The Latest in Emergency Location Devices

[John DeRosa]

My first Emergency Location Device (ELD) back in the early 2000's was an Emergency Locator Transmitter (ELT).  Its only function was to transmit a homing signal on 121.5.  Current modern ELTs broadcast a 406 Mhz signal to satellites with encoded GPS location as well as a 121.5 Mhz homing signal.   There is no service plan required to use a ELT.

After the ELT I purchased a series of Personal Locator Beacons (PLB) which over time got small and smaller.  It too broadcasts a 406 Mhz signal to satellites with your encoded GPS location  as well as a 121.5 Mhz homing signal.  There is no service plan required to use it. The downside is it is a one way outbound communications path.

Then I decided to purchase a Garmin InReach Mini followed by the Mini 2.  I'm thinking of trading up to a Mini 3.  Truly a very nice sized portable emergency location device. It broadcasts on 1.6 Ghz to overhead satellites but has no 121.5 homing signal.  This requires a service plan for use.

Full Disclosure - I haven't tried any of the cell phone base satellite communication systems.  Have you?  How well did they work?

HOWEVER, the latest news on the ever forward progress to make emergency location devices as small as possible was announce this month (April 2026) when Garmin integrating their InReach technology into a WATCH!  WOW! 

For more information click here. 

- John (OHM)

http://aviation.derosaweb.net/presentations

[Peter N. Steinmetz]

I have carried a 406 MHz PLB for over a decade now. I have tried the inReach but it did not seem like the locations were very accurate in the mountains. 

My understanding is the systems used by the inReach are not quite as failsafe as the 406 MHz PLBs. But I would be curious to see any more detailed data on this. 

Peter

[Jeff Stetson]

The old 121.5 ELT's are essentially useless. Authorities now no longer respond to them at all, unless there is other evidence of a crash indicating that it's real. These old units are "legal" if already installed, but cannot be resold, reused in another aircraft or repaired legally. The 406 ELT;s are much better but still have a high failure rate. No ELT is required for gliders in the USA.

PLB's are, relatively speaking, great, but most don't trigger automatically. They stay with you, not the plane. They are not to be used if you can contact responders by other means, cell phone, for example.

One personal experience with crash detection available on some phones: Before any club members arrived, a Light Sport flipped over after an early morning landing at our quite rural gliderport ~3 years ago. Rescuers from the local volunteer fire department were on the scene within minutes, called automatically by the guy's iPhone, most likely via the mobile network. The newer Android phones, like my Pixel 10, also have this feature. It must be enabled by the user to be active. Some also can use a satellite connection if the network isn't available.

[Mark Mocho]

One advantage of the Garmin InReach equipment and service is the optional benefit of a dedicated Search and Rescue insurance plan. For $29.95 per year, costs of Search and Rescue are covered, as well as accidental death and dismemberment, some medical and some liability. If you go down in a remote area and need dedicated Search and Rescue services, you don't get hit with associated SAR expenses. This includes helicopter rescue, for example. SAR sometimes can cost you thousands of dollars. Read the policy on the InReach website.

  "Search and Rescue means those reasonable costs incurred for fuel, operating costs, repair and rental of: • motor vehicles; • aircraft or helicopters; • hovercraft; • Unmanned Aerial Systems when operated according to FAA guidelines and regulations; • snowmobiles; ......."

(Partial quote from the SAR Policy)

[Eric Greenwell]

I'm very curious about your accuracy issues, as I always thought GPS units all had similar accuracy - within 50 feet or so, anyway. Which inReach were you using? Do you mean the locations were not very accurate while flying in the mountains with inReach? Or was it when hiking in the mountains? And what did you use to determine the correct locations, and how much error did you notice?

[Peter N. Steinmetz]

this was probably 5 years ago. I was hiking in the Tetons and had the breadcrumbs on and the device set so my wife could see where I was. 

It actually had me being at one point in a completely different canyon and another time about 1 mile up a trail in a canyon instead on the mountainside along it. 

It was very strange and I decided it just was not worth the subscription. Sorry that is not a more precise sort of measurement but I just lost interest after seeing that. 

Peter

[Mark Mocho]

Peter-

Were you referencing the GPS location against a map? What was the publication date on the map? What Earth model was the map modeled from? Was the GPS coordinate format set correctly? (DD.DDDD, DD.MM.MMM, DD.MM.SS.S) I am willing to bet that the InReach information was correct, and you were misinterpreting the correlation to the map coordinates. It is also possible that the map was incorrect. I have used GPS as far back as 1994 for hang gliding contests and while "Selective Availability" (a purposeful "skewing" of the position information) sometimes gave a position error of up to a mile and did not agree with published maps, it was much more reliable than your account suggests. "Selective Availability" was discontinued May 2, 2000, by an Executive Order from President Bill Clinton. After that, I had no problems correlating GPS information with maps published within a few years and were using the WGS84 Earth ellipsoid model.

