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Conventional Trident

The Pentagon proposed the Conventional Trident Modification program in 2006 to diversify its strategic options, as part of a broader long-term strategy to develop worldwide rapid strike capabilities, dubbed "Prompt Global Strike".

The US $503 million program would have converted existing Trident II missiles (presumably two missiles per submarine) into conventional weapons, by fitting them with modified Mk4 reentry vehicles equipped with GPS for navigation update and a reentry guidance and control (trajectory correction) segment to perform 10 m class impact accuracy. No explosive is said to be used since the reentry vehicle's mass and hypersonic impact velocity provide sufficient mechanical energy and "effect". The second version of conventional warhead is fragmentation version that would disperse thousands of tungsten rods which could obliterate an area of 3000 square feet. (appoximately 280 square meters).[6] It offered the promise of accurate conventional strikes with little warning and flight time.

The primary drawback would have been establishing sufficient warning systems so that other nuclear countries would not mistake it for a nuclear launch which could provoke a counterattack. For that reason among others, this project raised a substantial debate before US Congress for the FY07 Defense budget, but also internationally.[7] Russian President Vladimir Putin, among others, warned that the project would increase the danger of accidental nuclear war. "The launch of such a missile could ... provoke a full-scale counterattack using strategic nuclear forces," Putin said in May 2006.[8]
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http://en.wikipedia.org/wiki/Trident_(missile)


"(Conventional Trident Modification)'s advantages over other conventional strike capabilities is its ability to provide prompt response to threats around the globe," he said. "The (program) will allow national leadership to act in a crisis without a lengthy military buildup." Additional benefits of the Conventional Trident Modification are that it requires no forward-deployed or visible presence, has few if any requirements for allied overflight permission, and gives the enemy little or no warning before a strike, the spokesman said.

To ensure other countries don't mistake a conventional missile launch for a nuclear missile attack, DoD is developing confidence-building measures, such as advance notification and shared early warnings, he said. Also, DoD can borrow notification procedures from its long history of test launches of dual-role weapons systems. The Conventional Trident Modification program gives the United States a long-range strike option against targets beyond the range of current systems or that are heavily defended, the spokesman said. Also, the deployment of the program will send a message to adversaries that the United States is prepared to defend its national interests, he said. "If needed in the war on terrorism, the (Conventional Trident Modification program) can help deter state actors from sponsoring terrorism by imposing the threat of prompt conventional attack," he said.

This project supports efforts for both Advanced Strike Capability which will demonstrate the feasibility of producing intermediate size low cost rockets, and the development of a modification to the TRIDENT II (D5) strategic weapon system (SWS) to allow it to carry conventional payloads. The Conventional TRIDENT Modification (CTM) will adapt the TRIDENT II (D5) missile to carry conventional payloads.

Conventional TRIDENT Modification (CTM)

On 25 August 2003 the Department of the Navy, Strategic Systems Programs [SSP] issued a Request for Information (RFI) to determine the latest plans and programs including technology challenges and proposed solutions for affordable Submarine Launched Intermediate Range Ballistic Missiles (SLIRBMs), including launch considerations and potential payloads. Responses to this RFI were used by the Government to select presentations to be given at the upcoming SLIRBM Technical Exchange or to otherwise be reviewed by the government.

The SLIRBM requirements include: 1. System must be affordable 2. Range - IRBM 3. Missile diameter - 32.5 inches maximum [ie, half that of the current Trident-2] 4. Both conventional and nuclear payloads to be considered 5. Payload weights, diameters and length to be consistent with missile dimensions and range 6. Conventional payload system to have GPS accuracy 7. Missile subsystem hardened to Space Grade 8. Control of collateral damage to be considered (e.g., stage debris control) 9. Intermediate range ballistic missiles, including their payloads, and all of the launcher subsystem except for electronics, are to be contained within the 86 inch diameter TRIDENT missile launch tube 10. Usable missile tube length (for missile, payload and launcher) of 36 feet maximum.



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SLIRBM is a conventional missile concept that builds on the heritage the two companies share in US Navy strategic missile development. Lockheed Martin and ATK provide the US Navy with the submarine-launched Trident D5 nuclear ballistic missile.

SLIRBM is designed to precisely deliver a conventional payload on target at ranges in excess of 1100 miles within 10-15 minutes of launch. ...

Submarine Launched Intermediate Range Ballistic Missile (SLIRBM) / Submarine Launched Global Strike Missile (SLGSM)