THINGS HAPPEN, sometimes, that make the most earnest student long to cancel her higher intellectual functions. When the seasonal barrage of exams loom, and the voracious maw of the terminal room threatens, high art loses its appeal. Now is the time for Airplane II.

If you liked Airplane, here's your chance to get more of the same. If you didn't deign to attend a film so sophomoric, so silly, drop the pretensions and try this one; you may be pleasantly surprised. The movie's mainstay is its rapid-fire humor, and, even if only half the jokes hit theme, the film contains enough solid gags to have you laughing throughout the hour and a half show.

As with the first movie, Airplane II's plot seems purely incidental: The saga continues as Ted the pilot (Robert Hayes) and Elaine (Julie Hagarty), now a computer operator, maintain their love for one another despite adversity. Lloyd Bridges, Peter Graves and several others from the original provide the pilots and ground control technicians necessary to foul up the flight and embody running jokes. But placed in the nebulous future, this year's doom-bent flight takes places aboard a computer-controlled lunar shuttle, with a bow to 2001: A Space Odyssey.

Ken Finkelman, writer and director, seems to specialize in sequels. His previous credits include Grease II; he had nothing to do with Airplane. Not credited as writers, although responsible for major revisions, are Mike Reiss '81 and Al Jean '81. No strangers to humor, these two, Reiss served as the Harvard Lampoon's president, and Al Jean was his Ibis, or second-in-command. Anyone who remembers Reiss's Ivy Oration in '81 will recognize the brand of rapid-fire humor that makes this spoof spunky, and Jean's specialty of "over-kill" humor fits perfectly into a film that can show Mission Control deciding that the crew are "goners," and flash to a shot of the cockpit, where the Grim Reaper stands behind the pilot.

Like the Lampoon, this film proves strongest when it parodies; tired gags about drinking problems and translated "jive talk" fall flat. Airplane II contains some wonderful word play, and Finkelman's salutes to the television classics of the '60s and '70s cannot fail to touch those of us who grew up with Mission Impossible and Jeopardy. Nor is the rest of today's popular culture forgotten: Star Wars-types titles and the Battlestar Galactica theme begin this film and, within minutes, E.T. appears in a pay phone booth. Those not in the eighteen to thirty age bracket will miss these reverential spoofs, but the puns and wordplay should be universally accessible. Three officers, names Over, Under and Done, involve themselves in the obvious ranking problems: was Under Over, or was Under over Done? And there are boundless throw-away lines: Ted is praised as "the real boss, the top banana, the head cheese."

JULIE HAGARTY played a similar character to Elaine in Woody Allen's mediocre "A Midsummer Night's Sex Comedy," but she seems to have lost some versatility, Granted, this script does not call for a wide emotional range, but surely the woman can do something besides act perplexed and frightened. Borderline hysteria can be mildly tiring. Hayes's Ted, with matinee-idol looks, seems to have a better grasp on his character's emotional range. But in a film like this, great acting is not of the essence. The cast provides sufficient body for the swift and silly script; they don't need to do much more. After all, Airplane II is not great deathless, sorry Mike and Al. But what a nice break from your thesis.