pygmalion
Topic Author
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News About A380 Wiring Problems

Sat Jul 01, 2006 12:01 am

Reuters has a story today about the wiring issues on the A380. From the article, it appears EMI (electro magnetic interference) is the problem. Ouch, hard to fix. You must either move wires farther apart or shield them somehow. First requires re-routing, other adds weight. Fair use snippet:

"In the plane, power and signal cables have to be a certain distance apart to avoid electro-magnetic interference. Cables also are strapped together in bundles called harnesses.

When testing shows that shaking or movement in flight may shift a cable close enough to another to cause interference, that cable must be moved.

Since there is no slack in the plane's 500 km of wiring, changing the position of one cable could require a cascade of changes in the positions of other cables or a whole new harness.


Multiply that by the number of aircraft already assembled -- 13 excluding the two built solely for static testing -- and changes can take thousands of hours of labour to complete."

Link to article "How Airbus cabling unwired a European giant"


:
 
zvezda
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 1:16 am

Wow! This is more grim than I thought. The new schedule appears to be a SWAG. I would not lay bets on how many WhaleJets will be delivered in any given year -- except to bet zero in 2006. For each version (one or more per airline), Airbus must design a set of harnesses, put them together on the airplane (much more difficult once it's already assembled) and then test them. So, all of them failed the testing. That means a new design, a new round of installation, and a new round of testing. Interatively, until all the tests pass. There is no way to predict how many iterations will be needed.
 
leelaw
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 1:44 am

Quoting Zvezda (Reply 1):

Additionally, in the minutes of leaked audit committee meeting of May 12th, Mr. Humbert said that the extent of remaining "cabin integration" problems can't be adequately assessed/confirmed until the "cabin long flight tests" commence in August 2006. Thus, the "production audit" commissioned to assess the status/condition of A380 program which was the basis of the June 13th delay announcement, got them to the worst case scenario Mr. Humbert described on May 12th, before the triggering event he was contemplating to make the estimates even happened. That can't be soothing news to already nervous customers.

http://82.152.52.97/eads.pdf
Lex Ancilla Justitiae
 
jacobin777
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 1:45 am

Quoting Zvezda (Reply 1):
Wow! This is more grim than I thought. The new schedule appears to be a SWAG. I would not lay bets on how many WhaleJets will be delivered in any given year -- except to bet zero in 2006. For each version (one or more per airline), Airbus must design a set of harnesses, put them together on the airplane (much more difficult once it's already assembled) and then test them. So, all of them failed the testing. That means a new design, a new round of installation, and a new round of testing. Interatively, until all the tests pass. There is no way to predict how many iterations will be needed.

I still think that once they get their "house in order", they will be able to optimise and solve this problem....barring any new unforeseen situations, I think Airbus' A380 plane delivery will be on schedule.. checkmark 

Now big the question is, will they be getting anymore new orders soon?
"Up the Irons!"
 
elvis777
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 1:49 am

Hi Pygmalion,

Interesting article. Zvesda is right an EM problem can be quite difficult to resolve. Why were the french blaming the hamburg folks for this delay?

Elvis777
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SInGAPORE_AIR
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:00 am

Quoting Zvezda (Reply 1):
The new schedule appears to be a SWAG

What's S.W.A.G.?!

Anyway, dire news. One wonders what else can go wrong.

The Reuters article is very good though.

From the Audit Comittee's minutes, we have to wait until August 2006 before we know if there are any more delays.

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leelaw
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:02 am

Quoting Singapore_Air (Reply 5):
What's S.W.A.G.?!

Acronym for: Scientific Wild-Ass Guess
Lex Ancilla Justitiae
 
Dougloid
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:07 am

Apparently what this report is saying is that there's unacceptable crosstalk and rf spillover in the wiring bundles as built. My guess is that they were built and tested for continuity and got the stamp o' approval.....bad move.
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
GGpillow
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:08 am

did Boeing have these kinda problems with the launch of the 747 program?
 
jacobin777
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:08 am

Quoting Singapore_Air (Reply 5):
Anyway, dire news. One wonders what else can go wrong.

The Reuters article is very good though.

From the Audit Comittee's minutes, we have to wait until August 2006 before we know if there are any more delays.

why the ""200"? We all know it's going to be early 2007...I even signed up to fly on the Big Beast on SQ's website.. biggrin 
"Up the Irons!"
 
SInGAPORE_AIR
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:09 am

It's 2007! The 7 is made up of Airbus logo.

