During World War II, the Japanese developed a sophisticated submarine technology, one that had they been able to fully deploy before the war ended, might well have made a dent in American forces. On Tuesday, November 17, 2009, National Geographic Expedition Week takes us to the island of Oahu in Hawai'i. There, Terry Kerby and Max Cremer of the Hawai'i Undersea Research Laboratory (HURL) at the University of Hawai'i have been searching for imperial Japanese submarines known to have been scuttled off Oahu by the U.S. Navy in 1946.
Five submarines are known to have been scuttled off Oahu; and Kerby and Cremer have discovered four of the wrecks to date. Two types of subs were brought to Oahu and studied at the end of the war: the I-400 class and the I-200 class. The I-400 class, represented by the I-14, I-401 and I-400, were each 400 feet long, and carried 18 21" torpedoes, a fifty-caliber deck gun and up to three Aichi M6A1 Seiran seaplane bombers that could be launched from underwater. Each of those bombers could carry either an aerial torpedo or bomb weighing nearly 1,800 pounds. The I-400 class submarine had a range of 37,500 miles at 14 knots, and could go one and a half times around the world without refueling.
The I-200 class, represented by the I-201 and I-203, are known as the "fast attack subs", which were specially designed to travel as quickly and silently as possible. It was capable of underwater speeds of up to 20 knots, among the fastest of diesel submarines ever made. Most of the Japanese subs used a rubberized outer coating to make it harder for sonar or radar to find it.
The five subs were surrendered to American forces at the end of World War II, and then brought to Hawai'i to be studied. After a year or so of study, the submarines were scuttled, purposefully sunk off Oahu beach, according to the video, to keep the technology out of the hands of the Russians.
HURL and WWII Submarines
The Hawai'i Undersea Research Laboratories (HURL) found one of the submarines in 2005; in February 2009, with the help of some 16-mm film shot by sailor Charles Alger, they located another three submarines, and they are currently seeking the wreck of the fifth. The program shows the February investigations, as well as several CGIs of these amazing subs.
Experts appearing in this program include Kerby and Cremer of HURL; Hans Van Tilburg, a maritime heritage coordinator for NOAA's Office of National Marine Sanctuaries; and Dik Daso, curator of modern military aircraft at the Smithsonian. Veterans of WWII appearing include Buck Catlin, commander in the US Navy; Atsushi Asamura, squadron leader in the Imperial Japanese Navy and Seiran pilot; and Charles Alger, an American sailor whose 16-mm film of the 1946 scuttling of the submarines led to their discovery.