SkyhookBy: John J. Nance Skyhook is a top secret, high tech computer program designed to save planes in trouble. But when a test flight goes awry over the Gulf of Alaska, Ben Cole, the brains behind the experiment, finds another kind of trouble as he searches for the suspected saboteur. Meanwhile, April Rosen takes off on her own investigationto exonerate her father, whose own plane narrowly escaped a midair collision over the same patch of sea. Now, both of