Ko-hyoteki class submarine
| (insert image and caption here) |
| General Characteristics |
|---|
| Displacement: | 46 tons submerged |
| Length: | 23.9 m (78.5 ft) |
| Beam: | 1.8 m (6 ft) |
| Height: | 3 m (10.2 ft) |
| Ballast: | 5899 lb (2,670 kg) in 534 times 11 lb (5 kg) lead bars |
| Designed Depth: | 30 m (100 ft) |
| Propulsion: | one electric motor, 600 horsepower (450 kW) at 1800 rpm, two screws conter-rotating on single shaft, leading prop 1.35 m diameter, right-handed; trailing prop 1.25 m diameter, left-handed |
| Batteries: | 192 trays of two two-volt cells each, 136 trays forward, 56 trays aft |
| Endurance: | 100 nautical miles at 2 knots, 80 nautical miles at 6 knots, 18 nautical miles at 19 knots |
| Speed: | 23 knots surfaced, 19 knots submerged |
| Complement: | one commander, one crewman |
| Armament: | two 18-inch torpedoes muzzle-loaded into tubes, one 300 lb (140 kg) scuttling charge (big enough to destroy the sub but not any other ships that may be near) |
The ko-hyoteki (甲標的, "Type 'A' Target") class of Japanese midget submarines had hull numbers but no names. For simplicity, they are most often referred to by the hull number of the mother submarine. Thus, the midget carried by I-16 was known as the I-16 midget. The midget submarine hull numbers beginning with the character "HA", which can only be seen on a builder's plate inside the hull.
Fifty were built. The "A Target" name was assigned as a ruse -- if their design was prematurely discovered by Japan's foes, the Japanese Navy could insist that the vessels were battle practice targets. They were also called "tubes" and other slang names.
The first two, Ha-1 and Ha-2, were used only in testing. They did not have conning towers, which were added to the later boats for stability underwater.
Ha-19 was launched by the I-24 at Pearl Harbor. Most of the other fifty hull numbers are unaccounted for, although several were captured in Sydney (Australia), Guam, Guadalcanal, and Kiska Island, accounting for some of the other hull numbers.
Five of these boats participated in the Pearl Harbor attack, with one actually making into the harbor. Of the five used at Pearl Harbor, one was captured and the other four sunk or lost.
A photograph taken from a Japanese plane during the Pearl Harbor attack appeared to show a midget submarine inside Pearl Harbor firing torpedoes at Battleship Row, but subsequent research has completely disproven this theory.
Type A midget submarines were also used to attack Sydney, Australia, and Diego Suarez, Madagascar.
References
- Ha-19 (Midget Submarine, 1938-1941): http://www.history.navy.mil/photos/sh-fornv/japan/japsh-h/ha19.htm
- Pearl Harbor Attacked website: http://www.pearlharborattacked.com
- Midget submarine attack on Sydney: http://www.awm.gov.au/atwar/remembering1942/midget_submarine/
