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Is This Wiring Typical?

Pilotjim77

Well Known Member
I just removed my Garmin 295 GPS from the panel in order to remove my radio, which has been having some issues. I want to get the radio bench tested. This is what the wiring looks like as seen through the panel hole for the GPS:

jxioDNBl.jpg

Exf9zS2l.jpg


I don't like the looks of this at all. I'm thinking I need to address this. Any thoughts on the best way to approach this? I'm not looking to upgrade, just fix and clean this up.
 
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Typical is relative as I have seen this type wiring on a few planes.

Is it what I would want, no and I suspect by your comment neither do you. I would get all those bread bag twist ties you have in the kitchen and start seeing what you can do to bundle things. When you are happy a few zip ties will make it more permanent.
 
No, that is not typical poor workmanship, that is exceptionally poor workmanship:eek:
I suspect you already know that.
First thing is to examine the wire types used.
If okay, then start bundling by destination to see if you have enough to dress and secure properly.
You?ll have to see where it leads in terms of ?can this be saved?.
Good luck
 
I've seen this kind of rats nest on plenty of 50-60 year old Cessnas and Pipers, not on an RV.
 
Ouch.

I would do some exploring and see if the wires are Tefzel, and aircraft connectors are used. Also make sure you can cut power to everything (properly wired master relay) and the plane will continue to operate normally. No glass panel, electric ignition, etc. if all that checks out ok, you can decide if it is ok for your mission.

By the pics you posted the fix would be to pull out a majority of the wires and start over. A big task, but doable.

Would not be surprised if your radio issues are related to the wiring.

Good luck.
 
As another poster pointed out, if the wiring is this bad, check the connectors. Good chance they're neither aircraft quality nor properly installed.

Your wiring looks much like the wiring on my old RV-4 when I bought it...

And when you rewire it, you can color code wires appropriately and generating either a schematic or, my preference, a wiring list.
 
I don?t know...a rather novel way to prevent stress on the connectors by having
each wire act as a support of others. I would refer to the problem solving flow chart before even thinking of messing with this.
Would somebody post the flow chart here for Jim.
Thanks,

R
 
Actually...

Not that I would EVER endorse a rat?s nest like that, just because it?s not ?pretty? does not mean it?s not ?airworthy?...

I have seen many ?airworthy? installations that looked pretty messy to me...

In this case, if it were mine, I?d start over...
 
OK, ugly it may be-----but from what you have posted, it would seem to have been working as is.

If/when you go to tidy it up, be sure not to cause problems----such as pulling out of connectors, chafing wires against sharp edges, etc.

Adding labels to each wire is a good idea, both ends if needed.

For direct point-to-point wires that need to be lengthened, it is usually better to replace than to splice in extra length.

Good luck.
 
If you ever have an electrical problem, it'll be practically impossible to fix it.

My vote is to replace the wiring completely.

I'd start with getting a copy of the installation manuals for all the devices. That'll give you an idea of the way things should be connected, what goes where. Then get a copy of The Aeroelectric Connection by Nuckolls, and then start looking for photos of well-wired RVs right here on VAF.

You'll need a few tools, and the various RV avionics vendors have those. Often there are how-to videos as well.

Make a drawing or spreadsheet or something that you can mark up as you go, to track your progress and to assist you or the next person who needs to figure out what to do if something goes wrong.

Dave
 
I see many posters advocating replacing and tidying the wiring up. Which is a fair call.

But, while it looks terrible, I have to ask the question: Why "fix" what ain't broke?

If you have a problem, then sure, tidy it up as part of the rectification process, but if everything is working now, I would personally leave it be. You're likely to cause more issues and be grounded longer by trying to correct something that doesn't need it - yet.
 
its just a picutre, but it sure looks like a lot of PVC insulation and automotive grade (not pidg) connectors to me. if it is, a complete redo is the only proper solution.

bob burns
RV-4 N82B
 
Is that a stray cleco left in there in the first pic middle, left....:eek: seriously I would feel more comfortable with all of those in wire bundles if I were at the controls.
 
going through quite similar issue in my 4 right now. Was only 4 circuit breakers and switches for the entire plane. then as i started tracing wires I found glass tube type fuses in a holder way behind the panel where you could never see it, then another one on the right wall near the firewall. so the last two days have been spent untangling and tracking wires. I'll admit that I am not making it nearly as perfect and clean as others I've seen as I am anxious to get her back into the air flying, but everything will now be on properly sized circuit breakers and laid out a bit more logically.
 
