Cold War Era Begins In Hawaii In 1946 With Giant I-400 Japanese Submarines
Sunk Off NAS Barbers Point
by John Bond
Pacific Cold War Patrol Museum To Feature Hawaii Undersea Research Laboratory Discovery of I-400 Class Japanese Submarines Sunk Off Barbers Point
If one were to place an historic marker on when the Cold War began in Hawaii, if not in the Pacific, one has to look no further than the sinking of the giant I-400 Japanese submarines captured at the end of WW-II. Bound by an agreement to share any discoveries with the Soviets but feeling the pressure of the looming cold war, it was a calculated decision to keep the technology out of Soviet hands.
With missions to use biological weapons to attack U.S. cities and blow up the Panama Canal, the aircraft carrier submarines had the potential to change the course of the war in the Pacific.
But fortunately for America, it’s secret weapon – the atom bomb, was put into action first.
They were sunk in 1946 explicitly to keep them out of the hands of the Soviet Union. They were such an important technological leap forward, like the German V-2 rocket, that they had to be quickly studied and then sunk off NAS Barbers Point, which has become a mass undersea graveyard of
WW-II era ships and military equipment of all kinds.
H.I.J.M.S I-400 being sailed from Sasebo, Japan to Pearl Harbor Hawaii in 1945
under the US flag with a US Navy crew.
(H.I.J.M.S - His Imperial Japanese Majesty's Ship)
By 1945 these special submarines were being readied for attacks when the war ended.
On August 15th, Emperor Hirohito broadcast from the Imperial Palace his decree ending hostilities.
The I-boat crews were thunderstruck. The shattered group commander reluctantly carried out Tokyo's orders and returned on the surface to their home port. Crews were ordered to jettison all documents and munitions, fire all torpedoes, and catapult all aircraft into the sea.
The huge I-Boats were intercepted east of Honshu on August 28th and taken over by the U.S. Navy.
Special crews learned how to operate the large submarines and also acquired while in the IJN Sasebo home port a number of advanced Japanese torpedoes which were far more effective than Navy torpedoes at that time. The technological leap forward was not going to be allowed to fall in Soviet navy hands and many captured Japanese submarines were later scuttled off shore.
The I-400 was decades ahead of her time. She was the world's largest submarine, with a length of 400 feet and a surfaced displacement of 3,530 tons. Her main deck was 115 foot long with a 12 foot diameter hangar housing three torpedo-bombers. These floatplanes were rolled out through a massive hydraulic door onto an 85 foot pneumatic catapult, where they were rigged for flight, fueled, armed, launched, and, after landing alongside, lifted back aboard with a powerful hydraulic crane.
The I-400 was equipped with a snorkel, radar, radar detectors, and fuel tanks that gave her a range of 37,500 miles- one and a half times around the world. She was armed with eight torpedo tubes, a 5.5 inch 50 caliber deck gun, a bridge 25mm antiaircraft gun, and three triple 25mm AA mounts atop her hangar. She also had a special hull coating that may have been the most technologically advanced of any submarine at that time.
The U.S. Navy had captured five Japanese I-400 class submarines — including the I-400 — and brought them to Pearl Harbor for inspection. Then after a high level Navy conference orders were given to sink the submarines off the coast of Oahu when the Soviet Union demanded access to them. The Cold War was just beginning, and the U.S. didn’t want the submarine technology in the hands of the Soviet Union.
TIME LINE OF I-400's IN HAWAII
"Orders are being issued to dispose of all Japanese submarines by sinking. Those in Japan will be sunk at once, those in Pearl Harbor when authorized and at the discretion of CinCPAC dispose of all captured Japanese submarines by sinking."
4 June 1946 The I-400 class submarines were scuttled in the waters off Barbers Point by torpedoes from US Navy submarine USS Trumpetfish to prevent their advanced technology from being made available to the Soviets.
Hawaii Undersea Research Laboratory finds the historic huge I-400 submarine
The Hawaii Undersea Research Laboratory's (HURL) deep-diving submersible Pisces V located the wreck of I-400 while investigating targets of interest previously identified by Terry Kerby, Steve Price and Chris Kelley of HURL. Pisces V’s crew included submersible pilot Terry Kerby of HURL and Drs. James Delgado and Hans Van Tilburg of the National Oceanic and Atmospheric Administration’s (NOAA) Maritime Heritage Program.
"The I-400 has been on our ‘to-find’ list for some time. It was the first of its kind of only three built, so it is a unique and very historic submarine," said Kerby.
"These historic properties in the Hawaiian Islands recall the critical events and sacrifices of World War II in the Pacific, a period which greatly affected both Japan and the United States and shaped the Pacific region as we now know it," said (Hans) Van Tilburg, maritime heritage coordinator for NOAA in the Pacific Islands region.
The I-400 was the largest submarine ever built until the introduction of nuclear-powered submarines in the 1960s. Unlike any other diesel-electric submarine to this day, it could travel a range of 37,500 miles — one and a half times around the world — without refueling, according to the UH press release. The innovative submarine could hold up to three folding-wing float-plane bombers, each with a 1,800-pound bomb, that could be catapulted off within minutes after surfacing.
Giant World War II aircraft-carrying submarine discovered off Oahu coast
I-400: Largest diesel submarine ever built, found off of Barbers Point, Aug 2013.
HURL Gallery: Highlight Photos: 2009 Mission Photos
Featuring the I-14, I-201, I-401, a 3-piece midget sub
A history documentary was made about these submarines and can be viewed here:
A detailed account of the I-400 capture is here:
Barbers Point A Mass Graveyard Of WW-II Sunken Subs, Ships And Military Equipment
USS New York (BB-34) sunk as target on July 8, 1948, off Barbers Point after an eight-hour pounding by ships and planes using bombs and gunfire in full-scale maneuvers with new torpedoes.
USS Nevada (BB-36) sunk as target off Barbers Point, HI, July 31, 1948
The Barbers Point seafloor is littered with weapons, trucks, tanks and aircraft of all kinds.
Pacific Cold War Patrol Museum for Facility 972 - Barbers Point, Ewa-Kapolei, Hawaii