Northrop Grumman’s [NOC] Manta Ray uncrewed underwater vehicle completed full-scale in-water testing earlier this year, the Defense Advanced Research Projects Agency (DARPA) said.

DARPA this week announced the Manta Ray conducted the testing in February and March off the coast of Southern California. Tests demonstrated the vessel’s at-sea hydrodynamic performance, covering submerged operations using all the vehicle’s modes of propulsion and steering including buoyancy, propellers, and control surfaces.

Manta Ray vehicle being towed in preparation for testing in early 2024. (Photo: Northrop Grumman via DARPA)
Manta Ray vehicle being towed in preparation for testing in early 2024. (Photo: Northrop Grumman via DARPA)

Last month, Northrop Grumman said it finished assembly of the Manta Ray prototype at its Annapolis, Md., facility (Defense Daily, April 8).

DARPA now said the company shipped the prototype in subsections from Maryland to California. 

It also argued this helped demonstrate how easy it is to ship and assemble this UUV using modular subsections, supporting the possibility of rapid deployment worldwide without taking up to much valuable naval pier space.

“Our successful, full-scale Manta Ray testing validates the vehicle’s readiness to advance toward real-world operations after being rapidly assembled in the field from modular subsections. The combination of cross-country modular transportation, in-field assembly, and subsequent deployment demonstrates a first-of-kind capability for an extra-large UUV,” Kyle Woerner, DARPA program manager for Manta Ray, said in a statement.

He also said shipping the UUV in parts conserves energy vs. having it transit the distance itself.

The Manta Ray is designed with several payloads and uses buoyancy-driven gliding to move in the water. DARPA intends the UUV  to demonstrate the option for a new class of long-duration and long-range UUVs with payloads of different sizes that does not require in-person human logistics.

DARPA said it is “engaging with the U.S. Navy on the next steps for testing and transition of this technology.”

The agency also said PacMar Technologies is continuing to test its full-scale energy harvesting system this year.

In 2021, DARPA first awarded contracts to Northrop Grumman and Martin Defense Group to move from Phase 1 to Phase 2.

In Phase 1 of Manta Ray the participants started designing and conducting preliminary testing on new approaches to energy management, UUV reliability, navigation and undersea obstacle avoidance.

Phase 2 included subsystem testing before moving to fabrication of this full-scale model.