The U.S. Navy’s ongoing modernization of its undersea fleet has received a substantial industrial boost. L3Harris Technologies has been awarded a $139 million follow-on contract from the U.S. Naval Sea Systems Command for the continued engineering, testing, and delivery of Low-Profile Masts (LPM).
Targeted directly at the Navy’s premier nuclear submarine lines—including the fast-attack Virginia-class and the next-generation Columbia-class ballistic missile submarines—this contract reinforces L3Harris’s status as the world’s leading provider of non-hull-penetrating submarine imaging systems and optronic sensors.
Specifications Breakdown
- Contract Value: $139 million follow-on award
- Awarding Agency: U.S. Naval Sea Systems Command (NAVSEA)
- Platform Integration: Virginia-class and Columbia-class nuclear submarines
- Core Hardware: Low-Profile Masts (LPM) Type 20 and Type 24 systems
- Primary Function: Non-hull-penetrating optronic digital imaging, replacing legacy optical periscopes with high-definition visible and infrared sensors providing full 360-degree coverage
Mechanical & Design Deep-Dive
The structural evolution from traditional optical periscopes to L3Harris Low-Profile Masts represents a fundamental shift in submarine architecture. Older periscopes required a massive optical tube running directly down through the pressure hull into the control room, creating a structural weak point and limiting spatial layout flexibility.
The LPM system replaces this with a slender, non-hull-penetrating telescoping arm equipped with high-definition digital and infrared cameras. Video feeds are routed electronically down to secure command stations, removing the need for a physical light path through the hull. Acting as prime contractor and design agent, L3Harris provides complete engineering support—from initial design and environmental testing through to final fleet delivery—ensuring these systems withstand high hydrodynamic pressures and corrosive saline environments.
Environment Suitability
Submarine mast systems must operate reliably in some of the harshest, most high-stakes operational environments on Earth. L3Harris’s imaging systems are engineered for minimal radar and visual cross-sections, allowing submarines to clear periscope depth discreetly in contested littoral waters.
The integration of advanced electro-optical and infrared (EO/IR) packages ensures high-clarity situational awareness during low-light operations, surface tracking, and intelligence-gathering missions, all while maintaining the acoustic and visual stealth required for modern undersea warfare.
Alternatives Analysis
While international defense contractors (such as Safran in Europe with the Series 30 family) produce competing non-hull-penetrating optronic masts, L3Harris remains the entrenched domestic supplier and foundational backbone for the U.S. Navy submarine fleet.
Unlike older hydraulic-actuated masts that carry potential oil leak risks inside the pressure hull, L3Harris’s modern mast configurations offer advanced electric actuation paths that reduce maintenance footprints, eliminate fluid contamination hazards, and streamline life-cycle sustainment costs across multi-decade naval service lives.
Summary Evaluation
The $139 million award to L3Harris underscores the critical importance of advanced sensor technology in maintaining American undersea dominance. By outfitting Virginia- and Columbia-class submarines with state-of-the-art Low-Profile Masts, the U.S. Navy secures a vital tactical advantage in digital reconnaissance, crew safety, and stealth capability for decades to come.