Archaeologists exploring the ocean depths just off the coast of Oahu have discovered, intact, the sunken vessel that carried out a gripping rescue mission on December 7, 1941 — sailing into Pearl Harbor as the infamous attack unfolded, carrying British evacuees to safety — all with a Japanese submarine close on its tail.

Researchers from the University of Hawai’i and NOAA’s Office of National Marine Sanctuaries made the find while surveying waters about 32 kilometers off the coast, using sonar equipment and three-person submersibles.

The ship, originally built as the C.S. Dickenson and later commissioned as the U.S.S. Kailua, was in “remarkable” condition, the archaeologists said.

“Seeing the ship come into view, we were all amazed at its level of preservation — and by the fact that everything was more or less in place,” said Dr. James Delgado, director of NOAA’s Maritime Heritage Program, in a statement.

“The identification of the wreck was easy, not only because of its unique form, but also because the Navy’s identification number of IX-71 was still painted on the bow.” [Read about another recent maritime discovery: “Shipwrecks Discovered in Nautical ‘Graveyard’ at San Francisco’s Golden Gate“]

Launched in 1923 for the Commercial Pacific Cable Company, the Dickenson spent most of its years taking part in the gargantuan feat of engineering that linked the islands of the Pacific by underwater communications cable, making repairs and ferrying equipment to stations on distant atolls like Midway and Fanning Island.

With the advent of war in the Pacific, the Dickenson was chartered by the U.S. Navy in May 1942 and re-commissioned as the Kailua IX-71.

It was put to work laying cables and maintaining anti-submarine nets in New Guinea and Oahu.

The Kailua survived the war without damage, only to be decommissioned in the fall of 1945 and then intentionally sunk, as a target in a torpedo range, in February 1946.

“One of our first views of the USS Kailua was the classic helms wheel on the fantail,” said Hawaii’s Terry Kerby, who piloted the submersible that made the find.

“The ship was surprisingly intact for a vessel that was sunk with a torpedo. The upper deck structures from the bow to the stern were well-preserved and showed no sign of torpedo damage.”

Despite its long war service, it was the emergency rescue mission that the Dickenson conducted in December 1941 that gained fame for the vessel.

As tensions mounted all around the Pacific, British officials began to fear for the safety of civilian workers who staffed the communications station at Fanning Island, now known as Tabuaeran.

Though just a private communications ship, the Dickenson was chartered to collect the evacuees and take them to Hawaii.

On Dec. 7, 1941, it sailed into Pearl Harbor as the attack began, and evacuees on deck reported seeing a Japanese “midget submarine” tailing the ship as it neared the port, before U.S. ships ran it off.

Nari Strange, a Briton whose family was aboard the ship, recalled: “The crew and passengers on the Dickenson were watching the events, wondering if the U.S. Air Force was being too enthusiastic in their bombing practices, and they were quite annoyed initially.

“It was then realised that the planes were Japanese, but the little ship made it to a wharf, and I have a record of how the usual formalities were abandoned in order to get the crew and passengers safely ashore. ”

Dr. Hans Van Tilburg of the National Maritime Heritage Program said the vessel’s service before, during, and after the war make it a uniquely important artifact from the early 20th century.

“From her interisland service to her role in Pacific communications and then World War II, Dickenson today is like a museum exhibit resting in the darkness, reminding us of these specific elements of Pacific history,” he said.

There are no plans to recover or further study the ship, the team said. Instead, scientists are undertaking an effort to have its resting place commemorated as a historic site. [See another unusual find in Hawaii: “Monster Surf Exposes Rare Petroglyphs in Hawaii“]

“We plan to nominate the wreck to the National Register of Historic Places,” Delgado said.

“This unique American ship, vital in its role in keeping global telecommunications open in the first part of the 20th century, is also linked to historically significant Midway Atoll National Wildlife Refuge. …

“Wrecks such as this remind us of special places in the ocean, like the monument, that connect all of us to them as refuges, sanctuaries and museums beneath the sea.”