North Atlantic Tracks , officially titled the North Atlantic Organised
Track System (NAT-OTS), is a structured set of transatlantic flight routes
that stretch from the eastern North America to western Europe across the
Atlantic Ocean, within the North Atlantic airspace region. They ensure that
aircraft are separated over the ocean, where there is little radar coverage.
These heavily travelled routes are used by aircraft flying between North
America and Europe, operating between the altitudes of 29,000 and 41,000 ft
(8,800 and 12,500 m) inclusive. Entrance and movement along these tracks is
controlled by special oceanic control centres to maintain separation between
aircraft.