Japan
Torpedoes of World War II
Updated 08 September 2014

28 cm (11") Torpedo
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28 cm (11") Type 5 (1945)
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Ship Class Used On Small MTBs
Date Of Design 1945
Date In Service Not in service
Weight 507 lbs. (230 kg)
Overall Length 149.6 in (3.800 m)
Negative Buoyancy N/A
Explosive Charge 132 lbs. (60 kg) Type 97
Power / Range / Speed 10 HP / 1,640 yards (1,500 m) / 17-23 knots
Propulsion Kerosene-air wet-heater
Wander Left or Right (max) N/A
Notes:  Only two prototypes were completed before the end of the war.  Used a five-cylinder swashplate engine.
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45 cm (17.7") Torpedoes
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45 cm (17.7") Type 91 (1931) Mod 1
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Ship Class Used On Aircraft
Date Of Design 1931
Date In Service 1933
Weight 1,728 lbs. (784 kg)
Overall Length 208 in (5.275 m)
Negative Buoyancy 227 lbs. (103 kg)
Explosive Charge 331 lbs. (150 kg) Type 97
Power / Range / Speed 140 HP / 2,200 yards (2,000 m) / 41-43 knots
Propulsion Kerosene-air wet-heater
Wander Left or Right (max) N/A
Notes:  This was a pre-war torpedo although still in service ten years later.  "Nell" (G3M) torpedo bombers carried this weapon against the HMS Prince of Wales and HMS Repulse on 10 December 1941.
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45 cm (17.7") Type 91 (1931) Mod 2
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Ship Class Used On Aircraft
Date Of Design 1940
Date In Service 1941
Weight 1,841 lbs. (935 kg)
Overall Length 216 in (5.486 m)
Negative Buoyancy 271 lbs. (123 kg)
Explosive Charge 452 lbs. (205 kg) Type 97
Power / Range / Speed 140 HP / 2,200 yards (2,000 m) / 41-43 knots
Propulsion Kerosene-air wet-heater
Wander Left or Right (max) N/A
Notes:  Compared to Mod 1, Mod 2 had a heavier explosive charge, a thinner air vessel and anti-roll stabilizers.  It was first delivered in April 1941 and was carried into action by "Betty" (G4M) bombers against the Prince of Wales and Repulse.  A version of this torpedo heavily modified for use in shallow waters was carried by "Kate" (B5N) attack planes at Pearl Harbor.
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45 cm (17.7") Type 91 (1931) Mod 3
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Ship Class Used On Aircraft
Date Of Design 1941
Date In Service 1942
Weight 1,872 lbs. (849 kg)
Overall Length 216 in (5.486 m)
Negative Buoyancy 379 lbs. (172 kg)
Explosive Charge 529 lbs. (240 kg) Type 97
Power / Range / Speed 140 HP / 2,200 yards (2,000 m) / 41-43 knots
Propulsion Kerosene-air wet-heater
Wander Left or Right (max) N/A
Notes:  Compared to Mod 2, Mod 3 had a heavier explosive charge, the air vessel was thickened for a heavier charge.  Bronze parts were substituted for steel where possible and eight tail fins were experimented with in some units.
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45 cm (17.7") Type 91 (1931) Mod 3 Improved, Mod 3 Strong, Mod 4 Strong and Mod 7 Strong
