WL-TR-96-3028, TECHNICAL REPORT: UNIFIED PILOT-INDUCED OSCILLATION THEORY - VOLUME 1; PIO ANALYSIS WITH LINEAR AND NONLINEAR EFFECTIVE VEHICLE CHARACTERISTICS, INCLUDING RATE LIMITING (DEC-1995)

WL-TR-96-3028, TECHNICAL REPORT: UNIFIED PILOT-INDUCED OSCILLATION THEORY - VOLUME 1; PIO ANALYSIS WITH LINEAR AND NONLINEAR EFFECTIVE VEHICLE CHARACTERISTICS, INCLUDING RATE LIMITING (DEC-1995)., This work was conducted as part of a USAF initiative to develop a comprehensive theory to predict pilot-induced oscillation (PIO) tendencies due to the combined effect of all influencing elements. A PIO is a very complicated phenomenon stemming from a dynamic interaction between the pilot and the aircraft. When tight control is required from the pilot, an undesired oscillation can result. However, the adap- tive nature of the human pilot makes such oscillations difficult to predict. The independent research of STI included: Compilation of available PIO time histories and references as an initial step toward a comprehensive PIO database; refinement of the proposed PIO categories defined in NASA CR-4683; development of PIO theories based on these categories; development of methods to handle the higher frequency and nonlinear aspects of PIO analysis with an emphasis on rate limiting; and a review of existing and proposed linear PIO criteria.