Trident II Mods

The TRIDENT II Mods program is a critical component of the U.S. Navy's strategic deterrence mission, supporting the continued viability and modernization of the TRIDENT II (D5) submarine-launched ballistic missile system. The goals of this budget line item are to ensure the reliability, safety, and effectiveness of the sea-based leg of the nuclear triad through targeted procurement, sustainment, and modernization activities. The program is structured into three major subcomponents: D5 Life Extension (D5LE), Operating and Support Costs, and D5 Life Extension II (D5LE2), each with distinct objectives and deliverables.

D5 Life Extension (D5LE) focuses on extending the operational life of the existing TRIDENT II missiles to meet the strategic requirements of the OHIO-class and future COLUMBIA-class submarines. Specific objectives include the procurement of Joint Fuze Sustainment kits, guidance system SPALT (Strategic Programs Alteration) kits, and missile electronics packages such as Flight Control Electronic Assemblies, Missile Inverters, and Command Sequencers. The program also funds production support activities, including system integration, restart efforts at key production sites, and quality assurance functions. In FY 2026, D5LE funding is primarily directed toward completing final procurements and supporting the transition to sustainment, with a reduction in hardware quantities as inventory objectives are met.

Operating and Support Costs are dedicated to the ongoing sustainment of both legacy D5 and upgraded D5LE missiles. This includes funding for warhead components, such as the W76-1/Mk4A Reentry Body assemblies and associated support equipment, as well as the Mk4B Shape Stable Nose Tip program, which enhances flight performance predictability. Additional objectives encompass the refresh and replacement of aging tooling and test equipment, system integration and planning, supportability modifications, and the replacement of aging rocket motors and electronic components.

The program also addresses critical industrial base recapitalization efforts for Solid Rocket Motors (SRMs) and Post Boost Control Systems (PBCS), ensuring production capacity and quality for future strategic needs. The Industrial Base Sub-Tier Recapitalization Strategic Solid Rocket Motor (SSRM) initiative within Operating and Support Costs is a multi-year investment designed to modernize the SRM industrial base. Its goals are to improve process technology, tooling, and techniques to current industry standards, thereby enhancing production predictability, quality, and throughput.

FY 2026 investments target chamber/case modernization, igniter/nozzle tooling upgrades, propellant/energetics requalification, and capital maintenance at Navy-owned ordnance plants. These efforts are essential for supporting the increased demand from both OHIO and COLUMBIA-class submarine patrols beginning in 2030.

D5 Life Extension II (D5LE2) represents the next phase of TRIDENT II modernization, focusing on detailed design and non-recurring engineering for Strategic Weapons Systems (SWS) subsystems, including missile, guidance, fire control, launcher, and navigation. FY 2026 marks a transition from system-level requirements setting to subsystem-level evaluations, redesign activities, and production/vendor engagement. Key objectives include airframe material and structural testing, propulsion engineering for inert test vehicles, electronics and avionics prototyping, controls hardware design and requalification, ordnance subsystem development, and activation planning for supporting facilities. These efforts are modeled after the successful D5LE strategy and utilize the SPALT approach to address obsolescence and inventory shortages.

D5LE2 also includes guidance system redesign, with FY 2026 activities centered on system design reviews, prototype sensor development, electronic parts procurement, and software integration. Ship interface objectives involve fire control subsystem modeling, launcher test tube production, and navigation subsystem preliminary design reviews. System evaluation funding supports requirements management, configuration control, architecture development, and integration planning for future system-level testing and assurance activities. These efforts are crucial for preparing the D5LE2 system for integration with COLUMBIA-class submarines and maintaining the performance envelope in a dynamic threat environment.