First up, they have nadin who is essentially a combination of Chuck Norris, Albert Einstein, Jack Bauer, Rambo, and God. With her claimed skills, training, and knowledge she should be able to find the aircraft in a heartbeat.
Next up, is the "spiritual" and super-powered groups who find Christianity silly. They should be able to remote view the plane's location. Or astrally travel to the planes location. Or assign one of their elven fairies, garden gnomes, or ficitional spirit-guides to find the plane's location.
I think DU just doesn't care about people on the plane.