Effectiveness of ELT

[RVDan]

Today, while climbing out of Cumberland, MD KCBE, I somehow experienced an inadvertent ELT activation (crew fault, it won’t happen again). I was talking to ATC picking up VFR flight following when I heard the ELT in the radio. I quickly checked the ELT switch panel and saw the active light flashing. I immediately reset the ELT and pressed on wondering if anyone observed the ELT. This is a 406 mhz ELT. Within a couple of minutes, my phone rang. I was unable to answer it, but a message was left saying they were the Air Force and were checking on the ELT activation. A minute later, they called my backup contact who was in the airplane with me and left the same message. 15 minutes later ATC told us that they had been contacted about the ELT activation and wanted to confirm everything was ok, which we confirmed all good and that we would be calling the Air Force on landing in KFDK. On landing, I promptly called the number they left and they said they were following me on flight tracking software. They had the lat and long of the activation from the position data that is output to the ELT and could see that I was still moving when the ELT was active.
Now this isn’t the same as a crash, with the antenna buried or broken, but is did prove that the 406 mhz freq is actively being monitored and that they get your precise position in a short transmission, in this case maybe a minute. Further, they followed up with the registered emergency contacts, followed up with ATC and did realize I was still aloft by using a flight tracking app. I am pretty sure that if the ELT were to activate in a crash, and the antenna was intact enough to get the transmission out, someone would be looking for me. By the way, in my memory items for an engine out is “turn on ELT, while still in the air and the antenna isn’t damaged.
This experience confirms that getting the signal out, even for a minute, will get my position to rescuers.
I hope that helps those wondering what good a 406mhz ELT does.

 

[Bavafa]

Glad you are OK and this was a false alarm.

 

[Ralph Inkster]

Yep. Bin there done that.
Back when they first implemented 406 in Canada I had the dubious distinction of being the first to trip the 406 type ELT since their tracking went live. My wife got a call
‘do you know where your husband is?’
Yep, he’s at the airport installing some kind of radio…
When I called search & rescue, they were more interested by the slightly less accuracy of the signal, until I told them we were inside a metal building…

 

[rockyfatcat]

Today, while climbing out of Cumberland, MD KCBE, I somehow experienced an inadvertent ELT activation (crew fault, it won’t happen again). I was talking to ATC picking up VFR flight following when I heard the ELT in the radio. I quickly checked the ELT switch panel and saw the active light flashing. I immediately reset the ELT and pressed on wondering if anyone observed the ELT. This is a 406 mhz ELT. Within a couple of minutes, my phone rang. I was unable to answer it, but a message was left saying they were the Air Force and were checking on the ELT activation. A minute later, they called my backup contact who was in the airplane with me and left the same message. 15 minutes later ATC told us that they had been contacted about the ELT activation and wanted to confirm everything was ok, which we confirmed all good and that we would be calling the Air Force on landing in KFDK. On landing, I promptly called the number they left and they said they were following me on flight tracking software. They had the lat and long of the activation from the position data that is output to the ELT and could see that I was still moving when the ELT was active.
Now this isn’t the same as a crash, with the antenna buried or broken, but is did prove that the 406 mhz freq is actively being monitored and that they get your precise position in a short transmission, in this case maybe a minute. Further, they followed up with the registered emergency contacts, followed up with ATC and did realize I was still aloft by using a flight tracking app. I am pretty sure that if the ELT were to activate in a crash, and the antenna was intact enough to get the transmission out, someone would be looking for me. By the way, in my memory items for an engine out is “turn on ELT, while still in the air and the antenna isn’t damaged.
This experience confirms that getting the signal out, even for a minute, will get my position to rescuers.
I hope that helps those wondering what good a 406mhz ELT does.

This is exactly why the 406 ELT is the bomb. If you are having a really bad day and activate the remote ELT. You can have emergency vehicles rolling before you reach the crash site

 

[graywoodworking]

For those of you who are still building, before you install your ELT (or even take it out of the box), be sure to register the ELT with https://beaconregistration.noaa.gov. That way when you inadvertently set it off, the Airforce knows who to call. Ask me how I know.

 

[Ralph Inkster]

They will cross reference your registration from the 406 programmed Hex code & still know who to call…
My 406 elt wasn’t registered when we accidentally set it off. They called our house within 20 minutes!
We registered it the next day.

 

[scard]

Yep, it works! Even if the 406 is still registered in Canada 10yrs later.... "Canada calling!"
SNAFU doesn't even cover the circumstances .

 

[Snowflake]

This is exactly why the 406 ELT is the bomb. If you are having a really bad day and activate the remote ELT. You can have emergency vehicles rolling before you reach the crash site

Of course, ADS-B now can provide that functionality, and more. 406MHz ELT's were excellent until they were made obsolete.

 

[Tracer 10]

Of course, ADS-B now can provide that functionality, and more. 406MHz ELT's were excellent until they were made obsolete.

