Japanese Situation
Japanese Operational Situation:
Prior kaiten (manned suicide torpedo) operations against the American navy while in harbor have had limited success. They have also been disastrous for the submarine force, with losses to our subs and sailors being very heavy as our forces withdrew from the closely defended harbors.
Operation Tembu (Heavenly Warrior) is designed to hurt the US forces in the forward battle area by sitting astride their supply line between Okinawa and Ulithi, attacking their supply convoys while avoiding their heavy harbor defenses.
In this hypothetical scenario, the Kaiten have found the Illustrious group.
Japanese Tactical Situation:
I-47 and her “Never Die” crew, along with I-36, have been assigned adjacent patrol areas athwart the Okinawa - Ulithi line. A message has been received from Admiral Miwa’s 6 th Fleet headquarters with news of a British carrier that has been badly damaged by our kamikaze warriors on April 1.
Japanese Forces:
I-47, Captain Orita Zenji (I-46 class SS) I-36, Commander Sugamasa Tetsuaki (I-15 class SS) Each submarine carries 6 Kaiten.
Japanese Orders:
Intercept the retiring British units and sink the damaged carrier.
Japanese Victory Conditions:
Decisive: Sink the crippled carrier, and escape with no losses.
Tactical: Inflict more damage points on the British forces than are received.
Japanese Setup:
Open ocean. The Japanese set up across the enemy’s known bearing of 170° at 10 nm. Spacing is up to the Japanese players.
Special Rules:
The Kaiten are launched from the decks of the mother submarines. It takes one Tactical Turn to prepare and launch each Kaiten. Only one can be launched per turn. Launch must occur while submerged, at periscope depth. Kaiten are launched at a target much the same as a regular torpedo, and move at 30 knots. They are controllable by the pilot.
On the turn of launch, each unit plots a course and the distance from the launch point where they will slow and come to periscope depth to take final bearings to the target, ideally about 400 – 600 yards. Final hit determination for the torpedo run is takem from the last point from which the pilot takes a bearing.
Special Notes:
Japanese vessels have radar and ESM. Include emissions status on turn orders. Kaiten Type 1 have a 1550 kg warhead. which inflict 258 damage points when they hit. Their range is 12.3 nm at 30 knots, 23.2 nm at 20 knots, and 41.9 nm at 12 knots. Their maximum speed is 30 knots. They have a maximum depth pf Shallow, and have two damage points. Because Kaiten do not have a fire control computer, their attack is less accurate than a torpedo attack from a conventional sub. During resolution, reduce the Kaiten’s chance to hit by dropping down four range tetps.
Historical Outcome
According to the captains involved, Operation Tembu was a great success. In a war patrol that started on April 20 th and ended on May 12 th , I-47 claimed six kills (five by kaiten and one by conventional torpedo attack), and I-36 claimed eight (four kaiten and four conventional).
The “Never Die Crew” of I-47 is a creative arrangement of the sub’s name in Japanese. When combined, shi (4), nana (7) and I make the word shinanai, an imperative meaning “never die.” Historically, they actually did refer to themselves as the “Never Die Crew.”
BT
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© Copyright 2003 by Larry Bond and Clash of Arms.
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