ADS-B question

I'm choosing what antennas I need to attach to my RV-9A, and that lead to ADS-B...of which I'm still confused. I've read the FAA webpages, the wiki article, but their information tends toward existing aircraft with legacy equipment. Thus I have this question:

For the many of us still building and equipping--no legacy equipment--and assuming I will want ADS-B In and Out capability--do I need a transponder on 1090 MHz? Or can I install only a UAT on 978 MHz?

Check this website, it may answer your questions. Dan

www.freeflightsystems.com/prod_adsb.htm

There's no talk at all about removing the requirement for transponders (where required), so the answer is yes, you'd wanna put one in.

If I understand correctly, you would want a 1090 if flying above 18000.

I have UAT with a navworx transceiver and like it. Unlike satellite weather, since it relies on transmitting ground stations, with ADSB you normally have to be flying to get weather. Get both in and out capability.

revenson said:

If I understand correctly, you would want a 1090 if flying above 18000.

I have UAT with a navworx transceiver and like it. Unlike satellite weather, since it relies on transmitting ground stations, with ADSB you normally have to be flying to get weather. Get both in and out capability.

Click to expand...

Apparently even below 18000 you need at least mode-c with UAT. What is your setup...do you have both a transponder and the UAT? How do you display weather?

From what I've learned now, for a new installation and to get both ADS-B in/out, the "cheapest" route would be a mode-s transponder on 1090 MHz (meets ADS-B out requirements), and a receive-only ADS-B gizmo on 978 MHz. The market is changing quickly at the moment, fortunately, it will be a year or more until I buy these goodies.

I have a mode S transponder (Garmin GTX-330) and a Navworx ADS-600B (both in and out). Transponder feeds info to the Navworx for ADSB transmit out. Display of traffic and weather is on the Grand Rapids EFIS. Grand Rapids currently supports traffic and weather, but not everything provided by the Navworx ADSB. TFR's are not programmed yet, for example.

I don't know whether you need mode S for ADSB. I bought it several years ago to get traffic (TIS-A). Now I've disabled the display of that, so as to not get duplicate traffic targets. The ADSB provides TIS-B traffic in a much broader area than mode-S provided TIS-A.

Talk with Bill Moffett at Navworx, or one of the other ADSB vendors for the best current info. I'm happy with ADS-B now...It's in the NW, California, and the SW, where I fly the most. But not yet implemented in Denver or Salt Lake Centers.

You do want the OUT so the ground station will transmit the traffic information for you. I have mode C, NavWrox ADS-600B and display on GRT EFIS. GRT displays only traffic direction and delta altitude. On weather, it is limited to METAR, TAF, Radar, and station AFC (Aviation Flight Condition). They are working on others. I really hope they will implement TFR soon.

On my trip to Florida I saw so much traffic. It was especially helpful when we descended through a hole and saw a traffic below the cloud a few miles behind and on the same direction.