Please explain your position more thoroughly. Exactly how does ADS-B broadcast an alert to satellites that then notify SAR of a possible downed aircraft. If I’am on VFR flight following or IFR and equipped with 1090-ES; and in contact with ATC then ATC will know my last position. If I’am VFR and not in contact with ATC & go down in the mountains; then the system will know my last ADS-B hit; although until someone notifies I’am overdue—they won’t be looking for me anytime soon. However If an 406 MHz ELT Signal is picked up by satellite’s; it immediately puts in motion a series of events to determine if it’s an inadvertent activation or an actual crash.

 

[aadamson]

Of course, ADS-B now can provide that functionality, and more. 406MHz ELT's were excellent until they were made obsolete.

Might want to study that further. Ads-b is not and never has been a replacement for an ELT. Without radar coverage, ads-b is pretty useless for location determination. It's the aircraft and it's GPS that sends its position and radar picks that up and pushes it to the cloud. While there is a system that listens for ads-b via satellites, i don't believe it's used for crash detection. E.g. flight MH-370

 

[Amadeus]

If you are having a really bad day and activate the remote ELT. You can have emergency vehicles rolling before you reach the crash site

I wish crash sites were depicted on charts so that we all could just avoid flying in those areas.

 

[Dugaru]

Of course, ADS-B now can provide that functionality, and more. 406MHz ELT's were excellent until they were made obsolete.

Avweb had an interesting video about this issue. The number of ELT “saves” is astonishingly small, while the number of false alarms is depressingly high. Where I fly, I suspect cell phone data and ADS-B will lead the authorities to me if the worst happens. This is why I continue to put up with my $&@! ACK E-04. If I were flying out west or in Alaska, I’d invest in something better. Which still might not survive the crash of course.

 

[BobTurner]

Avweb had an interesting video about this issue. The number of ELT “saves” is astonishingly small, while the number of false alarms is depressingly high. Where I fly, I suspect cell phone data and ADS-B will lead the authorities to me if the worst happens. This is why I continue to put up with my $&@! ACK E-04. If I were flying out west or in Alaska, I’d invest in something better. Which still might not survive the crash of course.

+1. If you want to be really analytical about it, you should look at ‘net saves’ - real saves, minus the number of CAP pilots who die while looking for real or inadvertent ELT signals (it’s not zero). My story: a few years ago, I departed San Diego, vfr, no flight following. As I approached KLVK, I dialed in the tower frequency. But before I could call, I heard the tower calling me! Seems Montgomery field had found a tire on the runway after my departure, assumed it was mine, and followed me on ADSB, notified LVK when it appeared that was my destination. Easily done. Post script: Tower asked if I was declaring an emergency, I said first I’d like a low pass, tower could look with binoculars and see if I was missing a wheel. Tower declared one anyway, began shooing other inbound aircraft away. After the low pass, they reported 3 wheels, I circled back and landed - to be greeted by 12(! I counted them) firetrucks. (I have a theory as to why so many). I asked tower to call Montgomery. Never did hear whose wheel it was.

 

[Dugaru]

you should look at ‘net saves’ - real saves, minus the number of CAP pilots who die while looking for real or inadvertent ELT signals (it’s not zero).

This is an extremely important point. False alarms can be quite costly.

After the low pass, they reported 3 wheels, I circled back and landed - to be greeted by 12(! I counted them) firetrucks. (I have a theory as to why so many)

So what’s the theory?!?!?

 

[BobTurner]

This is an extremely important point. False alarms can be quite costly.

So what’s the theory?!?!?

It was Memorial Day early afternoon. I think all the firetrucks in Livermore, Pleasanton, maybe San Ramon, were already out in a parade somewhere, and they were all bored, so they all came to the airport.

 

[Dugaru]

It was Memorial Day early afternoon. I think all the firetrucks in Livermore, Pleasanton, maybe San Ramon, were already out in a parade somewhere, and they were all bored, so they all came to the airport.

Well I’m glad you disappointed them!!

 

[RVDan]

Certainly ADS-B out data can be used to locate aircraft, but in the US it is a ground based system. There are areas where you loose ground contact 1500 ft or more AGL. Add to that terrain varations and ADS-B data might get the rescuers only within a couple of miles. Since the 406mhz ELT is monitored via satellite, it is likely to be observed when you are down.
In my OP, the ELT activation was at an altitude that was lower than ADS-B out was being observed by a ground station.

If you think the east doesn’t have remote areas, I knew a glider pilot flying the Appalachian ridges, who crashed into trees on a ridge, hung upside down in the harnesses in the tree tops, and was too injured to use his phone. Rescuers could only get an occasional ping of the phone, enough to get them within a couple of miles. Clouds prevented aircraft searches. He was found 2 days later in a very bad way. A 406 mhz ELT may have changed that outcome.

On another line of thought, if you have a Iphone 14 or later you can text via Satcom, assuming you are conscious, have working hands and can find the phone.

 

[Jmilljr24]

Of course, ADS-B now can provide that functionality, and more. 406MHz ELT's were excellent until they were made obsolete.

