NAVYPEDIA

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I15 1940  

Ships

Name	No	Yard No	Builder	Laid down	Launched	Comp	Fate
伊15 [I15]			Kure K K	1/1938	7.3.1939	9.1940	sunk 10.11.1942
伊17 [I17]			Yokosuka K K	4/1938	19.7.1939	1.1941	sunk 19.8.1943
伊19 [I19]			Mitsubishi, Kobe	3/1938	16.9.1939	4.1941	sunk 25.11.1943
伊21 [I21]			Kawasaki, Kobe	1/1939	24.2.1940	7.1941	sunk 29.11.1943
伊23 [I23]			Yokosuka K K	1/1939	24.11.1939	9.1941	sunk 18.2.1942
伊25 [I25]			Mitsubishi, Kobe	2/1939	8.6.1940	10.1941	sunk 3.9.1943
伊26 [I26]			Kure K K	7/1939	10.4.1940	11.1941	sunk 24.10.1944
伊27 [I27]			Sasebo K K	7/1939	6.6.1940	2.1942	sunk 12.2.1944
伊28 [I28]			Mitsubishi, Kobe	9/1939	18.12.1940	2.1942	sunk 17.5.1942
伊29 [I29]			Yokosuka K K	9/1939	29.9.1940	2.1942	sunk 26.7.1944
伊30 [I30]			Kure K K	6/1939	17.9.1940	2.1942	sunk 13.10.1942
伊31 [I31]			Yokosuka K K	12/1939	13.3.1941	5.1942	sunk 13.6.1943
伊32 [I32]			Sasebo K K	1/1940	17.12.1940	4.1942	sunk 24.3.1944
伊33 [I33]			Mitsubishi, Kobe	2/1940	1.5.1941	6.1942	wrecked 13.6.1944
伊34 [I34]			Sasebo K K	1/1941	24.9.1941	8.1942	sunk 13.11.1943
伊35 [I35]			Mitsubishi, Kobe	9/1940	24.9.1941	8.1942	sunk 22.11.1943
伊36 [I36]			Yokosuka K K	12/1940	1.11.1941	9.1942	surrendered 8.1945, scuttled 1.4.1946
伊37 [I37]			Kure K K	12/1940	22.10.1941	3.1943	sunk 19.11.1944
伊38 [I38]			Sasebo K K	6/1941	15.4.1942	1.1943	sunk 12.11.1944
伊39 [I39]			Sasebo K K	6/1941	15.4.1942	4.1943	sunk 26.11.1943

Technical data

Displacement standard, t	2198
Displacement normal, t	2589 / 3654
Length, m	102.4 pp 106.9 wl 108.7 oa
Breadth, m	9.30
Draught, m	5.14
No of shafts	2
Machinery	2 Kampon diesels / 2 electric motors
Power, h. p.	12400 / 2000
Max speed, kts	23.6 / 8
Fuel, t	diesel oil 220
Endurance, nm(kts)	14000(16) / 96(3)
Armament	most: 1 x 1 - 140/40 11-shiki, 1 x 2 - 25/60 96-shiki, 6 - 533 TT (bow,17), 1 catapult, 1 seaplane (E14Y1) some: 2 x 1 - 140/40 11-shiki, 1 x 2 - 25/60 96-shiki, 6 - 533 TT (bow, 17)
Electronic equipment	93-shiki sonar, 93-shiki hydrophone
Complement	101
Diving depth operational, m	100

Standard scale images

Graphics

Project history

Otsu-Gata B1 type. Built under 3rd and 4th Supplementary programmes of 1937 and 1939. As design basis Kaidal 6b submarine was used with aviation armament as on Ko-Gata A1 type. Submarines of new "Model B" type (Otsu-Gata) differed from predecessors by more streamlined forms of hull and "CT-hangar" complex. Since Otsu-Gata there was an actual confluence of cruiser and fleet submarines development lines, as these boats intended both for long-range reconnaissance and for actions together with the surface forces. Double-hulled, endurance was about 90 days.

I17 differed from sisterships, that the hangar and a catapult placed aft from CT (accordingly 140mm gun was fitted fwd).

Part of submarines was completed under changed design: second 140mm gun fwd from CT was installed instead of hangar and catapult.

Modernizations

1943-44, some survived: + 2-shiki 2-go radar

Autumn 1944, I36, 37: - 1 x 1 - 140/40, 1 seaplane, 1 catapult and hangar; + 1 x 2 - 25/60 96-shiki, 4 Kaiten human torpedoes

late 1944, I36: + 2 Kaiten human torpedoes

Naval service

I23 after 15.2.1942 was lost S off Oahu (Hawaii), possibly she was sunk by US aircraft 26.2.1942. I28 17.5.1942 was sunk at Truck by US submarine Tautog. I30 13.10.1942 on approaches to Singapore was stricken by British mine and sunk, subsequently she was salvaged and broken up. I15 was sunk 10.11.1942 N off San Christobal by US destroyer-minesweeper Southard (under other data, she was sunk 2.11.1942 in the same place by US destroyer McCalla). I31 after 13.5.1943 was lost, possibly she was sunk 13.6.1943 N off Kiska by US destroyer Frazier. I17 was sunk 19.8.1943 SE off New Caledonia by New Zealand corvette Tui and US aircraft. I25 after 24.8.1943 was lost, under miscellaneous versions, she was mined at Espirito Santo in early September, 1943, or sunk NE off Espirito Santo 3.9.1943 by US destroyer Ellett. I34 was sunk 13.11.1943 at Penang by British submarine Taurus. I35 was sunk 22.11.1943 at Tarawa by US destroyers Meade and Frazier. I19 was sunk 25.11.1943 off Gilbert Islands by US destroyer Radford. I21 after 27.11.1943 was lost, possibly sunk 29.11.1943 at Tarawa by US carrier aircraft. I39 after 3.12.1943 was lost, presumably sunk 23.12.1943 by US escort destroyer Griswold in Solomons area. I27 was sunk 12.2.1944 NW off Addu (Maldives) by British destroyers Petard and Paladin. I32 was sunk 24.3.1944 in Marshall Islands area by US destroyers Halsey Powell, Hull, escort destroyer Manlove and patrol craft РС1135. I33 was foundered 26.9.1942 at Truck on shallow water as result of accident during after repair trials, salvaged 29.12.1942 and was under repair till May, 1944, she was foundered again on shallow water, having received a breach as a result of navigating accident 13.6.1944 during gears tests off Kure, secondary raised in July, 1953 and handed over on demolition. I29 was sunk 26.6.1944 at Philippines by US submarine Sawfish. I26 was sunk 24.10.1944 at Samar by US escort destroyer Coolbaugh (by other version, sunk 28.10.1944 NE off Surigao Straits by US destroyers Gridley and Helm). I38 was sunk 12.11.1944 in Carolina Islands area by US destroyer Nicholas. I37 was damaged 27.4.1944 S off Penang by British mine, repair and conversion to Kaiten carrier lasted till beginning of autumn 1944, she was sunk 19.11.1944 at Palau by US escort destroyers Conklin and McCoy Reynolds. I36 was scuttled by Americans 1.4.1946.