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

[Paul Villinski]

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.

[Paul Villinski]

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.

[[email protected]]

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/adsb/media/TIS-B_service_change_summary_final_508_5-13-15-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.

[Mike Schumann[_2_]]

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/adsb/media/TIS-B_service_change_summary_final_508_5-13-15-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.

[Sarah[_2_]]

It's not guaranteed you will be 'seen' by a ground station at low altitude, especially out in the boonies or in the mountains. This site supposedly shows coverage by altitude interactively:

https://www.faa.gov/nextgen/programs/adsb/ICM/

Take it with a grain of salt - I saw "0 towers" in central WI last year on the way to Oshkosh at 3000' AGL.

I'm curious what people flying with ADS-B in NV or UT see for ground station coverage.


On Tuesday, February 14, 2017 at 9:30:57 PM UTC-6, Paul Villinski wrote:
> 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.

[Dan Marotta]

That's odd. I saw a different coverage map yesterday that shows pretty
good coverage over the Midwest at 3,000 AGL as well. It would not be
reasonable to think that there were several towers along your route that
were all out of service. I'm fortunate that I can look at the mountain
top out of my living room window and literally see the ADS-B tower
there. From Moriarty airport, I can see the top of the mountain, as well.

The flight box looks to be an implementation of the Stratux system that
you can build for a lot less money from parts bought on Amazon. The
difference being the well-thought out box and configuration. I think
the difference in price is worth it.

On 2/15/2017 8:58 AM, Sarah wrote:
> It's not guaranteed you will be 'seen' by a ground station at low altitude, especially out in the boonies or in the mountains. This site supposedly shows coverage by altitude interactively:
>
> https://www.faa.gov/nextgen/programs/adsb/ICM/
>
> Take it with a grain of salt - I saw "0 towers" in central WI last year on the way to Oshkosh at 3000' AGL.
>
> I'm curious what people flying with ADS-B in NV or UT see for ground station coverage.
>
>
> On Tuesday, February 14, 2017 at 9:30:57 PM UTC-6, Paul Villinski wrote:
>> 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.

--
Dan, 5J

[Mike Schumann[_2_]]

On Wednesday, February 15, 2017 at 10:58:45 AM UTC-5, Sarah wrote:
> It's not guaranteed you will be 'seen' by a ground station at low altitude, especially out in the boonies or in the mountains. This site supposedly shows coverage by altitude interactively:
>
> https://www.faa.gov/nextgen/programs/adsb/ICM/
>
> Take it with a grain of salt - I saw "0 towers" in central WI last year on the way to Oshkosh at 3000' AGL.
>
> I'm curious what people flying with ADS-B in NV or UT see for ground station coverage.
>
>
> On Tuesday, February 14, 2017 at 9:30:57 PM UTC-6, Paul Villinski wrote:
> > 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.

How were you looking for ADS-B towers in WI? When I flew from Chicago to MSP last spring, I had ADS-B ground station coverage with TIS-B for the entire trip. Granted, I was somewhat higher than 3,000 ft. The FAA ADS-B map shows ground station coverage for most of the state at 3,000 ft, which I would suspect is quite accurate.

This summer, I flew from MSP to Bozeman, Reno, Albuquerque, Charlotte, and finally Naples FL. Again I had ADS-B ground station coverage with TIS-B for virtually the entire trip. For much of the trip out west, I was at 14,500 ft MSL. At lower altitudes, I'm quite sure that I would not have had coverage in many of the remote areas. In addition, TIS-B may not be useful, even if you are within range of an ADS-B ground station, if you are at an altitude where transponder equipped aircraft are below radar coverage, and are not visible to ATC.

In 2020, which is only 3 years out, a large majority of aircraft are going to be ADS-B OUT equipped, and as long as you have a dual band ADS-B receiver, you'll be able to see all of that traffic, regardless of altitude throughout the US.

As far as search and rescue goes, don't underestimate the value of amateur run ADS-B receivers that feed traffic data to FlightAware and FlightRadar24.. In many cases the coverage for these receivers is much better than the FAA's network. The GermanWings crash in the Alps a couple of years ago was a great example. FlightRadar24 was able to collect FMS data from their ADS-B receiver network that was available to crash investigators within an hour or two of the crash.

If you fly regularly in a remote area, or are organizing a contest, you can setup your own ADS-B ground station and integrate it into the FlightAware / FlightRadar24 network with a total investment of ~$200 and an internet connection.

[Sarah[_2_]]

>How were you looking for ADS-B towers in WI?

Geeze, Mike. With an ADS-B receiver.

>The FAA ADS-B map shows ground station coverage for most of the state at 3,000 ft, which I would suspect is quite accurate.

I just told you it wasn't.

[[email protected]]

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.

[[email protected]]

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.

[Darryl Ramm]

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.

[Darryl Ramm]

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?

---

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.

[Paul Villinski]

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?

[[email protected]]

>
> 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.


Daryl, maybe I misunderstood....I had read that an adsb target using an uncertified gps would not be considered a 'client' by ATC, but I assumed the location of an uncertified-adsb target would still be included in data broadcast by ATC to client aircraft. I would have thought the transponder alone would have justified inclusion.

Also, would an uncertified-adsb target be detected by a certified-adsb receiver via direct (air-to-air) transmission, and at what approximate range?

Thanks for any help.

[Dan Marotta]

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

[Sarah[_2_]]

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

Assuming you are a fully participating ADSB-out client, TIS-B would be 978Mhz AND 1090es relayed for you. (I think so anyway, in terminal radar environments.)

