April 24, 2010: Global Hawk Completed Scientific Research Flight to the Arctic and Back Published April 24, 2021 NASA EDWARDS AIR FORCE BASE, Calif -- National Aeronautic and Space Administration’s high-altitude, computer-controlled “Global Hawk” Unmanned aerial vehicle completed its longest scientific research flight to date – a 28-hour, 36-minute flight to the Arctic and back. Outfitted with 11 atmospheric monitoring instruments, the unmanned aircraft had taken off at 0013L on Friday, 23 April, from Edwards Air Force Base and landed at 0448L the next day after flying two passes at 85 degrees north latitude, about 340 miles from the North Pole. The flight was the third data-collection mission and the fourth overall in the 2010 Global Hawk Pacific, or GloPac, environmental science effort run by NASA and the National Oceanic and Atmospheric Administration. In the 1990s, the Air Force was developing uncrewed aerial intelligence platforms. One of them was the stealthy RQ-3 Dark Star, another one was the Global Hawk. Due to budget cuts, only one of the programs could survive. It was decided to proceed with the Global Hawk for its range and payload rather than go with the stealth Dark Star. The Global Hawk took its first flight on 28 February 1998. The first seven aircraft were built under the Advanced Concept Technology Demonstration (ACTD) program, sponsored by DARPA, in order to evaluate the design and demonstrate its capabilities. Demand for the RQ-4's abilities was high in the Middle East; thus, the prototype aircraft were actively operated by the USAF in the War in Afghanistan. In an unusual move, the aircraft entered initial low-rate production while still in engineering and manufacturing development. Nine production Block 10 aircraft, sometimes referred to as RQ-4A, were produced; of these, two were sold to the US Navy and an additional two were deployed to Iraq to support operations there. The final Block 10 aircraft was delivered on 26 June 2006. In order to increase the aircraft's capabilities, the airframe was redesigned, with the nose section and wings being stretched. The modified aircraft, designated RQ-4B Block 20, can carry up to 3,000 pounds of internal payload. These changes were introduced with the first Block 20 aircraft, the 17th Global Hawk produced, which was rolled out in a ceremony on 25 August 2006. First flight of the Block 20 from the USAF Plant 42 in Palmdale, California to Edwards Air Force Base took place on 1 March 2007. Developmental testing of Block 20 took place in 2008.