The FAA released details of a new ADS-B-based oceanic airspace trial that began October 26 to reduce longitudinal separation between participating aircraft in Oakland Air Route Traffic Control Center’s oceanic control area. The current trial applies to aircraft climbing and descending and is designed to prove that more aircraft will be able to fly at their requested altitudes using the ADS-B-enabled reduced separation standards.

A number of conditions must be satisfied for controllers to apply reduced separation standards during the trial period, however. Once an aircraft has been identified as participating in the trial, it must be in contact with ATC via controller-pilot datalink communications (CPDLC). The speed differential between participating aircraft cannot exceed Mach 0.06, and altitude differential cannot exceed 2,000 feet. Trial aircraft must both be traveling in the same direction, already maintaining an assigned altitude and not cleared for any sort of route deviation. If the trial is successful, the FAA might use the ADS-B in-trail program as an enhancement to the standard Ocean 21 software Oakland Center currently uses in oceanic airspace. – R.P.M.