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four of its 18 Ohio-class SSBNs and They can also operate without the wires, These weapons are launched over the side converted them to conventional cruise using their own active or passive sensors. of surface ships with the ubiquitous MK missile carriers. The ? rst four Ohio- They are programmed to detonate right 32 surface vessel torpedo tube launcher, class boats, 727 to 729, received the below the target, breaking its keel. or dropped into the water by aircraft. conversion between 2002 and 2008. In- Made by Raytheon, the MK 54 is the Both the lightweight and heavyweight stead of 16 Trident missiles, they carry current lightweight torpedo, although torpedoes use OTTO II fuel and PBXN 154 conventional Tomahawk land attack Mk 46 and MK 50s can be found in use. explosives in the warhead.

missiles, and have the ability to covertly deploy special operations personnel and equipment. The remaining 14 Ohios had four of their 24 missile tubes deactivated to meet the treaty obligations.

The lead ship of the class, USS Ohio (SSBN 726), was commissioned in 1981. She underwent a conversion and reclassi? ed as SSGN 726, rejoining the ? eet in 2006. The newest, USS Loui- siana (SSBN 743), was commissioned in 1997.

The Ohio Replacement Submarine (SSBN-X), now known as the Colum- bia-class, will begin to enter service in 2031. The lead ship, USS District of

Columbia (SSBN 826), honors the na- tion’s capital city. The Columbias are designed for a 41-year service life, with

U.S. Navy photo by Mass Communication Specialist 1st Class Devin M. Langer/Released an expected completion of 124 strategic deterrent patrols. The new SSBNs share roughly similar dimensions (length and displacement) with the Ohios; much of its strategic weapon capabilities with the Royal Navy’s Dreadnought class of

SSBNs; and have similar sensors as the

Virginia-class attack boats.

Below The Surface

TORPEDOES

IS WHAT MATTERS

Torpedoes come in two basic sizes— heavyweight and lightweight.

The Navy arms its submarines with

The results from our calculations heavy-weight 21-inch (diameter) MK48 and knowledge are hard at work.

torpedoes. Surface ships, maritime pa- trol aircraft and ASW helicopters use ? Thruster Design the lightweight 12.75-inch MK46, MK ? Vehicle Hydrodynamics 50 or MK 54 torpedoes.

? Propulsion Energy Budget

Many UUVs are designed to be de- ? Performance Improvements ployed from submarines. To be carried ? Silencing Propeller Noise about subs and launched while sub- ? Electric Motor Drives merged, many UUVs resemble torpedoes.

Let us expand your sea of

Mk-48 and Mk-48 ADCAP (advanced opportunities by providing capability) torpedoes are made by Lock- hydrocompinc.com/uv • 603.868.3344 design software and services heed Martin, and are wire-guided, which ® ® ® ®

NavCad • PropElements • PropCad • PropExpert for your team! means they can get constant updates re- garding the target and course to intercept. ©2024 HydroComp, Inc.

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