406 woes

[RobertGary1]

After years of ribbing at annual by my IA I upgraded my ELT to the ECK E-04. Instillation was a pain because I routed new coax because the old was hardwired to the antenna base.  This ELT includes a cockpit speaker and a panel light to tell if you the ELT is activated or there is a fault.

On my second flight with it, coming back from work near SJC I put the plane away in the dark and did not get any indication the ELT was active. On the drive home I got a call from the AF it was going off. When I walked up to the plane I could hear the cockpit speaker from outside the plane. So clearly this happened after I buttoned everything up. The last thing I did was to take some stuff off the tail and put it in my car. That's the only time I can think it could have activated without me hearing the cockpit speaker. 

If that's the case this thing is insanely sensitive. When I mentioned this to my IA he said he always shuts off the 406's when he changes oil because he's had some go off from simple maintenance.

Has anyone else had this issue? This seems crazy. It should be a pretty significant deceleration to trigger it.

-Robert

[kortopates]

'bout time Robert!!  

But no, after what must be at least 3 or 4 years the only false activation I have seen was when I accidentally tripped the panel switch when I was buried under neath the panel and reached up to the top of the panel to help pull myself out. I got that same call within 5 minutes - maybe it was only 3! - and was apologizing to them over the phone for my stupidity. But boy was I happy to see how quickly they are on it should something really happen and I do need help. 

[Igor_U]

Robert,

I have the same unit for a 5y now and no issues whatsoever...

 

 

[RobertGary1]

Also found out that the red light in the cockpit only flashes every 45 seconds when the ELT is going off. Its not on all the time as it was with my AmeriKing 121 ELT. Seems like a bad design. You'd want the red light to be on all the time and in your face.

-Robert

[RobertGary1]

Called ACK. They said it was probably because the cable to the ELT head goes through the rear bulkhead near the power cable. An EMF spike on the power cable when I shut off the master could have caused the activation. Not sure how else you route through the rear bulkhead. Mooney only has the small hole near the battery. I'd rather not make more holes in the bulkhead.

-Robert

[RobertGary1]

Just spoke to an avionics guy on the field here who's been installing avionics for 30 years. He said they have never had one go off bounding over the hanger door rail or working on the plane. Except once, they had one that would go off at random times and it was defective. So he suggested I go out to the airport and bounce the plane around (shake the tail, etc) and see if it sets off. The mount is very secure so I'm not worried its a mounting issue.

-Robert

[kortopates]

i am pretty doubtful about the wire run being too close to a power cable and I would think it doesn't get real close to the master relay near the battery, which I think would be a bigger emitter. If it happens again I'd be wondering if you have a defective unit and whether ACK can bench test it to confirm. The owner seemed very responsive with past inquiries.

[John Mininger]

My Artex 345 406 went off a few weeks ago. Same experience as the rest of you guys. The AF called and asked if I was in distress. I told them no, and that the airplane was in the hangar and had been for the past two weeks. I was only a couple of miles from the airport so I went over and checked. Sure enough, the ELT was going off. The AF said that they couldn't get a position, probably because the plane was in a metal hangar. But they did receive the N-number from the broadcast.

I called Artex and they said that they were pretty sure the problem was in the unit itself. They said that they would send me a new unit. I'm assuming it will arrive either today or tomorrow.

I'll report back if that fixes the problem.

 

[RobertGary1]

Thanks. I'm growing more skeptical about the story of the wire running too close to the battery cable. Part of what makes me question that is that I can hear the cockpit ELT speaker from outside the plane. I can't imaging I spent 15 minutes putting the plane away and didn't hear it. When I drove back to the airport after getting the AF call, I could hear the ELT speaker as soon as I got out of my car. Last thing I did was take some stuff off the tail. I'm thinking the light bounce of removing stuff from the tail did it. So I'm going to try to get out this week and bounce the plane around.

-Robert

[RobertGary1]

Still keeps happening. I finally spoke with the engineer at ACK engineer. I think we've narrowed it down to static in my cover. When I put the cover on the plane if the cover touches the ELT antenna it zaps the board on the ELT. I have a couple other tests to do but if that's the case the only solution is to be very careful not to touch the elt antenna when putting the plane away.

 

-Robert