DARPA UNVEILS GROUNDBREAKING UNDERWATER VEHICLE PROTOTYPE
The DARPA Manta Ray uncrewed underwater vehicle (UUV) is a large-format autonomous submarine developed by Northrop Grumman that completed its first full-scale in-water testing off the coast of Southern California in early 2024. Designed for long-duration, long-range maritime operations without a crew or surface support ship, the Manta Ray represents a new class of autonomous underwater vehicle that could fundamentally change how navies conduct deep-sea surveillance, logistics, and payload delivery.
What Is the DARPA Manta Ray UUV?
The Manta Ray is part of DARPA's programme to develop extra-large uncrewed underwater vehicles capable of operating autonomously over extended periods and long distances in dynamic maritime environments. Unlike conventional UUVs that require regular support from surface ships for battery charging, payload maintenance, and mission re-tasking, the Manta Ray is designed to be self-sufficient over long deployments. Northrop Grumman was awarded the development contract and completed the full-scale prototype that underwent sea trials in February and March 2024, with tests conducted by the Naval Information Warfare Center Pacific off the Southern California coast.
What Does the Manta Ray's Modular Design Enable?
One of the most important operational features of the Manta Ray is its modular construction. The vehicle can be disassembled into subsections compact enough for cross-country transport via standard shipping logistics, then rapidly assembled on-site close to the operational area. This eliminates the need to sail the vehicle long distances from a home port before a mission begins, conserving the very energy reserves it would need for the actual task. Once in the water, the Manta Ray uses buoyancy-driven gliding as its primary mode of energy-efficient transit, activating propellers and control surfaces for more demanding manoeuvres. During the 2024 tests, the vehicle demonstrated gliding, ascending, descending, turning, hovering, and anchoring, with several of these operations conducted autonomously.
Propulsion and Autonomy
The Manta Ray uses three distinct propulsion and steering mechanisms: buoyancy control, propellers, and control surfaces. Buoyancy-driven gliding is the most energy-efficient mode and is suited to long-transit legs where time is not critical. Propellers provide active thrust for manoeuvring and holding station against currents. Control surfaces provide attitude control in pitch, roll, and yaw. The combination allows the vehicle to adapt its energy expenditure to the operational requirement, extending mission endurance significantly compared to propeller-only designs. Autonomous operation reduces the need for on-site human logistics, allowing the vehicle to execute missions with minimal real-time supervision.
What Comes Next for the Manta Ray?
Following the successful 2024 sea trials, DARPA confirmed it is working with the U.S. Navy on the next phase of testing and the pathway to transitioning the Manta Ray into active naval service. The vehicle will need to demonstrate payload integration, long-duration endurance runs, and operational scenarios before it can be fielded. The significance of a verified extra-large UUV prototype cannot be overstated: it establishes a new standard for autonomous underwater capability that peer competitors will need to match. For those fascinated by underwater vehicles and personal submarine technology, explore the TheArsenale Submarines collection, which includes personal submarines such as the NEMO Submarine and the Aurora-3C Personal Submarine.
Photo: DARPA
