Target angle Angle on the bow provided the basis for submarine attack decisions through the world wars. When angle on the bow was less than 90° , the submarine would continue a submerged approach toward the target to launch torpedoes when angle on the bow increased to 90° indicating the minimum range torpedo launch opportunity for the submarine with the given target course and speed. Unless the target was already within torpedo range, angle on the bow greater than 90° required the submarine to attempt to surface and run around the target beyond visual range to submerge ahead of the target. As
Type 90 Ship-to-Ship Missile Type 90 Ship-to-Ship Missile The Type 90 Ship-to-Ship Missile (90式艦対艦誘導弾, SSM-1B) is a ship-launched anti-ship missile developed by Japan's Mitsubishi Heavy Industries that entered service in 1992. It is a naval version of the truck-launched Type 88 (SSM-1) missile, which in turn was developed from the air-launched Type 80 (ASM-1) missile. The Japan Maritime Self-Defense Force bought 384 of the missiles which it fitted to its "Akizuki", "Takanami", Hayabusa, and "Murasame"-class ships. With a range of , high subsonic speed and warhead, the Type 90 is similar to the US's RGM-84 Harpoon missile, and is replacing Harpoon on Japanese ships.