Junsen type submarine

Class overview
Name: Junsen type submarines
Junsen I (I-1 class)
Junsen I Modified (I-5 class)
Junsen II (I-6 class)
Junsen III (I-7 class)
Builders: Kure Naval Arsenal
Kawasaki Shipbuilding
Operators: Imperial Japanese Navy
Built: 1923-1938
In commission: 1926-1945

Junsen (巡潜型, 水艦 Junsen-gata, "Cruiser Submarine"?) was a ship class of submarines of the Imperial Japanese Navy (IJN). There were four submarine designs of the Junsen type: J1, a modified J1, J2 and the J3.

Contents

Class variants

Junsens were divided into four types, Junsen I (巡潜一型 Junsen 1-gata, I-1 class?), Junsen I Mod. (巡潜一型改 Junsen 1-gata Kai, I-5 class?), Junsen II (巡潜二型 Junsen 2-gata, I-6 class?) and Junsen III (巡潜三型 Junsen 3-gata, I-7 class?).

Junsen I (I-1 class)

Four boats were built in 1923-1929. Genealogy of the large-size submarine in the IJN began with U-142. Japan received six U-boats from Germany as reparations of World War I. The IJN copied U-125, one of the six, producing the I-21 class minelayer submarine. The IJN could not find an optimal design of Fleet Submarine, so they and Kawasaki Heavy Industries sent many technical officers to the United Kingdom and Germany and got drawings of advanced submarines. The British L class became the Kaidai I, the K class became the Kaidai II and U-142 become Junsen I.

Boat Builder Laid down Launched Completed Results Fate
I-1 [1] Kawasaki Shipbuilding 12-03-1923 15-10-1924 10-03-1926 Damaged USS Hulbert 31-12-1941
Sank Dutch merchant ship Siantar 03-03-1942
Sunk by HMNZS Moa and HMNZS Kiwi at Guadalcanal 29-01-1943.
I-2 Kawasaki Shipbuilding 06-08-1923 23-02-1925 24-07-1926 Sank Dutch merchant ship Parigi 01-03-1942
Sank RMS Chilka 11-03-1942
Sunk by USS Saufley north of Rabaul 07-04-1944.
I-3 Kawasaki Shipbuilding 01-11-1924 08-06-1925 30-11-1926 Sank RMS Elmdale 07-04-1942
Sank RMS Fultala 08-04-1942
Sunk by USS PT-59 at Kamimbo 09-12-1942.
I-4 Kawasaki Shipbuilding 17-04-1926 22-05-1928 24-12-1929 Sank Norwegian merchant ship Hoegh Merchant 14-12-1941
Sank Dutch merchant ship Ban Ho Guan 28-02-1942
Sank USS Washingtonian 06-04-1942
Damaged unknown sailing boat 10-04-1942
Damaged USS Alhena 27-09-1942
Sunk by USS Seadragon southeast of Rabaul 20-12-1942.

Junsen I Mod. (I-5 class)

This is a type which added a float-plane to the Junsen I.

Boat Builder Laid down Launched Completed Results Fate
I-5 Kawasaki Shipbuilding 30-10-1929 19-06-1931 31-07-1932 Sunk by USS Wyman east of Saipan 19-07-1944.

Junsen II (I-6 class)

Project number S32. This is a type which added a catapult to the Junsen I Mod. She was built in 1931 under the Maru 1 Programme.

Boat Builder Laid down Launched Completed Results Fate
I-6 Kawasaki-Kōbe Shipyard 14-10-1932 31-03-1934 15-05-1935 Damaged USS Saratoga 12-01-1942
Sank RMS Clan Ross 02-04-1942
Sank RMS Bahadar 07-04-1942
Sank two unknown sailing boats 10-04-1942
Lost in an accident or sunk by enemy attacks, after 30-06-1944.

Junsen III (I-7 class)

Project number S33. These boats combined the good points of the Junsen II and the Kaidai V. They were built in 1934 under the Maru 2 Programme. Junsen III became a 'typeship' for the Type-A, B and C.

