Giant Manta Ray underwater drone passes first military ocean test in California

The United States Navy has tested a new self-driving, manta ray-shaped underwater drone that can hibernate on the sea floor for long periods.

The prototype is part of a project to develop a new class of underwater drone capable of carrying out much longer missions - without supervision or the need to refuel.

Funded by the US Department of Defense’s Defense Advanced Research Projects Agency (DARPA) programme, and built by defence company Northrop Grumman, the autonomous craft has just undergone three months of testing off the coast of Southern California. 

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It uses "efficient, buoyancy-driven gliding to move through the water" said Dr. Kyle Woerner, the DARPA program manager for Manta Ray.

Adding, "Our successful, full-scale Manta Ray testing validates the vehicle’s readiness to advance toward real-world operations".

"The craft is designed with several payload bays of multiple sizes and types to enable a wide variety of naval mission sets."

The Manta Ray prototype was built in Maryland and shipped in sections to the test location in California.

"Shipping the vehicle directly to its intended area of operation conserves energy that the vehicle would otherwise expend during transit" said Woerner.

DARPA is engaging with the US Navy on the next steps for testing and transition of this technology.