PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Rumours & News (https://www.pprune.org/rumours-news-13/)
-   -   Eight B787 pulled from service over structural issues (https://www.pprune.org/rumours-news/635106-eight-b787-pulled-service-over-structural-issues.html)

Imagegear 18th Dec 2020 07:13

TDRacer,

Thanks for the clarification.

Although the redesign appears to be successful, I am afraid that it will not slip from memory so quickly.

vilas 18th Dec 2020 11:38

turbidus

Dubai cause was different. There the throttles didn't come back to idle but we're always at idle till three second before crash when they were advanced to thrust position and one second before they were out of idle. The autothrottle disablement on touchdown is not due to land mode because sometimes you need to go around even from land mode. The autothrottle is disabled on touchdown or some low RA to prevent inadvertent triggering of GA during Landing.

Dave Therhino 19th Dec 2020 06:04

tdracer - Since the changes were made after the grounding, there have been several main or APU battery fires and overheats that resulted in venting from the containment system in flight or on the ground. The new containment/venting design seems to be working.

tdracer 19th Dec 2020 19:39

Dave, were any of those events complete battery meltdowns, or were they all confined to a single cell? Granted, I'm not as well connected as I was before retirement, but my understanding was that while there were venting events, all the battery failures were confined to a single cell - not the chain reaction complete battery events that prompted the grounding.

WillowRun 6-3 19th Dec 2020 20:59

The Special Conditions for the batteries for type cert.
 
SLF/atty venturing out into this discussion more tentatively than usual....I have just a question. I recall discovering, at the time of the battery fires in early 2013 and which led to the grounding, that the type certification by FAA had involved Special Conditions for the lithium-ion batteries. The incidents were covered in the Wall Street Journal and, for better or worse, rekindled a long-time (long, long time gone) interest I have held, until now pointlessly, in aviation law and policy, particularly in the U.S. and internationally as well. Maybe the articles by Andy Pasztor (and was Jon Ostrower still at the Journal then?, I'm not certain) mentioned the Special Conditions, or someplace else, but I looked them up, and found a topic of interest that appeared maybe capable of ejecting your loyal atty-poster from what was a legal life of drudgery.

The question I have is, knowing what is known now, and realizing that the Boeing engineering and design planning (and market assessment and technology-visionary-encouraging) capacities had weakened even then, would you (a) write different Special Conditions for type certification, using the steel containment box, or (b) try to veto the design component and try sending the airframer back to its drawing board?

I don't know how unusual Special Conditions really are in type certification, or if they are more or less routine depending on what era of aeronautics and aeronautical engineering is being examined, or if it's entirely idle spec to consider these. But then, after the 787, I think the next thing I read about was Asiana in San Francisco in mid-2013, in which article a thing called PPRuNe was mentioned, so....in a sense the Special Conditions were the start of much idle spec overall, SLF/ atty, you know....
WillowRun 6-3

GlobalNav 19th Dec 2020 21:52

14 CFR Pt 21 specifies when Special Conditions may be needed. They are not that unusual especially these days of dynamic technical innovation, when existing standards do not cover requirements needed for safety. The NPRM will state the rationale and identify the characteristics of the design that existing rules don’t address sufficiently.

tdracer 19th Dec 2020 22:40

What Global wrote...

Special Conditions are quite common on new aircraft programs - and the 787 had a bunch due to all the new technology it incorporated (many having to do with the carbon composite construction). New technology can move quite quickly, while new regulations move at a glacial pace (after all, the FAA and EASA are basically just huge bureaucracies). So the FAA uses Special Conditions to address areas where the technology isn't addressed by the existing regulations. Glass cockpits, FADEC, and FBW are just a few areas where Special Conditions have been common. The down side is SC's are a royal PITA to deal with during the cert process.
On the 747-8, I narrowly escaped getting at least two Special Conditions - either by pre-emptively going to the FAA and explaining that we were already going to do what the FAA wanted (uncontrollable high thrust) or by voluntarily stepping up to the newer regulation than what would have been required by the agreed cert basis (HIRF).

WillowRun 6-3 19th Dec 2020 23:54

Okay, I get that SC's are routine or mostly so in context of rapidly advancing technologies and engineering techniques.

What still seems like a question worth addressing (and I'll say "why is it worth..." in a moment) is whether the SC for the batteries turned out so badly that - in hindsight yes, admittedly - some other solution should have been explored. There have been a good number of posters' volleys on various threads about the necessity of engineers to overrule, or try to overrule, the pinhead accountancy managerial cadres. Or is this component of a new type of aircraft just too big an item for that professional obligation of the engineering community to address at the level of certification?

The reason I am (and I hope not impolitely) pointing back to the question is that, Congress even before the new one is seated, and certainly in the next Congress opening in early Jan next year, is going to revisit FAA structure and process. Sensing that it's easy enough to wear out an SLF/atty welcome, all I'll say here is that many a legislative project ends up doing more actual harm than good, or gives the false appearance of progress when there isn't any progress in fact, and so problems grow worse. I don't work on the Hill but it's part of something...something.

infrequentflyer789 20th Dec 2020 17:33


Originally Posted by WillowRun 6-3 (Post 10950611)
Okay, I get that SC's are routine or mostly so in context of rapidly advancing technologies and engineering techniques.