In that case, either Powerflarm or something like the cheaper $300 TRX-1000 would be able to receive 1090es and feed a common FLARM compatible glider display. Beware though - you would not receive air-air UAT data directly.

If you really need to receive UAT or TIS-B on 978Mhz, you'd need a different receiver. I have read posts on the Stratux ADSB receiver github page about a sw version that emits FLARM formatted strings. This could be connected to LXnav or Oudie, etc. through a USB-to-serial adapter. A bit too experimental for me quite yet.

--Sarah


On Friday, February 17, 2017 at 10:44:40 PM UTC-6, 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?

[Dave Nadler]

On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
> Wondering if ADS-B equipped aircraft have any advantage should they
> need search and rescue, given that they broadcast their ID and coordinates.

1) ADS-B ground stations logging data would need to receive ADS-B down
to near ground level to get close to the crash site. A glider can travel
a long distance from the altitudes mentioned as ground-station receive
floor in this thread.

2) FLARM can assist in SAR (and has done a number of times). This requires
other gliders flying in FLARM-range of the crash, otherwise the search
area will not be narrowed to a helpful size. And the FLARM log files need
to be promptly recovered from gliders in the area and forwarded to FLARM
for analysis.

[Darryl Ramm]

On Saturday, February 18, 2017 at 2:15:12 AM UTC-8, wrote:
> >
> > 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.
>
>
> Daryl, maybe I misunderstood....I had read that an adsb target using an uncertified gps would not be considered a 'client' by ATC, but I assumed the location of an uncertified-adsb target would still be included in data broadcast by ATC to client aircraft. I would have thought the transponder alone would have justified inclusion.
>

A transponder alone will make you a TIS-B target for client aircraft. As long as you are within both SSR and ADS-B ground system coverage. The SSR coverage there is the gotcha, e.g. no coverage at many gliderports and airport pattern areas or say down low on ridges where there might be lots of glider traffic. And TIS-B is so imprecise and has other issues it's of little use compared to Flarm for glider-glider traffic avoidance.

I believe non-compliant GPS (e.g. TSO-C145c or meets performance requirements of, or TSO-C199) will *not* make you a ADS-R target, and even TSO-C199 may not get you on ATC traffic displays (but again if within SSR coverage ATC will see you via that).

> Also, would an uncertified-adsb target be detected by a certified-adsb receiver via direct (air-to-air) transmission, and at what approximate range?

Absolutely not. A *certified* ADS-B In receiver will not display non-complaint ADS-B Out equipped aircraft via ADS-B direct. It will run right into that target with no warning at all. If the aircraft is also equipped with TCAD/PCAS and the target aircraft has a transponder then that system would provide traffic display and TA and (for TCAS-II) RA alerts.

The bottom line is probably just don't mess with non-compliant GPS sources, they will not provide the results that most glider pilots will just expect.. The TN72 (esp. with a Trig transponder) should be the minimum goal to use in experimental gliders today if you want to do ADS-B Out. As folks actually get those systems installed it would be great to hear their experiences and costs. Unfortunately certified gliders currently require installation of a full TSO-C145c certified GPS source, with costs that are non-starters for most owners. I would be nice to see TSO-C199/TABS installation and use regulations that allowed for installation of a TN72 type ADS-B Out GPS sources in certified gliders.

All this mess is part of why PowerFLARM for glider-glider traffic awareness is a popular choice. And its PCAS and 1090ES In helps provide some inbound traffic coverage.

For awareness to other traffic and ATC, especially airliners and fast jets, the humble transponder (Mode-C or Mode-S) is very very effective. In busy traffic areas get a transponder like a Trig TT-22 that you will be able to upgrade to ADS-B Out in future, hopefully as costs fall and regulations improve. In really busy traffic areas please don't put off installing and using a transponder while waiting for ADS-B future toys.

> Thanks for any help.

No problem.

As folks get ADS-B Out stuff installed and working, please share your experiences with others.

[Darryl Ramm]

On Saturday, February 18, 2017 at 9:26:19 AM UTC-8, Sarah wrote:
> > Are there currently any glider flight computer programs that will display TIS-B?
>
> Assuming you are a fully participating ADSB-out client, TIS-B would be 978Mhz AND 1090es relayed for you. (I think so anyway, in terminal radar environments.)

That's not guaranteed. What ADS-B link layer TIS-B is broadcast for a client aircraft on depends on the capability code (CC) data transmitted by the target aircraft. All aircraft with ADS-B Out need to have those CC bits set correctly to match their ADS-B In capabilities.

> In that case, either Powerflarm or something like the cheaper $300 TRX-1000 would be able to receive 1090es and feed a common FLARM compatible glider display. Beware though - you would not receive air-air UAT data directly.

No. Unfortunately this is not correct.

The PowerFLARM does not understand how to process a TIS-B (or ADS-R) message. The European unregulated ADS-B environment that PowerFLARM were developed for is the cause of this limitation. I suspect the TRX-1000 has the same limitation. This is an important limitation that pilots need to be aware of, and why I and others have mentioned in on r.a.s. so many times.

> If you really need to receive UAT or TIS-B on 978Mhz, you'd need a different receiver. I have read posts on the Stratux ADSB receiver github page about a sw version that emits FLARM formatted strings. This could be connected to LXnav or Oudie, etc. through a USB-to-serial adapter. A bit too experimental for me quite yet.

