Applications of Flight Control System Methods to an Advanced Combat Rotorcraft.

摘要

Advanced flight control system design, analysis, and testing methods are applied in an analytical and flight test evaluation of the Advanced Digital Optical Control System (ADOCS) demonstrator. This paper describes the knowledge gained about the implications of digital flight control system design for rotorcraft, and illustrates. The analysis of the resulting handling-qualities in the context of the proposed new handling-qualities specification for rotorcraft. Topics included are digital flight control design and analysis methods, flight testing techniques, ADOCS handling-qualities evaluation results, and correlation of flight test results with analytical models and the proposed handling-qualities specification. Evaluation of the ADOCS demonstrator indicated desirable response characteristics based on equivalent damping and frequency, but undesirably large effective time-delays. Piloted handling-qualities are desirable or adequate for all low, medium, and high pilot gain tasks; but handling-qualities are inadequate for ultra-high gain tasks such as slope and running landings. Correlation of these results with the proposed handling-qualities specification indicates good agreement for the bandwidth boundaries, but suggests the need for more stringent limits on allowable phase-delay. Analytical models based on emulation (s-plane) techniques compare favorably with flight extracted frequency-domain characteristics of the overall (end-to-end) ADOCS responses. Direct digital analysis procedures are necessary to characterize the intersample behavior of the actuator rate response. (EDC)