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Ship Class Used On Aircraft
Date Of Design Improved:  1942
Strong:  1943
Mod 4:  1943
Mod 7:  1943
Date In Service Improved:  1943
Strong:  1944
Mod 4:  1944
Mod 7:  1944
Weight Mod 3 Improved and Strong:  1,872 lbs. (849 kg)
Mod 4: 2,030 lbs. (921 kg)
Mod 7:  2,319 lbs. (1,052 kg)
Overall Length All except Mod 7:  208 in (5.275 m)
Mod 7:  225 in (5.715 m)
Explosive Charge Mod 3 Improved and Strong:  529 lbs. (240 kg) Type 97
Mod 4:  679 lbs. (308 kg) Type 97
Mod 7:  926 lbs. (420 kg) Type 97
Negative Buoyancy All except Mod 7:  397 lbs. (180 kg)
Mod 7:  664 lbs. (301 kg)
Power / Range / Speed Improved:  140 HP / 2,200 yards (2,000 m) / 41-43 knots
Strong and Mod 4:  140 HP / 1,640 yards (1,500 m) / 41-43 knots
Propulsion Kerosene-air wet-heater
Wander Left or Right (max) N/A
Notes:  Compared to Mod 3, Mod 3 Improved had a heavier explosive charge, the top side of the afterbody and engine room strengthened with longitudinal T bars to permit 300 knot launching speed.  This was followed in 1944 by the Mod 3 Strong which had I instead of T bars for strengthening the top side of the afterbody and also the underside of the warhead nose, the air vessel was thinned with reduced pressure and range.  These modifications allowed a 350 knot launching speed.  Mod 4 was the same torpedo with a heavier explosive charge.  Mod 7 Strong had a longer, heavier warhead.
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45 cm (17.7") Type 94 (1934) Mod 2
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Ship Class Used On Aircraft
Date Of Design 1934
Date In Service Not in service
Weight 1,870 lbs. (848 kg)
Overall Length 208 in (5.283 m)
Negative Buoyancy N/A
Explosive Charge 331 lbs. (150 kg) Type 97
Power / Range / Speed N/A / 3,300 yards (3,000 m) (?) / 48 knots (?)
Propulsion Kerosene-air wet-heater
Wander Left or Right (max) N/A
Notes:  A limited number of these torpedoes were made but they do not appear to have entered service use.  Powered by a dual-row, eight cylinder radial engine with poppet valves.
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45 cm (17.7") Type 97 (1937)
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Ship Class Used On Midget Submarines
Date Of Design 1937
Date In Service 1939
Weight 2,161 lbs. (980 kg)
Overall Length 220 in (5.600 m)
Negative Buoyancy 553 lbs. (251 kg)
Explosive Charge 772 lbs. (350 kg) Type 97
Power / Range / Speed 205 HP / 6,000 yards (5,500 m) / 44-46 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) 90 yards @ 6,000 yards (80 m @ 5,500 m)
Notes:  Designed for Midget Submarines and was essentially a smaller version of the Type 93 and Type 95 torpedoes.  Only about 100 were made as similar problems with the first air vessel were found.  Used operationally only during the Pearl Harbor attack.
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45 cm (17.7") Type 98 (1938)
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WTJAP_WWII_Type_98_pic.jpg