...and

"...a lot of PVC insulation and automotive grade (not pidg) connectors to me..."

There are many, many flying aircraft out there with "automotive" wiring in them. That in itself has nothing to do with being "airworthy". The same goes for the connectors...

It is about risk and risk mitigation. There are tens of millions of vehicles out there using PVC wiring successfully; the wire doesn't know or care if it's in an aircraft or a car...it will work the same either way.

The main difference is in the perceived risk of one insulator versus the other...and that is something each builder must address and be comfortable with.
 
Shoot fire, it is just wire and until you dive into it you will have no assurance against something there waiting to bite you.

Rip it out and start over - this is not rocket science.

Why have this potential risk constantly banging around in your brain every time you get in the plane?

Carl
 
I've seen this kind of rats nest on plenty of 50-60 year old Cessnas and Pipers, not on an RV.

The fact that you see this on 60 year old planes would seem to indicate that, while unsightly, it doesn't represent an accident waiting to happen nor un-airworthy. I agree that it is not the way most here would do it, I am not convinced that it warrants re-wiring the plane as some are suggesting.

I would do my best to bundle it up the best you can, as that will help with strain relief and help the longevity.

Larry
 
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"...a lot of PVC insulation and automotive grade (not pidg) connectors to me..."

There are many, many flying aircraft out there with "automotive" wiring in them. That in itself has nothing to do with being "airworthy". The same goes for the connectors...

It is about risk and risk mitigation. There are tens of millions of vehicles out there using PVC wiring successfully; the wire doesn't know or care if it's in an aircraft or a car...it will work the same either way.

The main difference is in the perceived risk of one insulator versus the other...and that is something each builder must address and be comfortable with.

+1

The only thing that tefzel provides over PVC is a higher melting point and somewhat less fumes, as well as being somewhat less noxious, during melting. The benefit is better surviveability when there is a fire. Electrical performance is identical. PTFE, tefzel, does provide a lower mutual capacitance, but that provides no benefit in aircraft wiring.

Larry
 
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I agree with Larry. And the fact that it is on a 60 year old plane probably means it evolved, one additional circuit at a time over that 60 years.
 
Not happy about it but the backside of my panel looks not to far away from that currently....(wires and connectors are good)
At least it looks like you used aircraft wire and have some labeled. The OP has a rat nest, automotive wire, no labels and likely no wiring diagram. If I would have done a pre-purchase inspection I would have called that out. However he might be able to tie some of it up and trace and label it to improve it without wholesale removal and redo.

The recent (last few months) EAA Sport Aviation Mag has an excellent article on wiring.
 
Disgraceful

Disgraceful, disgusting, dangerous. I?d make a complete inspection of the rest of the aircraft because that wiring is a dead-set indicator of a totally incompetent builder.
 
Umm...

Disgraceful?...Probably.

Disgusting?...Definitely.

Dangerous?...Questionable.

The aircraft has been flying with that wiring, so the empirical evidence would suggest that it is NOT dangerous...and you should have seen the wiring in my 1957 C-172; it was worse, and that airplane flew 50 years with it that way...

The wiring doesn't need to be "pretty" to be safe, and "ugly" wiring isn't necessarily dangerous.
 
...and you should have seen the wiring in my 1957 C-172; it was worse, and that airplane flew 50 years with it that way...

The wiring doesn't need to be "pretty" to be safe, and "ugly" wiring isn't necessarily dangerous.

Firstly, no Cessna EVER came new out of the factory with wiring like that. I would suggest if your 1957 C-172 had wiring worse than that then it had avionics upgrades/maintenance along the way performed by incompetent avionics technicians.

Secondly, bundling wire runs into looms is NOT about looking "pretty". It's all about organisation and safety. Bundling wires gives them superior support, limits unwanted movement, takes stresses off connections, and greatly reduces the possibility of wires chaffing on the airframe.

To me, dangerous building is about poor workmanship leading to a significantly increased possibility of an adverse outcome. I think that's pretty much what I see in the photo posted by the OP. ;)
 
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The fact that you see this on 60 year old planes would seem to indicate that, while unsightly, it doesn't represent an accident waiting to happen nor un-airworthy. I agree that it is not the way most here would do it, I am not convinced that it warrants re-wiring the plane as some are suggesting.

