Boeing 737 Max8 Aircraft Crashes and Investigations [Part 7] 16

[Sparweb]

This post is the continuation from this series of previous threads:

thread815-445840
thread815-450258
thread815-452000
thread815-454283
thread815-457125
thread815-461989

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 (Link is now broken. See PDF download below, 3 MB)

Indonesian National Transportation Safety Committee preliminary report

A Boeing 737 Technical Site

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

BBC: Boeing to temporarily halt 737 Max production in January

www.sparweb.ca

 

[Alistair_Heaton]

They are also talking about putting drive wheels on the nose gear so the engines are not running going out to the runway. I can't see it happening due to weight penalties either.

Aye BHX is a bit of swine if you don't touch down ontop of that first bump. You have to increase the rate of decent due to ground falling away. Then it comes back up and hits you. They have built up stuff round the airport and wind coming from certain directions turns the approach into a bit of a washing machine in the last 500ft.

You can't see it in the photo but they have lots of rubber in the touch down zone, it is a grooved runway and when its been cleaned of rubber which I think they do by burning it off its pretty good. Just before cleaning though its very slippery when even damp.

 

[Alistair_Heaton]

Anyway back to the MAX whistle blowers and FAA. It does seem to be playing out as per Challenger.

Some articles from the award winning Seattle Times.

https://www.seattletimes.com/busine...lower-alleges-systemic-problems-with-737-max/

https://www.seattletimes.com/busine...x-cast-doubt-on-agencys-role-ensuring-safety/

 

[Alistair_Heaton]

Up date on progress and which systems the regulators are having issues with.

https://www.seattletimes.com/busine...ew-changes-to-boeing-737-max-flight-controls/

All has seemed to have go quiet about wiring looms and control run routings.

I don't known though if there is any demand for new aircraft or for that matter if the public will be happy to fly on them until everything is fixed. Take delivery of an airframe which you know will require major mods in the near future and nobody is flying anyway so demand is extremely low.

 

[JohnRBaker]

It appears that Boeing and the FAA will start conducting a series of test flights of the 737-MAX8 aircraft as early as this Monday. This will involve an aircraft, loaded with instruments, which will conduct various simulated scenarios testing the systems and subsystem which the experts believe were responsible for the crashes that grounded the 737-MAX more than a year ago:

Boeing set for critical 737 Max flight tests

https://www.bbc.com/news/business-53212274

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Alistair_Heaton]

You can usually follow them on most flight trackers.

They fly under BOE

So on Monday have a look for BOE1. They usually take off about 12:00 GMT

 

[1503-44]

Let's hope that "Software Defined Aircraft" don't have 'systems crashes".

“What I told you was true ... from a certain point of view.” - Obi-Wan Kenobi, "Return of the Jedi"

 

[Alistair_Heaton]

Seems they are using BOE701

They do sometimes have system crashes. But the backup systems spots it and removes the offending computer from having any input to the flight. The aircraft then down grades things then takes the offending computer down. Brings it back up and then you have everything back to normal again. If it then fails x number of times in a row it then it throws other cautions up which then you can then sort by say taking a sensor out of the equation and reverting. Then everything works again. Well that's the way it works on a proper FBW machine. Quite what this 1960's Frankenstein contraption will do I really don't know.

 

[3DDave]

That Frankenstein contraption is better put together than the CAAs of at least 3 countries we know of.

 

[Lou Scannon]

System Engineering, if performed competently, should feature robustness and resilience in the event of single point failures, and should at all times make maximum use of remaining reliable components to minimize the effect of one or more component failures.
That may be a big if.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[IRstuff]

It's a tough row to hoe from systems engineering principles to actual practice. But, SE, per se, is usually not the onlt problem, it's also a number of other problems
> shiny new SEs that know SE principles, but not how or why a system exists
> requirements creep because the requirements have to be iterated multiple times because of "I forgots"
> poor management because the managers don't know what's going on
> ballooning costs
> poor systems engineering on the legacy portion of the system


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

 

[Alistair_Heaton]

I would say there is a lot more CAA's than that Dave. And to be honest its the regulation that just as much at fault here than anything else.

I must admit I am just about finished learning a new fresh sheet type. Don't get me wrong there is a bug list as long as your arm even though its been in there air for 3 years now. And there is a well defined method of submitting bugs and regular updates to clear them. But compared to the Q400 which was a 4 generation upgrade stretch its absolutely heaven. There is crap on that beast that will never be fixed because its just the way the system has to be because of the changes. All the issues which I am seeing are all icing on the cake getting things working which were planned to be working. So its all stuff which is envisaged should work 99.99999% of the time but it only working 99.9 of the time and they are fixing it. But in no case is there major changes to the way we operate the machine.

The avionic regression failure is truly impressive on the A220, there is checklists and failure modes which take you back to some weird and wonderful setups. But you have to get multiple events usually involving electrics as well before you can't cure it by changing a sensor input to something else. And once you do then you get everything back but with riders that the system can't protect you anymore.

I was in at 4am last night doing volcanic ash and fire and smoke both of which involve pretty horrible checklists and failures. Compared to other types it was a breeze to deal with mainly because the checklists where ordered correctly and systems where dealt with in the required order. Instead of the pair of us having to make critical choices after having 20 hours awake after working 5 days in a row.

Anyway 2 days off now so I am away to find a beer garden today, will hit the books again tomorrow for the joys of autolands and 50 meters viz which is a new one for me.

