FIGURE 2.1.1 Lockheed Martin/Air Force Research Laboratory’s Body Freedom Flutter aircraft, built by Lockheed Martin. This vehicle was designed to test the limits of aircraft structures, including the point of destructive flutter. The crash is therefore not an accident, but the end result of this test. This kind of flight research cannot be conducted with piloted vehicles and is cost prohibitive with full-scale vehicles. SOURCE: Courtesy of Jeff Beranek, Lockheed Martin.