The Department of Defense terminated DarkStar in January 1999, after determining the UAV was not aerodynamically stable and was not meeting cost and performance objectives.

[1] The RQ-3 DarkStar was designed as a "high-altitude endurance UAV", and incorporated stealth aircraft technology[2][3] to make it difficult to detect, which allowed it to operate within heavily defended airspace, unlike the Northrop Grumman RQ-4 Global Hawk, which is unable to operate except under conditions of air supremacy.

The DarkStar was fully autonomous: it could take off, fly to its target, operate its sensors, transmit information, return and land without human intervention.

Human operators, however, could change the DarkStar's flight plan and sensor orientation through radio or satellite relay.

Although the RQ-3 was terminated on January 28, 1999, a July 2003 Aviation Week and Space Technology article reported in April 2003 that a derivative of the RQ-3 had been used in the 2003 invasion of Iraq.