Boat Builder Laid down Launched Completed Results Fate
I-7 Kure Naval Arsenal 12-09-1934 03-07-1935 31-03-1937 Sank Dutch merchant ship Le Maire 04-03-1942
Sank RMS Glenshiel 03-04-1942
Sank USS Arcata 15-07-1942
Damaged by USS Monaghan at Kiska 21-06-1943. Scuttled 05-07-1943.
I-8 Kawasaki-Kōbe Shipyard 11-10-1934 20-07-1936 05-12-1938 Sank Dutch merchant ship Tjisalak 26-03-1944
Sank RMS City of Adelaide 30-03-1944
Sank Australian merchant ship Nellore 29-06-1944
Sank USS Jean Nicolet 02-07-1944
Sunk by USS Stockton southeast of Okinawa Island 31-03-1945.

Characteristics

Type Junsen I (I-1) Junsen I Mod. (I-5) Junsen II (I-6) Junsen III (I-7)
Displacement Surfaced 1,970 long tons (2,002 t) same as Junsen I 1,900 long tons (1,930 t) 2,231 long tons (2,267 t)
Submerged 2,791 long tons (2,836 t) 3,061 long tons (3,110 t) 3,583 long tons (3,640 t)
Length (overall) 97.50 m (319 ft 11 in) 98.50 m (323 ft 2 in) 109.30 m (358 ft 7 in)
Beam 9.22 m (30 ft 3 in) 9.06 m (29 ft 9 in) 9.10 m (29 ft 10 in)
Draft 4.94 m (16 ft 2 in) 5.31 m (17 ft 5 in) 5.26 m (17 ft 3 in)
Depth 7.58 m (24 ft 10 in) 7.58 m (24 ft 10 in) 7.70 m (25 ft 3 in)
Power plant and shaft 2 × Rauschenbach Mk.2 diesels
2 shafts
2 × Kampon Mk.1A Model 7 diesels
2 shafts
2 × Kampon Mk.1A Model 10 diesels
2 shafts
Power Surfaced 6,000 bhp 8,000 bhp 11,200 bhp
Submerged 2,600 shp 2,600 shp 2,800 shp
Speed Surfaced 18.8 knots (34.8 km/h) 20.0 knots (37.0 km/h) 23.0 knots (42.6 km/h)
Submerged 8.1 knots (15.0 km/h) 7.5 knots (13.9 km/h) 8.0 knots (14.8 km/h)
Range Surfaced 24,400 nmi (45,200 km) at 10 knots (19 km/h) 20,000 nmi (37,000 km) at 10 knots (19 km/h) 14,000 nmi (26,000 km) at 16 knots (30 km/h)
Submerged 60 nmi (110 km) at 3 knots (5.6 km/h) 65 nmi (120 km) at 3 knots (5.6 km/h) 80 nmi (150 km) at 3 knots (5.6 km/h)
Test depth 75 m (246 ft) 80 m (260 ft) 100 m (330 ft)
Fuel 545 tons 580 tons 580 tons 800 tons
Complement 75 75 80 100
Armament (initial) • 6 × 533 mm (21 in) torpedo tubess
(4 × bow, 2 × aft)
• 22 × Type 89 torpedoes
• 2 × 140 mm (5.5 in) L/40 11th Year Type Naval guns
• 1 × 7.7 mm machine gun
• 6 × 533 mm (21 in) torpedo tubes
(4 × bow, 2 × aft)
• 20 × Type 89 torpedoes
• 2 × 127 mm (5.0 in) L/40 Type 88 AA guns
• 1 × 7.7 mm machine gun
• 6 × 533 mm (21 in) torpedo tubes
(4 × bow, 2 × aft)
• 17 × Type 89 torpedoes
• 1 × 127 mm (5.0 in) L/40 Type 88 AA gun
• 1 × 13 mm AA gun
• 6 × 533 mm (21 in) torpedo tubes
(6 × bow)
• 20 × Type 89 torpedoes
• 2 × 140 mm L/40 11th Year Type Naval guns
• 2 × 13 mm AA guns
Aircraft and facilities • Hangar
• 1 × Yokosuka E6Y1
• Catapult and hangar
• 1 × Yokosuka E6Y1
• Catapult and hangar
• 1 × Watanabe E9W1 Slim

Footnotes

  1. ^ 伊号第1潜水艦 (I-Gō Dai-1 Sensuikan?). The same shall apply hereinafter.

Bibliography

See also