List of Japanese World War II navy bombs


This is a complete list of all aerial bombs used by the Imperial Japanese Navy during the Second World War.

Types

The Japanese navy produced a large number of different types of bombs, these were sub-divided into three main categories:

Bombs

DesignationTypeWeightContent weightContent typeConstructionLengthSuspension lugsNoseTailFuzeNotes
No.6Land Bomb 63.5 kgPicric acid or later Type 98 explosive Cast steelType 2 Model 2 mod 0 or mod 1Obsolete during the war. Case is similar to the Type 99 No. 6 Mk. 2
Type 97 No.6Land Bomb124 lb50 lbPicric acid or Type 98 explosiveWelded and riveted 1/4 inch steel40 inchesHorizontal navy typeCast steel7⅞ inches long sheet steelA-3Capable of penetrating 200 mm of reinforced concrete
Type 2 No.6 Model 5Land Bomb132 lb Five 7 kg high-explosive bombs with bursting chargeSheet 1/16 inch steel42 inchesHorizontal navy type-16¼ inchesA-3 or A-3
No.25Land Bomb550 lb330 lbType 98 explosiveWelded and riveted 1/4 inch steel72 inchesHorizontal navy typeCast steel36.5 inch long sheet steelA-3, A-3, C-2, C-1 Designed in 1938, production ceased early in the Second World War
Type 98 No.25Land Bomb532 lb211 lbPicric acid or Type 98 explosiveWelded and riveted 1/2 inch steel72 inchesHorizontal navy typeCast steel32.5 inch long sheet steelA-3, A-3, C-2, C-1 The bomb was used by Japanese forces at the Battle of Midway. Designed in 1937 adopted in 1938. Capable of penetrating 400 mm of reinforced concrete.
No.80Land Bomb1,760 lb842 lbPicric acid or Type 98 explosiveWelded and riveted 1/2 inch steel113 inchesHorizontal, two guide studs, and carrying bandCast steel41 inch long 1/8 inch steelA-1, B-3, A-3 The bomb was used by Japanese forces at the Battle of Midway. The bomb was designed in 1937 and adopted in 1938, and will penetrate 400 mm of reinforced concrete.
Type 99 No.25Ordinary Bomb550 lb132 lbType 91 explosive One piece of machine forged 3/4 inch steel68 inchesHorizontal navy type-28 inch long 1/16 inch steelA-3, A-3, B-2 Designed in 1938 and adopted in 1939, it is capable of penetrating 50 mm of armor.
Type 2 No. 50 Model 1Ordinary Bomb1,100 lb148 lbCast blocks of Type 98 explosiveOne piece of machine forged steel 1 to 7.5 inches thick78 inchesHorizontal, two guide studs and suspension band-39.5 inch long sheet steelA-3, B-2 Teardrop shaped
No.80 Model 1Ordinary Bomb1,820 lb770 lbType 91 explosiveOne piece of machine forged steel 0.75 inch thick111.5 inchesHorizontal, two guide studs, and suspension band-49 inch long 5/32 inch thick steelA-1, A-3, A-3, tail: B-3
No.3 Model 2Ordinary Bomb70 lb?Picric acidOne piece of machined steel33 inchesHorizontal stud on either side of the body-13.25 inchesA-1, A-3 Teardrop shaped. Obsolete since the early stages of the war.
No.6 Model 2Ordinary Bomb139 lb65 lbPicric acidOne piece of machined steel42.5 inchesHorizontal stud on either side of the body-17 inchesA-1, A-3 Teardrop shaped. Production ceased sometime between 1940 and 1941, although they continued to be used.
No.25 Model 2Ordinary Bomb557 lb228 lbPicric acidOne piece of machined steel 5/8 inch thick71.5 inchesHorizontal, navy type-27 inchesA-3, B-3 Teardrop shaped. The bomb was used by Japanese forces at the Battle of Midway
No.50 Model 2Ordinary Bomb1080 lb457.5 lbType 98 explosiveOne piece of machined steel 4 to 0.5 inches thick90 inchesHorizontal, two guide studs and suspension band-33 inchesA-3, B-3 Teardrop shaped
Type 99 No.6 Mk 2-140 lb85 lbType 98 explosiveCast nose plug welded to a 3/16 inch thick cylindrical body42 inchesHorizontal, two guide studs and suspension band-21 inchesA-3 A Mod 1 version of the bomb was also produced with a cylindrical steel anti-ricochet attachment spot welded to the nose giving it a blunt profile.
Type 1 No.25 Mk 2 Model 1-572 lb317 lbType 98 explosiveCast nose welded to a 1/4 inch thick cylindrical body72 inchesHorizontal, two guide studs and suspension band-21.5 inches followed
by a 15-inch plywood extension		A-3, B-3 A Mod 1 version of the bomb was also produced with a cylindrical steel anti-ricochet attachment spot welded to the nose giving it a blunt profile.
Type 99 No.80 Mk 5Armor-piercing1,641 lb66 lbType 91 explosiveSingle piece of machined forged steel 4 inches thick at the nose and two at the tail95.5 inchesTwo guide studs and suspension band-43⅜ inchesTwo B-2 tail fuzesTear drop shaped bomb, eight recesses around the nose could allow the fitting of a wind shield if used as a projectile. Adopted in 1941, basically a converted 40 cm AP shell, capable of penetrating 150 mm of armor.
Type 2 No.80 Mk 5Armor-piercing1,760 lb 100 lb Type 91 explosiveSingle piece of machined forged steel-Two B-2 tail fuzesIntended to supersede the Type 99 No.80. Not produced in large numbers. Designed in 1939, and adopted in 1942.
Type 3 No.150 Mk 5Armor-piercing3,300 lb 200 lb Type 91 explosiveSingle piece of machined forged steel-Two B-2 type tail fuzesIntended to supersede the Type 99 No.80. Not produced in large numbers. Designed in 1942 and tested in 1944, was in experimental production at the end of the war.
Type 3 No.25 Mk 8 model 1649 lb 263 lb Type 97 explosiveCast steel nose, welded to cylindrical body 0.5 inches thick67 inchesHorizontal type navyCast steel27⅜ inches longA-3
Type 3 No.6 Mk 23 model 1143 lb 50 lb Type 98 explosive
or Picric acid		Cast steel nose, welded and riveted to cylindrical body 0.25 inches thick40.75 inchesNormal type navyCast steel with anti-riccochet cone18½ inches longC-2
Type 4 No.25 Mk 29Air-to-air bomb--Explosive with white phosphorus filled steel pelletsSheet steel with wooden blocks in the nose----D-2 fuzeUnder development at the end of the war to replace No.25 Mk 3 for use against bomber formations, having a larger explosive charge and less incendiary shrapnel.
Type 3 No.25 Mk 31 Model 1Airburst378 lb175 lbType 98 explosiveSheet steel cylinder 0.5 inches thick with blunt nose62 inchesNormal navy typeBlunt steel with flange32 inchesType 3 electric firing device B-3Type 3 fuze triggers the bomb at a height of about 7 meters using an electro optical sensor.
Type 3 No.80 Mk 31 Model 1Airburst1,584 lb922 lbType 98 explosive cast into blocksSheet steel cylinder 9/16 inches thick with blunt nose113 inchesTwo guide studs and a suspension bandBlunt steel with flange41 inchesType 3 electric firing device B-3Type 3 fuze triggers the bomb at a height of about 7 meters using an electro optical sensor.
Type 5 No.25 Mk 33Airburst--Explosive with a layer of cylindrical steel fragments---Rounded with plummet fuze holder-Plummet electrical fuze with backup Type 15 model 2 fuzeThe bomb uses four retarding drogue plates that are opened by an atmospheric pressure fuze to slow descent and release the all-ways plummet fuze, which is suspended by a twenty-meter silk-clad copper to the main bomb. When the plummet fuze touches the ground the bomb is triggered.

