Experimental evaluation of superposition techniques applied to dynamic aerodynamics

Abstract

Aerodynamic models used to predict the behavior of aircraft during maneuvers, such as those used in a flight simulator, are typically built from wind tunnel test data, mathematical estimations and computational fluid dynamic calculations. It is impractical to test all possible maneuvers, including various rates, amplitudes, and orientations. Historically, only a small subset of these combinations has been tested, and the results are interpolated or extrapolated to estimate the behavior in untested regions. A typical wind tunnel test program may include forced oscillation testing in pitch, roll, and yaw to obtain damping derivatives and rotary balance testing to investigate spin damping. One way of combining these data-sets into a single math-model is a vector interpolation scheme originally proposed by Juri Kalviste. The current work seeks to determine experimentally where this type of vector interpolation is valid, and where it becomes less accurate. The current work reports on the first phase of this work, which is to ensure that the experimental system has the accuracy required by validating it at low angles-of-attack, in the linear region. © 2002 by Eidetics Corporation.