GPS positioning is extremely accurate. The math used is calculated to 17 decimal places. I find it hard to believe that any modern GPS device could exhibit errors of such magnitude unless the map was out of date or egregiously incorrect (possible with older maps or maps from sources other than the USGS.)

If you are interested in GPS and its origins and development, I highly recommend a wonderful documentary available on YouTube about how the original GPS principle was conceived during the flight of Sputnik in 1957, when the position of the satellite was determined by its radio signal. Somebody (watch the video) made the observation that the signal itself could be mathematically reversed to provide the position of the receiver on the ground. And that's how it all started.

The Story of GPS: "The Lonely Halls Meeting" Full Documentary 

[Peter N. Steinmetz]

Mark,

I actually did assume it might have something to do with being in the mountains. Since that was my primary use case for this device, I lost interest in it. 

I think that does overlap a bit with what is being discussed here in this thread, namely, devices to find one in an emergency. A plane crash could be in mountainous terrain, though perhaps the location of the crash is less likely to cause interference than when hiking and climbing. IIRC though, this was a fairly open canyon, one of the bigger ones in the Tetons, though a canyon surrounded by mountains certainly. 

Thus I trust the other PLBs more to function and let people known there is a problem in an emergency and perhaps get an accurate GPS fix out. They don't let you send messages which is a downside for many people. Though it was actually one of the reasons I agreed reluctantly to start carrying one in the first place while climbing as I go into the wilderness to get away from all that sort of thing.

And yes, normally GPS is very accurate. My dislike of them for an emergency locator beacons is not related to that. 

Peter

[Peter N. Steinmetz]

Though thinking about this more, I am now wondering if for glider and airplane use, versus mountaineering use, an inReach or similar device would be a better choice than a pure PLB?

In this use case the deliberate isolation aspects do not apply and the odds of it being in a canyon and unable to provide an accurate fix seem lower.

Does anyone know how well they work in flight? I was meaning to test that.

[Mark Mocho]

It is true that GPS receivers can sometimes be less reliable in steep, mountainous terrain (or even in heavy tree cover) due to their occasional inability to "see" at least four satellites. Three satellite signals will give a position (2D), and a fourth will provide elevation (3D). In open terrain, seven satellites are often in "view." The more satellite signals you get, the more accurate the position. In the "early" days of GPS, there weren't enough operational satellites to provide full coverage over the entire globe. (Or pizza for you Flat Earthers).  As of 24 April 2026, 83 Global Positioning System navigation satellites have been built: 31 are launched and operational, 1 is undergoing commissioning, 7 are in reserve or testing, 41 are retired, and 2 were lost during launch. Receiver technology has matured to the point that even poor reception problems have largely been eliminated. The biggest problem facing us right now are jamming and "spoofing." Here at Moriarty, we occasionally have to deal with loss of service caused by military testing and simulated combat scenarios emanating from the White Sands Missile Range and Holloman Air Force Base. These exercises are scheduled and the dates and times are publicized. You have to pay attention to the schedule, as your flight information and logging can be affected. In one case, we were planning a soaring contest that would have been affected. Our airport Manager, a retired USAF Colonel, was able to negotiate a change in the operating hours of the exercise to permit the contest to be held.

[Moshe Braner]

Moreover, most current GPS receivers listen to signals from other GNSS systems besides the US GPS.  There are European, Russian, and Chinese "constellations" of satellites.  Between that and the improvements in receiver sensitivity, their performance is amazing.  The good ones easily get a fix while indoors, on a seat inside a metal car, etc.

Regarding PLB vs. Inreach etc, the GPS accuracy is NOT an issue for choosing between the systems, since both approaches rely on a GPS receiver in the device to report your position to SAR.  The PLB also offers the possibility of homing on the 406 MHz signal to find you, although that's not as likely to be used.  An important issue is that a PLB has to be manually activated to send anything, and after a crash you may not be able to do that.  An Inreach etc can be set to transmit its position every 10 minutes or so, while flying, and hopefully also after a crash (assuming it is not too damaged, is in an orientation where it can see the sky, etc).  Even if the last transmission is from a few minutes before the crash, it is a lot better than nothing for the purpose of directing the search to the *approximate* location.  Non-satellite communications, such as cell towers (e.g., SeeYou Navigator on your phone) or OGN ground stations (receiving from your FLARM) may yield similar info, unless you are flying in very remote areas.

