RQ-4 Global Hawk (ACTD Program)
Defense Advanced Research Projects Agency

RQ-4A Global Hawk
Operator: Advanced Concept Technology Demonstration (ACTD) program
Timeframe: 1999-2001

Personal interest:
The first prototype of this high-altitude, long-endurance UAV, known as Tier II+, flew in February 1998. Redesignated RQ-4A Global Hawk, seven prototypes underwent testing until the 9/11 attack in 2001. At that point, the RQ-4A entered initial low-rate production while still in engineering and manufacturing development.