The most flexible/effective ADS-B In traffic system especially for gliders would use dual-link ADS-B In. Much better than relying on ADS-R and all it's limitations. Unfortunately there is no system that does this today and is compatible with typical glider cockpit systems (e.g. supports Flarm serial dataport protocol to transmit traffic data to a display device)

The Stratux for FLARM protocol stuff was really people tinkering with ideas and I don't think it went anywhere.

> --Sarah

[Sarah[_2_]]

> > In that case, either Powerflarm or something like the cheaper $300 TRX-1000 would be able to receive 1090es and feed a common FLARM compatible glider display. Beware though - you would not receive air-air UAT data directly.
>
> No. Unfortunately this is not correct.
>
> The PowerFLARM does not understand how to process a TIS-B (or ADS-R) message.

Ah, too bad. I did not know TIS-B messages are not properly decoded by Powerflarm. PF must then only correctly parse air-air 1090es squawks. Thanks for the clarification.

On a related question, if someone were to connect an uncertified GPS source to a 1090es transponder, with the intention of appearing on others PF displays.... how often would the transponder send this data? Only when interrogated (ie never, out of Radar coverage/TCAS ping range) or often, for each GPS position string? If the latter, this may have power consumption implications.

> The Stratux for FLARM protocol stuff was really people tinkering with ideas and I don't think it went anywhere.

Well it appeared to 'work for them', but I agree... it's too experimental for me yet.


On Saturday, February 18, 2017 at 12:56:10 PM UTC-6, Darryl Ramm wrote:
> On Saturday, February 18, 2017 at 9:26:19 AM UTC-8, Sarah wrote:
> > > Are there currently any glider flight computer programs that will display TIS-B?
> >
> > Assuming you are a fully participating ADSB-out client, TIS-B would be 978Mhz AND 1090es relayed for you. (I think so anyway, in terminal radar environments.)
>
> That's not guaranteed. What ADS-B link layer TIS-B is broadcast for a client aircraft on depends on the capability code (CC) data transmitted by the target aircraft. All aircraft with ADS-B Out need to have those CC bits set correctly to match their ADS-B In capabilities.
>
> > In that case, either Powerflarm or something like the cheaper $300 TRX-1000 would be able to receive 1090es and feed a common FLARM compatible glider display. Beware though - you would not receive air-air UAT data directly.
>
> No. Unfortunately this is not correct.
>
> The PowerFLARM does not understand how to process a TIS-B (or ADS-R) message. The European unregulated ADS-B environment that PowerFLARM were developed for is the cause of this limitation. I suspect the TRX-1000 has the same limitation. This is an important limitation that pilots need to be aware of, and why I and others have mentioned in on r.a.s. so many times.
>
> > If you really need to receive UAT or TIS-B on 978Mhz, you'd need a different receiver. I have read posts on the Stratux ADSB receiver github page about a sw version that emits FLARM formatted strings. This could be connected to LXnav or Oudie, etc. through a USB-to-serial adapter. A bit too experimental for me quite yet.
>
> The most flexible/effective ADS-B In traffic system especially for gliders would use dual-link ADS-B In. Much better than relying on ADS-R and all it's limitations. Unfortunately there is no system that does this today and is compatible with typical glider cockpit systems (e.g. supports Flarm serial dataport protocol to transmit traffic data to a display device)
>
> The Stratux for FLARM protocol stuff was really people tinkering with ideas and I don't think it went anywhere.
>
> > --Sarah

[Darryl Ramm]

On Saturday, February 18, 2017 at 11:13:58 AM UTC-8, Sarah wrote:
> > > In that case, either Powerflarm or something like the cheaper $300 TRX-1000 would be able to receive 1090es and feed a common FLARM compatible glider display. Beware though - you would not receive air-air UAT data directly.
> >
> > No. Unfortunately this is not correct.
> >
> > The PowerFLARM does not understand how to process a TIS-B (or ADS-R) message.
>
> Ah, too bad. I did not know TIS-B messages are not properly decoded by Powerflarm. PF must then only correctly parse air-air 1090es squawks. Thanks for the clarification.
>
> On a related question, if someone were to connect an uncertified GPS source to a 1090es transponder, with the intention of appearing on others PF displays.... how often would the transponder send this data? Only when interrogated (ie never, out of Radar coverage/TCAS ping range) or often, for each GPS position string? If the latter, this may have power consumption implications.

ADS-B Out data is always sent about once per second (well assuming you have it turned on and its working OK). The data sent from even a Mode-S interrtogation is different from the ADS-B 1090ES data.

The Power consumption implication on broadcast are insignificant. The issue of adding GPS to say a current Trig transponder is the power consumption of the GPS itself. Some certified GPS units can have relatively high power consumption. Transponders are being interrogated all the time, by SSR, TCAS and TCAD systems. All that stuff can add to power consumption but the interrogation rates there can be orders of magnitude higher than the ~1/second ADS-B Output.

[snip]

[xcnick]

On Friday, February 17, 2017 at 8:44:40 PM UTC-8, Paul Villinski wrote:

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

I am watching xcsoar to perhaps be the first.

Using Avare and dongle too. I find they always broadcast the weather even if you are not getting traffic. Very handy when getting home.

[Andy Blackburn[_3_]]

On Saturday, February 18, 2017 at 10:56:10 AM UTC-8, Darryl Ramm wrote:
>
> The Stratux for FLARM protocol stuff was really people tinkering with ideas and I don't think it went anywhere.


Yup. It's not ready for non-programmers/hardware geeks.