[*Eric Greenwell1*]

SeeYou Navigator running on an Oudie N with a SIM card will also use the cell towers, but I don't know how useful that would be, compared to it running on a phone. An interesting thought, though.

Eric

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[Ryszard Krolikowski]

I have original InReach for sale.

Like new , $150.

Ryszard

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[Adam Olczyk]

I’ll take it

Sent from my iPhone

On May 3, 2026, at 2:20 AM, Ryszard Krolikowski <ryszard.k...@gmail.com> wrote:



To view this discussion visit https://groups.google.com/d/msgid/rasprime/CALDP%2BBcep3s2_VgHUsMd9nXEKSq_V8NwqVHs6cRLBMkk5PFmEg%40mail.gmail.com.

[Peter N. Steinmetz]

After this discussion I decided to re-activate my inReach Mini 2 and use it on my last long cross country to Minnesota from Phoenix. I must say this worked rather well.

One can send and receive the messages in flight even when no cell service at all. The tracking shows your location to people even where ADS-B does not see you at all (a fair number of spots here out west).

It seems to work best if your correspondents for messaging have the Messenger App as the Messenger to SMS portal is a bit funky.

I will be carrying this during my flight on my person in the future rather than the PLB.

Thanks everyone for the informative discussion. 

Peter 

[Warwick Patterson]

I actually use both a PLB and a “tracker” when flying (both gliding and power flying). 

1) tracker allows others to follow my flight, and in case of a no-show or delay they can look and see where I last “pinged”. I have a Spot and pay for the 2min tracking interval. You can cover a lot of ground in 10 minutes so I want the initial search to be as focused as possible if I go missing. These devices have an “SOS” button, which is routed through a call centre. For example, Spot sos goes to a centre in Texas where they then notify authorities in your area - usually police first unless you have a specific message in your devices’s preferences that says you are an aircraft. In my Spot custom messages I have my aircraft ident and the phone number for the Joint Rescue Coordination Centre in Victoria, BC. Because this takes some time, I also carry…

2) …a PLB on my person - smakpak on my chute in the glider, survival vest in the airplane. This is a registered emergency beacon that is activated by me in an emergency, and the satellite message alerts the emergency response centre directly, which starts the SAR process immediately (in my case, this is in Canada, so the military SAR aircraft are actioned after they do some initial phone calls.). Much like an aircraft ELT. This is a one time purchase with no subscription needed, and lasts several years (5+) before needing battery replacement. 

We had a power aircraft accident recently here. The first notification was from the pilots Apple Watch. It went to emergency responders and his selected contacts. Given the severity of the crash I was surprised the watch survived. 

Lots of options these days, but the more the better in my opinion. 

Warwick

[Warwick Patterson]

I should also mention it’s very handy to set up custom messages if you use a Spot or Inreach. I have one that says “I’m ok but need mechanical assistance”. The other is “Landed safely.” These are mainly used when I’m flying off-airport in the Maule and a stopped “ping” on a river bar or something could cause some concern from my responsible contacts. For gliders a “Successful landout. Need retrieve” message would be a common one!

[Moshe Braner]

A landed-out aircraft has rather limited radio communications range to other radios on the ground.  (Thus the usefulness of satellite communicators.)  How often when one lands out there are other gliders within 10 miles or so in the air?  Messaging those airborne gliders, who could then relay the info to other aircraft or to ground stations, may be helpful.  When I've landed out I've often made contact with airborne glider pilots via the VHF voice radio.

Beyond that, now that FLARM has the ability to send (very short) text messages between FLARM devices, that offers another messaging option.  Alas they charge an extra "license" fee for the capability of receiving user-defined messages.  Also at this time there are not many ways to compose and send such messages or to see received ones.  But that may develop over time.  Currently XCsoar developers, for example, are introducing the handling of the non-custom messages from an attached FLARM, namely the pilot name, contest ID, registration and model, sent by other FLARMs within range (and receivable without an extra "license").  It would be quite feasible to extend that to the custom messages.  But is anybody using those yet?

Note that the FANET system, used mostly by paragliders, includes a similar messaging system.  There are pre-defined "ground status" choices for ground-tracking transmissions, such as "landed OK" or "need med".  And there is a system for broadcast and unicast custom messages.  FANET also includes the capability to automatically relay messages further, and it uses a radio modulation type (LORA) that has a much higher reception range than the modulation (FSK) used by FLARM.

On Tuesday, June 9, 2026 at 1:05:19 PM UTC-4 in...@gogliding.ca wrote:

I should also mention it’s very handy to set up custom messages if you use a Spot or Inreach. I have one that says “I’m ok but need mechanical assistance”. The other is “Landed safely.” These are mainly used when I’m flying off-airport in the Maule and a stopped “ping” on a river bar or something could cause some concern from my responsible contacts. For gliders a “Successful landout. Need retrieve” message would be a common one.

