DARPA Awards Long-Range Unmanned Submarine Contracts

The US Defense Advanced Research Projects Agency (DARPA) has awarded Northrop Grumman and Martin Defense Group Manta Ray program phase 2 contracts to build long-range unmanned underwater vehicle (UUV) demonstrators.

The program was established to build large-payload UUVs to “operate without the need for on-site human logistics support or maintenance.”

The program’s first phase saw contractors employ “energy management, UUV reliability, biofouling and corrosion control, navigation, and undersea obstacle avoidance” technologies for long missions. The selected companies will develop separate systems.

To ‘Operate Independently of Crewed Vessels’

Manta Ray program manager Cmdr. Kyle Woerner stated, “DARPA’s Manta Ray program has made significant breakthroughs toward enabling payload-capable autonomous underwater vehicles to operate independently of crewed vessels or support infrastructure.”

“By investing in diverse solutions, DARPA strengthens our ability to transition innovative undersea technologies to our national security partners. Manta Ray is uniquely positioning itself to simultaneously introduce a new class of underwater vehicles while contributing key component technologies to other vital undersea programs.”

Extracts Energy From Ocean

Underwater vehicles are currently constrained by the amount of stored energy they can carry, limiting their range. They are unable to use wave and solar power like a surface vehicle. 

To overcome this challenge, Northrop, in partnership with Seatrec, is utilizing a device that extracts energy from the ocean’s thermal gradient and converts it into electricity. The ocean’s thermal gradient is the “difference in temperature between warmer mixed water near the surface and colder water below.”

Martin Defense Group is partnering with North Carolina State University, which has “expertise in underwater energy harvesting.” University researchers recently developed a “stretchable device that converts movement into electricity and can work in wet environments.”

Greater Endurance Than Orca

According to Forbes, the Manta Ray program should yield unmanned vehicles vastly outlasting the US Navy Orca’s stated endurance of 90 days underwater with conventional sources. The vessel is scheduled for induction in 2023.

Both developers will now undergo “subsystem testing and fabrication followed by in-water demonstrations of full-scale integrated vehicles.”