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HMC-FMF-PJ
11-13-2009, 06:32
http://www.csmonitor.com/2009/1113/p02s04-usgn.html

Japanese subs found off Hawaii could have changed World War II

The two Japanese submarines – which were commandeered and scuttled by the US after World War II – were much larger, faster, and stealthier than US subs of the day. One included a float-plane that could attack New York.

By Peter N. Spotts | Staff writer of The Christian Science Monitor, November 12, 2009 edition


Marine researchers have found a pair of Imperial Japanese Navy submarines on the sea floor off Hawaii's Oahu Island – vessels so advanced for their day they would provide plenty of fodder for a fresh novel by Tom Clancy.

Known by their vessel numbers, the I-14 was a 375-foot submarine aircraft carrier – its crew capable of assembling and launching two float-plane bombers in roughly 20 minutes. The other craft, the I-201, was an attack submarine, twice as fast as any in the US fleet and faster than subs in any other Navy during World War II.

"This is one of the most significant marine-heritage findings in recent years," according to Hans Van Tilburg, a marine archaeologist who is the maritime-heritage coordinator for the National Oceanic and Atmospheric Administration's National Marine Sanctuaries in the Pacific. The find was announced Thursday.

"These submarines are 60-year-old time capsules offering first-hand insight into a military technology that was far ahead of its time," he says. The subs were so advanced, Mr. Van Tilburg continues, that had they appeared earlier in the war and in larger numbers, "the submarines had the potential to turn the tide of war."

Among the approaches Japanese designers used: a rubbery coating on the outside of the hull and conning tower to absorb radar and reduce the likelihood that sonar aboard US destroyers or subs would pick up sounds from inside the Japanese vessels.

At 400 feet long, the I-400 subs were designed to travel 37,500 miles without refueling – enough range to cruise around the world 1-1/2 times between fill-ups and have enough fuel left for their three aircraft. Intended targets for the subs' bombers included Washington and New York. None of these long-range missions were carried out.

The expedition was conducted using manned submersibles operated by the Hawaii Undersea Research Laboratory, a cooperative venture between NOAA and the University of Hawaii. Partial funding for the effort came from the National Geographic Society's cable TV arm, the National Geographic Channel.

Today's announcement comes four and a half years after the same submersible team spotted the remains of one of the largest subs, the I-401 off the Hawaiian Islands.

The I-401, along with the I-14 and I-201, were captured at war's end and sailed to Hawaii, where US naval intelligence officers could plumb the ships' secrets. They are three of five advanced Japanese subs the US sailed to Pearl Harbor after the war. All were scuttled to avoid having to share the information with the Pacific war's late-comer and co-claimant to such prizes, the former Soviet Union.

HMC-FMF-PJ
01-05-2010, 01:06
PBS NOVA: Killer Subs in Pearl Harbor
Dive beneath the surface to discover an untold story of WWII.
http://www.pbs.org/wgbh/nova/killersubs/

Tuesday, January 5 at 8 pm

Check local listings: http://www.pbs.org/wgbh/nova/schedule-local.html


NOVA dives beneath the waters of Pearl Harbor to trace provocative new clues to one of the most tragic events of World War II—the sinking of the USS Arizona. More than 1,000 crew members perished in the greatest single loss of life in United States naval history. For decades, it has been thought that a bomb dropped by a Japanese aircraft sank the Arizona. But the discovery of a group of Japanese midget subs in and around Pearl Harbor has raised questions about the battleship's final hours.

In this program, NOVA's team of expert investigators journey to the seafloor to explore the wreckage of the most mysterious of these subs. Did this mini-sub and its two-person crew make it into Pearl Harbor and fire torpedoes at the Arizona? NOVA pursues this puzzle with unprecedented access to the remains of the Arizona and other unique evidence, including aerial photos taken by Japanese aircraft and moving testimonials from U.S. and Japanese veterans. "Killer Subs in Pearl Harbor" is a gripping investigation of the possibility that these tiny but lethal mini-subs may have played a crucial and previously unsuspected part in the tragic events of that "Day of Infamy."


