Unmanned Minespotter Passes a Key Test

Mechanical Engineering, Jan 2008 by Hutchinson, Harry

About a year after the program was restarted, the Boeing Co. says it has demonstrated that its experimental unmanned underwater reconnaissance vehicle can be sent out and retrieved by a submerged, moving submarine.

The unmanned craft was released at sea through one of the torpedo tubes from a U.S. Navy attack submarine. The vehicle returned to the sub, where it was drawn back through a torpedo tube by the systems robotic arm.

The submarine retrieved the craft on its first attempt and repeated the maneuver two days later.

Boeing said that the vehicle, designated AN/BLQ 11, also performed several complex maneuvers on its own during the tests, including station keeping and one called "shadow submarine," in which the unmanned craft operated underwater alongside the host submarine.

The craft contains side and front scanning sonar. It uses inertial guidance and GPS tracking to navigate and to reunite with the submarine. When the vehicle is back onboard, data can be downloaded and analyzed. The system can detect obstacles and minefields down to the positions of individual mines.

Boeing began work on the system in 1999. It was tested in January 2006, but the system's 60-foot robotic recovery arm suffered a mechanical failure during the test and the unmanned vehicle was not retrieved as planned. Boeing received an $11 million contract early in 2007 to repair the arm and continue development.

HARRY HUTCHINSON