ITT was awarded the ADS-B contract in 2007. The company is scheduled to complete deployment by the end of 2013, and is on target to achieve that goal. The company estimates 700 ground stations will be needed—647 in the continental U.S., 41 in Alaska, nine in Hawaii, and one each in Guam, Puerto Rico and the U.S. Virgin Islands.

As of mid-November, ITT Exelis had constructed 516—or 74%—of the required ground stations. A further 73 stations were either under construction or in the final design stage.

Of the 516 stations completed so far, 511 are reporting on the ADS-B network. In addition to the ground stations, 223 interfaces between the ADS-B network and various FAA facilities will be needed. By mid-November 143—or 64%—of these had been installed and tested, with another 45 in final design and site preparation stage.

So it appears that the crucial ADS-B “Out” program is very much on track. However, to make the program a success, operators will have to ensure their aircraft have the necessary avionics equipage. The agency has set a deadline of 2020 for aircraft to have ADS-B capability in many types of airspace.

While ADS-B “Out” will undoubtedly yield significant ATM advantages, many experts consider that the real benefit for system users will come from ADS-B “In.” The “In” aspect would allow the display of other aircraft positions and weather data in the cockpit, improving situational awareness and potentially enabling more direct routings.

Although the FAA has set a deadline for ADS-B Out equipage, it has yet to do so for ADS-B In. An industry rulemaking advisory committee told the agency in September 2011 that it “does not support an equipage mandate” for ADS-B In.

In a report to the FAA, the advisory committee stressed that ADS-B In shows great promise. But “based on the current maturity of ADS–B In applications and uncertainties regarding the achievable benefits, there is not a . . . business case for near-term ADS–B In equipage.”

Instead of setting a mandate, the committee recommended that the FAA should incentivize voluntary equipage, and use demonstration projects to define benefits and standards for ADS-B In.

At this point, the FAA and industry appeared to be on the same page regarding ADS-B In. However, their hands could be forced by Congress. The FAA reauthorization bill passed in February orders the agency to develop an ADS-B In rule, that would, among other things, require equipage by aircraft in capacity-constrained airspace by 2020.

It is not yet clear how the FAA will satisfy this congressional requirement. To help it decide, the agency called for the ADS-B In advisory committee to “give us recommendations on how to proceed with ADS-B In, in light of the reauthorization bill,” an FAA spokesman tells Aviation Week. The FAA “recently received the [committee] report and [is] reviewing it.” The report will be published in the Federal Register after the FAA review, although there is no set timing on when that will occur, says the spokesman.