I would do my best to bundle it up the best you can, as that will help with strain relief and help the longevity.

Larry

I agree. Its been flying fine. And, unless you're going to do some big upgrade, its probably best to try and tidy it up with a few zip ties in such a way to provide strain relief on some of the connectors and call it good.

However, 2 points to be made: 1) Unless you understand wire bundling practices, its very possible you could create as many problems as you solve. And 2) if you ever have to do any kind of avionics upgrade, you're gonna have to deal with that rats nest, and sometimes its easier to rip it out and start over.
 
Firstly, no Cessna EVER came new out of the factory with wiring like that. I would suggest if your 1957 C-172 had wiring worse than that then it had avionics upgrades/maintenance along the way performed by incompetent avionics technicians.

Really? No kidding. It got that way over 50+ years of additions and subtractions. No arguments about the technicians. Point is, it always worked, never had a problem and didn't present any dangerous situations in over half a century.

Secondly, bundling wire runs into looms is NOT about looking "pretty". It's all about organisation and safety. Bundling wires gives them superior support, limits unwanted movement, takes stresses off connections, and greatly reduces the possibility of wires chaffing on the airframe.

Organization, I will buy...safety, well, that is a subjective thing in this discussion. As has been posted, there are many, many examples of this kind of wiring that have stood the test of time with no adverse effects to the user. The rest of the statement I have no argument with; all of the examples you list are great examples but history has shown that the rat's nest has not necessarily been dangerous.


To me, dangerous building is about poor workmanship leading to a significantly increased possibility of an adverse outcome. I think that's pretty much what I see in the photo posted by the OP. ;)

Wow, that's a huge generalization. Let's go to Oshkosh and look at the RVs there and grade them all on workmanship. How many would be above your particular subjective bar? Would you consider those below your bar to be of poor workmanships and therefore dangerous? What about those that are ABOVE your bar? Does that make yours look like poor workmanship and therefore dangerous?

Point is, what you may consider flawed and dangerous, might be someone else best effort...and if they at Oshkosh, they ALL passed muster and have an airworthiness certificate...and they were safe enough to FLY in...

As I have said before, I would not consider that rat's nest to MY standards and I would likely start over...but that would be for me only. It is, however, a flying aircraft and the owner likely has HIS own bar to meet...
 
Bundling wires gives them superior support, limits unwanted movement, takes stresses off connections, and greatly reduces the possibility of wires chaffing on the airframe.

To me, dangerous building is about poor workmanship leading to a significantly increased possibility of an adverse outcome. I think that's pretty much what I see in the photo posted by the OP. ;)

I agree, wiring like what the OP posted negates any and all benefits of "strength in numbers" wire bundling. It may not be obviously dangerous but I will bet my next paycheck that you would see more failures with wiring like this than doing it properly. That being said, I'm not going to tell the OP to change his wiring, I have learned it is far too easy to make general statements on how to repair something on this forum if it's not your plane.
 
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OK, back to the Op...
He doesn?t like it. He wants advice.
He wants it to be pretty.
So...
Here we go.
1. Figure out a way to get the greatest access to the ... birdie nest.
This might require to remove other big items to get more vis, light.
Access from below while lying down might work best.
2. Note the wiring connectors and such...are you capable of soldering, crimping,
organizing, routing, electrical stuff.
3. My bet is most of your bird nest is excess wires that need to be routed in a
organize manner. To and from the device to the bus. Or a antenna. Etc.
4. Cell phone? Take pictures first of everything for ref. Then label before
disconnecting.
5. Organizing...fore and aft...left and right...zones...define routes.
Avoid crisscrossing. We are not ready to snip yet. Use twist ties to group.
To consolidate.
6. Now, you might just love all the work you just done and be satisfied not to
snip. Everything bundled, grouped, purty. Nothing burning, things running.
Or, press on to the next ?Oshkosh ? award winning level.

Ain?t experimental liberating? You become the master of your desires. Even if you?re not the ?repairman? ad hoc. You tell your AnP ?I want to make this right!?
He say...?find...knock yourself out. Let me know when your done. I? ll take a look.?
As long as you don?t attract attention by crashing, burning or dying...
everybody is peaches.
When you?re done, take pictures. We ALL want to see...what happened to that cleco or switch or whatever that thang is in the first photo.

