Posted by John McHaleWASHINGTON, 4 Sept. 2010. A Northrop Grumman-built NASA Global Hawk unmanned aerial vehicle (UAV) observed Hurricane Earl, days after it studied Tropical Storm Frank, as part of NASA's Genesis and Rapid Intensification Process (GRIP) experiment. GRIP is a NASA program designed to better understand how tropical storms form and develop into major hurricanes. The GRIP experiment is a NASA Earth science field experiment in 2010 that will capitalize on a number of ground networks, airborne science platforms, and space-based assets. The field campaign will be executed according to a prioritized set of scientific objectives.