Frequency-response Identification of XV-15 Tilt-rotor Aircraft Dynamics PDF Download

Author: Mark B. Tischler
Publisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 200

Get Book Here

Book Description
Timely design and development of the next generation of tiltrotor aircraft (JVX) depend heavily on in-depth understanding of existing XV-15 dynamics and the availability of fully validated simulation models. Objects of the present study are: 1. Documentation and evaluation of XV-15 bare-airframe dynamics; 2. Comparison of aircraft and simulation responses; and Development of a validated transfer-function description of the XV-15 needed for future studies. A nonparametric frequency-response approach is used which does not depend on assumed model order or structure. Transfer-function representations are derived which fit the frequency responses in the bandwidth of greatest concern for piloted handling-qualities and control-system applications. Flight tests on the VX-15 aircraft and piloted-simulation for four flight conditions from hover to cruise were planned and executed. Improved test techniques and pilot-training procedures were devised. Analytical software tools allow the identification of high-resolution spectural responses and the derivation and validation of multi-input/multi-output transfer-function models. These techniques were applied in an extensive evaluation of the open-loop flight dynamics of the XV-15 aircraft and simulation mathematical models. Deficiencies in the mathematical models were exposed and documented.