Passengers are cuing at Heathrow to board their 10-hour flight to Los Angeles. The departure board above the counter where they will soon scan their ticket and passport confirms this—the flight number and airline are displayed in small letters, while the biggest font reads "Los Angeles." There's no doubt in anyone's mind that this plane is bound for LAX. Correct though this may be, the three pilots on the flight deck are reviewing a flight plan from London to Seattle.