Water-logged Uavionix Tail Beacon

wslade2 · #1 05-20-23, 01:39 PM

Yup. Every time I think they’re unblocked, they get blocked again. Don’t take them for granted or think just because you did them recently they’re ok.

Joes · #2 05-23-23, 07:40 AM

Moisture:
The port in the unit where the wires come out is a pitot-static opening for the onboard Baro. This open port will always allow SOME moisture in the unit if you are operating in a humid area, and the electronics are covered with a conformal coating to protect against this. Obviously, the conformal coating on your tailBeacon failed to protect the circuitry. I did notice that there was visible water marks on the outside of the tailBeacon. This indicates that there is likely a large amount of water being directed at the portion of the tailBeacon that is inserted inside of the aircraft.

Some aircraft, merely by their design, channel water to the tailBeacon installation location and can cause more water onboarding than normal. To help combat this, we have seen some customers place a piece of fuel-tubing over the aluminum nipple where the wires exit the tailBeacon. Safety wire the fuel tubing to the nipple, and allow the tailBeacon wires to travel through the fuel tubing, but do NOT close off the air-supply through that open aluminum nipple. The fuel tubing can be looped or re-directed in a fashion that will help prevent water from traveling along the wires and into the tailBeacon.

You will never be able to eliminate humidity condensation, but your installation method can help prevent water channeling into the unit.

This is from Uavionix for installation of a replacement due to moisture in initial unit. Joe

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Name: uavionix.png
Views: 9912
Size: 104.9 KB

mshac · #3 05-23-23, 02:23 PM

uAvionix opened an RMA for me and had me return the unit to them. I'll update here what happens and what the costs are, if any.

Regarding the above post, they sent me the same email with the same photo and wording. Not sure if the tube would've helped or not, but I'll do that upon reinstallation. Certainly can't hurt!

And I'll start checking drain holes more frequently.

Joes · #4 05-25-23, 06:44 AM

It is my understanding the moisture issues with the Uavionix tail beacon, is from water trailing down the wires into the unit. With a hole placed in the bottom of the tube loop and oriented downward, this should help the problem. As for the unit being submerged, that will call for other measures lol. Uavionix was great to work with and replaced my unit with a new one for 1/2 AMU. Joe

mshac · #5 05-25-23, 08:59 AM

Quote:

Originally Posted by Joes

It is my understanding the moisture issues with the Uavionix tail beacon, is from water trailing down the wires into the unit. With a hole placed in the bottom of the tube loop and oriented downward, this should help the problem. As for the unit being submerged, that will call for other measures lol. Uavionix was great to work with and replaced my unit with a new one for 1/2 AMU. Joe

The water doesn't exactly "trail down the wires" into the Tailbeacon. It simply enters the tailbeacon through the same hole that the wires go through. The hole is intentionally not sealed so the the baro sensor can get a reading.

That clear tube around the wires in the picture is not included in the install kit or mentioned in the instructions (at least wasn't when mine was installed). That is uAvionix's "suggestion" as to how one might keep this from happening again. In theory it could work, but if the lower rudder cap is 100% full of water like mine was, I'm not sure it would've made any difference.

Joes · #6 05-25-23, 09:21 AM

I get it, the trailing of the water concept was from a conversation with Uavionix tech support. My personal concept on this was to use the tubing with a tee at midway length and silicone applied where the wires come in to the tube. Place a tube on the tee with a down turn at the top. Hope this helps, wasn't happy to have to replace after 2 years. Joe

mshac · #7 05-27-23, 04:35 PM

Quote:

Originally Posted by Joes

I get it, the trailing of the water concept was from a conversation with Uavionix tech support. My personal concept on this was to use the tubing with a tee at midway length and silicone applied where the wires come in to the tube. Place a tube on the tee with a down turn at the top. Hope this helps, wasn't happy to have to replace after 2 years. Joe

That sounds like the best we can do for now!

I like the thinking.

If we keep our rudder cap drains unclogged it will never be an issue.