TiltRotor Aeroelastic Stability Testbed (TRAST) Test and Modeling Data

Author(s):

Andrew Kreshock, Robert Thornburgh, and Hao Kang

Abstract:

This report is intended to provide TiltRotor Aeroelastic Stability Testbed (TRAST) model data and test data for understanding the tiltrotor whirl-flutter stability mechanism and for analytical model development and validation. The TRAST model is a semi-span wind tunnel test system designed to test dynamically scaled proprotors in the NASA Langley Research Center Transonic Dynamics Tunnel. The TRAST parameters—including blade flap-pitch couplings (delta-3), pylon pitch spring stiffness, and pylon yaw (diaphragm) stiffness—are adjustable so the effects of control system geometry and wing/pylon dynamics on whirl flutter of the rotors and wings can be investigated experimentally. The TRAST model data includes geometry definition and the structural, inertia, and aerodynamic properties. The test data include ground vibration test data and whirl-flutter stability test data. To support the development of the analytical models for tiltrotor aircraft whirl-flutter analysis, a set of comprehensive analysis models for TRAST whirl-flutter stability predictions are also provided.