First the Grand Scene was rewritten. Then the curtain dropped on Act III. Now the Kennedy Center has hired a new cast for its longest running flop, the restaurant complex. New York Restaurant Associates has signed for a long run, a 10-year contract with a five-year option, to operate the Center's three restaurants, employe cafeteria, hors d'oeuvres bar and catering. Restaurant Associates' major credits in New York include restaurants in Lincoln Center, Rockefeller Center, the Metropolitan Museum, the Ford Foundation, the Tower Suite and Mama Leone's; its only other Washington appearance was at the Capital Hill Club, the Republican club that is now being run in-house.

Canteen Corporation of Chicago, a subsidiary of TWA, is out at the Kennedy Center, with two years left to run on its 10-year contract. The divorce, said the Center's director of operations, Tom Kendrick, was mutually agreeable. The storm clouds had long been gathering. In 1971 the restaurants, then called the Promenade cafeteria, the Gallery cafe and La Grand Scene haute cuisine restaurant, opened to national publicity and acclaim for the $1.25 million kitchen and dining facilities. The kitchen could prepare main courses for 800 people in 45 minutes, cook up to 90 filets of beef at a time. But it could not keep its first general manager more than three days. He was fired, with one of the issue reported to have been whether the French menus included English translations. And it could not keep the public happy with road-show food at Broadway prices.

By February 1978, Kennedy Center Chairman Roger Stevens was publicly saying he was unhappy with the quality of the Kennedy Center restaurants. The restaurants were then closed for repairs as the kitchen floor had defects that led to water leaking into the Concert Hall. The four months of repairs cost the Canteen Corporation customers. The reopening of the restaurants with new names (Act I, II and III) and ever-declining critical acceptance did them no further service.

In the meantime, in New York, Restaurant Associates had taken over the Lincoln Center's food concession. The ascending quality and revenue of the Lincoln Center operation under Restaurant Associates impressed the Kennnedy Center board, as Lincoln Center's needs and problem closely paralleled those at the Kennedy Center.

The Kennedy Center brings 6,000 to 7,00 people a day within an elevator ride of the restaurants just for performances. The additional tourist influx brings the restaurants' passersby to 4 or 5 million a year. The bad news for the restaurants, though, is that the visitors generally want to eat in a hurry, and mostly at the same time.

The Kennedy Center, in looking into alternatives, favored Restaurant Associates' smaller size and more individual approach.

The contract was signed in May, and Restaurant Associated moved in July 16. "The fare improved 500 percent overnight," applauded Kendrick. Restaurant Associates immediately began to change the cafeteria and the deluxe restaurant operations as well as the employe cafeteria. Employes report notable improvements: More fresh fruits and vegetables, larger staff, higher quality food, greater variety, attractive presentation.

The public cafeteria, its name changed to Encore, started serving fresh foods with no convenience foods except in emergencies. Some prices have been reduced: main dishes are now $2.25 to $3. The menu changes daily, typically including as main dish osso bucco, sesame chicken or pot roast, with assorted pastries made by the new 24-year-old Swiss pastry chef. Chill is the biggest seller in the employe and public cafeterias.

The deluxe restaurant, now called the Roof Terrace (Roof Terrace Grill was vetoed by the Kennedy Center board as being suggestive of a neighborhood tavern), features appetizers the likes of leeks vinaigrette, timbales of salmon and sole and prosciutto with the newly trendy kiwi fruits. Main courses are simpler, mostly grilled meats and a few cold dishes such as veal tonnato and striped bass with dill. Main courses are $8.95 to $12.95. An eight-year issue has been resolved: the menus are entirely in English.

The major innovation in the new operation is an hors d'euvres bar off the Roof Terrace, where hot hors d'oeuvres (fried shrimp in ale batter, chicken brochettes in pineapple, for instance, at $3.25 to $3.95) will be serve from 5 p.m. to midnight. Late in the fall an after-theater supper will be offered in the main dining room. The management is looking for pianists and other entertainers for the Roof Terrace and bar.

The cafe, to he called the Curtain Call Cafe, is now closed for thorough cleaning. Although the restaurants, under the Canteen Corporation, were awarded a certificate of merit by the D.C. Environmental Health Administration on May 29, the new food services Paul Buck, emphasized, "One of our major concerns is cleaning up the operation completely."

A certificate of merit is awarded for scoring over 90 under the D.C. food sanitation inspection program for nine consecutive months.

"There are rodents. Lots of them," he added. "It is going to be very difficult to achieve a 93 rating based on what I have seen. It will take us months and months and months to get to any level where we can achieve a 93."

While Kendrick admits that there have been rodents recently, he attributes the problem to recent construction, a temporary influx. "They are not there now, and they weren't there before," he stated.

Neither Restaurant Associates nor the Kennedy Center has advertised the restaurants' change. They hope to shake down the operation, to build and train the service staff, before they undergo fresh scrutiny.