V-22 Three-Dimensional (3D) Downwash Measurement Navy SBIR FY2009.1 Sol No.: Navy SBIR FY2009.1 Topic No.: N091-029 Topic Title: V-22 Three-Dimensional (3D) Downwash Measurement Proposal No.: N091-029-1217 Firm: Southwest Sciences, Inc. 1570 Pacheco Street, Suite E-11 Santa Fe, New Mexico 87505 Contact: David Hovde Phone: (513) 272-1323 Web Site: http://www.swsciences.com Abstract: The Navy requires measurements of the wake field of helicopters in the vicinity of carrier ships to determine the safe operating envelope for the V-22 and to verify the accuracy of models obtained by computational fluid dynamics. This Phase I SBIR project will examine the feasibility of a laser-based remote sensing technique for recording three dimensional wind fields with high spatial and temporal resolution. A laser beam shines across the flight deck, where some of the light scatters from aerosol particles in the air to a group of at least three optical detectors placed around the measurement region. The motion of the particles encodes information about the wind velocity as a change in frequency of the scattered light. An innovative optical filter converts the frequency information into a signal that is proportional to velocity. The optical filter is simple, inexpensive, and has a wide acceptance angle, permitting the use of fast optics to collect the most light possible. The high signal to noise ratio obtained by this technique allows measurements from stand-off distances of over twenty meters using low-power lasers. Other system features include low electrical power and compact transmitter and receiver assemblies that should facilitate onboard tests. Benefits: This research will lead to Phase III testing for the Navy to allow safer operation of multiple aircraft around carriers. Significant commercial applications include wind field measurements at airports and wind farms. Return