Japanese submarine I-168

The I-168 in March 1934.
History
Empire of Japan
Name:	I-168
Builder:	Kure Dockyard
Launched:	26 June 1933
Commissioned:	Kure Dock Yard on July 31, 1934
Fate:	sunk on 27 July 1943 by USS Scamp (SS-277)
General characteristics
Class and type:	KD6 Type, Kaidai class
Displacement:	1400 (1785 maximum) tons surface, 2440 tons submerged
Length:	322' 10"
Beam:	26' 11"
Draught:	15'
Propulsion:	Twin shaft Kampon 9000 horse-power/two stroke diesels bhp
Speed:	23 knots diesel/8.2 knots electric
Range:	14,000 nautical miles
Test depth:	230'
Complement:	60-84 officers and men
Armament:	6 Torpedo Tubes/14 21" torpedoes/1 X 4" AA Gun/1 X 13mm AA Gun

The Japanese submarine I-168 (I-68, until 20 May 1942) was a Kaidai type of cruiser submarine active in World War II. A KD6 sub-class boat, I-168 was built for the Imperial Japanese Navy (IJN) in the early 1930s. At the Battle of Midway she sank the only American warships lost in the battle: the aircraft carrier USS Yorktown (CV-5) and the destroyer USS Hammann (DD-412). At that time she was commanded by Lieutenant Commander Yahachi Tanabe.

The submarine was completed at the Kure Dock Yard on July 31, 1934. She was originally designated I-68. On November 23, 1941, I-68 and the rest of Submarine Squadron 3 were stationed near Hawaii to perform reconnaissance duties in preparation for the impending attack on Pearl Harbor. Still on station near Hawaii on December 13, I-68 was subjected to 21 separate depth charge attacks. The last attack damaged her batteries and flooded the aft torpedo tubes. After undergoing repairs at Kwajalein, I-68 conducted several uneventful patrols in the Pacific, before being redesignated I-168 on May 20, 1942 as part of a general submarine re-numbering program undertaken by the IJN.

I-168 was one of 13 submarines forming the Advance Expeditionary Force of the Japanese attack on Midway. Under the command of Tanabe Yahachi, she steamed south of Midway as far as Kure Island during her approach on 31 May 1942. The American aircraft carriers had passed through the area of the submarine patrol line before the submarines arrived on their patrol stations. I-168 spent the first three days of June observing Midway's southern horizon through the periscope by day and through binoculars at a range of five miles at night. I-168 observed and reported heavy aircraft activity indicating the island anticipated the Japanese attack. She made periscope observations during the first Japanese air attack on Midway. I-168 commenced shelling Midway with its 10-cm (4-inch) deck gun at 0130 5 June; but submerged when illuminated by shore searchlights after firing only 6 rounds.