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Boeing 737 Max8 Aircraft Crashes and Investigations [Part 5] 19

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Sparweb

Sparweb

Aerospace
May 21, 2003
5,131
This is the continuation from:

thread815-445840
thread815-450258
thread815-452000
thread815-454283

This topic is broken into multiple threads due to the length to be scrolled, and images to load, creating long load times for some users and devices. If you are NEW to this discussion, please read the above threads prior to posting, to avoid rehashing old discussions.

Thank you everyone for your interest! I have learned a lot from the discussion, too.

Some key references:
Ethiopian CAA preliminary report

Indonesian National Transportation Safety Committee preliminary report

A Boeing 737 Technical Site

Washington Post: When Will Boeing 737 Max Fly Again and More Questions

No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF
 
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The only connection I have with airplanes is as a passenger, but I live outside of Tulsa under a flight pattern for TUL and all the remaining American 737 MAX are being ferried here from storage at Roswell as Tulsa has the largest maintenance facility. I thought you might like to see the two most recent flight patterns (both in early Oct) if you hadn't seen them before, according to Flightaware.
Link
Link
 
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Thank you RVA,
That article about the e-mails puts a dark tone on the development process.
Forkner and Gustavson discuss the MCAS problems as if they did not think they were accountable for the problem. In the end, they may be held to account more scrupulously than they expected. Especially if they're called back to testify to congress (again).

How many of us engineers have had a similar exchange by text message or e-mail like this? The actual exchange is reproduced in the PDF below (from Reuters):

www.sparweb.ca
 
 https://files.engineering.com/getfile.aspx?folder=3c57963e-b998-4da1-966c-3a4731abf49c&file=Boeing_Document_Forkner_Gustavson.pdf
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Mind you this is only the witch hunt. I will admit I have zero clue about the process in the US. The little I do know is from reading about the shuttle disaster and reading the Truth, lies and o rings by Allan Macdonald.

And unfortunately there seems to be quite a few similarities in the time line and management input into the engineering.


A lot of us in the industry are more concerned about how and when they are going to get this Frankenstein ship flying again. They still don't seem to have grabbed the bull by the horns and admitted that they screwed up big time in not just the MCAS area.
 
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Its just a statement saying when the earliest time it could be flying is.

They have test flights scheduled for December. If they don't have any issues at all in those flights the earliest they could see the fixes being certified is mid Jan.

Once the airframe is certified again then they can talk about the manuals and training side of things.

But EASA is famous for these announcements on time scales. They have to say something because some regulation or politician requires a statement. So they make one which means absolutely nothing and ties them down to not a thing.

What I suspect is happening is that Ryanair is putting pressure on the Irish side of things because they are well and truly screwed just now. Aircraft leaving and nothing getting delivered, crew getting released on unpaid leave bases closing. And this is then getting fed through to EASA. I don't know for sure though, its extremely tight on gossip for the whole thing now.
 
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Bloody certificates. It’s all anyone cares about.
 
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All I am hearing is ignore everything you see released by all parties on timings until after the crash reports and the test flights. There is some required statements due to the financials coming up and everything is geared around a strategy of dealing with that and stock price.

And the financial stuff and pandering to share price is the whole reason why they are in this mess in the first place.

There seems to be a race on between the financial stuff release and the release of the first crash report which is due by the end of November.

The circle of the legal process in the USA surrounding various investigations by multiple groups of people and what the end result of those investigations I will admit is a huge mystery to be honest to those of us in EASA land. Will it be the small individuals that are used as collateral damage or will they go for the people who were actually driving the process. Or as I suspect it will result in absolutely nothing.

The relatives of the lionair crash are being briefed on the final report and it might be released on the 29th of October.

Its looking likely that the FAA flown test flights won't happen in Nov. If they don't happen the EASA ones won't happen in December. If the conclusion is that MCAS is an anti stall device then your looking at easily another 6 months more likely a year. If the handling without it is deemed none compliant then they are going to have to certify the whole Flight control system to a higher DAB level and build in another failure layer before the pilots have to manually fly it. I have zero clue how long that would take.

If they don't have movement in Nov its likely they will have to shut down production which has huge ramifications for after they do get it flying again.
 
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they haven't put the full report up yet on the AIBB site.



To note its 6 out of 25 recommendations that are pointed towards Boeing.

The maint records were as expected utter garbage with 30 days worth of records missing.

A valid complaint of pilots not writing up a snag with complete information for the techs to work with. Please note this is a world wide issue with pilots recording utter bollocks in the tech log and then disappearing off leaving the techs to try and find out whats wrong. In most aircraft these days the ecam and fadec systems record the last 50 hours of flight and they can play it back and see everything that happened. The MAX doesn't have a ECAM system because that would have blown grandfather certification out the window and required sim training.

