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rob Lyttle

737 Max

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19 minutes ago, stever219 said:

The Airbus jets haven’t been subjected to airframe/power plant/systems changes that have significantly altered the aircraft handling characteristics in certain critical flight regimes that have then required a deliberately-concealed piece of software/hardware which can be disabled by a single failure to correct them.

That's right. The degradation of control laws (a concealed piece of software that significantly alters handling characteristics possibly from a single failure) was built in from the beginning and is not accessible by the pilots, which is why Airbus aircraft feature disproportionately in upset and LOC-I incidents, and still do. Software 'upgrades' and additional training has been and still is necessary with each new or repeated incident.

 

The Airbus philosophy has been to make the handling of each member of the family as near to that of the others that, whichever jet they are flying, crews can respond instinctively to any given upset without having to go through several pages of the QRH or FCOM to find a nearly-concealed check list.

 

The whole point is that pilots CAN'T react instinctively to Airbus flight instrumentation degradation without specific training as the cues are all given through the visual channel - there is no analogue feedback through control forces or positions. It requires specific and ongoing training for pilots to recognise and handle degradation and instrument disagreement, which can be caused by a single failure, like an ADC or sensor.

 

Control and instrumentation failures are not Airbus-specific issues, but pretending that Airbus aircraft have all these things ironed out is denying reality.

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BBC reporting further issues with the 737 Max production.   FO in the fuel tanks found in stored aircraft.

 

I dont know how much of an issue that really is  - not enough knowledge on my part - or if its just newspaper alarmism in the sense that these things can happen and are routinely dealt with - or is it something that should never happen in production.  I'd bet on the latter but have a scepticism on journalism these days.  No doubt wiser and more knowledgeable heads than mine will advise

 

https://www.bbc.co.uk/news/business-51499777

 

 

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To quote form the article:

 

"The head of Boeing's 737 programme has told employees that the discovery was "absolutely unacceptable"."

 

If the head of the 737 programme feels the need to address this in these terms, it's an issue. 

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5 hours ago, JohnT said:

BBC reporting further issues with the 737 Max production.   FO in the fuel tanks found in stored aircraft.

 

I dont know how much of an issue that really is  - not enough knowledge on my part - or if its just newspaper alarmism in the sense that these things can happen and are routinely dealt with - or is it something that should never happen in production.  I'd bet on the latter but have a scepticism on journalism these days.  No doubt wiser and more knowledgeable heads than mine will advise

 

https://www.bbc.co.uk/news/business-51499777

 

 

Same issue was found last year on KC-46 leading to the USAF stopping accepting them.

 

https://www.airforcetimes.com/news/your-air-force/2019/04/02/air-force-again-halts-kc-46-deliveries-after-more-debris-found/

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5 hours ago, NoSG0 said:

It’s not so much where the wiring comes from but how it is routed and bundled within the aircraft.  In the 737MAX there is a bundle containing a “hot” wire routed close to two “cold” wires which are part of the tailplane trim system.  The concern is that chafing within the bundle could lead to arcing from the “hot” wire to either or both of the “cold” tailplane trim wires which could produce rapidly alternating nose up and nose down signals to the tailplane motor which the pilots might not be able to override.

 

Some of the Boeing hierarchy deem this to be a low-probability event but an RAF Puma, IIRC, was lost as a result of very similar damage to part of its wiring loom leading to the power supply for a flashing anti-collision light feeding spurious alternating pitch demands to the main rotor cyclic controls.  Eventually the uncommanded control inputs caused one of the main rotor blades in the rear arc of their travel to lower sufficiently to strike the tail boom and disrupt the tail rotor drive shaft.  All too often aviation has demonstrated the ability of lightning to strike in the same way more than once...

 

It remains to be seen whether the FAA will compel Boeing to do something about this or not.  Apparently very similar wiring has been used on the 737NG with no reported failures, yet, and Boeing will probably rely on that to get a laissez-faire decision from the FAA.  Boeing has so far failed to heed the FAA’s ruling that the rudder cables on 737s should be separated in order to increase survivability in the event of structural damage as it hasn’t resulted in an accident yet/recently.  

 

The conspiracy theorists can have a field day with how much influence Boeing has on and over the denizens of Capitol Hill and the White House (Trump, after all, has a blinged-out 757) and thereby the FAA, even though the USAF has possibly fallen out of love with the company over the delays, cost overruns and quality control issues in the KC-46A programme.  EASA, and other airworthiness authorities, may not follow the FAA’s lead even if the latter does recertificate the 737 MAX 8 and even though Trump is already instigating a trade war with Europe which includes duties on civil aircraft.  A retaliatory duty charge by Europe can only do further damage to Boeing which the company presently can ill afford.  

 

Apparently KLM is considering abandoning its plans for an all-Boeing fleet and is sizing up the A321 as a potential 737/737 MAX successor but Airbus could be very hard pushed to increase production rates even allowing for them having four assembly sites, one of which is in America, for the A318/319/320/321 family whilst maintaining quality.  It’s probable that any entirely new site would take four to five years to come on stream, by which time Boeing might just have got the MAX 8 can of worms back into its bag of nails.

Edited by stever219

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On 2/20/2020 at 1:52 AM, NoSG0 said:

Let us all hope that if the FAA does not force a fix that nothing serious happens.

