Like his role model, H.G. Wells, Crichton likes to moralize in his novels. In this slight, enjoyable thriller, the moral is the superficiality of TV, especially of its simplistic news coverage. Readers willing to overlook the irony of this message being broadcast by the man who created TV's top-rated drama (E.R.) will marvel again at Crichton's uncanny commercial instincts. The event that launches the story, conceived long before TWA Flight 800's last takeoff, is an airline disaster. Why did a passenger plane "porpoise"-pitch and dive repeatedly-enroute from Hong Kong to Denver, killing four and injuring 56 That's what Casey Singleton, v-p for quality assurance for Norton Aircraft, has to find out fast. If Norton's design is to blame, its imminent deal with China may collapse, and the huge company along with it. With Casey as his unsubtle focus-she's one of the few Crichton heroines, an all-American gal who's more plot device than character-Crichton works readers through a brisk course in airline mechanics and safety. The accretion of technical detail, though fascinating, makes for initially slow reading that speeds up only fitfully when Casey is menaced by what seem to be union men angry over the Chinese deal. But as she uncovers numerous anomalies about the accident, and as high corporate intrigue and a ratings-hungry TV news team enter the picture, the plot complicates and suspense rises, peaking high above the earth in an exciting re-creation of the flight. It's possible that Crichton has invented a new subgenre here-the industrial thriller-despite elements (video-generated clues, for one) recycled from his earlier work. It's certain that, while this is no Jurassic Park, he's concocted another slick, bestselling, cinema-ready entertainment. 2,000,000 first printing; Literary Guild main selection; film rights sold to Disney for a reported $8-$10 million; simultaneous large-print edition and Random House audio and CD editions. (Dec.) -- PUBLISHERS WEEKLY.