A Piedmont Airlines flight from in New York to Washington was caught in the edge of the violent thunderstorm that struck the Washington area Friday and the pilot said the plane abruptly plunged 2,000 feet before he managed to pull it out of its sudden descent.

Capt. Walter Downey said Flight 33 was not advised of the turbulence as it apprroached Dulles International Airport and tried to beat the storm to the airport.

Two of the plane's approximately 50 passengers said books, people and blankets were adrift in the plane when the pilot suddenly pulled out of the plunge.

"It was the most incredible thing, I was scared to death," said Vicki Ahlert. "My husband was lifted out of his seat."

Another passenger, Joel Chaseman, president of Post-Newsweek Stations Inc., said he could not see anything but a greenish-black cloud out of his window as the pilot fought to control the plane.

"We were being tossed around pretty good," Chaseman said "I couldn't believe we were going to land."

"There were three possibilities: he could get lucky crash, or turn up his nose and get the hell out of there," Chaseman said. "He pulled up and as the plane changed direction everybody raised out of their seats and everything in the cabin began flying around as if they were weightless."

During the two-hour storm Friday evening, 86 flights leaving National Airport and four flights leaving Dulles were delayed more than 30 minutes.

Eight planes were late arriving at National but none was late in coming into Dulles although aid controllers said at least three flights were diverted to other airports.

Manuel Vaamonde, assistant chief in the Dulles control tower when the Piedmont field attempted to land, said the pilot had been informed that a storm was in the area.

"He tried to make a visual landing," said Vaamonde, "and the storm just came up. He made a left turn and abandoned the approach. He was trying to beat the storm."

A spokesman for the National Transportation Safety Board said turbulence around thunderstorms, called "cloud roll," is sometimes not apparent to pilots because it can be as far as 10 miles away from the storm.

"They (the controllers) can spot the storm for you," he said, "but sometimes you will have trouble even though you know where the storm is and can pinpoint it on your radar (in the plane).

According to Chaseman, after the plane pulled out of its descent the pilot came on the address system and apologized for what had happened.

"No one advised me of any turbulence as I was approaching," said Downey. "I was hoping to get in before the storm. I assume they didn't know about the turbulence out there. I had gone all the way to Frederick, Maryland, to try and avoid any problem with the storm . . . I didn't think there would be any turbulence."

Downey said he knew of the storm before his plane left LaGuardia Airport and sighted the storm on the radar on his cockpit control panel.But he said the problem started when the plane was still beyond the storm.

"If I had continued the approach and tried to land it is possible there would have been an accident," Downey said.

Downey said a clipboard flew past his head as he recovered control of the plane and halted its descent. He said he knew objects were flying around the plane's cabin but that his hostess did not inform him that the passengers were screaming as Chaseman and Ahlert reported.