Sorry, it was a 2 minute MS Paint job
Anyone can fly, only the best Soar.
 
jacobin777
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:12 am

Quoting Singapore_Air (Reply 10):
It's 2007! The 7 is made up of Airbus logo.

Sorry, it was a 2 minute MS Paint job

ahhh..I get it..if you added one more Airbus logo across, it would have been easier to see.. Smile
"Up the Irons!"
 
pygmalion
Topic Author
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:15 am

Quoting Elvis777 (Reply 4):
Why were the french blaming the hamburg folks for this delay?

Because they could?? Okay, maybe that's too harsh.  Yeah sure

I don't know where/who designed the bundles/harnesses. How split up is the engineering between the two countries? How well defined were the EMI requirements provided to the engineering design teams? The company I work for has a central EMI standards group... the wire installation design teams take those standards and layout the routing/wire installations. There are always a few "discoveries" in test but this seems way, way beyond the normal gotchas. So it could be that the standards weren't clear or it could be that they weren't followed well enough. Or that the standards were flat out bad... none of those sound promising. Adding separation to installed wiring is a nightmare. All the allotments for space and separation are done really early in the process just because of that.
 
Beaucaire
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:17 am

http://www.spiegel.de/wirtschaft/0,1518,424520,00.html

This article says Forgeard and Humbert -both - are to leave their positions...
Please respect animals - don't eat them...
 
pygmalion
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:21 am

Quoting GGpillow (Reply 8):
did Boeing have these kinda problems with the launch of the 747 program?

No not really. The wiring on older airplanes like the 747 is less bothered by EMI. As you night imagine, static/noise on a FBW airplane is more a problem than on the older less digital ones. There were a few noise issues on the 777 but nothing that couldn't be fixed without any delays in the schedule. This is something you test for... so you leave some time to fix anything found.
 
airmailer
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 2:24 am

Quoting Elvis777 (Reply 4):
Why were the french blaming the hamburg folks for this delay?



Quoting Dougloid (Reply 7):
Apparently what this report is saying is that there's unacceptable crosstalk and rf spillover in the wiring bundles as built. My guess is that they were built and tested for continuity and got the stamp o' approval.....bad move.

Where was the WhaleJet designed again?
 
Dougloid
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 3:21 am

The other question I have about the systems in use in the A380 is, are they using multiplexing, i.e., using one pair of wires to do a bunch of different tasks?
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
baron95
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 3:37 am

Could this impact certification?

As I understand it, the Reuters article claimed that "during flight", because of "flexing and movement" of the airframe, certain wires or bundles shifted into position that caused EMI problems.

That seems to be a non-deterministic problem (some times happens, sometimes not, no specific conditions to replicate, etc). This means uncertainty.

FAA and European Certification authorities frown on uncertainty of behaviour.

Would they certify the plane until this is totally tested? Would the August series of flight tests mentioned by Gustav be designed to test this?

If the problems are interfering with any of the planes basic systems - it won't be certified till fixed, retested, passed. If it is in things like cabin lighting and entertainment systems, I still think there is a good chance of it not being certified until the regulatory bodies are satisfied that the problem won't spill over to other systems.

Add it all up, if problems are found in the August flight tests, I think there is little chance of the A380 being certified in 2006.
Killer Fleet: E190, 737-900ER, 777-300ER
 
Lumberton
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 3:44 am

Quoting Beaucaire (Reply 13):
This article says Forgeard and Humbert -both - are to leave their positions...

Don't read German, Beaucaire, but is this a certainty? I haven't seen any other reports--yet.
"When all is said and done, more will be said than done".
 
baroque
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 3:49 am

Quoting Pygmalion (Thread starter):
Reuters has a story today about the wiring issues on the A380. From the article, it appears EMI (electro magnetic interference) is the problem. Ouch, hard to fix

But presumably nothing to do with the dreaded aluminium/aluminum?
 
deltadc9
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 5:00 am

Quoting GGpillow (Reply 8):
did Boeing have these kinda problems with the launch of the 747 program?

Every plane has some wiring problems, but this is off the hook.

Quoting Dougloid (Reply 16):
The other question I have about the systems in use in the A380 is, are they using multiplexing, i.e., using one pair of wires to do a bunch of different tasks?

That is a very very good question, also, what is the redundancy? I would assume 3 would be the number, the Space Shuttle has a rudundancy of 5.

Quoting Baroque (Reply 19):
But presumably nothing to do with the dreaded aluminium/aluminum?