= = = = =

Here is the official line written back in 2000:

Japanese Type A Midget Submarines used in the attack on Pearl Harbor
http://www.history.navy.mil/photos/sh-fornv/japan/japtp-ss/mdg-a-2.htm

"One of the five Pearl Harbor midgets is still unaccounted for. Recent studies of Pearl Harbor attack photograpy have led some observers to argue that one of the midgets was in place off "Battleship Row" as the Japanese torpedo planes came in, and may have fired its torpedoes at USS Oklahoma (BB-37) or USS West Virginia (BB-48). This contention is still controversial, but, if it is true, the "missing" Type A midget submarine may lie undiscovered inside Pearl Harbor."


Here is what the New York Times said in Dec 1994:

Analysis Sees Submarine Role in Pearl Harbor
http://www.nytimes.com/1994/12/08/us/analysis-sees-submarine-role-in-pearl-harbor.html

"Historians have known for some time that the Japanese used five midget submarines in the attack. But until now, it was believed that none succeeded in attacking any ships, Mr. Martinez said.

Photographs taken by the crew of a Japanese torpedo bomber during the attack were analyzed at Mr. Martinez's request by Autometric Inc., a company in Alexandria, Va., that specializes in advanced photo imagery techniques.

The request was made after the recovery of a torpedo in Pearl Harbor in 1991 and the discovery about a year ago of aerial photographs of the harbor taken 10 days before the attack by the Army Corps of Engineers, Mr. Martinez said.

The analysis indicates that the Japanese photos were taken 6 to 8 minutes after the attack started at 7:55 A.M., said John Rodgaard, the leader of the Autometric team. "Our analysis confirms the presence of a submarine," he said.

The analysis, which included a close look at shock waves and convergence tracks, also shows that the submarine probably fired its two torpedoes, one at the battleship Oklahoma and the other at the battleship West Virginia, Mr. Rodgaard said."

HMC-FMF-PJ
01-05-2010, 01:29
One of the Pearl Harbor photo's
http://www.aerospaceweb.org/question/hydrodynamics/pearl-harbor/battleship-row2.jpg

And an article on the sub attack

Midget Submarines at Pearl Harbor
http://www.aerospaceweb.org/question/hydrodynamics/q0280.shtml

A controversial recent theory about the missing midget sub is based on one of the photos snapped by a Japanese plane during the attack. During the 1990s, a group of researchers performed a detailed study of this photo and found evidence that a midget submarine may have successfully penetrated the harbor and accomplished its primary mission of attacking ships on Battleship Row. The photo, shown below, was taken from a Nakajima B5N2 "Kate" torpedo bomber shortly after the first wave of air attacks had begun. Clearly visible are the tracks of several torpedoes headed towards the ships moored along Battleship Row. One region of the photo in particular also shows a curious black rectangular object that was the subject of the investigation. A description of the analysis performed on the image is described in a 1999 article from the U.S. Naval Institute

.......

Even more conclusive evidence to prove or disprove this theory may exist with the midget submarines themselves. Japan confirmed that five of the vessels participated in the attack and three have already been recovered. HA-19 was captured with its torpedoes still aboard since the sub was never able to enter the harbor. Raised after the attack was the submarine sunk by the Monaghan that had fired its torpedoes harmlessly into the shoreline and not into any of the ships along Battleship Row. The submarine discovered outside the entrance to the harbor in 1960 was also raised with its torpedoes still aboard.

.....

Only one of the midgets remains unaccounted for, so we do not yet know whether its torpedoes are still aboard. Nonetheless, we do know the St. Louis was attacked by an apparent midget submarine that fired its torpedoes as the American cruiser was traveling through the harbor entrance. Given this information, none of the midget subs could have launched an attack on Battleship Row. Until the final submarine is discovered, however, the mystery of whether it could have successfully accomplished its mission may be impossible to solve.

dvldocjoe
01-05-2010, 01:32
No matter how it was carried out, that attack was decisive for the war in a lot of ways. I am fascinated with the historical and strategic aspects of it.

Tim Bates
02-19-2010, 06:00
In regard to the large Japanese sub which was a plane carrier, interviews and records recovered after the war suggest one of the sub's original missions was to wreck part of the Pananma Canal by damaging the Pacific side lock. This would have put the waterway out of commision for months. Japanese subs were as advanced as US Gato class subs with superior Long Lance torpedoes. The mind set of their sub force was to attack US warships which proved highly dangerous since part of the IJN codes were compromised.