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I know that for ADS-B in the US to receive TIS-B information you need to be a participating aircraft (ie ADSB-Out). My question is more specifically, if you are flying an aircraft with a 1090ES transponder and have a stratux or similar ADSB-In device for your phone or tablet, will the system create the traffic puck around your aircraft and send TIS-B information for you?

FAA Traffic Puck

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  • $\begingroup$ Good question. As I understand it most 1090 MHz transponders transmit in dual-band mode, meaning 1090 and 978 (UAT) MHz. I'm more familiar with general aviation though, not necessarily the high altitude stuff. $\endgroup$ – Pugz Apr 14 '16 at 3:40
  • $\begingroup$ @pugz most, if not all 1090 MHz transponders broadcast ADS-B only on 1090 MHz. I am not aware of any dual band transmitters. $\endgroup$ – DeltaLima Apr 14 '16 at 21:46
  • $\begingroup$ @DeltaLima fair enough... I just know a lot of the general aviation ones that have 978 do both. $\endgroup$ – Pugz Apr 15 '16 at 4:49
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The answer is "yes" if

a) you configure your 1090 out system to request ADS-B uplink at 978 MHZ (this feature was added to the message structure in DO-260B) b) your 1090 ADS-B out message is confirming certain minimum "quality" standards related to both the quality of the position information (GPS Integrity or "NIC") and the quality of the avionics (SDA or system design assurance)and the quality of the install or SIL The specifics of what quality message triggers the system is under review by the FAA, but if you equipment is certified (TSO'd) and the install is in accordance with AC-20/165B you will be fine.

Note, if you have a UAT ADS-B you can specify which uplink frequency you want in the same way.

Further note - almost all ADS-B system are single band transmitters (ADS-B Out) and dual band receivers (ADS-B In).

Nuance - the uplink is broadcast to the quadrant (relative to the ground station) where you are flying. This can lead to aircraft with no or "below quality" ADS-B out receiving traffic intended for another aircraft. Depending on geometry this can create a partial traffic picture which can be quite misleading and potentially dangerous

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No, you will most likely not get a TIS-B service dedicated to your aircraft.

The TIS-B transmitting system creates a 'traffic puck' around aircraft that:

a) have a version 2 ADS-B transmitter,

b) transmit the proper quality indicators which indicates that the system is certified and is properly functioning, and

c) indicate in their ADS-B transmissions that the aircraft is equipped with ADS-B IN. (see FAA ADS-B FAQ #34, link provided by @Rigged4Flight )

Typically TIS-B will provide information on the same frequency as the ADS-B transmitter, but the ADS-B protocol allows for indicating a different technology is used for ADS-B IN. I am not sure whether the FAA system uses this information.

Note: currently version 1 ADS-B aircraft with sufficient data quality are also still eligible for TIS-B services, however this will change in the next couple of years.

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  • $\begingroup$ Thank you for the information. I was aware of facts a and b but couldn't find anything on C. Could you post a reference before I mark your answer as accepted? $\endgroup$ – Kevin Jablonski Apr 18 '16 at 0:31
  • $\begingroup$ Regarding DeltaLima's answer "C" (and Kevin's clarification question): DeltaLima is correct. The FAA FAQ on ADS-B says "To receive all ADS-B In services from the ADS-B ground infrastructure, aircraft must broadcast valid ADS-B Out messages that indicate their ADS-B-In capability." faa.gov/nextgen/programs/adsb/faq/#34 $\endgroup$ – Rigged4Flight Apr 28 '16 at 9:51
  • $\begingroup$ @Rigged4Flight thank you for the info; I have included it in the answer. $\endgroup$ – DeltaLima May 3 '16 at 9:34
  • $\begingroup$ @KevinJablonski answer is updated to include a reference (provided by R4F) $\endgroup$ – DeltaLima May 3 '16 at 9:34

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