Adventurous Sailor Feared Dead After Being Washed Overboard : Tragedy: Father, who lives in Seal Beach, says son was trying to protect icebreaker moored in Punta Arenas, Chile.

An American adventurer whose family lives in Leisure World was presumed dead Tuesday after being washed off the deck of a ship in a fierce storm at the southern tip of Chile two days earlier.

Mark Eichenberger, 38, went overboard Sunday from the Erebus, a French-owned Antarctic icebreaker that was moored at Punta Arenas. The ship is chartered by the National Science Foundation to supply Palmer Station, an NSF post on the Antarctic Peninsula.

His father, Dr. Ralph Eichenberger, who moved recently from Huntington Beach to Leisure World in Seal Beach, said he believes that his son is dead and that his body might never be found because of the severity of the storm and fast-flowing currents.

When the storm moved in, Mark Eichenberger tried to protect the ship against damage by freeing it from its moorings, but a wave washed him into the harbor, his father said.

Eichenberger said his son was well aware of the storm dangers in Punta Arenas, having narrowly escaped such a storm while on his own 37-foot boat there two years ago.

Since boyhood, the victim yearned to see faraway places. He spent much of his childhood in the jungles of Peru with his parents, who were medical staff members with Huntington Beach-based Wycliffe Bible Translators.

His father recalled that when his son was 11, a friend gave him a crude boat shell for day sailing, but the boy had a bigger idea: He wanted to sail it down the Amazon and across the Caribbean to Miami. For years, he worked on the little vessel and, at age 17, achieved his dream, his father said.

Three years ago, Mark Eichenberger and three other men became the first to row from Chile to Antarctica, a journey chronicled in National Geographic magazine. In their 28-foot boat, they braved Drake Passage, considered to be one of the most dangerous stretches of water in the world, his father said.

Eichenberger said his son had hoped to return home soon and outfit a boat for his lifelong dream: circumnavigating the globe through the treacherous southernmost oceans.