Gol Transportes Aéreos Flight 1907
The Embraer had a set computer-generated flight plan to Air Traffic Control for the run north to Manaus. This would take N600XL over Brasília, where airway UZ6 would lead the airplane to Manaus. The computer requested a climb to FL370. Until Brasília, that direction was slightly to the east side of magnetic north. Since the airway to Manaus required a westerly turn over Brasília, the computer proposed a descent to 36,000, since it was supposed to be at that flight level by that point.