Andy

[kinsell]

On 02/18/2017 10:44 AM, Dave Nadler wrote:
> On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
>> Wondering if ADS-B equipped aircraft have any advantage should they
>> need search and rescue, given that they broadcast their ID and coordinates.
>
> 1) ADS-B ground stations logging data would need to receive ADS-B down
> to near ground level to get close to the crash site. A glider can travel
> a long distance from the altitudes mentioned as ground-station receive
> floor in this thread.

I think people don't appreciate how extensive the FlightAware network
really is. I've tracked traffic down to landing, and then taxiing back
to their hangar from 30 miles away. Would be interesting if Sarah went
to flightaware.com, put in her N number, and saw what data the system
has on her flights.

The system even has some capability of tracking Mode S targets with
triangulation, although with reduced accuracy and coverage.


>
> 2) FLARM can assist in SAR (and has done a number of times). This requires
> other gliders flying in FLARM-range of the crash, otherwise the search
> area will not be narrowed to a helpful size. And the FLARM log files need
> to be promptly recovered from gliders in the area and forwarded to FLARM
> for analysis.
>

[Darryl Ramm]

On Sunday, February 19, 2017 at 9:08:38 PM UTC-8, kinsell wrote:
> On 02/18/2017 10:44 AM, Dave Nadler wrote:
> > On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
> >> Wondering if ADS-B equipped aircraft have any advantage should they
> >> need search and rescue, given that they broadcast their ID and coordinates.
> >
> > 1) ADS-B ground stations logging data would need to receive ADS-B down
> > to near ground level to get close to the crash site. A glider can travel
> > a long distance from the altitudes mentioned as ground-station receive
> > floor in this thread.
>
> I think people don't appreciate how extensive the FlightAware network
> really is. I've tracked traffic down to landing, and then taxiing back
> to their hangar from 30 miles away. Would be interesting if Sarah went
> to flightaware.com, put in her N number, and saw what data the system
> has on her flights.
>
> The system even has some capability of tracking Mode S targets with
> triangulation, although with reduced accuracy and coverage.
>

I'm not sure what point you are making. Flightaware tracking for flights without an IFR flight plan is next to useless.

Airport surface movement tracking at an airport that has ADS-B ground station coverage does not relate to say mountainous areas where lots of glider fly that might have large areas of poor ADS-B coverage. Like around parts of the CA/NV great Basin. ]

The original question of how useful is this really comes down to where you are flying and what accident/landout/SAR scenarios you are trying to mitigate. I really don't see the point of worrying too much about ADS-B for this.. With InReach tracking available at relatively low cost, and supporting text messaging (handy for non-emergency landouts). Sure the FAA can pull up records of ADS-B flight tracks, if you happen to be in ground station coverage, How long that takes to get in SAR situation who knows, and if you think the glider just landed out, well good luck... just go get an InReach (and maybe consider a 406MHz PLB as backup). If you really really cared about this I'd go ask local SAR and FAA folks how they would use that data (for a VFR aircraft with no flight plan/no flight following) and how fast that data is available to SAR organizations.

[Andrzej Kobus]

On Monday, February 20, 2017 at 1:33:22 AM UTC-5, Darryl Ramm wrote:
> On Sunday, February 19, 2017 at 9:08:38 PM UTC-8, kinsell wrote:
> > On 02/18/2017 10:44 AM, Dave Nadler wrote:
> > > On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
> > >> Wondering if ADS-B equipped aircraft have any advantage should they
> > >> need search and rescue, given that they broadcast their ID and coordinates.
> > >
> > > 1) ADS-B ground stations logging data would need to receive ADS-B down
> > > to near ground level to get close to the crash site. A glider can travel
> > > a long distance from the altitudes mentioned as ground-station receive
> > > floor in this thread.
> >
> > I think people don't appreciate how extensive the FlightAware network
> > really is. I've tracked traffic down to landing, and then taxiing back
> > to their hangar from 30 miles away. Would be interesting if Sarah went
> > to flightaware.com, put in her N number, and saw what data the system
> > has on her flights.
> >
> > The system even has some capability of tracking Mode S targets with
> > triangulation, although with reduced accuracy and coverage.
> >
>
> I'm not sure what point you are making. Flightaware tracking for flights without an IFR flight plan is next to useless.
>
> Airport surface movement tracking at an airport that has ADS-B ground station coverage does not relate to say mountainous areas where lots of glider fly that might have large areas of poor ADS-B coverage. Like around parts of the CA/NV great Basin. ]
>
> The original question of how useful is this really comes down to where you are flying and what accident/landout/SAR scenarios you are trying to mitigate. I really don't see the point of worrying too much about ADS-B for this. With InReach tracking available at relatively low cost, and supporting text messaging (handy for non-emergency landouts). Sure the FAA can pull up records of ADS-B flight tracks, if you happen to be in ground station coverage, How long that takes to get in SAR situation who knows, and if you think the glider just landed out, well good luck... just go get an InReach (and maybe consider a 406MHz PLB as backup). If you really really cared about this I'd go ask local SAR and FAA folks how they would use that data (for a VFR aircraft with no flight plan/no flight following) and how fast that data is available to SAR organizations.

Darryl, having done analysis on that data for business purposes I have to disagree. In fact, the network of receivers is very dense. There are a lot of enthusiasts with Stratux receivers uploading tracking data all the time. FAA is not able to track me reliably but the same is not true with individuals across USA with their Stratux devices connected to Flightaware.

[Darryl Ramm]

You disagree with what exactly? Show us where you find ADS-B coverage via Flightaware of glider flights, especially in some of the poor FAA ADS-B coverage areas of say the great basin.

