ADS-B question

I din't know which forum to put this in so I put it in 'general'. If there is a better place lemme know.

OK I have a SkyRadarD receiver and view on an iPad Mini with Wingx Pro.

Works great. Most of the time.

Displays the weather data nicely, except when it doesn't. To wit:

Headed back home from Triple Tree I'm flying along and have to divert 10 degrees for weather up ahead. Just as I request the deviation ATC comes back and says, "yeah we were going to advise or area of heavy precip ahead". I look at the ipad for confirmation and see, "nothing".

Now this works well and this was in an area I know they have coverage in (the Metar data was up to date in the area). So why would the WX not be shown?

This could be a software issue, a hardware issue, or an ADS-B broadcast issue. I'm leaning toward the latter as at other times it works just fine. This wasn't a delay issue as the weather in that area was persistent and it never showed any precip.

Just curious what other's experience has been.

Do you have ADSB out in your plane??

Mike, you do not need 'out' to get wx; just traffic from the ground.

OP: I have something similar; skyradar D2, iPad with WingX, plus a direct USB connection to a GRT HX. On my first go-around, I found that the little gps puck from SkyRadar was intermittant. The ADSB data transferred over to the HX even when the Skyradar GPS was not working (you can tell by looking at the little flashing LEDs on the Skyradar if it has got a gps lock). However, when the gps wasn't working, the transfer to the iPad and WingX didn't work either. So I suggest either your gps module couldn't see the satellites, or may be intermittant. You need to have this repeat, and observe the LEDs to see if you have a good gps signal.
Skyradar sent me a new gps module, and I've had no issues since then. I have the gps just sitting up on the glareshield (RV-10, fiberglass cabin top). I also glued the antennas to the fiberglass doorposts, works fine.

BobTurner said:

Mike, you do not need 'out' to get wx; just traffic from the ground.

Click to expand...

Hmmmmm-------just learned something, thanks.

new to ADSB in

I made a first flight with a SkyRadar DX just yesterday. It's connected to a iFly 700 with the serial cable. DX unit was just " resting" in the baggage compt. trying to decide where to install the unit, antennas and GPS puck. Wasn't over impressed. Ironically shortly after takeoff a hi wing Cessna went under me at about 500 feet neither of us saw each other until later!!. I did see KATL arrival traffic at 12,000 overhead while sitting on the ground. The DX unit received several hundred WX reports but I did not see any METARS TAF or other weather on the ifly. I also don't know where the disconnect is but I think I will hang on to my 396 Garmin XM weather a while longer. Anyone with pictures of how best to install these " portable" units?

I had an issue early on where I didn't think the METAR data was updating because when you click on an airport, say, and ask to see the WX you get a message that says "internet weather 2 hours old", or whatever the time was since you last synced up on the ground. When I actually looked at the METAR reprt, however, I did see that it was current for that location.

The intermittent display of live weather depiction is more vexing. The GPS works pretty well (drops out occasionally but I've seen that with every GPS I've owned) and I've failed to get the weather sometimes when when I know the GPS is working because the moving map function is updating normally. I'lll keep playing with it.

The traffic display is something I'm still figuring out as well. Since I have the dual input unit I thought I'd be getting traffic data pretty much anytime I was around a Class B as the airline traffic would be triggering broadcasts. Doesn't seem to be the case. Sometimes I do, sometimes I don't. I think the only time I see the traffic is when a ADS-B out GA aircraft triggers the broadcast. I flew through Charlotte Class B and ATC called a airliner a couple miles from me. No problem as I saw it before they called and it was no factor anyway. But it never showed on the traffic display. Flying into Triple Tree the screen practically lit up with all the GA traffic. I still have a lot to learn about how this system is supposed to work and how it actually does in practice.

I have some antenna pictures in the GRT SkyRadar supplement, here: http://grtavionics.com/Radenna%20Skyradar%20A2.pdf Some of the guys mounted the SkyRadar under the panel and ran the antennas out to the corners of the windscreen roll bar. James mounted his whole SkyRadar unit upside down on a bracket above the baggage area of his 6. The antennas should be mounted within view of the ground through a window, so Dennis if you've got it sitting on the baggage compartment floor, it might not work very well.

I'm glad to hear that about the SkyRadar GPS. Well not glad... but it might explain two accounts I've heard that weather was right in front of the plane but it didn't show up on the screen, even though the radar indicator said it was current.

