Philippine Marines Receive U.S. T38 Devil Ray Sea Drones as South China Sea Pressure Persists.

The Philippine Marine Corps has received two American-made T38 Devil Ray unmanned surface vessels as Manila strengthens its ability to monitor waters facing sustained Chinese naval and coast guard activity. Accompanied by a local training and maintenance center at Subic Bay, the delivery supports a broader Philippine effort to improve maritime awareness across the South China Sea and approaches to the Luzon Strait, where detecting and tracking vessels has become increasingly important to military planning.

A MANTAS T-38 unmanned surface vessel operates in the Arabian Gulf during U.S. 5th Fleet evaluations on December 4. The Philippine Marine Corps has received two T38 Devil Ray vessels to support maritime surveillance. Archive image; the vessel pictured is not one of the Philippine-delivered craft. (Picture source: U.S. Department of War/Defense)

Key Tactical Insights:

• Maritime awareness: The U.S. T38 unmanned surface vessels could provide additional surveillance positions without placing crews aboard each vessel, supporting the Philippine Marines’ expanding role in monitoring contested waters and strategic passages.

• Mission integration: Payload capacity creates options for sensors and communications equipment, but useful surveillance depends on the installed configuration and the ability to send observations to commanders.

• Sustained availability: Local training, repairs and spare parts support could help turn delivery into repeatable operations. Public reporting does not yet establish continuous patrol coverage or the receiving Marine formation’s readiness.

The U.S. Company MARTAC announced the delivery on November 9, 2026, following the November 4 handover at Subic Bay. BusinessMirror reported that U.S. Ambassador Lee Lipton transferred the vessels to Philippine Marine Corps Deputy Commandant Brig. Gen. Bayani Curaming. The ceremony also marked the opening of the manufacturer’s Unmanned Center of Excellence, intended to support Philippine operators.

Related Topic: MARTAC Adds Capacity for 100 Devil Ray USVs a Year as U.S. Navy Pushes for Unmanned Maritime Mass

Maritime pressure drives Philippine surveillance requirements

The transfer comes amid continuing encounters around disputed maritime features. On November 10, GMA News reported that the Armed Forces of the Philippines had monitored 29 Chinese navy and coast guard vessels around Second Thomas Shoal, Scarborough Shoal, Sabina Shoal and Thitu Island during November 3–8. That Philippine military assessment illustrates the continuing demand for surveillance across several geographically separated locations. It does not establish that the newly delivered drones have been assigned to any of them.

The security challenge also extends northward. USNI News reported in October that encounters between Philippine and Chinese forces had increased across the South China Sea, with additional tensions near the Batanes Islands in the Luzon Strait. These northern islands overlook a passage used by commercial shipping and military vessels transiting the First Island Chain. The resulting surveillance requirement encompasses both contested shoals to the west and strategically important approaches to the north.

For the Philippine Marines, unmanned vessels fit an evolving mission that increasingly includes coastal sensing and maritime observation. Naval News reported that the service has been developing small boat units and sensing teams while adjusting force positioning around strategic chokepoints. In that setting, the Devil Ray’s potential contribution is an additional mobile sensor carrier. Its usefulness will depend on how its observations are incorporated into the wider Philippine maritime picture.

What is the U.S. T38 Devil Ray unmanned surface vessel?

The T38 Devil Ray is a powered catamaran developed by Florida-based Maritime Tactical Systems, or MARTAC, to carry mission equipment without an onboard crew. Its manufacturer describes control modes ranging from direct operator control to autonomous navigation. Its modular architecture is intended to accommodate reconnaissance, electronic warfare, mine countermeasures, and logistics payloads; those advertised roles do not confirm the equipment installed aboard the Philippine craft.

MARTAC’s delivery announcement describes an 11-meter vessel with burst speeds above 60 knots and a maximum payload of 1,814 kilograms. Its current product page instead lists a length of 12.2 meters and burst speeds above 50 knots. The company does not explain that discrepancy in the material reviewed, so the figures require configuration-specific clarification before they can be treated as the delivered vessels’ verified performance.

Operationally, speed can help a craft reposition, while payload capacity provides room for mission equipment. Neither independently establishes persistent surveillance. Endurance, sea conditions, sensor performance and communications connectivity determine how long a vessel can collect and transmit useful information. Autonomous navigation also does not, by itself, mean autonomous weapons employment.

U.S.-Philippine defense relations connect equipment with deterrence

The delivery forms part of a defense relationship anchored in the 1951 Mutual Defense Treaty. The allies’ 2023 Bilateral Defense Guidelines reaffirm that an armed attack in the Pacific, including the South China Sea, against either country’s armed forces, public vessels or aircraft—including coast guards—would invoke mutual defense commitments under Articles IV and V. Those commitments concern armed attacks; they should not be presented as an automatic military response to every maritime confrontation.

The same guidelines prioritize Philippine defense modernization, interoperable equipment, training and expanded maritime cooperation. They also identify infrastructure improvements, joint use of facilities and rotational U.S. access under the Enhanced Defense Cooperation Agreement as areas for deeper cooperation. The Devil Ray transfer adds a tangible maritime surveillance component to that wider relationship, although the announcement does not establish that the craft are connected to U.S. operational networks.

The two Marine Corps vessels follow the Philippine military’s receipt of one T38 and four smaller MANTAS T12 craft in mid-2024. Their arrival therefore expands an existing Philippine unmanned maritime effort into a distinct Marine Corps capability. The Subic Bay support center addresses the accompanying need for operator instruction, maintenance, and spare parts, but sustained patrols and demonstrated integration will show how much operational value follows the handover.

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Written by Alain Servaes – Chief Editor, Army Recognition Group
Alain Servaes is a former infantry non-commissioned officer and the founder of Army Recognition. With over 20 years in defense journalism, he provides expert analysis on military equipment, NATO operations, and the global defense industry.