North Pacific (NOPAC) Route System



The North Pacific (NOPAC) Route System is a designated group of Air Traffic Service (ATS) routes across the North Pacific between Alaska and Japan.


Traffic flow in the North Pacific is predictable due to factors such as consumer demand, time of day, time zone differences, winds aloft and airport noise restrictions. In general, eastbound traffic across the NOPAC is heavy between 0700Z and 2100Z whereas westbound traffic is heavy in the periods 1200Z to 1900Z and 2200Z to 0700Z.

NOPAC Route System

The North Pacific Route System is comprised of five (5) ATS routes, R220, R580, A590, R591 and G344, which transit the North Pacific between Alaska and Japan. The NOPAC system encompasses an altitude band from FL180 to FL410. On days when the NOPAC route system becomes the preferred routing for airilne dispatchers due to winds aloft, route saturation can occur.

Traffic Flow

The two northernmost ATS routes of the NOPAC route structurde, R220 and R580, are used predominately for westbound traffic whereas the three southernmost routes are used primarily for eastbound traffic with the exception that either R591 or B344 may be used for westbound traffic that will cross the Fukuoka/Anchorage FIR boundary between 0000Z and 0600Z. For a complete list of available altitudes by route and direction, consult the appropriate Jeppesen or alternate enroute manuals.

Transition Routes

Within the Fukuoka FIR, specific Oceanic Transition Routes (OTR's) have been established for aircraft transitioning to or from the NOPAC Route System. Although not as formalised, certain routes within the Anchorage FIR are used for the same purpose. Operators are encouraged to file on and off of the NOPAC routes using an appropriate transition routing. All flights in the FL180 to FL410 altitude band should be established on a NOPAC route prior to crossing the Fukuoka/Anchorage FIR boundary.

Related Articles

Further Reading


  • Enroute Data - Pacific



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