Feedback control for penetrating a downburstFeedback logic is given that produces satisfactory penetration of an aircraft through a severe downburst. The logic has two parts: (1) A switch that calls for full throttle and tight climb-rate-hold feedback logic when the magnitude of headwind-rate exceeds a threshold level; this switch stays on until re-set by the pilot after penetration of the downburst. (2) A tight climb-rate-hold autopilot, using feedback of pitch-angle to angle-of-attack. After penetration, recovery to steady climbing flight is aided by using feedback of airspeed deviation to throttle. Insights on control strategy are gained from an analysis of energy changes during flight through a downburst. Closed-loop simulations are given for a 727 aircraft penetrating severe downbursts on take-off. Boeing's recommendation of constant pitch angle was confirmed as an excellent feedback control strategy.
Document ID
19870063188
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Bryson, Arthur E., Jr. (Stanford University CA, United States)