That's their dilemma; if they force a fix it will cost Boeing and their MAX customers dear which will lead to higher fares for the travelling public at the very least.  If they don't force a fix and people are hurt or killed as a result the ambulance-chasers' feeding frenzy will have to be seen to be disbelieved and there will be higher fares for the travelling public.  Also the FAA's credibility as a regulatory authority will be seriously compromised.  Damned if they do  damned if they don't....

Edited by stever219
Sppelinn

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At this point, the FAA's credibility as a regulatory authority has already been seriously compromised - the relationship with Boeing has been exposed as being far too cozy, and their failure to take serious action on airline maintenance and safety issues is appalling. This country has been forced into a Wild West situation where the federal government and its agencies are forced to abdicate their authority and credibility to the interests of cold hard cash. 

Edited by Paul Bradley

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21 hours ago, NoSG0 said:

Dilemma over 737 wiring.  Where does Airbus get it's wiring from?

Airbus at Broughton in North Wales 

 

Trevor

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18 hours ago, Paul Bradley said:

This country has been forced into a Wild West situation where the federal government and its agencies are forced to abdicate their authority and credibility to the interests of cold hard cash. 

Sounds a lot like the basis of Neo Liberal Economics, where making a buck  (trumps  *) overules ethics, humanity, safety, & morals. The 737Max thing couldn't or shouldn't have happened without it. :(

Steve.

* probably an apt choice non-the less.

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On 2/20/2020 at 12:34 PM, Paul Bradley said:

At this point, the FAA's credibility as a regulatory authority has already been seriously compromised - the relationship with Boeing has been exposed as being far too cozy, and their failure to take serious action on airline maintenance and safety issues is appalling. This country has been forced into a Wild West situation where the federal government and its agencies are forced to abdicate their authority and credibility to the interests of cold hard cash. 

I was trying to be polite and diplomatic😉🙄, which is unusual for me.  I’ve often thought that the relationship between Boeing and the FAA was a bit too cosy for comfort.

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More...

 

https://www.google.co.uk/amp/s/fortune.com/2020/02/21/boeing-737-max-warning-light-new-faa-fines/amp/

 

and more....

 

https://www.google.co.uk/amp/s/www.bloomberg.com/amp/news/articles/2020-02-22/boeing-suspends-co-workers-of-pilot-at-center-of-max-scrutiny

 

Boeing must really have no more hair to collectively tear out at this point. 
 

Will there come a point when Boeing throws its hands up and give up on the Max? I assume it’ll be the bean counters who will have the final say on that point.

 

Trevor

 

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It's the routing of the wiring that's the problem . The wiring used is fire resistant and used all over the aircraft industry.

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Hello Trevor

I agree MAX's fate is going to be decided by the bean counters. However, if somehow the type makes it to the air again it is almost inevitable that this same group will eventually try to push through yet another new version of 737. As Steve said, it is basic neo-liberalism: they got away with it more than once, so why not try it again? Of course, I do hope this reasoning of mine is just a product of my cynicism, which had been amplified by a night-long reading of many variations on Murphy's law. Cheers

Jure

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Of course it will be made to fly again. The bean counters will see to that for sure.

 

If it doesn’t then Boeing will be bankrupt. 387 B737 MAX delivered to airlines and sitting idle. Approx 400 undelivered sitting in the desert somewhere. Another 4000+ orders taken (on which some money will probably have changed hands to at least some degree). Boeing has already provided $19 billion for the 737MAX problems leading to its first financial loss in more than 20 years. If it is scrapped how much more has to be written off / repaid?

 

If Boeing goes bankrupt then the US has a major defence problem. It looks to me like the US Govt already recognises that. Look at the talk of new F-15EX orders the day before Boeing made the announcements of losses. Cynical me says the two are connected. The share price actually rose in the immediate aftermath of those announcements, only to fall again. Put simply Boeing is too big and important to the US economy to be allowed to fail.

 

Also, where else are the airlines going to get these 5000 new clean fuel efficient aircraft in the short term? Airbus? They already have an extensive back order list for A319/320/321 despite having 4 factories churning them out. >6000? In an attempt to increase production, the A380 space is being turned over to A321 production, according to what I read recently.

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YWith so much media attention on the 737 Max 8 issues the maiden flight of the 777X has gone almost unremarked upon.  However it appears that Boeing is trying to certificate this (sub) type using the same “grandfather” rules that allowed the 737 Max 8 certification.  Boeing is basing their approach on the twenty-year-old data submitted for the 777-200.  That might not be too bad, but the X has an entirely different wing built from a completely different material and with folding tips (I believe that at one point these were considered for the -200 but dropped due to reasons of potential lack of public acceptance).  The engines, avionics, systems are different and even the cabin windows are a different size.

 

The FAA is in an unenviable position with this programme, if they allow the certification under “grandfather” rules and there’s an accident involving deaths, injuries and or significant damage to property whoever signs off the certification will be hung out to dry.  On the other hand if they make Boeing jump through the hoops for a new type that will increase the programme costs and put a major US defence contractor and revenue-generator at risk for years to come and whoever dictates that course of action will probably be manning a radar tower in Alaska very early the next morning.

Edited by stever219

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A thread on 777x changes

 

https://www.airliners.net/forum/viewtopic.php?f=3&t=1441751&sid=ec34b7dd74971aee41e4c23da286e263

 

I think all the worldwide Certifying Authorities are likely under a magnifying glass because of the agreements to accept each others approvals.  Should another hull loss occur with questionable decisions made by BA coming out after the fact, then I think that will be the end of these  agreements.  JMHO

 

 

Edited by NoSG0

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