My main point is with alternate products available, thinking about ADS-B from a SAR perspective is a lot less important/just not that interesting.

Everything else is really dependent on what scenario you are trying to cover and where you fly. Without that thinking it's a near useless question to ask. Can ADS-B help? Sure it might. And sure it might not. The question needs to be where/how/when could it help and to answer that start looking at the coverage (and access to that data) where you fly.

[Sarah[_2_]]

Just for the record, I did look up my N number on FlightAware. Turns out I flew a straight out flight KLAF -> KAZO, 233 KM at 257 KPH ! Not bad! Must be a record!

Just kidding - someone have misregistered their N-number.

I've found FlightAware pretty unreliable for VFR flights, even close to a metro class B.



On Sunday, February 19, 2017 at 11:08:38 PM UTC-6, kinsell wrote:
> On 02/18/2017 10:44 AM, Dave Nadler wrote:
> > On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
> >> Wondering if ADS-B equipped aircraft have any advantage should they
> >> need search and rescue, given that they broadcast their ID and coordinates.
> >
> > 1) ADS-B ground stations logging data would need to receive ADS-B down
> > to near ground level to get close to the crash site. A glider can travel
> > a long distance from the altitudes mentioned as ground-station receive
> > floor in this thread.
>
> I think people don't appreciate how extensive the FlightAware network
> really is. I've tracked traffic down to landing, and then taxiing back
> to their hangar from 30 miles away. Would be interesting if Sarah went
> to flightaware.com, put in her N number, and saw what data the system
> has on her flights.
>
> The system even has some capability of tracking Mode S targets with
> triangulation, although with reduced accuracy and coverage.
>
>
> >
> > 2) FLARM can assist in SAR (and has done a number of times). This requires
> > other gliders flying in FLARM-range of the crash, otherwise the search
> > area will not be narrowed to a helpful size. And the FLARM log files need
> > to be promptly recovered from gliders in the area and forwarded to FLARM
> > for analysis.
> >

[Eric Greenwell[_4_]]

I just looked up my Phoenix N42EJ, which has flown about 400 hours with ADSB in
the last 3 years, including a flight from Florida. Flightaware had one flight
track for me, and that one was in Dec 2014.

Sarah wrote on 2/20/2017 2:37 PM:
> Just for the record, I did look up my N number on FlightAware. Turns out I flew a straight out flight KLAF -> KAZO, 233 KM at 257 KPH ! Not bad! Must be a record!
>
> Just kidding - someone have misregistered their N-number.
>
> I've found FlightAware pretty unreliable for VFR flights, even close to a metro class B.
>
>
>
> On Sunday, February 19, 2017 at 11:08:38 PM UTC-6, kinsell wrote:
>> On 02/18/2017 10:44 AM, Dave Nadler wrote:
>>> On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
>>>> Wondering if ADS-B equipped aircraft have any advantage should they
>>>> need search and rescue, given that they broadcast their ID and coordinates.
>>>
>>> 1) ADS-B ground stations logging data would need to receive ADS-B down
>>> to near ground level to get close to the crash site. A glider can travel
>>> a long distance from the altitudes mentioned as ground-station receive
>>> floor in this thread.
>>
>> I think people don't appreciate how extensive the FlightAware network
>> really is. I've tracked traffic down to landing, and then taxiing back
>> to their hangar from 30 miles away. Would be interesting if Sarah went
>> to flightaware.com, put in her N number, and saw what data the system
>> has on her flights.
>>
>> The system even has some capability of tracking Mode S targets with
>> triangulation, although with reduced accuracy and coverage.
>>
>>
>>>
>>> 2) FLARM can assist in SAR (and has done a number of times). This requires
>>> other gliders flying in FLARM-range of the crash, otherwise the search
>>> area will not be narrowed to a helpful size. And the FLARM log files need
>>> to be promptly recovered from gliders in the area and forwarded to FLARM
>>> for analysis.
>>>
>

[kinsell]

I see flights on 16 different days going back to July of last year for
your ship (I have an Enterprise account).

Then if I log out of my account, I see what you saw, just one old
flight. It says registered users see 4 months of history. Don't know
why it would show you one old flight if you're not registered. Must be
a bug.




On 02/20/2017 04:56 PM, Eric Greenwell wrote:
> I just looked up my Phoenix N42EJ, which has flown about 400 hours with
> ADSB in the last 3 years, including a flight from Florida. Flightaware
> had one flight track for me, and that one was in Dec 2014.
>
> Sarah wrote on 2/20/2017 2:37 PM:
>> Just for the record, I did look up my N number on FlightAware. Turns
>> out I flew a straight out flight KLAF -> KAZO, 233 KM at 257 KPH ! Not
>> bad! Must be a record!
>>
>> Just kidding - someone have misregistered their N-number.
>>
>> I've found FlightAware pretty unreliable for VFR flights, even close
>> to a metro class B.
>>
>>
>>
>> On Sunday, February 19, 2017 at 11:08:38 PM UTC-6, kinsell wrote:
>>> On 02/18/2017 10:44 AM, Dave Nadler wrote:
>>>> On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski
>>>> wrote:
>>>>> Wondering if ADS-B equipped aircraft have any advantage should they
>>>>> need search and rescue, given that they broadcast their ID and
>>>>> coordinates.
>>>>
>>>> 1) ADS-B ground stations logging data would need to receive ADS-B down
>>>> to near ground level to get close to the crash site. A glider can
>>>> travel
>>>> a long distance from the altitudes mentioned as ground-station receive
>>>> floor in this thread.
>>>
>>> I think people don't appreciate how extensive the FlightAware network
>>> really is. I've tracked traffic down to landing, and then taxiing back
>>> to their hangar from 30 miles away. Would be interesting if Sarah went
>>> to flightaware.com, put in her N number, and saw what data the system
>>> has on her flights.
>>>
>>> The system even has some capability of tracking Mode S targets with
>>> triangulation, although with reduced accuracy and coverage.
>>>
>>>
>>>>
>>>> 2) FLARM can assist in SAR (and has done a number of times). This
>>>> requires
>>>> other gliders flying in FLARM-range of the crash, otherwise the search
>>>> area will not be narrowed to a helpful size. And the FLARM log files
>>>> need
>>>> to be promptly recovered from gliders in the area and forwarded to
>>>> FLARM
>>>> for analysis.
>>>>
>>

