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Is there an avionics guy on here who can tell me why?


Oldguy

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So I am redoing the interior of my plane, and I keep coming across wires, antenna cable, and connectors tied up in plastic bags or terminated in a blunt terminator. I found the cabling for the Skywatch antenna still in the plane, and it was removed sometime in 2009 or 2010!

So the question referred to in the title is why doesn't the dead wiring get pulled out when a piece of equipment (avionics, instrument, etc.) get removed? I have CBs on my panel for equipment no longer there, but we had to put in additional ones when we did the Aspen installation. I have counted at least three plastic bags covering wiring rolled up and zip tied. There are at least two antenna cables I have seen still running up to where their antennas used to be. And there is a cannon plug behind the panel where wires come into one side and then they are all terminated about 2" past the other.

Is it because we Mooney owners are such CBs we won't pay for the time to have it pulled, or is it something else? I now understand why I see pictures of people redoing their interior and it seems like they must have no avionics compared to what I have - they pulled the wire or had everything rewired.

So what is the estimate for having a J rewired to clean everything up? Asking for a friend...

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I am sure tech will come up with various reasons why but I believe cost could be a factor mainly for simple upgrades when owners didn’t want to pay for extra time needed for clean install.

We often hear here about quotes how much time is needed for certain job and often label that as highway robbery and the like.

 

I’ve noticed some of your issues on my plane and while installing GTX335, I’ve decided for a new RHS panel layout and rewiring new CB and such. I’ve removed all unnecessary harnesses and cables to gain some useful load.

One thing I’ve noticed is some original wiring terminated with plastic caps was in place for future installs and was never used… it went from CB panel to top of center panel by radios and I’ve used to run power for new installation.

Wire was properly marked with Mooney p/n and was easily traceable as per schematics. My IA and I were pleasantly surprised with it.

All of the cleanup work was done myself hence it didn’t cost me anything and I had a pile of wire and connectors for recycling.

 

Good luck.

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The plastic bags are common practice to preserve the connectors in case they're used in the future.

Whether it's the CB owners just not paying for the time to clean things up or shops not bothering to spend the time to clean things up is anybody's guess, but my bet would be the shop bids a job and saves as much time as possible doing the job.   Pulling stuff takes time, so, it gets left instead.

It can be a pain to pull old stuff depending on how it's routed and bundled with other wiring, which is why it often gets left behind.

 

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Its only something that even gets considered when you re-do the entire panel and thus almost everything is re-wired to new equipment. But this is not the norm. Many owners visit their avionics shop to add a box at one time and then another later on and the shop will quote you the best rate they can unless you ask them to clean up/remove old wiring etc. They're going to wire up your new box as easily as they can. Look at all the threads here on MS that ask how much will it cost me to install this or that they're asking how cheaply can that new box be installed. Typically, panels that are built one box at time end up with spaghetti mess of wiring  behind the panel from being patched together for each new box rather than getting fresh clean wrapped wiring assemblies like those that your plane had when it left the factory and also as typically done when a complete new panel is installed.

Edited by kortopates
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It’s laziness. I asked my shop to remove stuff like this.

715e2d5bd8118b552ad3f45481ebbd34.jpg

There may be some extra wires for shops that do a little forward thinking. And run a series of wires for future use. Like the white wire bundle by the left rudder in the picture above.

What I can’t stand is crap like this. How hard was it to bundle it up?

7859fa9ba4c73e509d02f7919eff29a7.jpg

When Bruce Jaegar did my interior, I took the time to properly route and safety any wire bundles running through the sidewalls.

bd940b0c7d8d72732208c9523cf6ed5b.jpg


Sent from my iPhone using Tapatalk Pro

Edited by Marauder
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The time (cost) it takes is the main factor. It takes time to understand what wires to take and what wires not to take out. 

 

The cleanest or less cluttered behind the panel aircrafts are aircraft that had no modifications at all with the original avionics . 

The 90s and 00s were brutal for clutter where original modern avionics required a lot of wires.  

