IFALPA asks for simpler waypoint system over the North Atlantic - Curt Lewis

Pilots press for simpler oceanic waypoint convention

Cockpit crew representatives have outlined measures they believe should be taken to mitigate safety risks presented by reducing lateral separation to 25nm on North Atlantic tracks.

Initial trials of the reduced-separation scheme - known as 'RLatSM' - commenced last December, introducing the option to assign transoceanic aircraft to fly a route which is offset by 0.5° from core tracks.

But the International Federation of Air Line Pilots' Associations is striving to change the naming convention of waypoints to avoid possible navigation errors.

Canada's Gander and Ireland's Shanwick oceanic centres, which handle traffic over the North Atlantic, do not have the capability to uplink full routes to aircraft flight-management systems, requiring crews to enter the waypoints manually.

Entering full 13-character latitude-longitude waypoints is prone to mistyping errors, says IFALPA, which claims this "routinely" occurs some 10-12 times annually.

IFALPA adds that a simpler five-character naming convention - designed to eliminate the need to type all 13 characters - uses identities for the 0.5° track waypoints which are similar to those for the regular tracks.

This requires the crew to distinguish between waypoints identified, for example, as 'N5020', '50N20' and '5020N'.

IFALPA argues that incorrect entry could result in a gross navigation error of some 30nm - less of a concern under the previous lateral separation of 60nm but a greater problem with the reduced separation of 25nm.

The association says it has "always strongly advocated" for alternative methods of waypoint data entry, and is backing the use of a five-character naming convention which uses 'H' - standing for 'half-degree' - on the new tracks.

"Unfortunately, few operators have adopted [this] format, requiring flight crews to manually enter the full 13-character [latitude-longitude] waypoint," it states.

It is looking to "encourage" operators to support the format ahead of planned expansion of the trial, and is seeking development of a "more logical" naming convention in the medium term.

IFALPA is also pressing for modification of contingency procedures for turnback, given that an aircraft needs 23-32nm to reverse course and, in reduced-separation oceanic airspace, will impinge on adjacent tracks.

While the initial trial has concentrated on cruise altitudes between 35,000ft and 39,000ft, the expansion will extend the scheme to all North Atlantic oceanic tracks.