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False ELT alerts

TShort

Well Known Member
I installed an ACK E-04 during the upgrade on the -10 a couple of years ago.

Since then, I have had 2 separate occasions where the thing has gone off and alerted the CAP.

Before all the comments about crummy landings come in, both events happened 2-3 days after I arrived. The first time the plane was on the ramp at KAEJ and had been there tied down overnight before the ELT went off.

The second was last month, I landed at KLMO and was tied down there for 2-3 days before I got the call that the ELT was active.

Has anyone else had similar issues?

Thanks
Thomas
 
Been there done that

My Ameriking 450 did same thing, but it was in my hangar and friends scanner caught it. I replaced batteries in the unit, and in the remote head. It was fine for a month, then did it again. AVX shop didnt have any good suggestions, so I got a used one to replace it.
 
Yes I had similar problems with mine. I called ACK and they advised it was water in the batteries or RF interference. My batteries were fine. A friend advised me to remove the ELT and wrap it in aluminum foil. Clamp it back in the holder making sure that the wrap was well grounded.

I did this 6 months ago and have not had a false activation since.

Give it a try.
 
I installed the static suppressor after having many false alerts. It did nothing. The ACKs are junk. Buy an Artex
 
False ELT Alerts and Cosmic Rays

When weird unexplained electronic event's like this happened during the F35 development program I was involved in Lockheed would close out the issue by stating it was caused by Cosmic Rays, while I was pretty skeptical as far as I remember the Program Office never complained with this excuse.

So wrong time software reboots, autopilot misbehavior, random ELT activations, messed up GPS approaches, ADSB tracks straying into Restricted airspace, wrong frequencies, the list of things that Cosmic Rays can mess up gets bigger every year as we move into the age of Cosmic Avionics.

If this excuse works for a $25 billion dollar jet fighter program it can work for you too!
 
Error detection and correction

When weird unexplained electronic event's like this happened during the F35 development program I was involved in Lockheed would close out the issue by stating it was caused by Cosmic Rays, while I was pretty skeptical as far as I remember the Program Office never complained with this excuse.

So wrong time software reboots, autopilot misbehavior, random ELT activations, messed up GPS approaches, ADSB tracks straying into Restricted airspace, wrong frequencies, the list of things that Cosmic Rays can mess up gets bigger every year as we move into the age of Cosmic Avionics.

If this excuse works for a $25 billion dollar jet fighter program it can work for you too!
Error detection and correction would hopefully be an important part of those systems. Perhaps they just decided it's cheaper to reboot. :( Seriously, this needs to be a standard part of every HW and SW developer's toolkit.
 
I installed the static suppressor after having many false alerts. It did nothing. The ACKs are junk. Buy an Artex

I'll second this recommendation that the ACK's are a substandard device.

My first recommendation remains the Kannad, despite their expensive battery pack replacement. Their in-service record is at the top of the pack.

The Artex comes next in line.

The ACK E-04 is at the top of my list of "do not install" equipment.
 
It's unfortunate that some equipment providers do not thoroughly test their products.
We buy them assuming that they are well wrung out, but in reality, many test only enough to get the certification, and many TSOs leave environmental test requirements up to the end user to specify or confirm.

It is amusing for me to look at the DO-160 test categories for many certified products that we install on our planes. Many are filled with "X"s indicating that no testing was performed or claimed in those areas. I've see altitude encoders that basically only tested for temperature. Everything else is X's.
Here are the test categories for the ACK E-04.
Notice what I highlighted. No testing for radiated or conducted susceptibility. So, let's say you have a nice high powered ATC surveillance radar on the field that is sweeping your plane every few seconds. You have no evidence that the unit will not respond in a bad way to that. None. (the aluminum foil wrap was not a bad idea!)
Environmental qualification testing is expensive. Figure $100-250k or so for a basic series of tests, if they all pass the first time. (and every time you make a design change, you have to run though an analysis to determine which tests have to be re-run.)

Oh, and I highly doubt these occurrences are due to single-event or multiple-bit upsets (SEU MBU) from cosmic rays. Those affect memory devices (flash mostly) and i doubt the ACK is using a flash based FPGA. Even those typically have mitigation features. (that's another analysis!)

Take a look at the DO-160 environmental qualification test form on the next piece of avionics you are considering. It might be enlightening.
 

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ACK Activation

I had an unintended activation of my ACK Elt two weeks ago and got a call from the air force looking for me on a voicemail at the end of my trip. Somehow the ELT got activated on a dead-smooth flight and one of the best landings I have made. Until I read this thread today, I wondered how it could have gotten turned on...my remote panel for it is somewhat hidden by the bezel of my comm radio and the red LED would not necessarily be in my view while flying. I think the Cosmic Rays set it off :D It has not happened since or previously.
Ed
 
Good Intel on the suppressor

Some good Intel here on the suppressor..hadn't seen that before. I will look at that for my dilemma, as I don't want to keep having false trips, or buy a new one at this point. Just seemed odd I had no problems for 8 years.
 
I installed the static suppressor after having many false alerts. It did nothing. The ACKs are junk. Buy an Artex

My ARTEX had false alerts on different days. Replaced with ACK-E04. Buy ACK, ARTEX are junk :)

My antenna is mounted internally, so the static buildup issue can't occur.
 
I had one FALSE ACK E-04 alarm after a smooth landing during engine shut down.

What upset me was the ACK E-04 FAILED it's 1-year 91.207(d) test and had to be returned to the factory. They replaced the transmitter for FREE but I did purchase a new battery that was NOT needed.

It appears that they may be using a "static sensitive" RF transmitter chip that now requires the static suppressor on the antenna. Now that I am aware that the transmitter can be damaged easily, I will use the ESD training I had at work before I retired when ever I do anything with the ELT.

What worries me more than false ELT alarms is my iPhone has TWICE called 911 without me touching it. Started airplane, went flying, and when I landed, I had a voice message from the 911 operator about 911 call from my number. 2nd time, I started airplane, and when I powered on avionics, the phone was ringing in my headset and 911 operator was at other end. There were several months and many flights between these two occurrences.

My iPhone now goes into airplane mode before I get in the airplane.
 
It must Gary or Gary’s plane causing all this! LOL

You’ll also note that there was no ESD testing claimed the table. Rather disturbing, because that is a very easy and fast test to run...unless you fail.
 
Yes I had similar problems with mine. I called ACK and they advised it was water in the batteries or RF interference. My batteries were fine. A friend advised me to remove the ELT and wrap it in aluminum foil. Clamp it back in the holder making sure that the wrap was well grounded.

I did this 6 months ago and have not had a false activation since.

Give it a try.

As wild as this sounds, I did this...and so far so good. I’ve fought this subpar ELT for four years. Numerous calls from Air Force, Coast Gaurd, ect. If I’d have known all I had to do was wrap it foil...wow
 
I'll second this recommendation that the ACK's are a substandard device.

My first recommendation remains the Kannad, despite their expensive battery pack replacement. Their in-service record is at the top of the pack.

The Artex comes next in line.

The ACK E-04 is at the top of my list of "do not install" equipment.

Totally agree. My ACK didn't pass this year. Only 3 years old. Bought the Kannad after talking to a couple of shops that do the ELT testing. Both said the Kannad fails the least of any. Also has a 10 year warrantee.
 
I have ACK E-04 ELT, in phase one in smooth air in flight it activated, saturated all my comm frequencies. I installed the static suppressor ( Now at 120 hours and have not had 2nd occurrence.)

Keeping my fingers crossed.:cool:
 
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