Type 98 Torpedo on the beach at Sydney, Australia
Australian War Memorial photograph 305024

Ship Class Used On Midget Submarines
Date Of Design 1941
Date In Service 1942
Weight 2,094 lbs. (950 kg)
Overall Length 220 in (5.600 m)
Negative Buoyancy 487 lbs. (221 kg)
Explosive Charge 772 lbs. (350 kg) Type 97
Power / Range / Speed 152 HP / 3,500 yards (3,200 m) / 40-42 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) 45 yards @ 3,500 yards (40 m @ 3,200 m)
Notes:  Designed for Midget Submarines.  Also known as the Type 97 Special.  Worked on air enriched to 38% oxygen and bore the same relationship to the Type 97 as did the Type 96 did to the Type 95.  Called the Type 98 to fill a gap in the series, a total of about 130 were produced.  Used operationally during the attack at Sydney, Australia on 31 May 1942.
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45 cm (17.7") Type 2 (1942) and Type 2 Special
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Ship Class Used On Midget Submarines and MTBs
Date Of Design 1942
Date In Service 1943
Weight Type 2:  2,169 lbs. (984 kg)
Type 2 Special:  2,140 lbs. (975 kg)
Overall Length Type 2:  220.5 in (5.600 m)
Type 2 Special:  220.9 in (5.610 m)
Negative Buoyancy 584 lbs. (265 kg)
Explosive Charge 772 lbs. (350 kg) Type 97
Power / Range / Speed Type 2:  150 HP / 3,300 yards (3,000 m) / 39-41 knots
Type 2 Special:  150 HP / 2,200 yards (2,000 m) / 38-40 knots
Propulsion Kerosene-oxygen wet-heater
Wander Right or Left (max) 50 yards @ 3,300 yards (45 m @ 3,000 m)
Notes:  A modification of the aerial Type 91 Mod 3 with a larger air vessel and a different read buoyancy chamber.  Engine was an dual-row, eight-cylinder radial.  About 800 were made between 1943 and 1945.  In addition, there was a Type 2 Special of which about 100 were manufactured in 1944.  This had the same explosive charge but the smaller air vessel of the Type 91.
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45 cm (17.7") Type 4 (1944) Mark 2
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Ship Class Used On Aircraft
Date Of Design 1944
Date In Service 1945
Weight 2,169 lbs. (984 kg)
Overall Length 208 in (5.275 m)
Negative Buoyancy 690 lbs. (313 kg)
Explosive Charge 670 lbs. (313 kg) Type 97
Power / Range / Speed 140 HP / 1,640 yards (1,500 m) / 41-43 knots
Propulsion Kerosene-oxygen wet-heater
Wander Right or Left (max) N/A
Notes:  A further modification of the Type 91 Mod 3 Strong.  This version was strengthened to permit a launch speed of 400 knots.  The design was greatly simplified for easier production including the replacement of many steel parts by bronze. Also note that the designation system for modifications changed from "Mod" to "Mark" with this torpedo.
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45 cm (17.7") Type 4 (1944) Mark 4
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Ship Class Used On Aircraft
Date Of Design 1945
Date In Service 1945
Weight 2,434 lbs. (1,104 kg)
Overall Length 225 in (5.715 m)
Negative Buoyancy N/A
Explosive Charge 919 lbs. (417 kg) Type 97
Power / Range / Speed 140 HP / 1,640 yards (1,500 m) / 40-42 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) N/A
Notes:  Similar to the previous Type 4 Mod 2 with a larger warhead.  Later versions had a more pointed head, as noted for the earlier Models.  This gave an extra two knots in speed, as shown in the table above.
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53.3 cm (21") Torpedoes
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53.3 cm (21") Type 92 (1932) Mod 1 and Mod 2
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Ship Class Used On Submarines
Date Of Design 1932
Date In Service 1934 (1942 quantity production)
Weight 3,792 lbs. (1,720 kg)
Overall Length 281 in (7.150 m)
Negative Buoyancy 551 lbs. (300 kg)
Explosive Charge 661 lbs. (300 kg) Type 97
Power / Range / Speed 95 HP / 7,650 yards (7,000 m) / 28-30 knots
Propulsion Lead-acid electric batteries
Wander Left or Right (max) 130 yards @ 7,650 yards (120 m @ 7,000 m)
Notes:  The design of this torpedo was inspired by the German Navy's successful one of World War I.  Work started in 1921 and in 1925 workable models were produced.  Design work continued and the Type 92 Mod 1 was ready for production in 1934.  As there was no need for this torpedo at that time, the design was set aside.  In 1942 production started to supplement the Type 95 torpedoes.  The Type 92 was slower than the Type 95 but had even less track and was easier to produce.  The Type 92 Mod 2 was to have been based upon the German G7e and ten of these torpedoes were delivered to Japan in 1942.  However, a lack of manpower killed this project.  Homing gear based upon the comparison of sound intensity was studied for this torpedo, but it appears that the torpedo itself was too noisy for this to be successful.
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53.3 cm (21") Type 94 (1934) Model 1
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Notes:  Model 1 was an experimental aircraft torpedo using a kerosene, oxygen and sea water propulsion mixture that was apparently never made.  Reliable details are lacking.
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53.3 cm (21") Type 95 (1935) Model 1
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Ship Class Used On Submarines
Date Of Design 1935
Date In Service 1938
Weight 3,671 lbs. (1,665 kg)
Overall Length 354 in (9.000 m)
Negative Buoyancy 705 lbs. (320 kg)
Explosive Charge 893 lbs. (405 kg) Type 97
Power / Range / Speed 330 HP / 13,100 yards (12,000 m) / 45-47 knots
430 HP / 9,850 yards (9,000 m) / 49-51 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) 185 yards @ 9,850 yards (170 m @ 9,000 m)
270 yards @ 13,100 yards (250 m @ 12,000 m)
Notes:  A smaller version of the Type 93 developed for submarines.  As per the Type 93, later versions had a more pointed head, giving a similar two knot increase in speed, as shown in the table above.
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53.3 cm (21") Type 95 (1935) Model 2
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WTJAP_WWII_I-58_torp_pic.jpg

