Nervously suspenseful and properly infuriating, "The Taking of Flight 847: The Uli Derickson Story" dramatizes the brave role played by a TWA purser in a tragic and notorious 1985 plane hijacking. The NBC film airs at 9 tonight on Channel 4.

Some viewers may prefer the Chuck Norris approach to this kind of story ("Delta Force"), which is to fictionalize it and give it a relatively happy ending, with the terrorists blown to bits for their sins. NBC's film must stick more closely to the lamentable facts.

Robert Dean Stethem, a U.S. Navy diver played in the film by Steven Eckholdt, was viciously beaten and then murdered by the terrorists. That is one of the facts. The terrorists got away; that is another. The film has an unsatisfying ending because the whole horrible incident did.

By concentrating on the positive efforts of Derickson, who is believed to have prevented at least one other murder, the film has a purpose other than to make one's blood boil. Lindsay Wagner, though encumbered with a strangely straggly, wet-noodle hairdo, does a conscientious and credible job playing Derickson. The other flight attendants are all but invisible as the story is told here.

Much of Derickson's time was spent as an interpreter; the two hijackers spoke no English, but one, like Derickson, spoke German. In the film, she is also shown helping one passenger pass a note to another (the content of which we are never told), persuading the terrorists to release women and children during one of the plane's stops and trying to prevent efforts by the Shiite hijackers to identify those among the passengers who were Jewish.

Immediately after the hijacking, Derickson faced muttered charges that she had given in to the terrorist demands for Jewish names. She denied the accusation. The film, written by Norman Morrill, has her saying "I can't do that" when directed by a hijacker to identify Jews from their passports. Derickson served as a consultant to the producers.

After seven hours of the ordeal and roughly one of the film, an attempt is made to humanize the terrorists, who are brilliantly and chillingly played by Eli Danker and Joseph Nasser. The leader says his wife and child were killed when the U.S.S. New Jersey shelled Beirut. He asks Derickson to sing a German nursery tune.

His partner proposes marriage to Derickson. Later she holds one of the terrorist's guns but does not shoot him. "You save lives better than you take lives," he tells her. How faithful these scenes are to what really happened we will never know. Generally speaking, it is probably better not to humanize terrorists. They surrender the right to a point of view when they terrorize.

Director Paul Wendkos, who could do this kind of film in his sleep, clearly did not; the mood is rigorously tense. Some of the earliest blows that the terrorists give to the flight crew, however, are shot so as to look almost like the bops and whacks of Larry, Moe and Curly. That the two men are lethal becomes clear soon enough.

"The Uli Derickson Story" was executive-produced by former White House photographer David Hume Kennerly and former Newsweek reporter Jim Calio. Often such TV movies seem exploitive and crass. This one does not.