Peter Challan, VP of industry affairs for Harris, notes that some of American’s aircraft are already equipped with the necessary avionics from the CPDLC trials and “we’ll equip others” for demonstrations at five initial airports in the 2015 timeframe.
The FAA has not announced which airports will be selected.
The long-term benefit of datacomm will be the evolution to real-time coordination of flight-management system parameters automatically between the ground and the air, paving the way for 4-D trajectory-based operations (TBO).
With 4-D TBO, an aircraft will arrive at a desired waypoint within seconds of a pre-determined time in the flight plan, boosting capacity while decreasing congestion and fuel burn as well as human errors related to voice and data entry. Operators of legacy aircraft will either need new equipment or system upgrades to participate.
FAA says the “tipping point” to optimize user benefits of datacomm is about 1,900 aircraft.
The agency is hoping that airlines, seeing the benefits of DCIS through early demonstrations at the five airports starting in 2015, will want to voluntarily equip, a different tactic than the agency used for automatic dependent surveillance-broadcast (ADS-B)-“out,” the satellite-based surveillance system that will replace much of the legacy radar network after a 2020 equipage mandate comes due. The agency contracted with ITT Exelis in 2007 to deploy and operate the NextGen surveillance system, ADS-B. The system is expected to be fully operational in 2013, though aircraft operators will have until 2020 comply with the avionics mandate.
Demonstrated Merits
Dillingham says a “top challenge” for convincing airlines of the merits of NextGen in the near term is to demonstrate benefits from avionics already installed on an aircraft, including performance-based navigation (PBN) systems. PBN includes GPS approaches that mimic instrument landing system (ILS) Category 1 approaches (200-ft. decision height and 1/4-mi. visibility) and required navigation performance (RNP) procedures. With RNP, the aircraft is certified to maintain a predetermined accuracy in position and altitude, with real-time updates displayed to specially trained pilots via the avionics as the aircraft flies a custom-designed approach that can curve around noise-sensitive areas or obstructive terrain.
The FAA’s “Greener Skies” demonstration at the Seattle-Tacoma International Airport and nearby Boeing Field is meant to test RNP benefits for broader use. The initial project is one of many NextGen demonstrations under way, completed or envisioned, similar in number to the projects taking place in Europe under the Single European Sky ATM research (Sesar) program.
Locally created with national collaboration, the Greener Skies test—with Alaska Airlines as lead carrier—involves RNP approach procedures that diminish noise and increase the rate of arrivals to Sea-Tac’s closely spaced parallel runways in instrument meteorological conditions.