[kinsell]

FAA is finding large numbers of misconfigured ADS-B Out installations.
Have you run the compliance test to check for problems?

https://www.aopa.org/news-and-media/all-news/2016/may/pilot/pe_adsb


On 02/20/2017 03:37 PM, Sarah wrote:
> Just for the record, I did look up my N number on FlightAware. Turns out I flew a straight out flight KLAF -> KAZO, 233 KM at 257 KPH ! Not bad! Must be a record!
>
> Just kidding - someone have misregistered their N-number.
>
> I've found FlightAware pretty unreliable for VFR flights, even close to a metro class B.
>
>
>
> On Sunday, February 19, 2017 at 11:08:38 PM UTC-6, kinsell wrote:
>> On 02/18/2017 10:44 AM, Dave Nadler wrote:
>>> On Tuesday, February 14, 2017 at 10:30:57 PM UTC-5, Paul Villinski wrote:
>>>> Wondering if ADS-B equipped aircraft have any advantage should they
>>>> need search and rescue, given that they broadcast their ID and coordinates.
>>>
>>> 1) ADS-B ground stations logging data would need to receive ADS-B down
>>> to near ground level to get close to the crash site. A glider can travel
>>> a long distance from the altitudes mentioned as ground-station receive
>>> floor in this thread.
>>
>> I think people don't appreciate how extensive the FlightAware network
>> really is. I've tracked traffic down to landing, and then taxiing back
>> to their hangar from 30 miles away. Would be interesting if Sarah went
>> to flightaware.com, put in her N number, and saw what data the system
>> has on her flights.
>>
>> The system even has some capability of tracking Mode S targets with
>> triangulation, although with reduced accuracy and coverage.
>>
>>
>>>
>>> 2) FLARM can assist in SAR (and has done a number of times). This requires
>>> other gliders flying in FLARM-range of the crash, otherwise the search
>>> area will not be narrowed to a helpful size. And the FLARM log files need
>>> to be promptly recovered from gliders in the area and forwarded to FLARM
>>> for analysis.
>>>
>

[Andrzej Kobus]

On Monday, February 20, 2017 at 1:40:50 PM UTC-5, Darryl Ramm wrote:
> You disagree with what exactly? Show us where you find ADS-B coverage via Flightaware of glider flights, especially in some of the poor FAA ADS-B coverage areas of say the great basin.
>
> My main point is with alternate products available, thinking about ADS-B from a SAR perspective is a lot less important/just not that interesting.
>
> Everything else is really dependent on what scenario you are trying to cover and where you fly. Without that thinking it's a near useless question to ask. Can ADS-B help? Sure it might. And sure it might not. The question needs to be where/how/when could it help and to answer that start looking at the coverage (and access to that data) where you fly.

With your comment "Flightaware tracking for flights without an IFR flight plan is next to useless" That is not the case in the eastern USA. There are many non-gov sources that feed flightaware quite well.
Sure DeLorme or SPOT are the obvious choices emergencies but if you have ADS-B out, Flightaware can provide your last position information. It is not great but it is not useless.

[Charlie M. (UH & 002 owner/pilot)]

CAP uses other sources as well.....

https://www.aopa.org/news-and-media/all-news/2017/february/13/cap-technology-team-scores-second-save-in-month

[Darryl Ramm]

On Monday, February 20, 2017 at 5:33:42 PM UTC-8, Andrzej Kobus wrote:
> On Monday, February 20, 2017 at 1:40:50 PM UTC-5, Darryl Ramm wrote:
> > You disagree with what exactly? Show us where you find ADS-B coverage via Flightaware of glider flights, especially in some of the poor FAA ADS-B coverage areas of say the great basin.
> >
> > My main point is with alternate products available, thinking about ADS-B from a SAR perspective is a lot less important/just not that interesting.
> >
> > Everything else is really dependent on what scenario you are trying to cover and where you fly. Without that thinking it's a near useless question to ask. Can ADS-B help? Sure it might. And sure it might not. The question needs to be where/how/when could it help and to answer that start looking at the coverage (and access to that data) where you fly.
>
> With your comment "Flightaware tracking for flights without an IFR flight plan is next to useless" That is not the case in the eastern USA. There are many non-gov sources that feed flightaware quite well.
> Sure DeLorme or SPOT are the obvious choices emergencies but if you have ADS-B out, Flightaware can provide your last position information. It is not great but it is not useless.