More recently , one or 2 wires like RS232 or ARINC do the job 

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Like others have said, time = money. Want a new "Box" installed? old wire gets cut, new Box, new wires go in...do this several times and you end up with a bunch of "Dead" wires going every where. I've removed a bunch from mine when I had ALL of the interior out a few years ago, and there is probably more that could come out if I felt like chasing them down

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Couple of pics from my most recent project 

430 install from avionics shop in CA.  No labeled routed or harnessed cables.  The only ones with labels are those I did when installing an audio panel and I didn’t have the time or energy to fix it all.44F99835-14AA-4F18-B8A7-6D5A8C0A814D.thumb.jpeg.be8dc11afdd021535a32b894db5a71f6.jpeg

 

Just the start of the collection of unused / orphan wires I took out.  I have three more piles.  Mind you that some of this was used for the removed equipment and I removed 85% of the Remaining RG-58 ... but I will say that I’ve spent as much time removing orphan wires and reorganizing as I have installing.  I also found a baby rattle behind the side wall.  No idea on that one. 

4AFC1FD2-AC1F-485F-B61F-E8969C6A0227.thumb.jpeg.f16f1b787edded7e735db3094a0627ef.jpeg  
 

I will say I don’t blame the shops for terminating things the way they do.  I removed a DME connector that was neatly tied up in a plastic bag for 20+ years.  Proper organization does take a ton of time though.  Time most of us aren’t willing to pay for. 

 

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One more thing that makes removing the old wires a pain :   D-sub connector pins are easy to put in but a pain to remove and try to do that behind a Mooney panel !!.

We all bash the Bendix King connectors for being dated but they are easily removed or put in.

I considered the Approach Fast Stack concept but i never made the jump. (mixed reviews and worried about changes and being able to upgrade)  

I am hoping at some point all wires will go and everything will be bluetooth. But i doubt that will happen anytime soon. Something can be done with some sort of "service pigtail"    

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I'm sure we won't get to see all the wires gone and replaced by wireless, but I do think that modern serial protocols requiring just two small wires are a major win (think old style GRAY code connections from altitude encoder to transponder).  If we could get open protocols running over those wires, that would be great, thanks.

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All of the above comes to mind here, capped off with the unlabeled fuse holders indiscriminately tied up under there.

Coming from a history of complete wire/rewire down to adding an aux power jack, as well as a much larger dose of troubleshooting and repair, I offer the following:

I always pulled as much wire, connectors, fuses, etc... Every time, if I could, my rule to anyone was "if you can do it in 15 minutes, do it. 

Here is the rational, If we trim the unused harnesses as far as reasonably practical when we are deep in the panel during any upgrade, trim it,cap it with shrink.

During the next inspection, generally the other ends are exposed and can receive the same treatment. 

Then when you deep dive into the interior (or what ever reason), much of the remainder is accessible.

I've found clipping several era's of tyraps and removing the unused wiring can reveal some other potential issues as well.

Know this from personal experience, be very careful with every wire you cut, I just helped a shop work thru this lesson.. 

A great deal of how I help people is with the aging harnesses, when a box fails, often times it is caused by something outside of it.

The easier the wiring is to navigate, the easier, and cheaper, the aircraft is to maintain.

I'm starting a new thread, Post some "up panel", and "exposed panel" shots of your aircraft.

Edited by Bob Weber
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48 minutes ago, INA201 said:

Is it inappropriate thread drift to include the following question? “What is the best solution to cleaning up old, unused, outdated wiring and such?”

Not in my mind. I think it is a great segue.

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Another factor to “explain” .... even though there are a lot less wires (one or two required instead of the ten needed before) , equipments talk to each other a lot more than they used to .  

Take a 430W for example .... it is connected to a lot more than a KX155

Look at a G5, the wire harness seems simple on paper but in practical, the routing of the can bus is complex

with plenty of time , you can do the best you can but it takes time. 

