North Atlantic Tracks (NATs) are daily high altitude transatlantic routes between western Europe and the eastern coast of North-America, which provide consistent separation between aircraft. Westward tracks are named incrementally from the beginning of the alphabet (A,B,C...), with the northernmost tracks named first. Similarly, eastward tracks are named incrementally from the end of the alphabet (Z,Y,X...), with the southernmost tracks named first. Daily updates for each direction allow for routing around weather systems and tracking of favourable tailwinds to improve efficiency.

The map below shows the current valid NATs and the upcoming published NATs, along with the permissible flight levels in each direction.
Track Valid From Valid To Route East Levels West Levels
A 04 Apr 1130 UTC 04 Apr 1900 UTC DINIM 51/20 51/30 50/40 48/50 NICSO 350 360 370 380 390
A 05 Apr 1130 UTC 05 Apr 1900 UTC DOGAL 55/20 55/30 54/40 52/50 TUDEP 340 350 360 370 380 390
Y 05 Apr 0100 UTC 05 Apr 0800 UTC ALLRY 51/50 51/40 51/30 51/20 DINIM ELSOX 330 340 350 360 370 380 390 400
Z 04 Apr 0100 UTC 04 Apr 0800 UTC LOMSI 55/50 56/40 57/30 57/20 SUNOT KESIX 320 330 340 350 360 370 380 390 400
Z 05 Apr 0100 UTC 05 Apr 0800 UTC JOOPY 49/50 49/40 48/30 48/20 48/15 ETIKI REGHI 330 350 360 380 390 400
Warning: Do not use this data for real-world aviation or navigation. No guarantee of current accuracy is given.