Now they have two problems EM and the inflexability and danger of AL wiring installations. This is so not good.
Dont take life too seriously because you will never get out of it alive - Bugs Bunny
 
elvis777
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 5:11 am

Beucaire,

Why would they want to cut the herman CEO head off. Are they blaming him for the delays as well. If so , it appears forgeard has done a masterful job of spinning this.

Peace

Elvis777
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okelleynyc
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 5:14 am

This may be a stupid question, but I wonder if any electrical or material engineer out there can answer this:

Is there any difference between Aluminum and Copper when it comes to propogating EMI? Or is it totally an independent issue?
Just give me my Vario, my Ozone Mojo and a gorgeous day of soaring.
 
787engineer
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 5:28 am

Quoting Zvezda (Reply 1):
So, all of them failed the testing. That means a new design, a new round of installation, and a new round of testing. Interatively, until all the tests pass. There is no way to predict how many iterations will be needed.

I didn't see anywhere where the article mentioned that ALL of them failed testing. . .

Quoting Jacobin777 (Reply 3):

Now big the question is, will they be getting anymore new orders soon?

I'm still confident that with good performance numbers, the A380 will get a couple orders during it's first year of production. Low production rates will obviously hurt sales, but once they get everything sorted out Airbus should be able to increase production.
 
ikramerica
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 5:40 am

Quoting Pygmalion (Thread starter):
When testing shows that shaking or movement in flight may shift a cable close enough to another to cause interference, that cable must be moved.

Since there is no slack in the plane's 500 km of wiring, changing the position of one cable could require a cascade of changes in the positions of other cables or a whole new harness.

So there is enough slack to wiggle close to each other, but not enough to "tie them up" apart from each other?

Quoting DeltaDC9 (Reply 20):
Every plane has some wiring problems, but this is off the hook.

Sounds a lot like wiring problems some automobiles go through when new models come out. Usually, they can just add insulation or reroute the harnesses since the runs are short and access is easy.

The same problems happen when wiring a home theater. I've wired a few houses for whole house audio, video and data and had to deal with this, and I had a professional company do my house years ago before I knew how to do it myself, and they FUCKED it up royally, getting feedback in speakers and noise in audio runs due to proximity to power lines.

It's unfortunate that Airbus let this problem slip through. It will be hard to fix, but it is fixable.
Of all the things to worry about... the Wookie has no pants.
 
pygmalion
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 5:59 am

Wire bundles rarely, if ever, wiggle much. Thats just asking for fatigue breakage and chafing of insulation. You quoted the news article snippet in my post. Reporters are not the best at technical discriptions. EMI is not normally a function of wire movement. Changes in power and current in the wire create radio noise that can be picked up in other wires... if those other wires are signal or digital signal cables and poorly or insuffciently shielded... noise can create or change readings and/or prevent data transmission in the wire. As some one stated above, unstable readings or data are frowned upon by the regulatory agencies. Another issue is that wires and or the shielding can act as an antenna and the problems can crop up far away from where its generated. It can be tricky to solve. IFE with all the video and audio signals can cause problems. Mostly you try not to generate any noise and you try to shield equipment or make them resistant to its effects. Make changes... then test, test and test again to prove the design is robust. AIrbus has the talent to fix it... but its not simple and I am not that surprised they have a long delay if they have significant EMI issues.
 
ikramerica
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 6:20 am

Quoting Pygmalion (Reply 25):
You quoted the news article snippet in my post. Reporters are not the best at technical discriptions.

Yeah, I know. That was the point. The whole reasoning sounded suspect because that just isn't how the problem happens. I was pointing out the BS of those two sentences.

What it sounds more like is that the plane was designed for copper. When they went to aluminum, it increased the thickness of the wire. That means that wire becomes closer to other wire, and either insulation needs to be thicker or the spacing needs to be increased. Problem is, there may not be room for either.

And this would really come to light during flight testing (or ground testing), as the extreme test conditions would push the power levels high enough to cause interference in the data cables. In normal use, you might not see it. But in an emergency, the last thing you want is further loss of control.

I've heard plenty of EMI in headphones on certain boeing aircraft, where the IFE cables were obviously run too close to power cables at some point in the jet. Obviously, that's not such a huge deal if it's only about IFE. But when it's about control of APU or flight surface operation, it becomes a big deal.
Of all the things to worry about... the Wookie has no pants.
 
AirSpare
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 6:27 am

Quoting Pygmalion (Reply 25):
Thats just asking for fatigue breakage and chafing of insulation.

