In a curious turn of events, the FAA last month found itself launching its nationwide ADS-B program in Washington and boosting the system’s air traffic benefits, while at the same time noting that, at the request of Alaska controllers, ADS-B returns had been removed–at least temporarily–from scopes at the Anchorage ARTCC. The timing of the two situations underscores the tension between the agency and Natca, its most obdurate union.

In Washington, FAA Administrator Marion Blakey was lauding ADS-B as “one of the most exciting programs to come out of the FAA,” and describing it as the backbone of NGATS, the future next-generation air transportation system.

Advocates of the system undoubtedly agreed, but the apparent lack of clear official procedures about the correct way to separate radar and ADS-B traffic on the Anchorage Center displays–even after more than four years of Capstone operations–“places my bargaining unit members’ careers at risk,” said Natca president John Carr in a letter to the FAA. However, ADS-B remains on the air in Alaska and, other than ATC tracking, operators still have its air-to-air traffic displays and all the other system benefits.

Nevertheless, the agency has now officially launched the nationwide project, with start-up funding of $80 million included in the FAA’s FY2007 budget request, and with agency officials now finalizing its overall implementation plan and the precise timing of its progressive segments. Currently, around 400 ground stations are envisioned, augmenting the 20 to 30 installations around Washington and along the East Coast.

Broadly, the current plan will start by taking advantage of mode-S transponders in airline and other aircraft–including some corporate jets–since many of these already emit the “extended squitter” signal bursts used in ADS-B.

Most recent mode-S transponders have this capability, and some earlier models can be upgraded to this standard with a software modification. These signals can be seen on ATC displays and, since they carry more data than the mode-S returns, will enhance the controllers’ appreciation of the overall scene–provided, of course, that the FAA and Natca agree on procedures for their use.

Pursuing a ‘Turnkey’ Contract
Implementation of the nationwide ground station network is expected to begin in 2008, possibly with an initial number of approximately 40 systems covering high-density and other key areas, with the balance following later against a target completion date of 2014. One of the timing uncertainties here is that the FAA has indicated its interest in a “performance-based” turnkey contract, where a bidder would finance, build, install, operate and maintain the equipment for an annual fee.

This is analogous to the current contract-tower arrangement but would be much more complex and, with an estimated cost that could eventually be pushing $1 billion, is larger than anything the agency has previously undertaken.

The move to a turnkey contract would be advantageous to the FAA, however, since a lease arrangement would relieve the cash-strapped agency of heavy capital costs. On the plus side, too, is the FAA’s expectation that over a 20-year period, ADS-B could save $1 billion through the retirement of more than 200 surveillance radars.

While AOPA has strongly supported the ADS-B program, it seems likely that its members will not be immediate beneficiaries since the ground-station rollout
is likely to concentrate on heavy traffic areas, with emphasis on high-altitude coverage. It is also not yet clear what the expected nationwide low-altitude coverage will be, with some industry observers speculating that many more than 400 ground stations will be required to cover general aviation needs as VORs are progressively decommissioned.

Mandatory equipage is also a traditional bete noire of AOPA, but while this certainly will be gradually introduced in certain controlled airspace, a general mandatory carriage ruling is not expected until closer to 2025.

One area that will see early, low-altitude ADS-B coverage will be the Gulf of Mexico, where the Helicopter Association International (HAI) has signed a Memorandum of Agreement with the FAA to install stations on oil platforms in the Gulf. The Gulf has always been less well served for navigation, communications, weather and surveillance than the mainland, and HAI will finally be getting the service it has long lobbied for. Serendipitously, perhaps, ADS-B will also answer the airlines’ need for radar-like service across the center of the Gulf.

Meanwhile, in the curious world of the federal bureaucracy, it is reported that FAA officials continue to prepare  analyses of the cost/benefits of ADS-B, to seek approval later this month for a go-ahead from the FAA’s top level Joint Resources Council to proceed with the project.