(Note:In October 1962, during the Cuban Missile crisis, Mount McKinley served as flagship for ComPhibLant and ComPhibGru 4.)

By ABCNEWS - Saturday, Oct. 27, 1962 was the most dangerous day of what may have been the most dangerous week in American history.

"Bad news kept streaming in during the day," said Ted Sorensen, a member of President John F. Kennedy's crisis team. "The worst news was that our U2 high flying reconnaissance plane for Cuba had been shot down."

Gen. Maxwell Taylor and the Joint Chiefs of Staff urged an all-out attack on Cuba, but Kennedy resisted the pressure.

No one in the Cabinet Room knew that, at the same time, U.S. destroyers were playing a perilous cat and mouse game with a Soviet submarine, Sub B-59, heading towards Cuba.

Documents released today by the National Security Archive confirm that late that Saturday afternoon, the USS Beale and the USS Cony lobbed 10 concussive grenades at Sub B-59. The American crew was unaware of the Soviet's secret payload.

"It felt like you were sitting in an empty barrel and somebody's constantly beating it with a stick," said Vadim Orlov, an intelligence officer aboard Sub B-59.

The American crew was unaware that the Soviet sub was carrying nuclear weapons.

"I don't think we even speculated that they were nuclear armed because our ships were not," said Capt. John Peterson, who was deck officer on the USS Beale.

Grenades Almost Triggered Nuclear Strike

The grenades were designed to scare the sub to surface. Instead, they almost triggered a nuclear strike. As Orlov recounts, his commander, Valentine Savitsky, lost his composure.

"The situation was becoming so difficult that Commander Savitzky was extremely stressed out and at one point decided to assemble the nuclear torpedo," Orlov told ABCNEWS. "When that order was given, we realized that if the nuclear weapons were used it would have meant death for every one of us."

And death for maybe millions more. U.S. war plans called for a nuclear response to any nuclear strike and official documents also released today reveal that the Pentagon already had depth charges on Guantanamo that were ready to be armed with nuclear warheads.

"Both sides would have gone up that nuclear ladder of escalation very quickly and very soon there would be nothing left," said Sorensen.

Cooler heads prevailed and the nuclear torpedo was disarmed. "Commander Savitsky just calmed down," said Orlov.

That gave President Kennedy time to send his brother, Attorney General Robert Kennedy, to Russian Ambassador Anatoly Dobrinyn with a secret deal for Khrushchev: If Soviet missiles were removed from Cuba, U.S. missiles would later be removed from Turkey.

Sunday morning, Radio Moscow reported that Khrushchev would dismantle the missiles. And President Kennedy went to church.

There were no landings in Cuba that October, but Amphibious AGC's have participated in all aspects of landings around the world throughout troubled times. We've found written details about one such landing in World War II in the pacific where AGC's directed the fighter planes involved. Read about a CIC (Combat Information Center) Operation in an AGC during the landings at Iwo Jima.... the story mentions the Eldorado and the Auburn, two of our sister ships.