Actually come to think of it last night with volcanic ash event which occurred over Norway we lost all 6 AoA sensors and all the airspeed indications one engine after having a dual flame out and being able to relight one of them, and the windscreen was screwed so all we could see out of it was a blur at 200ft not helped by having the masks on. We managed to get it down using 65% thrust on the live and -3,5 nose down, wasn't pretty but we stayed on the runway. It was basically keep it aligned when we hit 30ft take the power off pitch to 7deg nose up and wait for the bang and keep the thing in the middle of the runway with the rudder using the loc beam while braking like hell. Put the handbrake on and evacuate.

 

[waross]

I hope that that was in the simulator.

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

 

[Lou Scannon]

Hey Alistair, I'm keeping up with most of your jargon, but care to edit the above for typos? I couldn't quite make sense of the last bit:

Already had words with man about they are on there tod outside keeping the aircraft safe

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[3DDave]

https://www.youtube.com/watch?v=CYvFxs32zvQ

 

[Alistair_Heaton]

Sorry had a rare day off and on phone. I deleted it because even i couldn't understand it.

The sim is running 24h with 1 hr a day down time for a reboot and maint.

The cockpit dynamics in a lot of company's after lay off's has changed with experience increasing but the gradient of experience possibly changing due to seniority lists

It gives the possibility that the person in the FO's seat has significantly more experience than the person in charge of the aircraft which gives plenty of scope for conflict.

Yes the above situation was in the simulator. The western aviation industry does not as a rule train people in the aircraft. All these scenarios are dealt with over a 3 year period with 2 4hr sim sessions every 6 months. On initial rating you cover all of them while learning the various systems and the relevant failures and checklists and methods of dealing with them for the particular type. As history dictates with real life situations and accident/event reports they add in different scenarios. The current big one in Europe is stalling in landing configuration and wind shear. I don't think its a specific event that triggered it just that the safety folk in the regulators are seeing a trend that crews need this area revisited or reinforced. In the past things have concentrated on avoidance not actually dealing with it now we are doing both.

The volcanic ash is a good multi failure exercise which gives powerplant, electrical, instrumentation and limited visibility issues and if they think your up for it they can throw cabin fire in on top. Its pretty full on for 30-40 mins. Quiet a few company's use it to asses if the person is ready for upgrade to Captain.
My sim partner is also another experienced Captain so we got the full works thrown at us. If the crew was two 200 hour first officers on their first type rating they will limit the failures so its manageable for there experience level. ie they will cover the same individual scenarios just not all at the same time.

 

[Lou Scannon]

Sorry had a rare day off and on phone. I deleted it because even i couldn't understand it.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

 

[waross]

US Regulators Complete Test Flights On Boeing 737 MAX
While the flight tests in Seattle are "an important milestone ... a number of key tasks remain, including evaluating the data gathered during these flights," the Federal Aviation Administration said Wednesday.

Link

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

 

[Alistair_Heaton]

Just an update with the training requirements that are current just now.

https://www.flightglobal.com/airfra...ings-latest-max-training-draft/139253.article

Don't have a clue what will be required in the USA.

In Europe its looking like a new type plus differences training as is now the case between classic and NG 737 models.

This is god news in the grand scale of things because at least they have a target to meet and they are providing probably more than they have to.

Bad news is that pretty much globally every one doesn't want new aircraft especially with the current oil price.

So some pretty major orders are entering the courts to be cancelled. I only know the European side of things. But the major order number of normal types has entered court to get the money back from deposits and the other major order the aircraft has never been certified yet.

I wouldn't be surprised if under 2500 airframes are ever built. And out of that over 50% of them will be taken with complete reluctance.

BTW airbus are completely screwed as well with its order book just none of its customers have an excuse to cancel.

 

[3DDave]

Maybe this time pilots will be taught what Memory Items means and how to use the trim button on the wheel. For certain they did not get that the first time.

 

[Alistair_Heaton]

I presume they will, but as its so far completely away from a normal aircraft it will remain a special. I certainly won't be effected by the training requirements

It will have its own set of required scenarios which will more than likely go over into 3 days every 6 months which will kill it. Not that its not already dead anyway.

Utterly pointless me training for most of this stuff I can trim from high speed end to low speed end don't have a physical limitation and neither do the 60kg females I fly with what ever speed we do. The electrical trimmer never gets killed from my direct inputs. Well it does but its 3 or 7 levels down depending if you want to count all three PMCC computers going tits up as one failure if one goes, or each one a failure. Which is way way outside 1 in stupid amounts of millions flight hours. And even then we have three backup systems and the 737 has a sum total of cock all.

737 max one computer going tits up and your on your own.

Your choice as punters I won't be flying them then thankfully. I suspect it will be extremely doubtful I will every strap my bum in the back of them either. I have a choice I suspect most of you won't.

Its got one chance now otherwise its dead. It won't be my life online I will tell you for that much. You Yanks can be the test pigs.

II can't see any Boeing successes with software in the last 10 years be it civil, mil or space. I am pretty confident we won't see a success now. But I would utterly love to be wrong because only having one hardware provider is not good for man nor beast.

BTW the only memory item I have is put my O2 mask on in the event of explosive decompression. Just one the 737 pilots have double figures worth of memory items each of which is 7-12 items long. As a pax in the cabin, why the hell would you ever trust your life to one if I won't as a pro pilot.