ACK E-04 ELT false triggers when the avionics is turned on.

[K=1/2mv^2]

Has anyone had any problems with their ACK E-04 ELT going off when the avionics is turned on? RV14a getting close to maiden flight, however the ELT unit does not like all our radios being turned on. We disconnected the remote cable and the GPS info cable, leaving the ACK E-04 ELT unit with only the coax, static suppression device, and its antenna connected, yet the ACK E-04 falsely triggers. The coax cable does not run with any other cables and has good integrity with no shorts to ground. Coax does end up going to ground at the antenna mount (by design). The closest antenna is on the bottom side about 4 feet forward of the ACK E-04 ELT. We disconnected the antenna from the coax, unit still false trips. It appears the energy from our radios is getting thru the plastic casing of the ACK E-04 ELT.

We can keep this from happening if we wrap the ACK E-04 ELT in aluminum foil. We are using the heavy-duty Reynolds wrap, aviation grade (2 layers). I would prefer a more professional solution than Reynold’s wrap. We are using the Dynon AFS AF-5600 in a dual EFIS configuration with SKYVIEW SV-COM-X25/H, Skyview SV-ADSB-472, Skyview SV-XPNDR-261, Avidyne IFD-440. We don’t even have to transmit on com to have the ELT false trip, which likely means this is triggering from the ADSB out.

[philb]

I’ve been unable to troubleshoot my three false alarms thus far. Rewired, added suppressor, ran wires alone. Replaced remote and audio batteries.

After third alarm, third main battery, I just turned the **** thing off. Next step is to replace it with something better, although maybe I’ll try your foil technique!

Lots of posts on this issue. Company no help.

Phil
RV10, flying
Salt Lake City

[K=1/2mv^2]

Just knowing others are having similar issues means I am not alone. We have 6 hours of run time with the Reynolds wrap and no false trips with avionics on. I color matched the Reynolds foil to RV14 for a stealthy look.

https://photos.google.com/share/AF1Q...dUY0hZSVlfMUNR

[edclee]

Originally Posted by K=1/2mv^2

Has anyone had any problems with their ACK E-04 ELT going off when the avionics is turned on? RV14a getting close to maiden flight, however the ELT unit does not like all our radios being turned on. We disconnected the remote cable and the GPS info cable, leaving the ACK E-04 ELT unit with only the coax, static suppression device, and its antenna connected, yet the ACK E-04 falsely triggers. The coax cable does not run with any other cables and has good integrity with no shorts to ground. Coax does end up going to ground at the antenna mount (by design). The closest antenna is on the bottom side about 4 feet forward of the ACK E-04 ELT. We disconnected the antenna from the coax, unit still false trips. It appears the energy from our radios is getting thru the plastic casing of the ACK E-04 ELT.

We can keep this from happening if we wrap the ACK E-04 ELT in aluminum foil. We are using the heavy-duty Reynolds wrap, aviation grade (2 layers). I would prefer a more professional solution than Reynold’s wrap. We are using the Dynon AFS AF-5600 in a dual EFIS configuration with SKYVIEW SV-COM-X25/H, Skyview SV-ADSB-472, Skyview SV-XPNDR-261, Avidyne IFD-440. We don’t even have to transmit on com to have the ELT false trip, which likely means this is triggering from the ADSB out.

Yes, I have had a similar problem although I had not proved the avionics caused it. I have had three turn-on events in the last 18 months and had conversations with Scott AFB. I will try the aircraft grade foil...is this an alien interference with out airspace???

[upperdeck]

Add me to the list. The only reason I haven't switched to another brand is because my panel is cut to accommodate this one. Junk.

[fl-mike]

As an avionics designer, it really bothers me that Ack put out a product with ZERO radiated susceptibility testing. If you look at the install manual, there is a big x in that test category. No testing performed. My hunch is they did, and …

Unfortunately, buyers assume these things are well designed and tested because they have a TSO. Nope. I’d like to know how they jammed this through the ACO. Considering this issue affects Cospas-Sarsat readiness, the FAA should have a chat with ACK.

Your problems are almost certainly related to RF susceptibility. I assume you have the “static protector” installed.

Now you get to be the EMI engineer and figure out how to fix this with a bandaid solution.

Shopping by lowest price can be expensive.

There are some good ELT products out there. I worked with some of those guys on the ELT specification update working group.

Oh, BTW, they didn’t test for ESD either, so don’t touch those connector pins.

[smt6]

Search this forum and you'll see plenty of false activations reported. ACKs are junk.

[fixnflyguy]

Mine worked fine for about 6 years, then it started tripping also. It did it more than once, sitting in the hangar with no one around and the plane unpowered. I was tracked down by a hangar neighbor who picked up the signal. I made sure to replace the "10 year" battery in the remote switch, and still had it trip in flight several times. Its now on the shelf and I replaced it with a Kannad 406 AF-Compact. I've heard success with the foil wrap solution, but I'm past that now.

[calpilot]

Sometimes installers use a regular phone cable instead of the supplied cable. A standard phone cable does not have "rolled pairs", the ACK does. If the pairs are not "rolled", it can trigger an activation. If this is the case, get a phone plug crimper and some plugs, cut off the existing end, and install the new end turned 180 degrees. Just a thought.....
DAR Gary

[bdbeatty]

My plane has been flying for 1.5yrs and I also developed false triggers. No changes (other than a brand new paint job) or issues that should have led to it. I changed batteries, checked for corrosion, and confirmed all wiring. No smoking gun. The really irritating part is my audio panel never once alerted me that the elt was triggering. I was safely back in the hangar parked and driving home an hour later when I got a call from S&R. I have basically concluded it was static electricity build-up due to a brand new paint job and the fact I fly in such dry air in winter (Colorado). I will be trying the alien aluminum foil option. Great job ACK. They were zero help btw….”there’s nothing wrong with our unit, not a single one of the hundreds sitting in the back of our shop has ever gone off!” Ok clown, great way to get to the bottom of your faulty product. Also, yes report it to your local FAA station. If they get enough calls they will force ACK to fix their S..t.

As an aside, because of this I have added to my shutdown checklist to tune to 121.5 just before shutting down my avionics. That way I can know for sure if it’s triggering while the plane is on or if is after shutdown.