Type J1 submarine
1926 Japanese cruiser submarine class
The Type J1 submarine (巡潜1型潜水艦, Junsen ichi-gata sensuikan, "Cruiser submarine Type 1"), also called I-1-class submarine (伊一型潜水艦, I-ichi-gata sensuikan) were large cruiser submarines (Junsen type submarines) of the Imperial Japanese Navy.
Four boats were built between 1926 and 1929.
These boats, based on the KD2 and U-139 designs, were of a junsen, or cruiser, type with an impressive range of 24,000 nm. Elderly by 1941 they were among the first Japanese submarines converted to supply duty.
I-1 was present during the attack on Pearl Harbor and witnessed the Doolittle Raid on Tokyo, before patrolling the Aleutians. Her aft 14 cm gun was then removed to make room for a 46-foot (14 m) daihatsu cargo barge and she started shifting supplies in the Solomon Islands. On 29 January 1943, the New Zealand naval trawlers, Kiwi and Moa rammed and wrecked her in shallow water at Kamimbo Bay, Guadalcanal. A common rumor is that critical codes remained on board and the US Navy salvaged 200,000 pages of intelligence: code books, charts, manuals, and the ship's log. But this is due to a typo made in an intelligence report.
I-2 was sunk by the destroyer USS Saufley off New Ireland on 7 April 1944.
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This entry incorporates text from “Type J1 submarine” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.