And a Florida based overhaul facility apparently sent an uncalibrated AoA which was then fitted to the aircraft and the tech didn't check the calibration after fitting as per the Boeing maint manual.

So as usual a series of holes in the cheese, some human factors both pilot and maint, dodgy part involvement, and the issues we all know about with the original design.
 
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Final report is out for lion air online.




To note the dodgy repair shop in Florida who was the first slice in the cheese closed yesterday the moment the report came out. It did this itself and wasn't closed by the FAA.

Update on the part refurbishment shop, It did a deal with the FAA to shut without further action by either party. But per say it was compliant with its approvals. It's just that the approvals were granted by the FAA without it being compliant without the relavent requirements by the FAA.


Seems a bit strange to wait 10 months and only do it on the day of the report coming out.
 
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From the accident investigation report:

Substantial shortcomings in the crew's response to the situation.
[ul]
[li]Emergency was not declared[/li]
[li]Checklists not followed (not even consulted)[/li]
[li]Communication breakdown between pilot and first officer[/li]
[li]Incomplete pre-flight briefing[/li]
[/ul]

Maintenance problems:
[ul]
[li]The maintenance engineer released the aircraft for flight with incomplete maintenance[/li]
[li]The AOA sensor that was installed was malfunctioning.[/li]
[li]The maintenance engineer that installed it did not properly verify its function.[/li]
[li]"the aircraft was released with known possible recurring problem."[/li]
[li] maintenance not performed to diagnose possible related problems [/li]
[li] "the engineers were prone to entering the problem symptom ... instead of reviewing the OMF maintenance message"[/li]
[/ul]

It also implies:
[ul][li]deliberate falsification of maintenance records[/li][/ul]
(More on that below)


Shortcomings of Boeing's design are already known and reviewed by the investigation:
[ul]
[li]Non-linear flight control forces at high angles of attack / high g load conditions[/li]
[li]No angle of attack instrument display in cockpit[/li]
[li]No AOA Disagree indication in cockpit displays (unlike previous 737's)[/li]
[li]New automatic trim-adjustment system[/li]
[li]No training available to inform any crews of the above differences[/li]
[li]Emergency procedure for AOA Disagree inadequate to resolve this accident condition[/li]
[li]No Abnormal procedure for MCAS malfunction[/li]
[li]Repetitive erroneous activation of MCAS was not considered in the system Functional Hazard Analysis[/li]
[li]Full operational envelope of MCAS was not considered in the system Functional Hazard Analysis[/li]
[li]Full operational envelope of MCAS was not tested by simulator or flight crews[/li]
[li]Many more, but that's enough for now...[/li]
[/ul]

Investigators also encountered this:
"The engineer in Denpasar provided to the investigation some photos of the SMYD
unit during an installation test as evidence of a satisfactory installation test result.
The investigation confirmed that the SMYD photos were not of accident aircraft
and considered that the photos were not valid evidence."​

and this:

"The BAT LMPM required the engineer to record the test values to ensure
that the test results were within tolerance. The engineer did not record the value of
the AOA angle deflection during the AOA sensor installation test."
​

My interpretation of the findings on page 185-188 (though not the investigators' statement) is that the maintenance person did not perform the required test, and filled out a release for flight without either testing the equipment that had been replaced or even finding out if it was functional. That person later provided the investigators with false evidence of doing the test in an attempt to back up the false claim.



 
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Yep.

But also the refurbishment company using none OEM approved calibration equipment which the FAA had approved with no written procedure.

Also reading between the lines the fo was what we call a career fo. And also significantly older than the captain. It doesn't make for good cockpit dynamics.
 
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Update on the part refurbishment shop, It did a deal with the FAA to shut without further action by either party.
Click to expand...
But also the refurbishment company using none OEM approved calibration equipment which the FAA had approved with no written procedure.
Click to expand...
The FAA order was part a settlement agreement with the company in which it agreed to waive its right to appeal the revocation to the National Transportation Safety Board or any court.
Click to expand...
Reading between the lines on this: It looks as if the FAA doesn't want anyone looking too closely at their shortcomings in this part of the Cover Your ASSets game.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
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After finishing reading it.

It's pretty normal accident report in relation to maint and crew standards from a developing area of the world.

If you look at other reports on the Indonesian accident investigation board you will see a common theme. I expect the Ethiopian report to have similar issues. But with it my gut feeling is that it was a bird strike, so the maint side will not play as big part.

What this report has highlighted is that it's not just the aircraft certification branch of the FAA which has issues. If the common approvals of FAA maint facilities is also thrown out the window it sets the common standards and approval world back 20 odd years and vastly increases costs for everyone.
 
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