Wing Root Connections

[rmcgann]

For those who are using wiring connectors at the wing root, what is your preferred method? Connector permanently fixed on the fuse or wing side, or both left 'floating'? Junction Box inside the fuse, with a wiring pass-through in the skin? How have you connected shieded wires (eg strobe shields) and have you grounded them locally at the connection? Have you earthed the BNC connectors at the join? How have you separated noisy lines (eg strobes/landing lights) from RF and/or data signals (eg Nav antenna and autopilot). Separate connectors for DC (lights, fuel sender, stall warning etc) and digital (eg autopilot)?

all feedback appreciated.
cheers,
Ron
RV-10 finishing

[Scott Will]

Per the local RVers, mine are free floating. I have three basic types of connections...

one is a 6 circuit molex with the strobes, nav and landig lights
one is a female/male BNC for the antenna
one is a 9 pin circular AMP connector for the autopilot (right wing only)
and last but not least, a connector for the pitot line (from SafeAir1)

made my wires extend about 1 ft from the fuse and wing so you can pull them up to work on them.

[Highflight]

I guess that I'm still unclear about why you would want to have connections there.
RV's aren't ultralights with folding wings, nor are they designed to be frequently disassembled. I don't know so maybe someone can tell me here; do an of the single engine Cessnas, Pipers, etc. etc. have connections there?

It just seems to me that it's just one more place for eventual corrosion and problems to surface without the need for allowing such.

[Jekyll]

I used a 7 wire terminal board screwed to the inside of the fuse under the seat. The strobes are connected by a terminal for each wire and 1 for the shield. That leaves 1 coax for a wing tip antenna which I have a bulkhead connector for.

Why have wing connections? The wings will come off someday and I don't want to crawl under the panel to disconnect wires and break open wire bundles. The older I get, the less flexible I become. I also don't want to remove wires from the conduits to remove a wing. It can be difficult to get the wires back in and the connectors/terminals will need to be removed for removal.

Lastly, I want to do all the building at home before assembly at the airport. wiring disconnects greatly aids that effort.

I'm not thinking the terminal blocks will measurable reduce the reliability of my systems.

Jekyll

[f1rocket]

I used a bulkhead connection for my antenna wire and an AMP bulkhead connector (12 pin) for all the others. I connected the grounds as if they were a separate wire, particularly the stobe, to avoid ground-loop induced noise in the airframe.

The reason I did this was two-fold. One, I anticipated removing my wings after flying in order to paint. Two, I like to get as much done in my garage at home before hauling everything to the hangar and working over at the airport (less convenient). So, I install one wing at a time, wired up the connectors, tested the circuits, and then removed and stored the wings for final assembly.

I agree that it can be an additional failute point. However to reduce that risk, I use gold plated connectors assembled with high quality crimpers, and I test each connector for quality before I'm done. I also inspect them during the condition inspection. But I agree it's not for everybody.

[Scott Will]

Good points Randy.

I agree its not for everybody. Closely examine the failure types and what impact it will happen if you lose some or all of the connections. Then base your decision on that.

Taxi/landing lights... no show stopper (depending on runways you plan to use)
Nav/strobes... again no show stopper
Autopilot... you be the judge.
Heated pitot, if installed... may be biggest concern
Antennas... depends on your setup, I guess - my nav and 2 GPS antennas are on the fuselage (I do have VOR and marker beacon in the wings, though ... so you might lose ILS)

In any case, the plane will still fly. If you are strictly day VFR type of person, the concerns of a bad connection are diminished.

[N941WR]

I bought my connectors from Hobby Town and they seem to work great. They are battery connectors for RC models and lock together.

When installing them, a male plug was used for the landing light at the fuselage and a female plug for the position light. That way I can't cross connect them. They are also color coded with color eletrical tape. Again, in an effort to keep me from miss-connecting them.

[Ironflight]

i used standard Molex connectors for lighting and pitot heat, and BNC in-lines for antennas. I agree that once the airplane is assembled, there will be very few reasons to ever take the wings off....I went with connectors for reasons cited above - I wanted to be able to have everything working before it left the garage, and since I couldn't put the wings on there, i actually had extension "test" cables that ran from the fuselage to the wings in their racks. Rather than just temporarily twist wires together, I put in connectors.

Either way is "right" in my opinion....

Paul

[Rick S.]

Ron,

I used Molex on the power stuff, BNC for the antennas and sub D's for the autopilot plus a AN-4 bulkhead for the pitot air, Same reasons as everyone else, stays in garage longer, wings can come off easier. I Plan to cover the entire plug and wires with heatshrink and adel clamp it to either the rib or the fuselage side. Make sure you leave enough of a service loop in case you have to replace any of the connectors. The heatshrink I have is from Raychem, it's leftover from my USAF days, it's 1.5" in diameter but shrinks down really small to completely seal the plug and wires from the enviroment. If I was really worried about moisture getting in I could dab a spot of proseal on each end of the heatshrink. Just my way of going about it, I'm sure there are many other ways and arguments for one way or the other. I do like the terminal block method mentioned in a previous post, that would keep your connection inside the airframe at least.