Thread: Submarine Launched - Conventional Prompt Global Strike

The subject is getting renewed attention.

CTM (Conventional Trident Modification) is controvercial.

But also, the development of CTM is low hanging fruit (quick, easy, inexpensive, low risk effort, because reuses much existing tech).

I think that since there seems to be increasing desire for a longer range conventional strike weapon, at the same time that there is increasing scarcity of budget money for developing new weapons systems, the temptation to pick that low hanging fruit is probably increasing similarly.

USN leaving option open for prompt global strike from submarines

Daniel Wasserbly | 7/25/2012 | Jane's International Defence Review

Key Points:

--- The USN is still considering a conventional ballistic missile capability for its Ohio-class replacements

--- CPGS technology is still in its infancy, however, and the service is instead mainly focused on a Trident II D5 life-extension programme


The US Navy's (USN's) Strategic Systems Programs (SSP) office is leaving room to integrate a Conventional Prompt Global Strike (CPGS) capability on its Ohio Replacement submarines, but remains mostly focused on modernising Trident nuclear systems.

Pentagon officials have sought to better balance the portfolio of tools for US deterrence by adding CPGS to an arsenal of ballistic missile defence elements and nuclear-capable weapons, as response times for conventional weapons are often limited to days and weeks, whereas nuclear weapons can be deployed in a matter of hours.

CPGS is viewed as a potential circumvention of the nuclear taboo that adds strategic options, but there are challenges such as overflight of sovereign countries and, most importantly for the USN, a serious concern that a submarine-launched conventional weapon could be mistaken for a nuclear-armed submarine-launched ballistic missile (SLBM).

Rear Admiral Terry Benedict, the navy's director for SSP, said the service's submarine fleet offers some possible CPGS options, but much work remains to be done before moving forward again on any design or development efforts.

"I think there are still questions to be addressed with regard to ambiguity" when employing longer-range conventional strike systems from a submarine force, Adm Benedict said during a 20 July briefing in Washington, DC.

"I continue to believe that the submarine does offer a strong capability potential in conventional prompt global strike. We have a constant presence at sea, and certainly as it relates to the [SSGN cruise missile submarines] and to the capacity within the submarine, there are opportunities there," he said. "Having said that, we have taken clear direction from [Congress] with regard to our role in the development."

The navy has considered concepts such as the Conventional Trident Modification (CTM) as a potential solution for CPGS. The concept would replace two of the 24 Trident missiles on board an Ohio-class SSBN with conventionally tipped warheads. It has also examined similar efforts for SSGNs, but ultimately these projects were seen to be at best a niche capability and were limited in funding.

Adm Benedict noted, however, that a CPGS capability for new Virginia-class fast attack submarines (SSNs) could potentially be worked into a future updated version of the vessel, called the Virginia Payload Module (VPM).

The Pentagon announced in January 2012 that it was considering building Virginia-class boats procured in and beyond Fiscal Year 2019 (FY19) with added space in the mid-body section to integrate the VPM, which would house four large vertical launch tubes that could fire the legacy Tomahawk Land Attack Missile (TLAM), large-diameter unmanned underwater vehicles or, potentially, a new prompt strike missile to replace the long-serving TLAM.

Buying the smaller Virginia-class vessels with additional space for the VPM would notionally serve to fill a potentially sizeable weapons gap left when the larger Ohio-class SSGNs are retired in the mid- and late 2020s.

However, Adm Benedict said the VPM was still in an early concept phase and CPGS designs were not being ruled out. "The Virginia Payload Module right now is a conventional capability. The requirement today as it stands is a replacement for the SSGN Tomahawk shooters," he said.

The admiral added that discussions between the SSP office and the Program Executive Office for Submarines regarding the VPM's architecture included technical consultations to ensure the systems do not "preclude any future capability if leadership were to desire" that a CPGS be integrated.

"We are not in a design phase today ... [and so are not] designing a CPGS fire control subsystem for that module," Adm Benedict noted.

Meanwhile, despite the recent defence spending crunch and a slow shift away from strategic nuclear weapons, Adm Benedict said that for FY13 the Pentagon had requested ample funds to sustain the Trident II D5 Strategic Weapon System (SWS) on its Ohio-class SSBNs.

These sustainment efforts are focused on nuclear weapons security, the Trident II D5 SWS life-extension programme, the Ohio Replacement programme and opportunities for future collaboration with the US Air Force as both the air and sea services look to modernise their deterrent capabilities.

Trident II D5 weapon systems have been deployed on Ohio-class SSBNs for more than 20 years and are expected to see a service life of more than 50 years. Adm Benedict said that therefore "significant efforts will be required to sustain a credible and viable SLBM force from now until the end of the current Ohio-class SSBNs in the 2040s, as well as the entry into the service life for the Ohio Replacement SSBNs."

Among the navy's efforts to address the system's obsolescence are updates to the launcher, fire control, navigation, guidance, missile and re-entry subsystems. "Our flight hardware, missile and guidance life-extension efforts are designed to meet the same form, fit and function as the original system in order to keep the deployed systems as one homogeneous population and to control costs," he said.

The Ohio Replacement SSBN is planned to enter service with the Trident II D5 to save funding by maintaining one SWS during transition.