NOT PERFECT YET!

Just to be clear about my experience, the SkyRadar D2 would not display ADSB info on my iPad, with neither WingX nor the SkyRadar software running, unless the Skyradar GPS had a lock. Despite the fact that the iPad gps was working, and the WingX moving map was working. (This was thru a WiFi connection. OTOH the information did appear on the GRT HX, thru the USB connection.)

A lot depends on the display software. For example (Katie please note!) my GRT Hx still will not display ADSB-supplied TFR info, but TFRs do appear on the iPad and WingX.

Most of the software offers "traffic filters". In the HX I know what it is and how to configure it, but I still have not figured out what is or is not filtered out when I select "filter on" with WingX!

I will say, in your case with the DX, it sounds like only 978 MHz is working and not 1090 MHz.

Once again, it bears repeating, that these boxes will NOT show traffic unless either (1) that traffic has an ADSB-out box that is transmitting or (2) that traffic is being picked up by ATC radar, you have an ADSB-out box, and you are within range of an ADSB ground station (need all three).

IMHO traffic info is nearly useless unless the display is panel mounted. Or you choose to fly looking down at your iPad in your lap all the time. But remember, at this point in time, you will not pick up most traffic (see above). You only look at wx from time to time, so a display in your lap is okay for that.

I hid my Skyradar box under the panel; glued the two antennas to the two door posts; threw the gps puck on the glare shield. It works just fine.

In my installation (RV-4) I mounted the Skyradar unit on the support frame for the roll bar, the GPS puck on top of the roll bar (great view of sky there), and use two external antennas ("transponder" stub types) mounted on the belly of the aircraft.

My understanding is that if an ADS-B aircraft is communicating with the ADS-B ground site in an area it triggers a broadcast of all ADS-B out equipped traffic as well as all mode C traffic currently broadcasting in the area. That seems to be the case but I only seem to get it if the broadcast is triggered by the lower frequency ADS-B out equipped (GA) aircraft and not the higher frequency Class A approved (turbine) traffic. My understanding is if I had ADS-B out I would receive traffic data out directly from other ADS-B equipped AC as well.

As far as the GPS. When the GPS puck working through the Skyradar Unit loses sync or whatever I get an indication on my WINGX display (ipad) that GPS LOST. This can go and come back in a few seconds and doesn't happen all that often. I'm using WIFI to connect between the ipad and the SkyRadar unit.

I don't expect to use the traffic feature all that much more a a curiosity and to give me a overview as I approach a terminal area. To rely in it for anything other than that seems suicidal as the system is far from perfect. Besides I can't fly with my head down. Weather pretty much the same but it is helpful to plan diversions around systems (AC is VFR only) and I wish I could figure out what is going on. In general the system works pretty well together. As a flight planning tool and moving map WingX is great. I'm sure the others are as well its just this is what I have and therefore what I know so far.

BobTurner said:

A lot depends on the display software. For example (Katie please note!) my GRT Hx still will not display ADSB-supplied TFR info, but TFRs do appear on the iPad and WingX.

Click to expand...

I've been told it will be done soon! Apparently it was a lot of work to get the TFRs to scale properly on our map.

As I understand it. If you have a dual band ADSB unit ie 978m and 1090mz you should see any plane with mode s directly with no ground station envolved.

"My understanding is that if an ADS-B aircraft is communicating with the ADS-B ground site in an area it triggers a broadcast of all ADS-B out equipped traffic as well as all mode C traffic currently broadcasting in the area."

This is true, BUT: (1) the broadcast is not on both frequencies, just the one that the transmitting aircraft says it is listening on. And (2) the traffic is only sent that is close to the the transmitting aircraft. I forget what "close" means, but it's a hockey puck shaped area something like 10 miles radius and +/- 2500' thick (I forget the real numbers). So if you're close to that transmitting aircraft you get some data relevant to you, if you're listening on the correct frequency (or both). If you're not within the hockey puck area, you don't get traffic relevant to you.

DennisRhodes said:

As I understand it. If you have a dual band ADSB unit ie 978m and 1090mz you should see any plane with mode s directly with no ground station envolved.

Click to expand...

That is, with a mode S-ES with an ADSB position source (gps ) hooked up to it.
For example, you will not see aircraft with the non ES mode S.

BobTurner said:

That is, with a mode S-ES with an ADSB position source (gps ) hooked up to it.
For example, you will not see aircraft with the non ES mode S.

