Action Fans Feel Patriotic : Movies: ‘Patriot Games’ knocks ‘Lethal Weapon 3’ from top spot. A record-tying summer box office is seen possible.

Harrison Ford and the espionage thriller “Patriot Games” powered box-office grosses to a fourth consecutive big weekend, and some film industry observers predict that this summer may equal or actually exceed the record summer of 1989, when the original “Batman” was released.

“Patriot Games” provided the audience for action movies with a fresh attraction in a market that has been dominated lately by “Lethal Weapon 3” and, to a lesser extent, “Alien 3,” both of which have peaked at the box office.

Barry London, president of Paramount Pictures motion picture group and worldwide distribution, said Ford’s all-around appeal as the heroic former CIA analyst Jack Ryan, and the film’s emphasis on keeping a family together were among the reasons for its popularity. “We’re ecstatic with the movie’s performance,” he said, citing the film’s $18.5 million gross for its first Friday-Sunday period.

Although “Patriot Games” didn’t quite score the $20 million Paramount estimated on Sunday that it would do, the movie’s debut was the year’s second-biggest, trailing only the $33.4 million grossed by “Lethal Weapon 3” on the May 15 weekend.

“With these kinds of broadly popular movies, theater owners are saying they don’t see how this summer can fail. It could even equal 1989,” said John Krier of Exhibitor Relations Co., a firm that tracks box-office grosses.

Over the weekend, “Lethal Weapon 3,” starring Mel Gibson and Danny Glover, surpassed the $100-million mark, the third 1992 release to achieve that box-office distinction, following “Wayne’s World” and “Basic Instinct.” But the police-action film hit the mark on Saturday, its 23rd day in release and at a much faster pace than the other two.

For the weekend, “Lethal Weapon 3” sold $9 million worth of tickets, to land in third place, after three consecutive weeks in first.

In second place for a second weekend was the Whoopi Goldberg comedy “Sister Act,” with the offbeat actress playing a singing nun. The $15-million Disney/Touchstone Pictures production scored $11.4 million for the weekend and brought its cumulative gross to $28 million. As an indication of favorable audience word-of-mouth, “Sister Act” grosses only dropped about 4% from the first weekend; it was playing on about 300 more screens, but the drop in business is considered insignificant by industry standards.

By contrast, business for the romantic and historical epic, “Far and Away,” starring Tom Cruise, fell by about 25%, a figure that distributor Universal Pictures had hoped to avoid by adding 200 more screens in an effort to boost sagging grosses.

Tom Pollock, chairman of the MCA Motion Picture Group, the parent of Universal, last week said he hoped the movie might find a market niche that would allow it to continue in theaters all summer. He said he was looking for a box-office drop-off of no more than 20%. With the lower grosses, there may be growing pressure on theater exhibitors to pull it in favor of fresher and potentially bigger moneymaking movies due out.

In fifth place was the $7-million Disney/Hollywood Pictures release “Encino Man,” trailed in sixth by “Alien 3,” the 20th Century Fox sequel. “Alien 3” took a substantial 50% drop in business from the previous weekend, as its grosses have declined from its smash opening on the Memorial Day weekend. Still, with an estimated $42 million in grosses so far, the $40-million film should make money for the studio in overseas and video markets.

Back on the chart was the Christmas season sleeper hit “Fried Green Tomatoes,” boosted by the addition of more than 450 screens in discount houses. The movie has cooked up more than $76 million to date.