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Boeing tells FAA it does not believe 737 MAX wiring should be moved

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Boeing Co (BA.N) told the U.S. Federal Aviation Administration it does not believe it needs to separate or move wiring bundles on its grounded 737 MAX jetliner that regulators have warned could short circuit with catastrophic consequences, people familiar with the matter said on Friday. (uk.reuters.com) More...

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ETerryJ
The abysmal CEO is finally out, when will the feckless BOD be replaced -- possibly sued by shareholders and stakeholders, e.g., supply chain folks that have been laid off. Unbelievable! BTW, my company has owned two (2) B-747s, which were great airplanes, so I am not biased against Boeing, per se.
speshulk99
john kilcher 5
Boeing has the chutzpa to tell the regulator??? Unmitigated gall of them, they (the board and CEO)should be eating a fair share of humble pie.
lecompte2
lecompte2 5
Zero credibility here
DGR54Rathborne
DGR Rathborne 4
as i read this , and reflect on all of the other design problems that have been found ( MCAS , Programming )i feel that the FAA is seeking revenge , for Boeing lying and deceiving the FAA , that Boeing could certify their own aircraft . The resulting fall-out and discoveries of Problems , has infuriated the FAA . But while i use the word Revenge , i don't want to suggest that it is unfair . Quiet the opposite . Boeing built a bad Aircraft , knew it and lied to the FAA , efectively damaging their stellar reputation . Rest assured , Boeing will never pull this stunt again ..............DGR
Michel0
Michel B. 5
Boeing has reason for once. The whole thing shouldn't be moved AND STAY ON THE GROUND FOREVER :P
FrankHarvey
Frank Harvey 1
I believe there were five or six incidents of electrical arcing on Boeing 777s which were caused (according to Boeing) by "...incorrect installation of a wiring harness/bundle probably during manufacture".

One of these resulted in an in-flight cargo compartment fire over Australia in October 2017. In that incident "Discharging the fire bottles in the forward cargo space ....had nil effect on this occasion as the source of the electrical arcing was in the sealed zone between the cargo ceiling panel and the passenger floor compartment, not in in the cargo compartment."

See www.atsb.gov.au/media/5774692/ao-2017-101_final.pdf

I apologise if anyone is offended but I am posting the information below twice as I believe it is very relevant to this topic.

According to the investigation into the July 1996 TWA 800 (25 year old 747-100) explosion, a "high voltage" (115/120 volt) wire in the same harness/bundle as a low-voltage sensor wire, over years of airframe operation during which insulation in adjacent wires can chafe, can cause a short circuit which might result in arcing. In the case of TWA 800 such a short-circuit is claimed to have been the source of an electric current which caused a tank-sensor spark which ignited the explosion that destroyed the 25 year old a/c

In 2017 a 4 year old 777-300 in Australia experienced an inflight cargo compartment fire because insulation on a 115 volt wire chafed through against a screw. There were five other incidents of 777 wiring arcing because of chafing. To quote the Incident report "...subsequent investigation conducted by Boeing found that the wire bundle W5279 had been incorrectly routed, likely during aircraft manufacture, and had not been installed as per the design drawings...".


I am under the impression that there may be at least one fly-by-wire control wire adjacent to a high-voltage wire in the harness/bundle under discussion in the NG and Max.
lecompte2
lecompte2 0
Boeing is scary
richardtarr
Richard Tarr 1
This whole thing is now as boring as brexit was .
Nobody is going to fly on this disastrous aircraft
Life support should be discontinued
Boeing are just a laughing stock

speshulk99
john kilcher 2
Unless you own the stock and then the laughter ceases.
baingm
Gary Bain 0
Damn I'm sick of all the Boeing bashing. Boeing has an excellent point and I quote from the article:
"Boeing has noted in talks with the FAA that the same wiring bundles are in the 737 NG, which has been in service since 1997 and logged 205 million flight hours without any wiring issues." Why would the FAA invent an issue with a system that far exceeds their own expected failure criteria? The FAA's "issue" simply makes no sense. There is simply nothing wrong with the 737 MAX that hasn't been or is being addressed. The changes made by Boeing in conjunction with the FAA will make it a great, safe airplane. Y'all act like no other manufacturer has ever made a mistake / bad call / engineering error not to mention general aviation and military aircraft. McDonnell/Douglas, Airbus, Lockheed, de Havilland, etc., etc., etc. all have built defective aircraft resulting in far more deaths than the two MAX crashes. Not that there should ever be any but the nothing will ever be perfect. Boeing is paying a huge financial and reputation penalty for this mistake and in retrospect the resolutions of this error will make it an even greater company. If I were still an active pilot I would fly the 737 MAX in a New York minute. Type rated on 737-200 through 700NG, 757, 767, A320 series. 24,800 hours, 42 years, civilian, military, airline, corporate.
DGR54Rathborne
DGR Rathborne 5
Gary , i have found that almost with-out exception , at least one aircraft in every model type built by all the aircraft manufacturers that you mention , have suffered a major crash . And thanks to Agencies like the NTSB and those in most other advanced countries , we often find out what the devil went wrong . But , when it comes to a manufacturer , designing and selling an aircraft that the company Knows has built in Flaws that are known to be questionable ,,there are very few of those examples . Because of this , this has caused World Renowned Boeing to rightly suffer . It may not be fair , but it just may be necessary ......I'm sorry to say this as i've had great respect for Boeing Aircraft .......But something has gone terribly wrong .........DGR
FrankHarvey
Frank Harvey 1
Hi Gary,