  

EMI is a bitch but fixable, but it has to be evaluated from start to the end of the signal path, I would not be surprised if it were just wiring. Another worry to me is that the harness have "moved". As pointed out above, chaffing is a major defect. Does anyone remember how many F-16s were lost due to wire chaffing? IIRC, there were also a few lawsuits against GD and the USAF as the F-16 didn't meet contractual specifications on chaffing. Of course the A380 isn't going to perform +9, -6 g maneuvers, but but due it's sheer size, there must me a tremendous amount of airframe flex that will acaberate harness chaffing.

[Edited 2006-06-30 23:29:29]
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jacobin777
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 6:34 am

Quoting 787engineer (Reply 23):

I'm still confident that with good performance numbers, the A380 will get a couple orders during it's first year of production. Low production rates will obviously hurt sales, but once they get everything sorted out Airbus should be able to increase production.

 checkmark ..I agree..but it seems it will take them a while..I assume they have a good grasp of the situation at hand...!
"Up the Irons!"
 
GBan
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 7:08 am

Quoting Lumberton (Reply 18):
Don't read German, Beaucaire, but is this a certainty? I haven't seen any other reports--yet.

The article claims it to be a certainty, but that doesn't necessarily mean much. I find it a bit strange that the article does name Forgeards successor while not saying a word about Humberts successor. The article also explains why Forgeard has to go but does not say a word why Humbert has to go as well. Posssibly a German journalist has gathered the information on A.Net  Wink
 
redflyer
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 7:34 am

Quoting Pygmalion (Reply 14):
The wiring on older airplanes like the 747 is less bothered by EMI

The older 747's also didn't have IFE in every seat. That's got to be a herculean task to wire every seat on a plane designed to carry 500+ passengers.

Quoting Baron95 (Reply 17):
because of "flexing and movement" of the airframe, certain wires or bundles shifted into position that caused EMI problems.



Quoting Ikramerica (Reply 24):
So there is enough slack to wiggle close to each other, but not enough to "tie them up" apart from each other?



Quoting Ikramerica (Reply 26):
When they went to aluminum, it increased the thickness of the wire.

I was told that aluminum expands something like 80% more than copper when a current is running through it. If true, I would imagine that expansion would also play a big role in pushing some harnesses closer to others.
A government big enough to take away a constitutionally guaranteed right is a government big enough to take away any guaranteed right. A government big enough to give you everything you need is a government big enough to take away everything you have.
 
474218
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 7:43 am

Quoting 787engineer (Reply 23):
Low production rates will obviously hurt sales, but once they get everything sorted out Airbus should be able to increase production.

I think you have it backwards, it is the sales rate that sets the production rate. Low sales means low production, no reason to build them if you can't sell them.

Quoting Pygmalion (Thread starter):
Since there is no slack in the plane's 500 km of wiring, changing the position of one cable could require a cascade of changes in the positions of other cables or a whole new harness.

Every type of aircraft I have ever worked on had slack built in the the wire harnesses. Without slack in the harnesses any flex in the fuselage or bending of the wing could pull the wires out to the plugs and can damage the wire by chaffing. Additionally large bends are always built into the harnesses just before the plugs to allow any fluid on the harnesses to drip from the harnesses rather than run in to the in the plugs, where a short could occur .
 
scouseflyer
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 7:44 am

Quoting Redflyer (Reply 30):
The older 747's also didn't have IFE in every seat. That's got to be a herculean task to wire every seat on a plane designed to carry 500+ passengers.

Wireless, wireless, wireless, wireless!
 
zvezda
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 8:31 am

Quoting Okelleynyc (Reply 22):
Is there any difference between Aluminum and Copper when it comes to propogating EMI? Or is it totally an independent issue?

No difference. The Maxwell Equations apply to both. The insulation matters though.

Quoting 787engineer (Reply 23):

I didn't see anywhere where the article mentioned that ALL of them failed testing. . .

The article didn't, but it's clear from the effect on the schedule.
 
drexotica
Posts: 150
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 8:43 am

Question - is the power on the 380 AC or DC? DC usually does much better wrt creating less EMI (r.e., tube-based hi fi systems with DC filaments/heaters). Of course, hanging a noisy motor/pump on the end of a power cable will generate lots of noise.

Do they run power in one bundle, and signal in another bundle? If not, why not? Also, if signal has to cross power, make it a right angle.
N707PA - Best looking commercial aircraft ever.
 