R
 
Thanks for all the good information and responses!

I can't answer all the posts, but I can say that the reason this became an issue at this time is due to problems with the radio. I went to remove it to have it bench tested, and I had a very difficult time just navigating the radio out from among all the wires. I also noticed at least two loose wires behind the panel, one black with a connector, and one white with no connector. So, I know I need to at the very least clean this mess up.

My plan for now is to trace each wire, one by one, label them all, and try to route them in something of a neat and logical way. I can then replace what needs replacing and at least know what goes where. I'm expecting it to be tedious and time consuming, but I'm OK with that. I have another airplane I can fly in the mean time. :D

There is no loose cleco in there, so I'm not sure what you guys might be seeing....maybe a stud on a bus?

I did purchase a book on wiring (Aircraft Wiring Guide by Marc Ausman). It is a good book with some good basics. I'll also buy some tools, wire, and connectors to have on hand.

Please give any other advice and guidance that would be helpful. I appreciate it.
 
Helpful guidance:

Go to Ace and get about a thousand little 4-5? long light duty zip ties. they?re great for getting bundles together as you work on them. I find wiring to be soothing, and something that gives a sense of movement to the build. Go out each day and focus on a single circuit and add it to your bundle. use those little zip ties to keep it all together. the next day do another, clipping off the zip ties (light ones break easily which is good in this case), and replacing them as needed. Some form of heat shrink label will finish it off and make it look very professional.
 
Make sure to strain relieve. Wires hanging off connectors, wires vibrating, chaffing on structure can cause failures. Make sure you have service slack, no wires pulled tight. Have fun tracking and tracing wire runs. It's an acquired skill and pleasure.

Also try and start a power distribution system wiring diagram, alternator, battery, starter, relays, ground bus (if you have one), lights, switches, circuit breakers...

To document avionics is advanced and best attempted with the OEM manual. If you cant get into details show at least where the device gets power and circuit protection.

Speaking of protection make sure all power wires have fuse or CB. Keep in mind the protection is for the wire not device. There is a table of wire gage vs length and circuit production. You want fuse/CB to blow before wire smokes.

Of course the wire must be sufficient to provide power to device without getting too hot. Keep in mind bundling wires will make them run hotter.
 
This is the right side (co-pilot side). There are a couple of buses and some sort of circuit board. I have not traced any of the wires yet, just got the panel out and labeled a few wires that I had to disconnect.

EfsjSOkl.jpg
 
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...and the left side. There's another circuit board. That one bundle of wire with zip ties comes from the intercom.

eqrEsX7l.jpg
 
Looks cleaner then mine :D

+1

Clearly, most folks haven't peeked behind the panel of a 40+ year old GA airplane. ;)

A few years back we installed a new radio, GPS, & removed a few outdated items that were inop (think LORAN), and in the process removed 15 lbs of unused wiring and connectors!
 
...and the left side. There's another circuit board. That one bundle of wire with zip ties comes from the intercom.

eqrEsX7l.jpg

That circuit board looks like the dimmer control panel. Some of the wires have been numbered, any reference material come with the plane? It looks worse than it is, you will have it straightened out pretty quickly.
 
True

My 1979 Warrior had a huge mess of wire that wasn't even connected to anything, anywhere -- it was just hanging out back there like a bird's nest.

I also discovered that my alternator had been wired up in a very nonstandard way with the wrong wire, etc. Caused a nasty arcing event that could have been much worse.

+1

Clearly, most folks haven't peeked behind the panel of a 40+ year old GA airplane. ;)

A few years back we installed a new radio, GPS, & removed a few outdated items that were inop (think LORAN), and in the process removed 15 lbs of unused wiring and connectors!
 
Thanks, Scott. Nothing came with the plane with regard to the wiring. Now that I've got it all apart, I'm actually thinking about going with a VFR glass set up if I can do it somewhat reasonably cost wise.
 
I removed the instruments and the panel. Here is what it looks like behind the panel:

HL5jJqOl.jpg

I imagine you have started to figure some of this out. The collection of push on connectors is probably your "forest of tabs" for ground wires. The photo is just fuzzy enough I can't make out the other green circuit board.

Going to glass buys a lot of capability. A nice EMS would be a nice addition, an opportunity to clean up wiring and get some additional engine performance and monitoring capability.

If you have questions along the way there is plenty of help here.

good luck.
 
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