Rotary-wing vehicles proposed for improved system capacity must meet civil global aviation requirements for safety, efficiency, and affordability. To achieve the needed advances, greatly improved modeling is required. Many advances have been made in measuring dynamic characteristics of rotary-wing vehicles, for example by Tischler et al. However, innovative advances are needed in methods to capture the dynamic and cross-coupling effects that are still a challenge and impediment to rapid design cycles. A very recent advance in test techniques utilizes water as a test medium for dynamic testing. This method circumvents many of the problems presented by air as a medium, by allowing testing in slow motion, by separating model and test support frequencies, by greatly improving signal-to-noise ratios, and by allowing the traditional advantages of the familiar water tunnel or channel, with its unparalleled flow visualization. POTENTIAL COMMERCIAL APPLICATIONS The ability to predict maneuvering aerodynamics and stability parameters early in the development cycle will reduce the time, risk, and cost of new rotorcraft. The methods described herein also apply to high performance aircraft development
