The Navy conducted the first taxi testing of the unmanned X-47B while at sea this week aboard the USS Harry S. Truman (CVN-75) aircraft carrier.

The X-47B was remotely maneuvered around the flight deck, allowing the Navy to get a sense of how the demonstrator aircraft operates in a carrier environment as the service prepares to conduct the first launch sometime next year.

The aircraft is steered by an arm-mounted control display unit by an operator standing on the flight deck. Additional flight testing will take place before the Truman returns to its homeport in Norfolk, Va.

The Navy has two of the X-47Bs built under the Unmanned Combat Air System Demonstrator (UCAS-D) program. Built by Northrop Grumman [NOC], they resemble smaller versions of the B-2 stealth bomber.

The second X-47B has remained at Naval Air Station Patuxent River, Md., where it is undergoing shore-based catapult test launches. The first one took place Nov. 29, bringing the planes closer to a carrier-based launch.

Capt. Jaime Engdahl, the program manager for Unmanned Combat Air System Demonstrator (UCAS-D), said after the ground-based test launch that a carrier launch could take place in 2013 (Defense Daily, Dec. 3, 2012).

The UCAS-D program is designed to produce an unmanned, carrier-based intelligence, surveillance and reconnaissance (ISR) aircraft with the ability to carry out precision strike operations, and to mature the technology ahead of the separate follow-on Unmanned Carrier Launched Surveillance and Strike (UCLASS) program.

The Navy originally planned to deploy a UCLASS system on an aircraft carrier by 2018, but announced in February that those plans were being pushed back by two years. The Navy in 2011 issued four separate UCLASS research and development contracts to Boeing [BA], General Atomics Aeronautical Systems, Lockheed Martin [LMT] and Northrop Grumman.