It would mean that within a 60-nm span, three tracks could be established instead of two, says Lachance. As a result, more tracks can be closer to the routes that are optimal because of wind and other conditions. “It will allow aircraft to benefit a lot more from the jet stream,” Lachance says.
If all goes according to plan, RLatSM could be introduced by Nav Canada and NATS in 2015. It would first be used on a trial basis at flight levels (FL) 350-390.
Efforts such as RLongSM and RLatSM allow pilot requests for more efficient altitudes to be granted more often. This means aircraft can adjust height according to wind conditions, and fly higher as their fuel load diminishes. Lachance says Nav Canada is working to educate pilots on its new capabilities. Many pilots have not been requesting altitude changes because they assume they will not be given clearance. “Now it's the other way around—we are asking them to make those requests, because they will often get approved.”
Nav Canada has implemented another feature it calls the request monitor tool, available to oceanic controllers through the Gander Automated Air Traffic System. If a pilot request for an altitude change is denied because of other traffic, the system stores the request and alerts the controller if that altitude change becomes available later. So the controller can go back to the pilot and offer the altitude change.
CPDLC is a precursor for many of these efforts. Nav Canada says equipage rates for FANS 1/A CPDLC is at about 65% over the North Atlantic. Nav Canada, NATS and the FAA all use it on oceanic routes. An International Civil Aviation Organization (ICAO) mandate entered force on Feb. 7, setting aside two of the core North Atlantic tracks—between FL 360-390 inclusive—where aircraft are required to use FANS 1/A equipment.
In addition to all these improvements, experts are looking further ahead—and more broadly—at how transatlantic traffic can be optimized.
By linking the U.S. and Europe, these routes connect two of the world's largest economies and air traffic systems, says Planzer. But inadequate coordination at either end means “we have, in effect, a non-system between these two big systems.” The two systems “only tangentially touch each other, and that causes problems.”
Planzer says coordination needs to occur among more players and cover the entire flight, beginning before takeoff, to make arrival times more predictable and to ensure smooth flows into congested airports at the other end of the trip.
To address this issue, Boeing is helping lead an “air bridge” project from the U.S. end that will link with a similar program underway in Europe. While the European effort has already been set up, the details of the U.S. initiative are still being ironed out.