Wiring harness/bundle contents and their routing in an aircraft are not always a trivial matter.

According to the investigation into the July 1996 TWA 800 (25 year old 747-100) explosion, a "high voltage" (115/120 volt) wire in the same harness/bundle as a low-voltage sensor wire, over years of airframe operation during which insulation in adjacent wires can chafe, can cause a short circuit which might result in arcing. In the case of TWA 800 such a short-circuit is claimed to have been the source of an electric current which caused a tank-sensor spark which ignited the explosion that destroyed the 25 year old a/c

In 2017 a 4 year old 777-300 in Australia experienced an inflight cargo compartment fire because insulation on a 115 volt wire chafed through against a screw. There were five other incidents of 777 wiring arcing because of chafing. To quote the Incident report "...subsequent investigation conducted by Boeing found that the wire bundle W5279 had been incorrectly routed, likely during aircraft manufacture, and had not been installed as per the design drawings...".


I am under the impression that there may be at least one fly-by-wire control wire adjacent to a high-voltage wire in the harness/bundle under discussion in the NG and Max.
JMARTINSON
JMARTINSON 1
Nobody is questioning whether or not wiring is a critical safety concern.
cowboybob
cowboybob 1
Unless anyone on this thread designs and certifies aircraft in the USA(or anywhere else in the world for that matter)...I do by the way and not for Boeing...you should clam up as you haven't the foggiest idea of what you are ranting about.

The FAA (or any government agency for that matter anywhere in the world) rarely has the expertise in-house to design(or re-design) an aircraft as has been proven many times over the years. So what this process often boils down to is a Q&A against some often very poorly written and conflicting regulation(s)and then a negotiation over the dispute to reach an outcome. Happens everyday around the world on every make and model of aircraft.

Government authorities can(and often do) play "what-if" well beyond any sane threshold of probability...if you understand 6-sigma, then you have some idea of what this means. And while Boeing clearly did not do themselves one single favor in handling this situation, they are obviously now in a "penalty box" which has nothing to do with the original technical issue being examined. Imagine a congressional committee if you will trying to take someone to task over some issue which none of the representatives on the panel have one ounce of knowledge about (hint: they're mostly lawyers and other people who couldn't get real jobs)...that's your FAA methodology...they're not happy Until you're not happy. Any less qualified individual who can spin a tale, can ask more questions than a wise man can answer.

The Max won't fail because it is not an airworthy aircraft, it will fail from government underachievers suddenly trying to become overachievers. Many other government agencies around the world view this as a get-out-of-jail-free-card to cover their own tracks of mishandling airline operational certificates and training under their purview as they have plenty of skeletons in their closets...make no mistake about that. Their are many airlines around this world I would not fly on for a free ticket no matter what aircraft they are flying.

Try a little critical thinking outside the lamestream narrative and you might have an epiphany.
WilliamMonti
William Monti 0
Why did US carriers not suffer failures ? Can anyone tell us ?

Once they are back in service, soon I hope, I will fly in them after all the Flight Deck Crews do not like to suffer fatal accidents.
bobinson66
bobinson66 8
I am not involved in the aircraft industry so there are others here who can likely provide a better answer, but in my observations of press reports and blog entries, here is my takeaway (so I might be off a bit):

1. Lion Air (Indonesia) and Ethiopian Airlines do not require as much pilot training as American carriers.
2. Lion Air and Ethiopian Airlines purchased a rather stripped down version of the 737Max8. It was surprising to me that Boeing allowed a product out the door that depends on one or two Angle of Attack sensors without redundant systems. American carriers purchase a more robust avionics package with more redundancies and thus the MCAS programming has better data to work from.

In my opinion, safety equipment should be standard rather than optional.
DGR54Rathborne
DGR Rathborne 5
In your opinion ," safety equipment should be standard rather than optional " . Thats the most rational comment of recent times . You are absolutely correct , and it is well stated . Thanks for posting your observation ....DGR
JMARTINSON
JMARTINSON -1
Is it rational to think that Boeing knows what every airline on the planet needs better than the airline itself?

