When Ernest Lehman was writing the screenplay for "Black Sunday," the 1977 movie about an airborne terrorist attack on the Super Bowl, the very idea seemed preposterous. Many critics agreed.

Now, with Saddam Hussein hurling threats across the ocean and Super Bowl XXV officials laying on the heaviest security ever, the idea seems a trifle more serious -- serious enough for Washington's ABC television affiliate, WJLA, to have scratched "Black Sunday" from its Sunday early-morning lineup.

"Good for them," Lehman said yesterday.

A spokeswoman for WJLA, Jane Cohen, said that the movie had been scheduled months ago for the 1:45 a.m. slot; ABC television is carrying the Super Bowl broadcast later that day. But because of "the situation in the Middle East," she said, the affiliate decided to replace "Black Sunday" with "Fire on the Mountain," a 1981 Buddy Ebsen picture.

New York City's independent station WPIX-Channel 11 also announced this week that it would drop "Black Sunday" from its Saturday afternoon schedule, according to a report in the Daily News.

In the film, based on Thomas Harris's 1975 novel, Bruce Dern plays a deranged Vietnam veteran in cahoots with the Palestinian terrorist group Black September. On Super Bowl Sunday, he commandeers the Goodyear blimp and flies it over the Orange Bowl and thousands of cheering fans, including the president of the United States, planning to unleash 200,000 rifle darts on the hapless crowd. The plot -- the terrorist plot -- is foiled by an Israeli commando, played by the late Robert Shaw.

Lehman, one of three screenwriters responsible for Paramount Pictures' version of "Black Sunday," said, "Paramount and the networks and cable have shown admirable restraint, to coin a phrase, in not exploiting the picture at all in the past week. ... Who the hell needs that movie to come on and give anybody any ideas?"

In that case, he was asked, why write such a movie at all?

"The plot of 'Black Sunday,' " Lehman said, "seemed so far-fetched -- the idea of taking over a Goodyear blimp -- I don't think any of us felt we were giving anybody any ideas."

But "the world is becoming more violent, and there's no doubt that before the world became more violent the media -- movies and television -- showed a lot of people how to commit that violence. We all bear some responsibility, including me," said Lehman, whose other screen credits include "North by Northwest," "West Side Story," and "The Sound of Music."

Book author Harris, whose more recent novel "The Silence of the Lambs" is about to be released in a film version, yesterday passed word through his literary agent that he would not comment on "Black Sunday," his first book. Harris, who worked for the Associated Press for years before turning to a lucrative novel-writing career, is notoriously reluctant to speak to the news media.

Odd as it may seem today, the National Football League cooperated in the production of "Black Sunday," which incorporated actual footage of Super Bowl X.