Legacy Navigational Light Panel Retrofits to LED Navigational Lights

This is a 13-dual circuit navigation light control panel configured for military sealift and coast guard operations, including MSC T-AKE dry cargo/ammunition ships and USCG National Security Cutters (WMSL). The panel is equally well-suited to other government hulls of similar size and mission complexity, including USCG WMSM (Heritage-class Offshore Patrol Cutters) and MSC fleet ocean tugs (T-ATF).

The panel provides centralized management of the vessel’s entire navigation and signaling light suite from a single control station, typically installed on the bridge or in the wheelhouse. Every light circuit is equipped with automatic primary-to-secondary redundancy, meaning that if a primary lamp fails, the secondary lamp on that circuit is energized automatically — a critical feature for maintaining COLREG compliance and vessel safety without requiring crew intervention during high-tempo operations, heavy weather, or darkened-ship conditions. This dual-circuit architecture is particularly important for government vessels that may operate for extended periods without access to depot-level maintenance or spare parts.

The electrical design emphasizes survivability. The panel accepts dual 10-amp main power inputs, allowing it to be fed from separate electrical buses or switchboards — a standard requirement on naval and coast guard vessels where power distribution redundancy is integral to damage control doctrine. In the event of a loss of normal power to the panel, an audible alarm sounds independently to alert the bridge watchstander, prompting an immediate switch to the emergency power source via the dedicated emergency run fuse. This ensures that navigation lighting can be restored rapidly even during casualty power conditions.

All individual light circuit fuses are rated at 3 amps maximum, providing overcurrent protection appropriate for LED navigational fixtures including the Phoenix LED SturdiSignal series. Audible and visual alarms (red indicator lamps) are provided on every circuit to immediately identify a light failure or blown fuse. The alarm test push button allows the watchstander to simultaneously energize all circuits and verify lamp function during pre-underway checks or watch turnover — a standard requirement under both U.S. Navy and Coast Guard navigation light testing procedures.
The pilot light with high/low dimmer allows the bridge team to adjust panel illumination to match ambient lighting conditions, preserving night vision during darkened-ship or reduced-lighting operations — a routine consideration for military vessels operating in formation, during underway replenishment (UNREP), or in threat environments.

The panel is designed as a direct retrofit solution for vessels currently equipped with legacy incandescent navigation light systems, enabling a straightforward transition to modern Phoenix LED SturdiSignal fixtures without requiring rewiring of the underlying ship’s electrical distribution. This makes it particularly attractive for vessels undergoing Regular Overhaul (ROH), Drydocking (DD), or mid-life modernization where lighting system upgrades are included in the availability work package.

For military-adjacent vessels like an MSC dry cargo/ammunition ship (T-AKE) or a USCG National Security Cutter (WMSL), the navigation lighting suite must go well beyond basic running lights. These vessels routinely operate in multi-mission profiles that demand rapid reconfiguration of their lighting displays to communicate operational status to surrounding traffic. The 13-dual circuit capacity of the NLSM13DUG120A is specifically sized to accommodate this complexity, managing “Not Under Command” (NUC) signals for engineering casualties or loss of propulsion, towing/pushing light configurations for disabled vessel recovery operations, and fueling/RAS (Replenishment at Sea) lighting that signals restricted maneuverability during alongside underway replenishment — all critical capabilities for vessels that must be ready to shift between transit, station-keeping, replenishment, and emergency response roles on short notice.

The inclusion of two spare circuits provides additional flexibility for mission-specific or vessel-specific lighting requirements that may arise during the service life of the ship, such as additional obstruction lights, helicopter operations lighting interfaces, or special signals required by fleet operating procedures.