That is not rational, it's egotistical. It's also wrong.
WilliamMonti
William Monti 4
Thank you. One would hope the Regulators would own up to their short comings.

Yes safety equipment is not an option, it was not an option in my industry - nuclear power for propulsion or electricity production.
JMARTINSON
JMARTINSON 0
So there are no budget or time constraints in the nuclear power industry? No compromise whatsoever?
JMARTINSON
JMARTINSON 1
Your second point is off my more than just a bit. Below is a copy/paste job direct from Boeing's web site because they can explain it much better than I can.

On every airplane delivered to our customers, including the MAX, all flight data and information needed to safely operate the aircraft is provided in the flight deck on the primary flight deck displays. This information is provided full-time in the pilots’ primary field of view, and it always has been.

Air speed, attitude, altitude, vertical speed, heading and engine power settings are the primary parameters the flight crews use to safely operate the airplane in normal flight. Stick shaker and the pitch limit indicator are the primary features used for the operation of the airplane at elevated angles of attack. All recommended pilot actions, checklists, and training are based upon these primary indicators. Neither the angle of attack indicator nor the AOA Disagree alert are necessary for the safe operation of the airplane. They provide supplemental information only, and have never been considered safety features on commercial jet transport airplanes.

The Boeing design requirements for the 737 MAX included the AOA Disagree alert as a standard, standalone feature, in keeping with Boeing’s fundamental design philosophy of retaining commonality with the 737NG. In 2017, within several months after beginning 737 MAX deliveries, engineers at Boeing identified that the 737 MAX display system software did not correctly meet the AOA Disagree alert requirements. The software delivered to Boeing linked the AOA Disagree alert to the AOA indicator, which is an optional feature on the MAX and the NG. Accordingly, the software activated the AOA Disagree alert only if an airline opted for the AOA indicator.

When the discrepancy between the requirements and the software was identified, Boeing followed its standard process for determining the appropriate resolution of such issues. That review, which involved multiple company subject matter experts, determined that the absence of the AOA Disagree alert did not adversely impact airplane safety or operation. Accordingly, the review concluded, the existing functionality was acceptable until the alert and the indicator could be delinked in the next planned display system software update. Senior company leadership was not involved in the review and first became aware of this issue in the aftermath of the Lion Air accident.

Approximately a week after the Lion Air accident, on November 6, 2018, Boeing issued an Operations Manual Bulletin (OMB), which was followed a day later by the FAA’s issuance of an Airworthiness Directive (AD). In identifying the AOA Disagree alert as one among a number of indications that could result from erroneous AOA, both the OMB and the AD described the AOA Disagree alert feature as available only if the AOA indicator option is installed.

Boeing discussed the status of the AOA Disagree alert with the FAA in the wake of the Lion Air accident. At that time, Boeing informed the FAA that Boeing engineers had identified the software issue in 2017 and had determined per Boeing’s standard process that the issue did not adversely impact airplane safety or operation. In December 2018, Boeing convened a Safety Review Board (SRB) to consider again whether the absence of the AOA Disagree alert from certain 737 MAX flight displays presented a safety issue. That SRB confirmed Boeing’s prior conclusion that it did not. Boeing shared this conclusion and the supporting SRB analysis with the FAA.

Boeing is issuing a display system software update, to implement the AOA Disagree alert as a standard, standalone feature before the MAX returns to service. When the MAX returns to service, all MAX production aircraft will have an activated and operable AOA Disagree alert and an optional angle of attack indicator. All customers with previously delivered MAX airplanes will have the ability to activate the AOA Disagree alert.
custerisus
d. thayer 1
I think we all know the answer. It's just that everyone seems to be in denial
Jackx9
Don Quixote 0
American Airlines purchased both AOA sensors. Idk about the Lion or Ethiopian MAXs
JMARTINSON
JMARTINSON 2
The number of sensors has always been and it's a good bet always will be two.
shenghaohan
Shenghao Han 0
Looks like there are more holes on Boeing's slice of cheese... Kinda feels bad for Boeing...

I don't 100% agree with Boeing's "it ain't broken, don't fix it" mentality... After all it is "broken" due to not adhering to latest safety regulations...

On the other hand... I do agree sometimes the fire-proofing standards are a bit too vigilant... So...
JMARTINSON
JMARTINSON 1
It's not about if it ain't broke, it's about the possibility of breaking it more (or breaking something else) while trying to fix.
AbieshanG13
It shouldn't be moved. If it does eventually, it may cause an even worse short circuit and possibly kill everyone on board.

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