Forward torpedo room of I.58 on 28 January 1946 while awaiting scuttling at Sasebo, Japan
This submarine torpedoed and sank USS Indianapolis (CA-35) on 30 July 1945
USMC Photograph # 139986

Ship Class Used On Submarines
Date Of Design 1943
Date In Service 1944
Weight 3,814 lbs. (1,730 kg)
Overall Length 354 in (9.000 m)
Negative Buoyancy 849 lbs. (385 kg)
Explosive Charge 1,213 lbs. (550 kg) Type 97
Power / Range / Speed 330 HP / 8,200 yards (7,500 m) / 45-47 knots
430 HP / 6,000 yards (5,500 m) / 49-51 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) 100 yards @ 6,000 yards (90 m @ 5,500 m)
140 yards @ 8,200 yards (130 m @ 7,500 m)
Notes:  A slightly improved version, trading a shorter range for a much larger explosive charge.  As per the Type 93, later versions had a more pointed head, giving a similar two knot increase in speed, as shown in the table above.
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53.3 cm (21") Type 96 (1936 but actually 1941)
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Ship Class Used On Submarines
Date Of Design 1941
Date In Service 1942
Weight 3,814 lbs. (1,730 kg)
Overall Length 354 in (9.000 m)
Negative Buoyancy 705 lbs. (320 kg)
Explosive Charge 1,213 lbs. (550 kg) Type 97
Power / Range / Speed 400 HP / 4,900 yards (4,500 m) / 48-50 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) 76 yards @ 4,900 yards (70 m @ 4,500 m)
Notes:  This was a modified Type 95 Mod 1 torpedo developed because of troubles with the "first air vessel" in the former.  Type 96 used 36% oxygen rather than pure oxygen to reduce starting problems.  This also allowed a thin coating of lubricating oil to be used on valves where as with pure oxygen they had to be completely oil free which caused corrosion and irregular functioning.  The title of "Type 96" seems to have been given to fill a gap in the series.  As per the Type 93, later versions had a more pointed head, giving a similar two knot increase in speed, as shown in the table above.
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61 cm (24") Torpedoes
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61 cm (24") Type 93 (1933) Model 1, Mod 1, Mod 2 and Mod 3
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Ship Class Used On Surface Ships
Date Of Design 1933
Date In Service 1935
Weight 5,952 lbs. (2,700 kg)
Overall Length 354 in (9.000 m)
Negative Buoyancy 1,058 lbs. (480 kg)
Explosive Charge 1,080 lbs. (490 kg) Type 97
Power / Range / Speed 200 HP / 43,700 yards (40,000 m) / 36-38 knots
300 HP / 35,000 yards (32,000 m) / 40-42 knots
520 HP / 21,900 yards (20,000 m) / 48-50 knots
Propulsion Kerosene-oxygen wet-heater
200 hp @ 36-38 knots
300 hp @ 40-42 knots
520 hp @ 48-50 knots
Wander Left or Right (max) 550 yards @ 21,100 yards (500 m @ 20,000 m)
1,100 yards @ 35,000 yards (1,00 m @ 32,000 m)
1,640 yards @ 43,700 yards (1,500 m @ 40,000 m)
Notes:  Model 1 was the prototype version of the famous "Long Lance" torpedoes.  The first production version was Model 1 Mod 1.  This differed by having stronger ribs in the fore body, the strength of the rear buoyancy chamber was increased, more cooling water was supplied to the piston rods to prevent overheating and cracking, and the slide valve gearing was improved.

