Nobody saw this coming, nobody knows why it happened, and nobody knows precisely where it is. That, essentially, is the story of Flight MH370—at least for now. The disappearance of the Malaysia AirlinesBoeing 777 on March 8 has been one of the most extraordinary events ever to befall Malaysia—and one of the world's greatest aviation mysteries.

On a routine flight between Kuala Lumpur and Beijing, moments after air-traffic controllers in Kuala Lumpur handed the flight over to their counterparts in Ho Chi Minh City, the plane's...