The U.S. Navy is sending at least one unmanned Super Scorpio to help rescue seven crewmembers of a Russian mini-submarine, which is stuck on the Pacific sea floor. The Super Scorpios, which are controlled from the surface via a long tether, are used in search and recovery operations. They are based in San Diego.

Facts and figures about the Super Scorpio:

Maximum depth: 5,000 feet

Weight: 4,500 pounds

Dimensions: 4 feet by 4 feet by 8 feet

Speed: Four knots forward and aft, two knots laterally

Sensors: Sonar with 2,000-feet range