Mod 2 dated from 1936 and differed in many areas.  The oxygen vessel was made of a deep pressing with one integral end instead of a hollow forging.  This construction was followed in all subsequent versions.  The bracing ribs of the rear buoyancy chamber were further strengthened and cooling water to the slide valves was increased together with modifications to the buffer chamber, lubrication of the cross-head and group valve gearing.

Mod 3 was designed in 1944 and production started in 1945, but it did not enter service.  This mod combined the oxygen vessel and warhead of Mod 1 with the propulsion system of Model 3, described below.

Earlier versions of these torpedoes may be distinguished by their round-nosed heads.  Later versions had a more pointed head, developed as a result of tests upon Italian 50 knot torpedoes (probably the 53.3 cm W 270/533.4 x 7.2 Veloce).  This gave an extra two knots in speed, as shown in the table above.

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61 cm (24") Type 93 (1933) Model 2
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Notes:  Model 2 was an experimental type designed in 1935 to meet a staff requirement for a higher speed torpedo for destroyers.  Only two were built and experiments were discontinued until 1941.  In that year, two new engine designs were produced, both essentially modifications of the two-cylinder double-acting Whitehead type.  In the first engine, the cylinder bore was increased and the prototype with this engine achieved speeds of 51 knots.  The second engine had thicker cylinder walls and heads and stronger piston rods.  This engine developed pressures of 650 lbs./in2 (45 kg/cm2) and 850 HP.  The head of the torpedo was made to a finer, more streamlined design based upon Italian torpedoes, as noted above.  The propeller pitch was reduced and the RPMs increased.  This prototype made three runs at 56 knots over a 5,500 yard (5,000 m) course.  This design was not further pursued and did not enter service.
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61 cm (24") Type 93 (1933) Model 3
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Ship Class Used On Surface Ships
Date Of Design 1943
Date In Service 1944
Weight 6,173 lbs. (2,800 kg)
Overall Length 354 in (9.000 m)
Negative Buoyancy 1,279 lbs. (580 kg)
Explosive Charge 1,720 lbs. (780 kg) Type 97
Power / Range / Speed 200 HP / 32,800 yards (30,000 m) / 36-38 knots
300 HP / 27,300 yards (25,000 m) / 40-42 knots
520 HP / 16,400 yards (15,000 m) / 48-50 knots
Propulsion Kerosene-oxygen wet-heater
Wander Left or Right (max) 380 yards @ 16,400 yards (350 m @ 15,000 m)
760 yards @ 27,300 yards (700 m @ 25,000 m)
1,100 yards @ 32,800 yards (1,000 m @ 30,000 m)
Notes:  A slightly improved version, trading a shorter range for a much larger explosive charge.  The first air vessel was replaced by carbon tetrachloride to prevent an explosion on ignition.  Earlier versions of these torpedoes may be distinguished by their round-nosed heads.  Later versions had a more pointed head, as noted for the earlier Models.  This gave an extra two knots in speed, as shown in the table above.
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61 cm (24") F3 (Experimental)
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Ship Class Used On Ships
Date Of Design 1934
Date In Service Not in service
Weight 5,952 lbs. (2,700 kg)
Overall Length 336.6 in (8.550 m)
Negative Buoyancy N/A
Explosive Charge 1,102 lbs. (500 kg) Type 97
Power / Range / Speed 1,000 HP / 8,750 yards (8,000 m) / 60 knots
Propulsion Kerosene-Oxygen sea-water Turbine
Wander Left or Right (max) N/A
Notes:  Experimental Turbine powered torpedo.  Turbine speed was 17,500 rpm geared down to 1,650 rpm at the propellers.  It was found to be difficult to keep this torpedo from breaking surface during its runs and development was halted prior to the start of the Pacific War.
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Data from
"Naval Weapons of World War Two" by John Campbell
"Japanese Cruisers of the Pacific War" by Eric Lacroix and Linton Wells II
Page History

12 May 2008 - Benchmark
08 September 2014 - Added photograph of Type 98