I have no dispute that ADS-B *might* provide last position information. But there are are scenarios where it *will* be useless, where there is poor coverage from FAA or other sources. And those locations are ones of the probably more challenging SAR areas to start with. So again, folks need to stop asking general "might it help" questions and look at their particular locations where they fly and scenarios they care about (e.g. useful for loss/crash vs. landout).

Links to flight traces of ADS-B glider flights please.... (VFR only, not flight plan, and for the ones that do show up is were those flights on flight following?). My impression of Flightaware is VFR flight reporting is it is very poor. That is not wether there are trackers out there, there system is just not reporting most ofd that. In areas like the Great Basin/Sierras I would get an InReach (not Spot). Sure I'd also make sure that the club/FBO/friends knew the glider was say 1090ES Out equipped. Just like you want folks who care about you today to know if the glider is/is not transponder equipped (and Mode C or S) and know to pass that info onto SAR. You should have all that written down in a document that says who to call when and has all that extra information written down.

[Andy Blackburn[_3_]]

On Monday, February 20, 2017 at 6:23:15 PM UTC-8, Darryl Ramm wrote:
> On Monday, February 20, 2017 at 5:33:42 PM UTC-8, Andrzej Kobus wrote:
> > On Monday, February 20, 2017 at 1:40:50 PM UTC-5, Darryl Ramm wrote:
> > > You disagree with what exactly? Show us where you find ADS-B coverage via Flightaware of glider flights, especially in some of the poor FAA ADS-B coverage areas of say the great basin.
> > >
> > > My main point is with alternate products available, thinking about ADS-B from a SAR perspective is a lot less important/just not that interesting.
> > >
> > > Everything else is really dependent on what scenario you are trying to cover and where you fly. Without that thinking it's a near useless question to ask. Can ADS-B help? Sure it might. And sure it might not. The question needs to be where/how/when could it help and to answer that start looking at the coverage (and access to that data) where you fly.
> >
> > With your comment "Flightaware tracking for flights without an IFR flight plan is next to useless" That is not the case in the eastern USA. There are many non-gov sources that feed flightaware quite well.
> > Sure DeLorme or SPOT are the obvious choices emergencies but if you have ADS-B out, Flightaware can provide your last position information. It is not great but it is not useless.
>
> I have no dispute that ADS-B *might* provide last position information. But there are are scenarios where it *will* be useless, where there is poor coverage from FAA or other sources. And those locations are ones of the probably more challenging SAR areas to start with. So again, folks need to stop asking general "might it help" questions and look at their particular locations where they fly and scenarios they care about (e.g. useful for loss/crash vs. landout).
>
> Links to flight traces of ADS-B glider flights please.... (VFR only, not flight plan, and for the ones that do show up is were those flights on flight following?). My impression of Flightaware is VFR flight reporting is it is very poor. That is not wether there are trackers out there, there system is just not reporting most ofd that. In areas like the Great Basin/Sierras I would get an InReach (not Spot). Sure I'd also make sure that the club/FBO/friends knew the glider was say 1090ES Out equipped. Just like you want folks who care about you today to know if the glider is/is not transponder equipped (and Mode C or S) and know to pass that info onto SAR. You should have all that written down in a document that says who to call when and has all that extra information written down.

If the question you are trying to resolve is should you buy ADS-B Out or a satellite tracker for the purpose of SAR, get a satellite tracker - preferably an InReach - unless you like "maybe, sometime" as your SAR method. The possibility that someone can track you most places via ADS-B breadcrumbs seems a bit too much like a theoretical exercise. The lower you get, the less likely you will be picked up by a ground station, and gliders can go quite far from low altitudes before landing. Satellites can see you on the ground and a satellite messenger can send a "come get me" message - to crew or SAR depending on your need.

Andy Blackburn
9B

[Paul Villinski]

That's not quite my question -- glider has Spot tracker -- it's more a question of whether, in addition to ADS-B's intended traffic awareness/avoidance function and the possible cockpit display of TIS-B and FIS-B, there is any significant added value in terms of Search and Rescue. Looking at whether that "maybe, sometimes" tips the scale in favor of the additional investment to equip. Obviously, not a reason on its own to equip.

Looking at the map Sarah pointed to in an earlier post, the FAA indicates that coverage even at 500' AGL is nearly continuous in the area NW of NYC where I typically fly. Looking at the area around Marfa, TX, where I sometimes fly, and where one would really like to be found if needed, there appears to be almost no coverage, even at 5000'. So, as has been pointed out, the answer largely hinges on where you are flying.

In short, I think the answer is "couldn't hurt."

[Surge]

How does satellite based ADS-B monitoring like Aireon's space-based global surveillance system fit into the picture?

[Darryl Ramm]

On Monday, February 20, 2017 at 10:16:42 PM UTC-8, Surge wrote:
> How does satellite based ADS-B monitoring like Aireon's space-based global surveillance system fit into the picture?

If that (A) ever actually happens and (B) ever monitor flights over the continental USA and (C) ever want to sell that data (to the FAA or commercially) then it might be interesting. But nothing is perfect, and down low amongst terrain/mountains you may get some obscuration (just lik with Spot or InReach... but hopefully better given the transmit power). An ADS-B Out antenna mounted under a Carbon Fiber glider might not work so well. Their target platform is an airliner with Diversity/top mounted 1090ES out antenna. Their business model now is selling high-value transoceanic data services to ATC providers.