Rocket bombs

The Japanese produced a number of bombs with rocket motors installed, intended for air-to-air use against bomber formations, or as armor-piercing weapons. Only two saw service, the Type 3 No.25 Mk 4 armor-piercing rocket bomb, and the Type 3 No.6 Mk.27 air-to-air rocket bomb.
ModelWeightDescription
Type 3 No.25 Mk 4 Mod 1315 kgWork on this design began in 1935 and production commenced in 1943. 1.9 meters long, the bomb is an armor-piercing design, with a thick forged steel nose. The bomb attained a speed of about 100 meters per second when launched. The principal drawback was the small 3.5-kilogram bursting charge.
Type 5 No.1 Mk 9 Mod 133 lbAn experimental design, intended for use against surfaced submarines. The bomb carried 2.2 pounds of explosives, and had a velocity of about 230 meters per second. Experiments were conducted in June 1944, and it was adopted in 1945. Production had started at the end of the war, but it had not been used. Capable of penetrating up to 25 mm of armor.
Type 3 No.6 Mk 9185 lbAn experimental design, intended for use against landing craft and small ships. The bomb carried 22 pounds of explosives, and had a velocity of about 230 meters per second.
Type 3 No.6 Mk 27145 lbAn anti-aircraft rocket that replaced the Type 99 No.3 Mk.3 in air-to-air bombing. It consisted of a large rocket motor with a 5.5 pound incendiary shrapnel warhead triggered by a clockwork time fuze with an adjustable delay of up to 10 seconds. The rocket had a maximum velocity of around 270 m/s, and the warhead contained 140 iron pellets with white phosphorus embedded in them, these were scattered in a 60 degree cone when the warhead was triggered. The bomb was designed in January 1944 and adopted in February 1945.
Type 3 No.1 Mk 2820 lbAn experimental anti-aircraft rocket with a 1.32-pound high-explosive warhead. Experiments were conducted in late 1944. This rocket used 2 kg of propellent and had a maximum velocity of 400 m/s.

Incendiary bombs

~ Type 45 No.44 Mk 6 bomb model 1

Gas bombs

Japanese Navy bomb fuzes designation system was unknown to the Allies until after the end of the Second World War. As a result, a designation system was created to describe the fuzes as follows. It consists of a capital letter, a numeral and a lower-case parenthetical letter.
The capital letter designates the fuzes type as follows:
The numeral approximates the order in which the fuzes were captured by the allies. Finally the lower-case letter in parentheses indicates the different but similar designs.
Where possible the original Japanese designation is given.