Actuator rate limiting has been linked to the occurrence of pilot-induced oscillations (PIOs). Evidence from many of the events suggests that the airplanes were prone to PIOs before rate limiting was experienced. There is a lack of experimental data to determine if rate limiting causes PIOs, or to what extent it contributes to severity of PIOs. This paper presents the results of a limited flight test investigation of PIO due to elevator rate limiting. Three aircraft dynamics, seven rate limits, and two Head-Up Display (HUD) tracking tasks were evaluated on the US Air Force NT-33A variable stability aircraft by three pilots. The results show that: 1) for airplanes that possess inherent PIO resistance, even the most severe level of rate limiting does not consistently lead to PIO; 2) addition of forward-path filters increases the susceptibility to PIO; and 3) use of augmentation to stabilize a highly unstable design can lead to rapidly divergent PIOs when rate limiting is encountered.
A flight investigation of pilot-induced oscillation due to rate limiting
1998 IEEE Aerospace Conference Proceedings (Cat. No.98TH8339) ; 3 ; 59-74 vol.3
1998-01-01
1331888 byte
Conference paper
Electronic Resource
English
A Flight Investigation of Pilot-Induced Oscillation Due to Rate Limiting
British Library Conference Proceedings | 1998
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