DfwRevolution
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 8:46 am

Quoting Scouseflyer (Reply 32):
Wireless, wireless, wireless, wireless!

This is proving to be a great case study for wireless IFE, but as of yet, Airbus hasn't taken that route as a solution. A wireless system could potentially create other forms of interference, so it isn't necessarily a magic bullete either. The 787 will use wireless IFE, for the record.

[Edited 2006-07-01 01:48:10]
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AirSpare
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 9:17 am

Does anyone know what type of insulation is used? Here is some interesting info from POGO on wire insulation types.

http://pogo.org/p/x/archivecontractover.html#wiring
Get someone else for your hero worship fetish
 
redcordes
Posts: 244
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 9:18 am

This reminds me of a problem that was encountered while installing an audio system in a large public school. We ran thousands of feet of shielded audio cable throughout the school and grounded the shield of each cable as required. Then, we installed all the hardware (amps, speakers, etc.) and found that the audio from a local radio station was "leaking" from the speakers at a very audible level. We disconnected everthing except the speakers and guess what--the audio was still being produced from the speakers (Definitely an "Oh Shit" moment). We had created a BAA (Big-Ass Antenna) with the cabling that produced enough current to drive about 15 speakers directly (albeit at a fairly low volume). We thought it was kind of funny, but the boss sure didn't. The problem turned out to be having various cable shields grounded at somewhat different potentials. As I recall, ideally each of the cable shields should only be grounded on one end and the grounds must be electrically equivalent-- and possibly just one common ground for all the audio cables. We fixed it--eventually. How does this relate to the 380? I'm not sure, but for years afterward when the guys got together and shot the breeze, we would get a whale of a laugh out of it.
"The only source of knowledge is experience." A. Einstein "Science w/o religion is lame. Religion w/o science is blind."
 
aeronut
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 9:27 am

Quote:
Every type of aircraft I have ever worked on had slack built in the the wire harnesses. Without slack in the harnesses any flex in the fuselage or bending of the wing could pull the wires out to the plugs and can damage the wire by chaffing. Additionally large bends are always built into the harnesses just before the plugs to allow any fluid on the harnesses to drip from the harnesses rather than run in to the in the plugs, where a short could occur .

drip loops is what we call them, and there is always extra length. Im used to working on smaller planes, where segregation is a big issue. How is it that an aircraft the size of the a380 is running into these types of problems? There is sooo much room to segragate these cables in the fuselage.

Think each aircraft interior has to go through dedicated EMI testing.
 
OldAeroGuy
Posts: 3886
Joined: Sun Dec 05, 2004 6:50 am

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 9:38 am

Quoting Redflyer (Reply 30):
The older 747's also didn't have IFE in every seat.

One time, Joe Sutter told me that his idea of IFE was to give every passenger a good book.

Quoting Scouseflyer (Reply 32):
Wireless, wireless, wireless, wireless!

I think Joe was on to an earlier form of wireless.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
jacobin777
Posts: 12262
Joined: Sat Sep 11, 2004 6:29 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 10:00 am

Quoting Redflyer (Reply 30):

The older 747's also didn't have IFE in every seat. That's got to be a herculean task to wire every seat on a plane designed to carry 500+ passengers.



Quoting Scouseflyer (Reply 32):
Wireless, wireless, wireless, wireless!

I was thinking the same thing too... checkmark ..it has its challenges, but it can be done..and it would probably save weight too..

Quoting Redflyer (Reply 30):

I was told that aluminum expands something like 80% more than copper when a current is running through it. If true, I would imagine that expansion would also play a big role in pushing some harnesses closer to others.

I don't know too much about aviation electronics, but what you mention depends on whether its "pure" aluminum, aluminum alloy, etc.....expansion coefficients change with different metals/alloys.....

Quoting Aeronut (Reply 38):
How is it that an aircraft the size of the a380 is running into these types of problems? There is sooo much room to segragate these cables in the fuselage.

maybe there isn't as much room as there is perceived to be?
"Up the Irons!"
 
PolymerPlane
Posts: 832
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 10:18 am

Quoting DfwRevolution (Reply 35):
This is proving to be a great case study for wireless IFE, but as of yet, Airbus hasn't taken that route as a solution. A wireless system could potentially create other forms of interference, so it isn't necessarily a magic bullete either. The 787 will use wireless IFE, for the record.

The delay will probably be much longer if they have to certify wireless IFE on A380, on top of the design stage. I even have read that the supplier is not very confident on wireless IFE on the 787.

