A typical routing would be: DCT KONAN UL607 EVRIN DCT MALOT/M081F350 DCT 53N020W 52N030W NATA JOOPY/N0462F360 N276C TUSKY DCT PLYMM.Oceanic boundary points for the NAT Tracks are along the FIR boundary of Gander on the west side, and Shanwick on the east side, as depicted on the charts above.They are aligned in such a way as to minimize any head winds and maximize tail winds impact on the aircraft.This results in much more efficiency by reducing fuel burn and flight time.Since 2017, aircraft can plan any flight level in the NAT HLA (high level airspace), with no need to follow ICAO standard cruising levels.
Waypoints on the route are identified by named waypoints (or "fixes") and by the crossing of degrees of latitude and longitude (such as "54/40", indicating 54°N latitude, 40°W longitude).
To make such efficiencies possible, the routes are created twice daily to take account of the shifting of the winds aloft and the principal traffic flow, eastward in North America evening and westward twelve hours later.
The first implementation of an Organised Track System across the North Atlantic was in fact for commercial shipping, dating back to 1898 when the North Atlantic Track Agreement was signed.
Westbound tracks (valid from UTC to UTC at 30W) are indicated by the letters A, B, C, D etc.
(as far as M if necessary, omitting I), where A is the northernmost track, and eastbound tracks (valid from UTC to UTC at 30W) are indicated by the letters Z, Y, X, W etc.
In 1966, the two agencies at Shannon and Prestwick merged to become Shanwick, with responsibility out to 30°W longitude; according to the official document "From 1st April, 1966, such a communications service between such aircraft and the said air traffic control centres as has before that date been provided by the radio stations at Ballygirreen in Ireland and Birdlip in the United Kingdom will be provided between such aircraft and the said air traffic control centre at Prestwick or such other air traffic control centre in the United Kingdom as may from time to time be nominated".