Aeroservoelastic Analysis of the B-2 Bomber

In the early stages of the development of the B-2 bomber, the technical challenges posed by the aeroelastic characteristics of the all-wing aircraft were recognized. The cone guration’ s near-neutral pitch stability and light wing loading made the aircraft highly responsive to atmospheric turbulence. This dictated the requirement for an active digital e ight control system to provide both stability augmentation and gust load alleviation. The gust load alleviation e ight control system was designed by a multidisciplinary team using a combination of optimal and classical control design techniques. The analytical models included linearized approximations of the digital control law mechanization. Flight-test data analysis included the extraction of the vehicle open-loop response, which compared well with the analytical predictions. The multidisciplinary design approach resulted in the successful development of a control augmentation system that provides the B-2 with superb handling characteristics, acceptable low-altitude ride quality, and substantial alleviation of gust loads on the airframe.