Cheers,
PP
One day there will be 100% polymer plane
 
Shenzhen
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RE: News About A380 Wiring Problems

Sat Jul 01, 2006 10:18 am

Probably has more to do with the changes that have been incorporated into the airplane during the past year. There is no doubt that many systems didnt work correctly once power was applied, and engineering needed to make wiring changes.

The problems that this causes is that many of the wiring changes may have not been routed in the best possible manner do to the lack of connector space, wiring harness space, time (lots of pressure) and so forth.

I believe the first couple of 747-400 flight test airplanes needed to be nearly completely rewired before they were delivered. Of course there is constantly wire changes that are going on in flight test airplane, when you are certifing an airplane with systems from different vendors.

Cheers
 
474218
Posts: 4510
Joined: Mon Oct 10, 2005 12:27 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 10:41 am

Quoting Aeronut (Reply 38):
drip loops is what we call them, and there is always extra length. Im used to working on smaller planes, where segregation is a big issue. How is it that an aircraft the size of the a380 is running into these types of problems? There is sooo much room to segragate these cables in the fuselage.

I read somewhere, WSJ I think, that the major wiring problem was that they have 13 airframes built and now have to install the wiring. The normal way would be to install the wiring in segments as the fuselage-wing-aftbody are being assembled.

Thanks for reminding me that the harness bend is called a DRIP LOOP.
 
JAAlbert
Posts: 1970
Joined: Tue Jan 31, 2006 12:43 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 11:21 am

I recall that the two air force one 747s had this same problem. The wiring problem delayed entry of the jets into service by several years. Reagan was supposed to get the jets before he left office, but it wasn't until Geo Bush I was almost out of office that they were finally delivered. If Airbus takes as long as Boeing took to fix the president's plane, we won't see the A380 for a few more years.

Anybody remember the problems with airforce one who can shed light on the issue?
 
phuebner
Posts: 240
Joined: Thu Feb 02, 2006 2:37 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 11:27 am

Quoting Jacobin777 (Reply 11):
ahhh..I get it..if you added one more Airbus logo across, it would have been easier to see..

I got it right off the bat.  razz 

It appears that Airbus' problems keep on mounting. I am a Boeing person, but I do feel that Airbus is important to the overall industry. I am a true believer in competition. I hate to see these problems with Airbus arise.
Remember this, Your Body is a temple Not a pull toy!
 
Elite
Posts: 2297
Joined: Thu Jun 29, 2006 6:31 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 11:36 am

Quoting JAAlbert (Reply 44):
If Airbus takes as long as Boeing took to fix the president's plane, we won't see the A380 for a few more years.

And we thought the delay of 6 months was long enough. Years?? It'd be a joke...
 
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STT757
Posts: 13885
Joined: Tue Mar 28, 2000 1:14 am

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 11:41 am

Quoting JAAlbert (Reply 44):
I recall that the two air force one 747s had this same problem. The wiring problem delayed entry of the jets into service by several years. Reagan was supposed to get the jets before he left office, but it wasn't until Geo Bush I was almost out of office that they were finally delivered. If Airbus takes as long as Boeing took to fix the president's plane, we won't see the A380 for a few more years.

Anybody remember the problems with airforce one who can shed light on the issue?

They used so much insultation to protect the wires from the Electromagnetic pulse (im not sure that's the right term) that happens during a Nuclear Detenation that they ran out of room for the wires.
Eastern Air lines flt # 701, EWR-MCO Boeing 757
 
jacobin777
Posts: 12262
Joined: Sat Sep 11, 2004 6:29 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 12:45 pm

Quoting Phuebner (Reply 45):
I got it right off the bat.

oh yah buddy..you think u're smart ey?... Smile

Quoting STT757 (Reply 47):

They used so much insultation to protect the wires from the Electromagnetic pulse (im not sure that's the right term) that happens during a Nuclear Detenation that they ran out of room for the wires.

correct.. checkmark  those planes need a heck of a lot more shielding than a comman civilian aircraft.....

I still see Airbus solving this problem and getting back on schedule..
"Up the Irons!"
 
474218
Posts: 4510
Joined: Mon Oct 10, 2005 12:27 pm

RE: News About A380 Wiring Problems

Sat Jul 01, 2006 12:48 pm

Quoting JAAlbert (Reply 44):
Anybody remember the problems with airforce one who can shed light on the issue?

Same problem Airbus is having with the A380's. Wiring the airframe after it is built takes a lot more time than wiring it when the areas are open a accessible.

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