Legislation nearing completion in the US Congress will require the US Federal Aviation Administration to initiate a rulemaking within one year to mandate aircraft flying in "capacity constrained airspace" or at "capacity constrained airports" to equip with automatic dependent surveillance-broadcast (ADS-B) "in" surveillance systems by 2020.
The direction, part of the 2012-2015 FAA funding bill expected to be approved this week or next, is in direct contradiction to the 17 November recommendations from an aviation rulemaking committee (ARC) tasked by the FAA with evaluating the same technology.
While operators are already required to equip aircraft with ADS-B "out" equipment as the surveillance backbone of the FAA's next generation air transportation system (NextGen), the ARC determined that an economic case could not be made to justify the extra cost of mandating ADS-B "In".
ADS-B "out" broadcasts an aircraft's GPS-based position for air traffic surveillance purposes while ADS-B "in" brings surveillance and other information into an aircraft for advanced operations like in-trail procedures.
The ARC concluded that no near- or mid-term business case could be made for requiring operators to purchase ADS-B "in" equipment due to the immaturity of applications and uncertainties in the achievable benefits of the technology.
Under the new legislation, the FAA's new chief NextGen officer, a position also created in the bill, will be required to verify that the ADS-B ground network is "installed and functioning" before issuing an interim or final rule for equipage.
The bill also requires the FAA within 18 months to develop a plan for using ADS-B technology "for surveillance and active air traffic control in specific regions of the US with the most congested airspace".