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
Warning: Do not use this data for real-world aviation or navigation. No guarantee of current accuracy is given.