The U.S. Navy nearing decisions on small, medium UUV replacement options

The Mk 18 Mod 1 Swordfish and Mk 18 Mod 2 Kingfish date back to the late 1990s and 2000s. The former is a 150-pound small UUV that could be carried in and out of the water by a couple sailors; the latter is a 600-pound medium UUV primarily launched and recovered from a rigid-hull inflatable boat. The pair can be used for mine countermeasures and ocean survey, and the popular expeditionary mine countermeasures company (ExMCM) was built around an unmanned systems platoon that uses both vehicles.

The medium-size Razorback UUV has a program history more than a decade long, with the Navy initially seeking a UUV that could sense the littoral battlespace. The UUV the Navy first bought under the Razorback name will be launched and recovered via the dry deck shelter on some submarines, though the Navy has since changed course and is seeking a follow-on version that would be launched and recovered from a submarine torpedo tube.

These older technologies are reaching their limits even while the Navy continues to develop new sensors, target-recognition software and more that they’d like to put to sea, said Capt. Dan Malatesta, the program manager for expeditionary missions within the Program Executive Office for Unmanned and Small Combatants. The Lionfish small UUV and the Viperfish medium UUV programs that will replace these three legacy programs are both making good progress and should be ready to replace their predecessors in the next two to three years.

Lionfish completed a second user operational evaluation with an ExMCM company in May, he said Aug. 3 at the Navy League’s annual Sea Air Space conference. Two existing vehicles — L3Harris Technologies′ Iver 4 and Hydroid’s Remus 300 — are being considered for the program.

Lionfish would replace the Mk 18 Mod 1, which is based off the Remus 100 design from Hydroid. Malatesta said during his program update at the Naval Sea Systems Command booth the Mk 18 Mod 1 vehicle, which first saw use in Iraq in 2003, has “kind of maxed out its capability for computing power and those sort of things.” As a result, the Navy can’t integrate the newest sensors, autonomy packages and other updates onto the aging platform.

On the medium UUV side, the Razorback and the Mk 18 Mod 2 will merge into a single program called Viperfish. Malatesta said the Mk 18 Mod 2 and the Razorback are both based off the Remus 600 UUV design, so merging them into a single program won’t change the basics of how ExMCM companies or submarines handle and operate them. Viperfish is in source selection.