GPS locator device

I am admittedly technically challenged but was thinking why a GPS system couldn't be used to locate a down or missing aircraft.

Onstar in my Tahoe knows precisely where I am all the time. It knows my mileage, tire pressure and if i have hit anything recently.

I believe the vast majority of us fly with a GPS providing situational awareness. GPS recieves it's signal but evidently is only a passive reciever.

Any thoughts on integrating a OnStar type system into our aviation GPS units?

I believe OnStar sends your info out over a cellular modem connection. The closest thing I've seen to what you're looking for is probably the APRS trackers people have been working with. These don't allow 2-way communication though...

Check out findmespot.com

http://www.findmespot.com/

Just bought a SPOT (thanks to DR) works great.

Check out the APRS section.

Lionclaw said:

I believe OnStar sends your info out over a cellular modem connection. The closest thing I've seen to what you're looking for is probably the APRS trackers people have been working with. These don't allow 2-way communication though...

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Actually you can do a bidirectional APRS signal but for emergency purposes all you need is a this is where I am kind of signal or at least this is where I last was. The only thing missing is an auto trigger of it switching from normal transmit location mode to emergency mode. Wonder if an accelerometer rigged to make the switch when a certain threshold is reached i.e. either trigger on impact, like an ELT and/or in case a certain decent speed is passed. Dunno it is definitely worth researching.

You can read a ton about the APRS rigs in the APRS section of VAF.
http://www.vansairforce.com/community/forumdisplay.php?f=104

steveKs. said:

I believe the vast majority of us fly with a GPS providing situational awareness. GPS recieves it's signal but evidently is only a passive reciever.

Any thoughts on integrating a OnStar type system into our aviation GPS units?

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Many of the 406 MHz ELT units that are out have this feature in them. All 406 MHz ELTs are already registered for the specific aircraft, so as soon as the signal is received, the monitoring facility knows the details on the aircraft (N number, owner's name and contact phone number, etc...)

Several of these units will receive the datastream from the GPS and include the last lat/long in the databurst as well.

Granted, units that can do this start at $2,000-$3,000. They are out there. Hopefully the price will just come down to a more reasonable level soon.

Steve

PLB's

The latest generation PLB's also have a built in GPS that will send your ID and location to the satellites when activated. These cost considerably less than the ELT versions ($500-$600 versus thousands). Yes, you have to manually activate them.

Paul

Paul, the problem with activating the PLB is that it activates SAR. Great if you are in trouble but systems such as findmespot can provide your location without calling out the calvary.

As far as APRS, I am not familiar with it but does it rely upon ground antennae? If so, it may not have coverage where I fly often (Rockies).

Thanks for the responses.
The Spot system and/or Spider Tracks type system incorportated into a Aviation GPS.. maybe with the tracking feature added on to a XM subscription.

Likely in a day or two, gps recievers will carry a tracking chip of some kind. Probably in the next Garmin x96.

Ron Lee said:

As far as APRS, I am not familiar with it but does it rely upon ground antennae? If so, it may not have coverage where I fly often (Rockies).

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Ron, time to get up to speed on APRS. Go to the "APRS Tracking" forum, read the stickys and associated posts. The technology is too inexpensive and potential helpful not to have in your plane.

Yes, you fly in the Rockies, but there are APRS digipeaters on them thar high hills. Here is a map of the digipeaters in Colorado:

http://wa8lmf.net/APRSmaps/NorthAmericaLarge.htm

Coverage looks like it should be pretty good especially for someone such as you who likes to fly high.

Ron Lee said:

Paul, the problem with activating the PLB is that it activates SAR. Great if you are in trouble but systems such as findmespot can provide your location without calling out the calvary.

As far as APRS, I am not familiar with it but does it rely upon ground antennae? If so, it may not have coverage where I fly often (Rockies).

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I don't see that as a "problem" Lee, as the original poster was asking about a "downed or missing aircraft". In that case, I think I'd like to have SAR activated!

Of course, for curiosity tracking, there are a bunch of new options showing up!

Paul

Sam, after I made my first post I did google APRS and found a map similar to the one you provided. I also read that the typical coverage around them is 30 miles. So if my assessment is correct, I don't have total coverage even at my cruising altitudes and it gets even worse closer to the ground. Am I wrong?

Paul, people should know that even ELTs do not come close to 100% activation in accidents. Most recent example occurred with an RV-10 near Austin, Tx according to reports.

Thus, my view is that if you have a track of an aircraft until it lands/crashes, that is far better than relying upon an ELT or new system that is activated by a crash.

My conclusion is that of the systems I have read about...the findmespot system may offer the best solution. Use the "Track Progress" function on every flight and not only can your friends track you but if you go down the search element of SAR should be a non-issue.

I do not own a findmespot system nor do I have any stock in it to my knowledge. Actually, I was considering buying one this week but since it uses Globalstar...and I am not sure of the financial solvency of that company....I am waiting.

Ron Lee said:

Sam, after I made my first post I did google APRS and found a map similar to the one you provided. I also read that the typical coverage around them is 30 miles. So if my assessment is correct, I don't have total coverage even at my cruising altitudes and it gets even worse closer to the ground. Am I wrong?

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Ron, a reading of the posts in the "APRS Tracking" forum will describe how we are routinely hitting repeaters from over 200 miles. I hit one the other day 225 miles away and I was 1500' AGL. This was with a 300mw transmitter and eight watts is available easily.

Your "mileage" will no doubt vary in the Rockies and I can't predict what kind of coverage you will get. But APRS operates on line-of-sight, and if you are high you might hit a repeater a loooong ways off if the repeater is on a mountain. Obviously your coverage would suffer if you descend into a deep valley far from a repeater.

APRS is not a final solution, just one more option. Read our forum and let me know what you think.

The 30 mile range is typical of their ground coverage, based on you in your car with its antenna 4-5 ft off the ground. The higher you are the longer the distance.