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6 hours ago, tmo said:

I'm sure we won't get to see all the wires gone and replaced by wireless, but I do think that modern serial protocols requiring just two small wires are a major win (think old style GRAY code connections from altitude encoder to transponder).  If we could get open protocols running over those wires, that would be great, thanks.

Yup, networking is definitely the way to do it, but I'm a bit dismayed that there's such a mix of CAN/429/232/etc., etc.   At the rate that General Aviation adopts technology I doubt that a decent avionics network strategy will be developed in my lifetime, especially when some major vendors are trending toward closed systems rather than open.

The rest of the world stopped using RS-232 and d-sub shell connectors a couple of decades ago, and it's only now really getting good use in General Aviation avionics.

IMHO you don't want wireless connectivity between boxes that can be wired, for quite a number of reasons, reliability being a big one.

Edited by EricJ
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You put something in and it works.   Do you really want to spend some time cutting and possibly screw something up and spend a half day troubleshooting?     I think I spent a half day figuring out what was going on with the wiring and most of mine is factory.   But yes bunch of stuff has been cut out.

 

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23 hours ago, Bob Weber said:

All of the above comes to mind here, capped off with the unlabeled fuse holders indiscriminately tied up under there.

Coming from a history of complete wire/rewire down to adding an aux power jack, as well as a much larger dose of troubleshooting and repair, I offer the following:

I always pulled as much wire, connectors, fuses, etc... Every time, if I could, my rule to anyone was "if you can do it in 15 minutes, do it. 

Here is the rational, If we trim the unused harnesses as far as reasonably practical when we are deep in the panel during any upgrade, trim it,cap it with shrink.

During the next inspection, generally the other ends are exposed and can receive the same treatment. 

Then when you deep dive into the interior (or what ever reason), much of the remainder is accessible.

I've found clipping several era's of tyraps and removing the unused wiring can reveal some other potential issues as well.

Know this from personal experience, be very careful with every wire you cut, I just helped a shop work thru this lesson.. 

A great deal of how I help people is with the aging harnesses, when a box fails, often times it is caused by something outside of it.

The easier the wiring is to navigate, the easier, and cheaper, the aircraft is to maintain.

I'm starting a new thread, Post some "up panel", and "exposed panel" shots of your aircraft.

How about panel porn? I mean the real stuff that should not be seen.

Like these:

 

IMG_4273 (2).jpg

IMG_4274 (2)_LI.jpg

IMG_4275 (2).jpg

IMG_4278.jpg

 

Or patch work where an antenna was removed:

IMG_4276.jpg

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On 11/19/2019 at 8:54 AM, Marauder said:

Another pet peeve of mine was the number of inline fuse holders that were under the panel. Most of these were removed in favor of panel mounted circuit breakers.
 

I agree on this one.

It's very hard to identify those as on my plane were inside bundled wire. Most were removed for CBs . One thing that REALLY freaked me out was most of avionics was protected by only Avionics master Switch-breaker. All of the wires were joined with long screw driven through all the ring terminals and "isolated" with electrical tape! Crazy!

I cut the new panel and I've added a number of CB for current and future upgrade - and rewired existing/new avionics through CBs.  

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This is a 340A breaker panel, look middle right hand side at the loose ring terminal. That is the feed line to the avionics buss.

On a routine ground check over the phone we were going thru the power up stage, when he hit the avionics master he hesitated and then said "it does this from time to time".

I told him to power down and guided him to this in less than an hour, in Australia.

He routinely flew in the soup with his family.

I recommended he replace the heat damaged section of wire, and the breaker switch.

I was amazed how well a high res picture can put my eyes half way around the world in near real time.

look for the missing screw, things in this area of your aircraft do not react well with loose screws.

Another thing to pay attention to is a few of the screw heads on the other breakers are discolored, check each screw for tight.

We started this project looking for an autotrim induced pitch issue.

I got to hear my favorite thing to hear, "It fly's better than ever now" Mate!

Bob Weber webairconsulting.com

hall of flame.jpg

Edited by Bob Weber
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