I'd like to respectfully disagree.


My personal experience:

I had an engine out in a rural area (Northeast U.S.). Before I could check my drawers upon landing (safely) and stepping on to solid ground, the Air Force Rescue Coordination Center (AFRCC) was calling my cell phone (via 406 notification) . With just enough cell service to talk, the caller and I both agreed is was just a "rough landing" and no further assistance was needed. I did make a call in the blind on 121.5 prior to landing and a voice from above heard me and said they would relay to ATC. My position report was vague at best.

As a first responder in my day job, I contacted the local 911 center directly when I found better cell service to make sure no resources were being sent my way as none were needed. They took down a note as they had not received notice yet. I got an updated for the 911 center about 20 minutes later that they received notice from ATC and relayed I was safe on the ground. The location via ADS-B from ATC ( and confirmed later on a flight tracker) was a couple of miles off from my landing location due to signal lose. AFRCC had the closest cross roads and house number to the field I landed in.

I can't say for certain if there would be a difference in the time for the local 911 center to be notified via MY mayday call to ATC or the relay from an automatic ELT notification to AFRCC, but based on my experience AFRCC via 406 was Johnny on the spot. ATC took a bit longer, through no fault of their own. The biggest difference in my option is on the precision of the location. I've had to search for 911 calls in a "3 mile radius" and it can range from minutes to hours for finding a subject. Having a lat/lon giving an accurate stree address is valuable minutes when injuries are involved.

The choice is yours on installing a 406 ELT, but to think ADS-B is a replacement is misguided at best.

 

[aadamson]

I don't think it's a choice. Last I knew it's a part 91 requirement! (ELT is mandatory in the US)

 

[Snowflake]

Currently, you're right, it's not a choice, as ELT's are mandated by law.

And also currently, the ADS-B system isn't set up to work exactly like an ELT system. But... It could be, and we could ditch the ELTs.

ADS-B is monitored globally by the Aireon satellite network, and used for ATC purposes outside the US. Tracking is instantaneous enough that it's good for keeping airplanes from hitting each other, which should be good enough to find a plane on the ground. Track data can point to the crash site, too, further increasing a searcher's situational awareness.

What's missing is A G-switch, although. personally I think it's unnecessary... If you know you're going down, you probably have time to hit an alarm button like the ELT remote switch. If you don't know you're going down, chances are you aren't going to survive it anyway. But one could be devised, and it could interface to the ADS-B transmitter.

 

[Jmilljr24]

I don't think it's a choice. Last I knew it's a part 91 requirement! (ELT is mandatory in the US)

According to this page on the EAA website, ELT's are not required for single seat aircraft. Also I believe having a 121.5 MHz ELT check's the box so 406MHz is not required. So if someone only has a 121.5MHz ELT, I do think it's a smart choice to upgrade to 406.

Interesting tidbit not related to Van's aircraft, the artical also mentions this:

homebuilts other than airplanes (i.e., helicopters, gyroplanes, balloons, gliders, airships, trikes, powered parachutes, etc.) do not require an ELT under this regulation.

 

[clam]

… “Effectiveness of ELT”…
I got a call from the SAR folks one day asking for a situation report. They said they were tracking my 406 beacon, and it was fixed at a location.

I reported this was a mistake because the plane was in a hangar in the paint shop near KAFW.

It seems the painters did not take proper precautions and they activated the ELT.
So I got my plane painted, and the ELT operational check was “thrown in for free”.

Good signal from inside a hangar.

 

[rcarsey]

I have had two activations so far. One was in an RV-6 after I sold it (but before the new owner registered the beacon). Apparently he was working on the plane in a metal hangar and it tripped -- they were still able to get the 406 signal.

The second time was in my RV-12 in flight. Despite the red blinky light being right in front of me, I didn't notice anything. The only clue was that I was hearing ELT-type noises on my local CTAF freq when other aircraft would break squelch. I'm unsure how that was happening, but I found it curious.. but I didn't realize what was going on until my cellphone rang with a Miami area code -- then I looked at the light and hit the reset. I couldn't hear the SAR guy on my phone while in flight.. so I just told him to standby for a few minutes.. after landing we chatted. He was nice enough to tell me exactly what location they had received. I later looked at the G3X logs to see if it registered any sort of G forces around that spot.. but nothing.. and it was a rather calm day too.

Conversely, we've now had 2 121.5 ELTs at my local airport that were tripped by the maintenance shop, and another by a private owner -- the 121.5Mhz kind. Even though our airport is directly under a main arrival path for JFK, its usually at least a day... or two.. before the airport manager gets a call from someone at ATC. Nobody is coming to help you if you have a 121.5 signal. nobody.

406Mhz ELTs are the way to go. Even if you don't interface them with GPS coordinates, the SAR people still get a pretty good location just from doppler. The tech is still being developed -- the latest now is "RL" return link .. where you get an indication from the satellite that your message was received. They're just coming to market now, but at $5,000, it'll be awhile before they get adopted by any GA aircraft.