On May 27, 2010, the FAA published new rules (contained in 14 CFR §92.225 and §91.227) mandating airspace and avionics performance requirements after January 1, 2020. The avionics perform a function that is generally known as “ADS-B Out” which transmits precise location and other information about the aircraft to ground stations and other ADS-B equipped aircraft.

The ADS-B rule mandates ADS-B Out avionics performance when operating within the designated airspace, giving aircraft owners approximately 10 years to equip.

The ADS-B rule, like current transponder operating requirements, requires operators to have ADS-B Out avionics installed and operating in order to fly their aircraft in the busiest airspace, as described below:

•Class A, B, and C airspace.
•All airspace at and above 10,000 feet MSL (mean sea level) over the 48 contiguous United States and the District of Columbia.
•Within 30 nautical miles of airports listed in 14 CFR §91.225, from the surface up to 10,000 feet MSL.
•Class E airspace over the Gulf of Mexico from the coastline of the United States out to 12 nautical miles, at and above 3,000 feet MSL.
FAA Technical Service Orders (TSOs) describe the equipment approved for ADS-B operations. The ADS-B rule states that avionics must meet the standards of either TSO-C166b (for 1090ES link equipment) or TSO-C154c (for UAT link equipment). TSO-C166b is required in Class A airspace and either link can be used in all other airspace.

For more information about the FAA’s ADS-B program, visit www.adsb.gov.

Are my current avionics compatible?
For compliance to the proposed rule you will need an ADS-B Out transmit capability. However, to take full advantage of the ADS-B In services, your plane must be equipped with a certified receiver/transmitter and either a cockpit display or a Multi-Function Display (MFD). You will need to consult with a equipment manufacturer to determine if your avionics will be able to fully support ADS-B In or ADS-B Out, and for information on whether a retrofit or a new purchase will be required.

I hear this is going to be expensive. How much will it cost me?
There is no charge for ADS-B broadcast services. The government is installing the ground infrastructure at taxpayer expense to support both air traffic control and broadcast services. Under the proposed rule, starting in 2020 aircraft owners and operators who intend to operate in Class A, B, or C airspace, or in Class E airspace above 10,000 ft., would need to equip their aircraft for ADS-B Out performance capability. The price will vary depending on the equipment and manufacturer you choose. We believe prices will fall once competition among manufacturers increases.

http://www.faa.gov/about/office_org/hea ... formation/

The Trig TT31 transponder is Mode S with 1090ES and costs about $2400, the same as a KT76C Mode C transponder, and is plug compatible with the King. That's about the price for a GTX330 upgrade to 1090ES

The FAA rule makes it clear that a 1090ES will be acceptable for ADS-B out without antenna diversity, and the addition of a cheap ADS-B receiver will provide full FIS-B goodies.

There may be issues going forward because the Trig isn't TSO-C166b at the moment, but it does have the applicable Euro ADS-B approvals. I suspect the Garmin GTX33 1090ES also has an issue or two that will need adressing.