Debateable whether or not the LiON batteries were a new or advancing technology, certainly to an outside observer they look like an extant tech that was new to transport aircraft, and was thought at the time by many to be too risky to use in that context. Now, same can be said of FBW back in the 80s when it made the move from military to civilian transport, but A did a heck of a lot of work on FBW to mitigate risk, and (again, to an outside observer) it isn't clear that B did anything significant to the battery tech to de-risk it.


What still seems like a question worth addressing (and I'll say "why is it worth..." in a moment) is whether the SC for the batteries turned out so badly that
Entirely possible that the SC itself was fine and that the compliance was wanting (cf. MCAS). SC is at https://www.federalregister.gov/docu...y-installation I believe. Notably it states that:

(2) Design of the lithium ion batteries must preclude the occurrence of self-sustaining, uncontrolled increases in temperature or pressure.
Which evidently wasn't precluded,and also:

(3) No explosive or toxic gases emitted by any lithium ion battery in normal operation, or as the result of any failure of the battery charging system, monitoring system, or battery installation not shown to be extremely remote, may accumulate in hazardous quantities within the airplane.

Which is clearly being addressed by the venting system. The venting system that was added after the in-service failures...


SMT Member 20th Dec 2020 18:31

One obvious solution to culture change would be to end all financial or productivity based bonuses for each and every employee of Boeing, from the board down. If a bonus system must be in place, reward those who find flaws, makes improvements or creates solutions that enhances safety.

In other words, start living the words "safety first" instead of just speaking and writing them.

GlobalNav 20th Dec 2020 18:43

Not realistic. But it could be realistic to separate those responsible for determining compliance to the safety requirements from the pressures of project schedule and corporate profit. There needs to be sufficient independence between the regulator and the regulated. This can be done even with delegation, as long as nothing the DER does is immune to regulator technical oversight and that a determination of incompetence or dishonesty disqualifies the DER. The DER’s most valuable asset, in addition to technical competence, is trust.

Snyggapa 20th Dec 2020 21:34

I am pretty sure there is a Dilbert cartoon or similar where the people rewarded to find bugs ended up in league with the coders to find a "mutually beneficial outcome".

I think it has to be cruder and harder to manipulate - like a salary or bonus multiplier that contains elements like "deaths due to design or manufacture failure" which can immediately set the multiplier to zero , number of recalls / airworthiness directives / other violations which can massively reduce it, etc.

I agree with the general principle of rewarding the design, manufacturing maintaining of safe aircraft - it just needs to be careful to promote the desired outcome not just something else to be manipulated. Arguably my proposal should, in a a fair, world lead to management implementing yours :)

unmanned_droid 21st Dec 2020 22:08


Originally Posted by Big Pistons Forever (Post 10899507)
I find it very easy to believe that Boeing cut corners. What is unbelievable to me was the fact that Boeing used the supposed automated control of the shim process as justification for reducing the number of QA personnel. The drip drip drip of examples of corporate malfeasance is truly scary.

Now if there is a crash of any newer Boing due to a significant design or manufacturing flaw, I have to think Boeing in its present iteration is finished.

Apologies, only just catching up on this thread.

The reduction in QA personnel was almost certainly part of the business case for the introduction of that piece of equipment. It is almost inevitable that personnel are reduced with the introduction of major new equipment. Claims will be made about person hours saved by the introduction of the equipment and they will be banked in the business case payback timetable.

Different companies have different payback schedules. One company I worked at was 1 year almost non-negotiable. Introduction of any new equipment was incredibly difficult and it showed. Another company was 3 years, and far more realistic for larger capex.

paulross 22nd Dec 2020 09:51

Snyggapa that is the Cobra effect: https://en.wikipedia.org/wiki/Cobra_effect

Dave Therhino 22nd Dec 2020 23:43

Sorry for the delay, tdracer.

I think you are right that all of the in-flight events since the fix have been contained single-cell events.

WillowRun 6-3 23rd Dec 2020 18:09

787 production move
 
Seattle Times now reporting, Boeing has announced it will move all 787 production to South Carolina by mid-March of 2021, a number of months earlier than it previously had described. Article by ST aerospace reporter Dominic Gates.

Big Pistons Forever 24th Dec 2020 16:09

No surprise there. This is a result of company chiefs that care more about union busting than making quality airplanes.....

esscee 25th Dec 2020 09:31

If the 787 production is moving to South Carolina, then as there were some serious problems regarding quality control and adequate supervision over recent times at that facility, there may be more trouble in store for the next few years.

JLWSanDiego 25th Dec 2020 18:02

Or it may solve the problems they have had

fokker1000 27th Dec 2020 15:20

Haven't read this entire thread, so forgive my possibly naive comment.

Airbus are built in a part of the world which is very regulated, and many of it's governments are centre left... So if a person on the production line, or in the engineering dept etc. sees a possible fault, or a short cut too far to increase profits over safety, they would have no problem with raising this issue up the chain of command.

If a similarly minded person raised a concern elsewhere around the globe, they may not dare raise a reasonable concern for fear or being demoted, sacked etc.

The company I work for has a totally open culture to reporting absolutely anything that might compromise safety.


All times are GMT. The time now is 19:43.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.