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Berry, Donald T.

Publications and source records attributed to Berry, Donald T..

Pilot Delays For Three Cockpit Controllers

Pilot effective delay increases with system delay. Report compares pilot effective time delays measured in simulations of aircraft-control systems equipped with Space Shuttle rotational hand controller and with two versions of conventional stick-type hand controller. Report of interest to those concerned with design of multiple-axis controllers in aircraft, armored vehicles, industrial machinery, and remote manipulators: operator response or delay critical to stable and accurate operation of such systems.

Privoznik, Cynthia M.↗

Longitudinal long-period dynamics of aerospace craft

Linear analyses are performed to examine the generic aspects of aerospace vehicle longitudinal long-period or trajectory modes of motion. The influence of Mach number, dynamic pressure, thrust-to-drag ratio, and propulsion system thrust laws on the longitudinal trajectory modes is presented in terms of phugoid frequency and damping and height mode stability. The results of these analyses are compared to flying qualities requirements where possible, and potential deficiencies in both the vehicle and the criteria are noted. A preliminary look at possible augmentation schemes to improve potential deficiencies is also presented. Interpretation of the practical consequences of the results is aided by typical time histories. Results indicate that propulsion system characteristics are the dominant influence on the longitudinal long-period flight dynamics of hypersonic aerospace craft. However, straightforward augmentation systems demonstrated the potential to accommodate these influences if the effects are included in the design process. These efforts may be hampered by a lack of design criteria for hypersonic aircraft.

Berry, Donald T.↗