On Tuesday, December 1, 2015 at 9:15:46 PM UTC-8, Andy Blackburn wrote:
If I understand the specs for ADS-R (by which transponder returns are uploaded to ADS-B aircraft), you will have a 30-mile radius of targets provided to you. Need to check that.


Correction: Here are the details of TIS-B services for aircraft with ADS-B Out and an ADS-B ground station in range - which is pretty much everywhere in the continental US once you're above a couple thousand feet. I believe aircraft with ADS-B In, but not properly-configured ADS-B Out, will be able to receive TIS-B traffic information including traffic with UAT and 1090ES ADS-B Out as well as transponder-equipped radar targets, so long as they are in range of a ground station that is broadcasting to any aircraft that does have properly configured ASD-B Out to request TIS-B services - which is to say you can "listen in" on TIS-B traffic rebroadcasts meant for another aircraft - it'll just be traffic in a 15 nm radius around them, not you.

I think that means that if you are flying near Andrzej you'll see everything he sees - but I need to check what Flarm will put on the dataport and whether there is anything special about TIS-B traffic packets that would cause them not to be passed along by Flarm.

I thought it would be another year or two before these installations started showing up.

https://www.faa.gov/nextgen/library/...Smart_ADSB.pdf

Relevant passage:
Traffic Information Service-Broadcast (TIS-B): This air traffic advisory service provides
the altitude, ground track, speed and distance of aircraft flying in radar contact with controllers and within a 15-nautical-mile (nm) radius, up to 3,500 feet above or below the receiving aircraft's position. It can be received on both UAT and 1090 MHz. A general aviation aircraft equipped with ADS-B In can also receive position data directly from other aircraft broadcasting on the same ADS-B Out frequency. In addition, TIS-B enables pilots to see aircraft equipped with transponders flying nearby even if those aircraft are not equipped with ADS-B Out.