again internally in the USA. Quiet how the public will react to that I really don't know. Most won't have a clue what type of aircraft they are boarding until they see the emergency brief sheet.

The way they pay pilots in the USA is different to most other areas. We get paid a salary for a certain number of hours and overtime above that number. If we fly less than the contract hours we still get paid the same. In the US they get paid by the airborne hour. If you don't fly you don't get paid a dime. Also we get paid for time in the simulators and training etc. US pilots don't, it doesn't even get counted towards rest time for flight time limitations. You do your training in your own time, unpaid, and if you fly for 6 days then are in the sim for a day then fly for another 7 days thats all legal because the day in the sim is counted as a day off. So I am not really suprised the pilot unions don't want thier members to loose money having to go to the sim. A conversion course would be a couple of days in the class room and 2-3 4 hour sessions in the sim so 7 days with no salary.

I might add that the above is a general statement there are some companys who have a more progressive and safety minded culture and do things differently. Fedex is an example that bucks the norm.

I don't have a clue how they do it in Canada.

Edited to add this articel

https://www.nytimes.com/2019/04/20/business/boeing-dreamliner-production-problems.html

 

[moon161]

Pilots being unpaid to learn to fly safely has to be one of the most scary things that I've just learned about. That and low junior pilot pay and sick rules, that makes me think of flight 3407 (one of the pilots was sleep deprived and sick because she couldn't afford to be sick) which crashed on the opposite of the airport approach that I live under.

 

[waross]

I just had a chilling thought.
It is acknowledged that the engines will provide not just added lift but also a trim up effect at high angles of attack.
Is the converse true?
Will the engines provide an added trim down effect when a bird takes off an AoA sensor and MCAS does the "dive of death"?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Alistair_Heaton]

no they won't, its basically a newton effect of flat face in an airstream, the angle gives it a force vector. if the nose is pitched down the face that the vector is on is internal to the engine and will have its airflow changing the vector.

The trim up effect is due to the point of pressure from the engine vector being forward of the Centre of gravity. There will be the same effect on other engines configurations but because they are not as far forward the moment will be less. Also they have a more rounded shape so the vector is smaller.


There is a huge what we call pitch power couple anyway due to the centre of thrust from the engines being below the CoG. This is considered normal for every under wing jet and pilots just have to deal with it and its acceptable for certification although some makes and models now automatically trim for it. Which I suspect is half the reason why MCAS was needed. I don't see it really for takeoff. Its a go around its for when your set up on approach and then you hit TOGA and the power goes from 30-40% N1 to 100% and you will be manual flying. Flaps cause a nose up pitch when they are retracted.

So you have multiple additions to pitch the nose up anyway. Just that the force to increase Alpha with all these effects increases the nearer you get to the critical angle alpha they stay constant. Problem with the leap engine configuration is the force vector increases the moment with alpha so the control forces decrease.

 

[Alistair_Heaton]

Oh and although they seem to have missed it completely in the Colgan accident report and just say they didn't follow stall recovery...

They did actually follow a form of stall recovery. That of the elevator stalling which normally happens just as you select the next stage of flap. And the procedure is pull back on the stick and remove flap... Thing is we don't have a warning system for elevator stalling. It just happens due to ice build up on the tail. You pull back on the stick and remove flap get her flying again and then find a runway long enough that you don't need flap to land on. But its not normal for pilots these days to be taught about it. The only reason why I know about it is because of that week flying with Tim the auld test pilot.

The real problem was that the US used to have a test criterial of only loosing 100ft during a stall which the rest of the none FAA world didn't have and actively taught the opposite. So FAA pilots would always try and power out of the stall which works okish when its just the stick shaker because that's warning you your approaching but your not actually stalled yet. When your stalled the only thing that will allow you to recover is to reduce the angle of attack. They have since changed things but there are a lot of old instructors and examiners still teach the old method.

 

[charliealphabravo]

I always thought the Me-262 must have had a serious nose-up tendency due to the position of the engines.

Edit: At the risk of going TOO far afield I post this stunt as a classic example of center of thrust below center of mass: