Can ADS-B provide position information for Search and Rescue?

Wondering if ADS-B equipped aircraft have any advantage should they need search and rescue, given that they broadcast their ID and coordinates. Is positional information logged by the ground stations, and retained for any period of time, or is it "real-time" only? If retained, it seems that ADS-B could supply search and rescue with a last known fix and trajectory if needed.

Of course, used in a glider, this might create some consternation if an ADS-B breadcrumb trail shows a glider making an off-airport landing....

Debating whether to add the new Trig TN72 GPS unit and TA70 antenna to the Trig TT22 transponder in my Experimental glider, for a legal TSO-C199 "TABS" ADS-B system. Can't quite get a handle on the value of ADS-B out vis-a-vis traffic avoidance, versus simply using the Mode S transponder as is. However, if ADS-B out could provide useful tracking in the event of an emergency, that added value would be significant.

Google first, post second. From the FAA website:

The highly precise GPS-based surveillance provided by ADS-B also improves the ability to perform life-saving search and rescue missions. Air traffic controllers tracking aircraft with ADS-B Out have more accurate information about last reported positions, helping to take the "search" out of search and rescue. ADS-B Out avionics transmit data approximately once every second, and therefore enables more precise tracking of aircraft compared with the current radar sweep rates of 3-15 seconds. The smaller footprint of ADS-B ground radios enables their placement in areas where a radar site would be unfeasible, such as mountainous terrain. Air traffic controllers have better information about an airplane's last position, thereby reducing the critical window of time involved in a search and rescue operation.

Surprised that more is not being made of this.

On Tuesday, February 14, 2017 at 7:30:57 PM UTC-8, Paul Villinski wrote:

Debating whether to add the new Trig TN72 GPS unit and TA70 antenna to the Trig TT22 transponder in my Experimental glider, for a legal TSO-C199 "TABS" ADS-B system.



If you already have a Trig 22 in your experimental glider, you can legally connect one of the existing GPSs you probably already have in your panel to your Trig, and start sending adsb-out as a NPE aircraft. This is explained in the FAA document

https://www.faa.gov/nextgen/programs...3-15-webV2.pdf

As explained in the FAA document, ATC may choose to not send your adsb-reported position to other aircraft. But they will receive your transmission, so presumably could use it for search-and-rescue purposes.

If you do this, you need to use the Trig setup menu to select 'uncertified gps' as the adsb source. See the Trig manual.

On Tuesday, February 14, 2017 at 11:30:18 PM UTC-5, wrote:
On Tuesday, February 14, 2017 at 7:30:57 PM UTC-8, Paul Villinski wrote:

Debating whether to add the new Trig TN72 GPS unit and TA70 antenna to the Trig TT22 transponder in my Experimental glider, for a legal TSO-C199 "TABS" ADS-B system.



If you already have a Trig 22 in your experimental glider, you can legally connect one of the existing GPSs you probably already have in your panel to your Trig, and start sending adsb-out as a NPE aircraft. This is explained in the FAA document

https://www.faa.gov/nextgen/programs...3-15-webV2.pdf

As explained in the FAA document, ATC may choose to not send your adsb-reported position to other aircraft. But they will receive your transmission, so presumably could use it for search-and-rescue purposes.

If you do this, you need to use the Trig setup menu to select 'uncertified gps' as the adsb source. See the Trig manual.

If you already have a Trig transponder, I would spend the extra money to add a TN72 GPS source and not just use an uncertified gps. Using the TN72 will trigger ADS-B ground stations to send you traffic data. For $200 you can get a FlightBox (https://www.openflightsolutions.com/flightbox/) dual frequency ADS-B receiver. Add your iPhone and the free FltPlan Go app, and you have a complete ADS-B collision avoidance system, plus free weather, TFRs, etc.....

You'll be amazed at how much traffic is out there that you never see visually.

I believe it's worthwhile for an experimental glider to transmit adsb-out, even if only using an uncertified gps, because it will make your glider show up more accurately on Flarm receivers even if you don't carry flarm yourself (adsb-out targets show up on flarm with exact location and altitude). You should also show up for equipped power aircraft even if out of ATC radar contact.

The main reason to pay for a certified gps to send adsb-out would be if you also plan to install adsb-in and a traffic display. I still don't see a low-cost low-power adsb-in system for a glider, although I'm sure they will come. The FlightBox adsb-in device appears to draw 1.3A at 5V, ie probably 0..7A at 12V, which would be too much for my glider battery. Also, I would want a sunlight-readable display (I don't find iphones etc to be sunlight readable).

I don't plan to install flarm in my glider, because I think transponder+adsb will soon be the better choice.

The Air Avionics TRX products look like they will be filling the gap to provide ADS-B in capability for traffic in a glider friendly way. They also have models with FLARM TX and RX so you can have both if you want. I agree with your premise entirely that a transponder with ADS-B out is the proper way to go. FLARM is just a stopgap, and not a particularly good one at that. We need to participate in the airspace system as peers with everyone else if we want to expect to be treated as peers.

On Friday, February 17, 2017 at 8:41:59 AM UTC-8, wrote:
The Air Avionics TRX products look like they will be filling the gap to provide ADS-B in capability for traffic in a glider friendly way. They also have models with FLARM TX and RX so you can have both if you want. I agree with your premise entirely that a transponder with ADS-B out is the proper way to go. FLARM is just a stopgap, and not a particularly good one at that. We need to participate in the airspace system as peers with everyone else if we want to expect to be treated as peers.

The TRX product is essentially what is built into every PowerFLARM in the USA.

So can you explain what gap exists and how the TRX fills it?

"ADS-B out is the proper way to go." Proper for what? Proper for avoiding other gliders in busy glider locations, no, absolutely not. Proper in busy airspace with airliners, fast jets, GA traffic, sure. But the critical starting point there is *transponder*, especially vs. airliner and fast jet traffic. If that'a a concern get a transponder in the glider ASAP. ADS-B is secondary and can be worried about later.

On Friday, February 17, 2017 at 8:19:58 AM UTC-8, wrote:
I believe it's worthwhile for an experimental glider to transmit adsb-out, even if only using an uncertified gps, because it will make your glider show up more accurately on Flarm receivers even if you don't carry flarm yourself (adsb-out targets show up on flarm with exact location and altitude). You should also show up for equipped power aircraft even if out of ATC radar contact.

The main reason to pay for a certified gps to send adsb-out would be if you also plan to install adsb-in and a traffic display. I still don't see a low-cost low-power adsb-in system for a glider, although I'm sure they will come. The FlightBox adsb-in device appears to draw 1.3A at 5V, ie probably 0.7A at 12V, which would be too much for my glider battery. Also, I would want a sunlight-readable display (I don't find iphones etc to be sunlight readable).

I don't plan to install flarm in my glider, because I think transponder+adsb will soon be the better choice.

Better choice? For what? You not planning to fly much with other gliders?

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One wrinkle to be aware of is certified ADS-B In systems will *not* see your traffic at all if it is using a non-certified/non-compliant ADS-B source. They are as anal-retentive as the FAA ADS-B ground infrastructure (or rather last year the FAA made the ground infrastructure deliberately as anal-retentive as the airborne certified ADS-B In systems to discourage use of non-compliant GPS sources partially to help force better compatibility with those certified airborne ADS-B In systems).

So folks who have an experimental glider sure they can hook up any old GPS source say to a Trig transponder, and it will show up on PowerFLARM and non-certified ADS-B In systems. But really not a good idea, probably not a good idea to talk about without being clear on the limitations, especially now there is a Trig TN72 GPS is suitable for use in experimental gliders and does not have those limitations (Lots of discussion on the TN72 on other threads on r.a.s.). But if folks have an experiential glider with a Trig transponder and want ADS-B Out the TN72 is really now likely the minimum they should be thinking of.

Trig says the TN72 ($359) and TA70 antenna ($345) will start shipping second quarter of this year. Because I usually fly in busy airspace near New York City, and I rarely fly competitions or with a dozen other gliders, I'm leaning toward this rather than Powerflarm.

My partners and I have just installed an ADS-B out system in our Grumman Cheetah -- a Garmin GTX 335 transponder with associated WAAS antenna. For ADS-B in we are experimenting with an SDR (software defined radio) USB dongle connected to an 8" android tablet running the free Avare app. Avare requires the addition of a second app, Avare ADS-B Pro, which tunes the SDR allowing you to toggle between 1090 and 978 and has a hefty $2.99 price tag. The SDR dongle with included antenna set us back $15. That's the total cost. It appears to work remarkably well.

It seems like this simple, ridiculously affordable system could work well in a glider using a smaller tablet or phone for a display. However, I don't relish the idea of another screen in the cockpit in addition to my Oudie. I wrote to Naviter to see if they would contemplate software for the Oudie that would allow it to display TIS-B and FIS-B, but haven't heard back....

Are there currently any glider flight computer programs that will display TIS-B?

Any further information on using "not certified, but meets the
standards" so that I can install a TN72 and TA70 in my Stemme?

On 2/17/2017 9:44 PM, Paul Villinski wrote:
Trig says the TN72 ($359) and TA70 antenna ($345) will start shipping second quarter of this year. Because I usually fly in busy airspace near New York City, and I rarely fly competitions or with a dozen other gliders, I'm leaning toward this rather than Powerflarm.

My partners and I have just installed an ADS-B out system in our Grumman Cheetah -- a Garmin GTX 335 transponder with associated WAAS antenna. For ADS-B in we are experimenting with an SDR (software defined radio) USB dongle connected to an 8" android tablet running the free Avare app. Avare requires the addition of a second app, Avare ADS-B Pro, which tunes the SDR allowing you to toggle between 1090 and 978 and has a hefty $2.99 price tag. The SDR dongle with included antenna set us back $15. That's the total cost. It appears to work remarkably well.

It seems like this simple, ridiculously affordable system could work well in a glider using a smaller tablet or phone for a display. However, I don't relish the idea of another screen in the cockpit in addition to my Oudie. I wrote to Naviter to see if they would contemplate software for the Oudie that would allow it to display TIS-B and FIS-B, but haven't heard back....

Are there currently any glider flight computer programs that will display TIS-B?

--
Dan, 5J