JET FROM LAX PLUNGES INTO ATLANTIC; 217 LOST; NO DISTRESS CALL RECEIVED; BODY FOUND.

Byline: Robert D. McFadden The New York Times

An Egyptian jetliner bound from New York to Cairo overnight with 217 people aboard plunged suddenly into the Atlantic Ocean south of Nantucket Island 33 minutes after takeoff early Sunday. One body and some debris but no survivors were found in a massive search, and the disaster's cause was not immediately known.

The aircraft - EgyptAir Flight 990, a twin-engine, wide-bodied Boeing 767-300 carrying 199 passengers and 18 crew members - had originated from Los Angeles. It left Kennedy Airport at 1:19 a.m. EST on a scheduled 11-hour nonstop flight to the Middle East. While takeoff was late, everything seemed normal.

But at 1:50, with the plane cruising at 33,000 feet in a clear night sky lighted by a half moon, something went terribly wrong, and the aircraft went into a plummeting, out-of-control dive. There was no distress call from the cockpit, the last voice contact with ground controllers having been routine. Two minutes later, the plane vanished from radar screens.

It was unclear what happened: whether an explosion had erupted, whether some mechanical failure had occurred, or even whether the aircraft was in one piece as it went down, aviation officials said. What was known was that the jetliner, without warning, plunged out of the sky and into the dark, rolling sea about 60 miles southeast of the Massachusetts island of Nantucket.

Federal officials said that radar sweeps at 12-second intervals showed that the aircraft fell from 33,000 feet to 19,100 feet - a drop of 13,900 feet - in 36 seconds, indicating that it was falling ``like a rock,'' as one aviation expert put it. The rate of descent was more than 23,000 feet per minute, while a normal descent is 1,500 to 2,000 feet a minute.

Even if the plane was still intact as it fell, aviation experts said, the high-speed impact with the water would have shattered it, and the chance that anyone survived was small. The water was a chilly 59 degrees, and 250 to 270 feet deep, a cod and tuna ground that would have been dotted with fishing boats and lobstermen in early October but was all but deserted early Sunday.

Coast Guard rescue ships swarmed to the scene, followed by helicopters and reconnaissance planes. As dawn broke, one body and a flotsam of wreckage - none with burn marks that might have suggested an explosion - were found adrift in the choppy sea. Throughout the day, officials insisted that they were still seeking survivors, but the grim search seemed all but hopeless.

``I want to re-emphasize our focus, and that is a continued effort to find victims who may still be alive,'' Rear Adm. Richard Larrabee of the Coast Guard said at a late-afternoon news conference in Boston. ``This is still a search-and-rescue case, and we are very mindful of the families, the trauma they are going through, and making every effort to keep them informed.''

Meantime, federal investigators began what was sure to be a long inquiry into a catastrophe that was hauntingly reminiscent of the fate of Trans World Airlines Flight 800, which took off from Kennedy Airport on a calm July evening in 1996, climbed out over the sea south of Long Island, N.Y., and exploded in midair, also without warning, killing all 230 people aboard. A bomb was long suspected, but officials now believe a fuel tank in the fuselage accidentally blew up.

There were no indications that the EgyptAir plane had been sabotaged and no claims of responsibility made by terrorists, American and Egyptian officials said, although the Federal Aviation Administration had warned airlines a month ago of a threat to bomb an unspecified flight out of Los Angeles or New York. EgyptAir Flight 990 had originated in Los Angeles on Saturday.

Weather conditions did not appear to be a factor. Fog had shrouded Kennedy Airport at the time of takeoff and through much of the day Sunday, but there

were no storms in the vicinity of the crash, winds were light and visibility was 10 miles or more, according to meteorologists.

It was equally unclear whether some mechanical failure on the 10-year-old jet, which had no history of major problems, or a human error had contributed to the disaster, which ranked with a score of crashes as being among the worst in aviation history. It was the first crash in the 67-year history of EgyptAir, a state-run airline that has 38 planes and flies to 85 cities around the world.

By daylight, four and a half hours after the crash, a small armada of Coast Guard ships and planes were on station, methodically searching a 36-square-mile region of ocean. Among their first discoveries were a body and wreckage - seats, seat cushions, a wheel, clothing, life jackets, passports, two partly inflated yellow life rafts and other small items that were not identifiable.

Through the day, five Coast Guard cutters and as many as 11 helicopters and airplanes joined the search, tracing routes worked out by computer to maximize efficiency. Wreckage and bodies were to be brought to the U.S. Naval Base in Newport, R.I., for identification.

A primary focus of the search was the wreckage of the plane itself, and its black boxes - the flight data and cockpit voice recorders - which hold a range of information, from speed and altitude to the talk of pilots, and could prove invaluable in the inquiry. The boxes have pingers that signal their location, but equipment to detect the pings was not expected to be available until Monday.

Darkness forced the planes back to their bases Sunday night, but the ships planned to continue their search for survivors through the night, and full operations were to be resumed Monday. The USS Grapple, the Norfolk, Va.-based Navy ship used to locate John F. Kennedy Jr.'s doomed plane last July, was expected to join the search Monday.

Since the aircraft fell in international waters, Egyptian officials might have taken charge, but they authorized the United States on Sunday to conduct the many-sided investigation, which was expected to unfold in New York, Cairo, Los Angeles and Newark, N.J. - all points where the plane had landed over the weekend - as well as in Boston, Newport, R.I., and Nantucket, where search-and-rescue operations were being coordinated.

Meantime, grieving families and friends of the crash victims gathered in Los Angeles, New York and Cairo to await news from airline officials and to meet with chaplains and other counselors. Many were sobbing in desperation over the loss of loved ones, while others were angry or in denial, unable to make sense of a tragedy that seemed to have no explanation.

CAPTION(S):

3 Photos, 3 Maps, Box

Photo: (1--Color) Nantucket police officer Anthony Santoro calls in a report of debris spotted off the island's coast.

Stephen Rose/Boston Globe

(2--Color) An unidentified family member of a passenger on EgyptAir Flight 990, right, is comforted at JFK International Airport in New York.

Ron Frehm/Associated Press

(3--Color) no caption (Grief-stricken family members)

Enric Masti/Associated Press

(1--3) Map/Box: AIRLINER CRASH AT SEA

An EgyptAir plane plummeted while heading from New York to Cairo on a flight that originated in Los Angeles. The search for debris was focused in an area about 60 miles south of Nantucket.

SOURCE: U.S. Coast Guard, NTSB, FAA, EgyptAir, LAX, Jane's All the World's Aircraft, Boeing, Associated Press, Knight Ridder Tribune Graphics Network.