The US Navy is working to bring the Army’s PAC-3 MSE interceptor aboard its warships, giving the fleet another option against incoming missiles and other aerial threats. Lockheed Martin received a second-phase development contract in late September to integrate the interceptor with the Navy’s Aegis Combat System.The effort will adapt the Patriot Advanced Capability-3 Missile Segment Enhancement (PAC-3 MSE) for launch from the Mk 41 Vertical Launching System (VLS). Lockheed Martin is targeting land-based flight tests in 2027, followed by shipboard trials in 2028. The Navy aims to field the integrated system by 2029.The award follows an earlier $93 million contract that established PAC-3 MSE as an official Navy program. Lockheed Martin has also invested $120 million of its own funding to prepare the missile for maritime operations.Adapting the interceptor for shipsMoving PAC-3 MSE from land-based launchers to Navy warships requires significant engineering changes. The missile must work with the ship’s existing launch infrastructure and combat management architecture.Lockheed Martin is developing a new communications architecture with S-band and X-band capabilities. The design will support future upgrades as the Navy adapts its defenses to emerging threats.Engineers are also modifying the missile’s launch sequence timing software. Additional work includes new containerized fire-control software and a redesigned canister compatible with both Mk 41 VLS and PAC-3 MSE.The Mk 41 system presents a particular integration challenge. Its canisters must accommodate the interceptor without compromising the missile during launch. Lockheed Martin recently completed a push-through test to verify that PAC-3 MSE could pass through the Mk 41 canister without sustaining damage.Jason Reynolds, Lockheed Martin’s vice president and general manager for Integrated Air and Missile Defense, said the Navy partnership would bring a combat-proven interceptor into its maritime defense architecture.Testing the naval configurationThe program has already cleared an earlier launch milestone. In 2024, Lockheed Martin and US Department of War offices launched PAC-3 MSE vertically from an Mk 70 VLS launcher.The test also integrated the interceptor with a virtual Aegis Weapon System. It marked the first vertical launch of PAC-3 MSE under an Aegis integration configuration.The upcoming trials will take the effort further. A land-based flight test in 2027 will precede shipboard flight testing in 2028. These evaluations will help validate the integration before the Navy begins fielding the capability.PAC-3 MSE uses hit-to-kill technology, destroying incoming threats through direct impact. Its existing mission set includes tactical ballistic missiles, cruise missiles, and aircraft. Lockheed Martin also lists hypersonic missiles among the threats the interceptor can counter.Production faces growing demandThe Navy program arrives as the US military expands PAC-3 MSE production. On July 29, the Army awarded Lockheed Martin a $58 billion contract to accelerate manufacturing.The agreement supports a broader production expansion intended to triple manufacturing capacity. Demand comes from the Army, the Navy’s planned adoption, and international customers.Lockheed Martin is also working with the Army on production improvements across its supplier network. These efforts target manufacturing bottlenecks and component deliveries.The naval variant will share production lines with Army versions at Lockheed Martin’s All-Up Round III facility in Camden, Arkansas. That arrangement will support manufacturing as the Navy moves toward its 2029 fielding target.