Anybody mentioned a Garmin InReach is damn good value for money... :-)

[Mike Schumann[_2_]]

On Monday, February 20, 2017 at 1:40:50 PM UTC-5, Darryl Ramm wrote:
> You disagree with what exactly? Show us where you find ADS-B coverage via Flightaware of glider flights, especially in some of the poor FAA ADS-B coverage areas of say the great basin.
>
> My main point is with alternate products available, thinking about ADS-B from a SAR perspective is a lot less important/just not that interesting.
>
> Everything else is really dependent on what scenario you are trying to cover and where you fly. Without that thinking it's a near useless question to ask. Can ADS-B help? Sure it might. And sure it might not. The question needs to be where/how/when could it help and to answer that start looking at the coverage (and access to that data) where you fly.

One BIG reason that you don't see many glider flights on FlightAware is that there are currently almost no ADS-B OUT equipped gliders flying in the US.. The fleet of Dynon Skyview equipped Phoenix Motorgliders probably make up the bulk of these ADS-B equipped gliders.

In SW Florida, I can consistently see my flight traces on FlightAware down to 500' AGL. Granted, out west there is less coverage. If you fly out there, you can get a FREE ADS-B receiver from FlightAware (http://flightaware.com/adsb/request) to enhance their coverage. All you need is an internet connection. Right now they are specifically targeting Montana, Wyoming, North and South Dakota, and west Texas for this offer.

In those areas where FlightAware has sufficient coverage, and they won't provide you a free receiver, you can make your own for ~$200, and they will give you a free Enterprise account for providing data to their network.

Ultimately, we are going to see global ADS-B coverage with satellite based receivers. The satellites are starting to be launched. If the FAA signs up for this, we could see national coverage down to ground level.

Nobody is arguing that today it's not a good idea to invest in SPOT or DeLorme devices. The point is that ADS-B is the future and that the investment in ADS-B OUT is going to be a smart move in the long run.

[Andy Blackburn[_3_]]

On Monday, February 20, 2017 at 10:35:06 PM UTC-8, Mike Schumann wrote:
> On Monday, February 20, 2017 at 1:40:50 PM UTC-5, Darryl Ramm wrote:
> > You disagree with what exactly? Show us where you find ADS-B coverage via Flightaware of glider flights, especially in some of the poor FAA ADS-B coverage areas of say the great basin.
> >
> > My main point is with alternate products available, thinking about ADS-B from a SAR perspective is a lot less important/just not that interesting.
> >
> > Everything else is really dependent on what scenario you are trying to cover and where you fly. Without that thinking it's a near useless question to ask. Can ADS-B help? Sure it might. And sure it might not. The question needs to be where/how/when could it help and to answer that start looking at the coverage (and access to that data) where you fly.
>
> One BIG reason that you don't see many glider flights on FlightAware is that there are currently almost no ADS-B OUT equipped gliders flying in the US. The fleet of Dynon Skyview equipped Phoenix Motorgliders probably make up the bulk of these ADS-B equipped gliders.
>
> In SW Florida, I can consistently see my flight traces on FlightAware down to 500' AGL. Granted, out west there is less coverage. If you fly out there, you can get a FREE ADS-B receiver from FlightAware (http://flightaware.com/adsb/request) to enhance their coverage. All you need is an internet connection. Right now they are specifically targeting Montana, Wyoming, North and South Dakota, and west Texas for this offer.
>
> In those areas where FlightAware has sufficient coverage, and they won't provide you a free receiver, you can make your own for ~$200, and they will give you a free Enterprise account for providing data to their network.
>
> Ultimately, we are going to see global ADS-B coverage with satellite based receivers. The satellites are starting to be launched. If the FAA signs up for this, we could see national coverage down to ground level.
>
> Nobody is arguing that today it's not a good idea to invest in SPOT or DeLorme devices. The point is that ADS-B is the future and that the investment in ADS-B OUT is going to be a smart move in the long run.

Mike - I don't think there is any immediate plan to support 2-way text or email messaging via ADS-B. Did I miss an announcement? I kind of like the idea that I can call for help, rather than waiting for somebody to figure it out from ADS-B breadcrumbs...or not..assuming your breadcrumbs were received...and/or assuming FAA supports satellite-based ADS-B.

Not that a cheap GPS source to go with your Trig isn't a good idea at some point in the future when it is truly cheap and legal to do..it's just a different use case and rationale really.

[Andy Blackburn[_3_]]

On Monday, February 20, 2017 at 8:54:08 PM UTC-8, Paul Villinski wrote:
> That's not quite my question -- glider has Spot tracker -- it's more a question of whether, in addition to ADS-B's intended traffic awareness/avoidance function and the possible cockpit display of TIS-B and FIS-B, there is any significant added value in terms of Search and Rescue. Looking at whether that "maybe, sometimes" tips the scale in favor of the additional investment to equip. Obviously, not a reason on its own to equip.
>
> Looking at the map Sarah pointed to in an earlier post, the FAA indicates that coverage even at 500' AGL is nearly continuous in the area NW of NYC where I typically fly. Looking at the area around Marfa, TX, where I sometimes fly, and where one would really like to be found if needed, there appears to be almost no coverage, even at 5000'. So, as has been pointed out, the answer largely hinges on where you are flying.
>
> In short, I think the answer is "couldn't hurt."

[Andy Blackburn[_3_]]

On Monday, February 20, 2017 at 8:54:08 PM UTC-8, Paul Villinski wrote:
>
> In short, I think the answer is "couldn't hurt."

Couldn't hurt, but if you have to choose between ADS-B Out and upgrading from Spot to InReach, the latter will likely prove far more beneficial (and better bang for your buck) if you are worried about being able to summon help to the right location when the time comes.

Andy Blackburn
9B