"We suddenly exploded, the whole ship seemed on fire. We couldn't breathe for the smoke, we couldn't see. Parts of the hull were white-hot."

That was the scene described by a survivor aboard the HMS Sheffield yesterday seconds after an Argentine missile hit the destroyer amidships, causing the first loss of a Royal Navy ship in warfare since World War II. The ship was part of Britain's naval task force sent to the South Atlantic to recapture the Falkland Islands seized by Argentina more than a month ago.

The survivors told British television and press reporters aboard the Hermes, flagship of Britain's South Atlantic task force, harrowing tales of their five-hour fight to save the ship. Latest reports are that 30 of the 270-man crew are missing and feared dead and possibly another 57 are injured.

The Sheffield's skipper, Capt. Sam Salt, 42, who gave the order to abandon ship, said the French-made Exocet missile "had a devastating effect. It hit the center of the ship, the center of all operations--mechanical detection, weaponry.

"It came in at six feet above the water level, damaged two large compartments and, when inside the ship, exploded outwards and upwards.

"We only had time to say 'Take cover.' Three or four seconds later the missile hit, traveling at hundreds of miles an hour."

Within 20 seconds, he said, the center of the ship was filled with "black, acrid, pungent" smoke.

Indicating that some of the dead may have been trapped aboard the 4,100-ton Sheffield, the captain said, "We couldn't get below decks near the seat of the damage. We knew there were men down there, but we didn't know how many."

He told reporters that there was no pressure in the firehoses and lighting went out because of a massive loss of power from the ship's engines.

"We could feel the heat of the deck through our shoes," said Salt, the son of a submarine commander killed in World War II. "The superstructure was steaming, paint on the ship's side was peeling off. The area where the missile penetrated the hull was white-hot."

Explaining why he ordered the crew to abandon ship after struggling for five hours against the raging fires, Salt said, "We started thinking that we were on a losing wicket when we realized that the fire was spreading."

The flames were also getting close to the ship's ammunition and fuel supplies, he added. "Unfortunately, we were losing, not winning."

In addition, the Sheffield, christened by Queen Elizabeth a decade ago as the first of a new class of British destroyer, was diverting the efforts of other warships in the task force "when they were under the threat of attack," Salt said.

Reporters who watched from the Hermes and the aircraft carrier Invincible, 15 miles away, said most of the Sheffield's crew escaped to an unidentified task force ship that went alongside. Others were picked up by helicopters and some went over the side of the ship into the icy South Atlantic waters.

Survivors on the Hermes, who have lost all their possessions, are sleeping on camp beds and mattresses. Seamen suffering burns and severe shock were carried aboard on stretchers.

Later Salt flew back aboard his ship by helicopter and found that "the whole of the working area of the ship was a roaring mass of flames. We could see right down into the engine room."

A reporter on the Invincible said the Sheffield was "completely blotted out by smoke which formed a solid column from the sea to the clouds."