Boeing's second flight-test 787 Dreamliner landed shortly before midnight Monday after a nearly 14½-hour flight to the North Pole and back to Seattle’s Boeing Field.
Why the North Pole? It wasn’t to lobby Santa. The trip was designed to test the aircraft’s navigation gear in the sometimes-confusing high latitudes.
As aircraft move farther north, the conventional means of navigation, magnetic compasses and earthbound navigation signals, become unreliable. The plane has to rely more on its computer navigation systems to tell pilots where they’re flying.
One strange phenomenon occurs when the plane crosses over the North Pole. The plane’s direction-indicating instruments that previously showed the plane northbound, suddenly show it southbound though no change was made to the plane’s heading.