[Mark Mocho]

Switch to 121.5 and contact an airliner. Be sure to have a clear, concise message planned, with your location in a common GPS format (SAR default is generally DDD.dddd) If using DDD.MM.mmm or DDD.MM.SS.s, be sure to specify, as locations can vary 30 miles between formats. Have contact numbers for anyone you want the receiving party to relay. Satellite communication via InReach text or SPOT text is superior to any radio communication, but be sure to keep your subscription active and know how to use it.

[Cliff Hilty]

Way back when there were no plb's or flarm or other emergency devices a visiting pilot doing a diamond badge flight landed out 80 miles from home. Not having a cell phone he used the vhf radio to contact an overflying Southwest airliner on 121.5 (US emergency freq) and had them relay to center that he was down and safe at a local airport. Back at the field we were all back and wondering what we were going to do and of course we concluded we would need to contact ATC and let them know we had a missing pilot. To our surprise they had his location and status and we sent his wife out on the retrieve. Where there is a will there is a way!

Cliff

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[Mark Hawkins]

We had a similar event occur here at Moriarty a few years ago.  Pilot landed about 50+ miles southwest of Moriarty on a decent ranch road about 12 miles from the main road.  Pilot and glider were just fine.  Pilot had cellphone BUT battery was dead. SPOT was blinking away just fine.  Unfortunately, the SPOT's subscription was not active.  But he didn't know that.  He did not hit the SOS button but the lights were flashing on the SPOT so figured the normal periodic transmits were working just fine.   So he made himself comfy in the glider and waited for a retrieve.  And waited, and waited, and waited....

We really started worrying as the sun headed to the western skyline.  We had a general area to look so some folks drove down to the area and searched quite a bit to no avail.  Same with a tow plane but not quite searching in the right area.  So they couldn't find him.  They had a radio but weren't picking up anyone on the radio.  Eventually darkness settled in.  Luckily it wasn't TOO cold.  

The pilot later said that he was sitting in the glider waiting and it was a beautiful night.  TONS of stars overhead and...he could se so MANY airliners flying over head as well.  Oh by the way, pilot IS an airline pilot.  :-)  Eventually, it dawned on him that you know what...he can talk to those airliners...which he did on 121.5.  As with Cliff's event, the airliners passed his location along to ATC.  ATC contacted State Police.  And I believe they then contacted the airport manager at Moriarty to organize a retrieval  After that 3 of us headed down with a very nice Pickup and his trailer to get him.  

This was a relatively long drive including dirt farm roads (nicely maintained) and one or two locked gates.  Luckily the state police motorcycle cop who was meeting us knew the "locals" and had gotten the combinations for the locked gates.  By the time we got there around late morning, the pilot had run out of water a while ago and was getting pretty dehydrated and impaired.  The police officer had arrived a while before we got there and had given him the rest of the small bottle of water he had.  But we put him into the A/C of the truck with lots of water/gatorade.  There were plenty of us to get his glider apart and into the trailer safely.  The state cop even helped out as well which was VERY nice.  Especially since he was in a full black motorcycle suit in FULL New Mexico sun approaching noon.  BZ to him that's for sure!

The rest of the trip back was a slow drive on the farm roads then the country roads but uneventful.  By the time we were headed back the pilot was feeling MUCH better which was VERY good.  Overall, it could have been MUCH worse especially if he had been out in that sun without shade and water for much longer.  

Lessons:

-Make sure your phone is charged and that you have a way of RECHARGING it if you landout.  In this case, there was a cell tower within sight of the outlanding location.  He just couldn't connect to it.  These days many of us using cellphones are able to connect to satellites to send/receive text messages.  But if your phone is dead, that doesn't help much.  :-)

-If you have a SPOT/INREACH device/tracker - Make sure they are working before taking off.  I believe both SPOT and InReach have a "test" mode.  Oh and yes I know its more expensive but PLEASE use tracking mode.  Yes you can push a button in flight to send an update message.  However, if you aren't pushing it very often or if you landout/jump out and are unable to get to the tracker for whatever reason then those trying to find you can only start looking for you wherever you last pushed the button.  That can be VERY far away.  Tracking mode happens automatically and thus creates a "trend" line.  This line of travel and the last position can provide an initial search start point AND direction of search.  It can SIGNIFICANTLY reduce the search area for finding you using this direction of travel and thus reduce the time it takes to find you...ALOT!!!  

Back to the topic of the original post...If FLARM can provide a message transmission capability...BRING IT ON!!!  Same with inReach on a watch.The more avenues to find pilot landout locations can only make retrievals the better!!

-Mark