Unmanned underwater vehicles (UUVs) have been around for come time and are becoming increasingly common in naval and civilian marine operations, but so far they have been small, short range, and restricted to their host vessels. Blue water underwater operations have been the reserve of large, manned submarines, but the purchase of the Orca indicates that the US Navy recognizes the growing importance of robotic submarines to the fleet.

Derived from Boeing's Echo Voyager, the Orca is diesel-electric powered and can be used for mine countermeasures, anti-submarine warfare, anti-surface warfare, electronic warfare and strike missions, among other applications. It has an open architecture, modular construction that includes a payload bay 34 ft (10.4 m) long with a volume of 2,000 cubic ft (56.6 cubic m).