The FAA released guidance clearing the way for the use of five-knot increments in speed adjustments, rather than 10 knots. The guidance, the agency said, is part of its effort to increase its performance-based navigation activities. “To support deployed and planned NextGen capabilities, it is necessary to allow for the use five-knot increment speed,” it said.

NBAA noted that the change might initially “give some business aviation pilots pause,” but is designed to help make the airspace more efficient, as the FAA moves from distance-based separation to time-based metering of air traffic.

Rich Boll, chairman of NBAA’s ATC, Airspace and Flight Technologies Working Group, noted that that the change enables controllers to more precisely tune aircraft speeds and lead to more direct routing. Aircraft may be slowed sooner, but flight time will be less with the change in speed adjustments, Boll said.

NBAA anticipates the change initially will be more noticeable on approaches, but eventually will be used throughout the National Airspace System.