Click to expand...

Nor will you see any "regular" non Mode S transponder, which is the majority of older transponders. You currently miss out on a significant amount of traffic.

I actually justified the purchase of the ADS B in /dual band unit just to get the WX and cancel my XM service for same. I'm going to have to see more with some reliability before I can cancel the XM service . At the present it's just a new toy to play with

Missing ADS B weather

I have seen this same issue of missing ADS B next radd weather on Wing X also while using I -levil. The Wing x shows AdS "OK" but weather was not shown. Not sure if this an ADS Issue or Wing x issue? It has happened several times, sometimes rebooting my ipad helps...I have also seen the issue of old metars, some airports are updated and others not......I am leaning towards believing this is a Wing X issue..

Steve

Remember, ADS-B is not fully operational and won't be until 2020. Until then, keep this in the back of your mind and don't expect it to be as reliable as when fully operational.

I think next time I go up I will load and use the native application that comes with the SkyRadar unit to see if I get different results that might point to WingX being the issue versus the SkyRadar hardware or the ADS-B service itself.

Yes come to think of it I should be receiving direct broadcasts from Mode S equipped aircraft. I know of two separate occasions when I've been less than 2 miles laterally and couple thousand feet vertically of airliners (assumption being they are Mode S equipped) with no traffic display.

The best explanation may just be the fact the system is not "operational" yet.

But all and all the system offers nice capabilities to augment your aircraft but prime motivation for me was to get in cockpit Wx and there seems there remain some bugs to be worked out yet. Ascribing fully to Murphy's maxims the two times when I really could have used up to date weather info were two times the system decided to say everything was CAVU while what was outside the windshield told a different tale.

ADS-B for add on

I am installing a Garmin 327. Anyone know about the Lynk system which is being developed to add ADS-B in and out, blue tooth for wx and traffic to the iPAD? for Approx $2000. Hopefully it also has a AHRS for back up attitude info

This would be great in that you would have something like the Stratus with it's info of wx, ADS-B in, and blue tooth info to your iPAD and it would add the ADS-B out.

Before getting something like this I just want to make sure it meets the requirements of the FAA 2020 ADS-B in and out.....if not I'll need to rethink/replan

GJHeck said:

I am installing a Garmin 327. Anyone know about the Lynk system which is being developed to add ADS-B in and out, blue tooth for wx and traffic to the iPAD? for Approx $2000. Hopefully it also has a AHRS for back up attitude info

This would be great in that you would have something like the Stratus with it's info of wx, ADS-B in, and blue tooth info to your iPAD and it would add the ADS-B out.

Before getting something like this I just want to make sure it meets the requirements of the FAA 2020 ADS-B in and out.....if not I'll need to rethink/replan

Click to expand...

Well, the Lynx is made by L-3, a major player in avionics. They said at Osh that the system will be certified for ADSB-out by the end of the year, and costs will start at $2K. Other than that they are not saying much. It might be worth waiting 6 months and see how it works out for them.
(There are no FAA "requirements" for ADSB-in, that's optional; and, for E-AB aircraft, there are no TSO or STC requirements for "in" avionics).

Thanks Bob.......any idea if it will have blue tooth to the iPAD for attitude info? My plan is to use a Mini iPAD for mapping, weather, and back up attitude.

I do not know. Their web site mostly is black, with a Lynx (the animal), so they are not saying much. Honestly I would be surprised if there is attitude data, since they seem to be aiming at the certified market (of course the adsb-out must meet TSOs even for EAB aircraft) and I doubt the FAA would allow that on a box for a normally certified airplane. Just my guess, of course.

Honestly, with backup panel mounted EFIS units now down to around $1K, I would look there rather than an iPad solution for backup IFR.

Sky radar GPS

I've been told I might be able to run the GRT antenna into the sky radar unit and negate the need for another puck on the aircraft....is this true? Whose done this?

Bart said:

I've been told I might be able to run the GRT antenna into the sky radar unit and negate the need for another puck on the aircraft....is this true? Whose done this?

Click to expand...

Bart said:

I've been told I might be able to run the GRT antenna into the sky radar unit and negate the need for another puck on the aircraft....is this true? Whose done this?

Click to expand...

Usually just one antenna per receiver, and they need to be matched.
What is true is that if you are using the Sky radar with its GPS (on the dash) connected via USB to the GRT HX, then the HX can use the Skyradar gps as an additional (or even only) gps source.