Japanese
12 cm (4.7") AA Rocket
Updated 04 July 2006
The Imperial Japanese Navy developed a number of spin-stabilized rockets during World War II, but only this one ever saw service use.  These went to sea in 28-rocket launchers with six launchers on most carriers.  The rocket had an incendiary shrapnel warhead, somewhat similar in design to the "Sankaidan" Type 3 projectile used for guns, and had a time fuze set to explode the warhead at either 1,000 or 1,500 meters (1,100 or 1,640 yards).  They were electrically fired in pairs or automatically in 14-rocket sets, the latter taking 10 seconds.
WNJAP_12cm_AA_Rocket_sketch_pic.jpg

12 cm Incendiary Rocket
Sketch from US Naval Technical Mission to Japan report O-19:  Japanese Projectiles General Types
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Gun / Rocket Characteristics
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Designation 12 cm (4.7") AA Rocket
Ship Class Used On Carriers
Date Of Design 1944
Date In Service 1944
Firing Rails 42.65 in (1.083 m)
Warhead Weight N/A
Maximum Velocity 656 fps (200 mps)
Rate Of Fire 14 rockets in 10 seconds
Note:  Reloading was by hand.
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Range
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Range with time fuzes 1,100 or 1,640 yards (1,000 or 1,500 m)
Maximum Range
(ballistic)		 5,250 yards (4,800 m)
Maximium Height at 80 degrees about 7,545 feet (2,300 m)
Note:  Time fuzes were set to either 5.5 seconds or 8.5 seconds.  Propellant burnt for 1.6 seconds.
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Mount / Turret Data
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Designation 28-rocket launchers

Most Carriers (6) and Shinano (12):  Type 5 (1945)
Weight  3,521 lbs. (1,597 kg)
Elevation +5 / +80 degrees
Elevation Rate 18 degees per second
Train N/A
Train Rate 22 degrees per second
Notes:

1) These mountings were adapted from the 25 mm AA triple gun mounting and could be controlled by Ward-Leonard RPC or by two men in protected cabs.  The launcher resembled a large box which consisted of four rows of seven rockets each.

2) This rocket or a similar one with an HE warhead was also carried by some explosive motor boats fitted with a simple launching trough.

3) These launchers were not installed on Shinano before her loss.
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Data from
"Naval Weapons of World War Two" by John Campbell
"The 12 cm Multiple Rocket Launcher of the Imperial Japanese Navy" article by Hans Lengerer and Tomoko Rehm-Takahara in "Warship Volume IX"
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US Naval Technical Mission to Japan report O-19:  Japanese Projectiles General Types