Thin film Metal RubberTM sensor appliqus have the potential to reduce
the time, complexity and cost of measuring air flow-induced skin
friction during the development of rotary wing and fixed wing aircraft
and related systems.  Metal Rubber&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
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 skin friction sensor appliqus allow near real-time detection 2D mapping
of air flow conditions over surfaces of air vehicles.  This is important
for analysis of laminar to turbulent flow transitions, flow separation
and reattachment mechanisms, and other instabilities, during rotor blade
and fuselage design, blade tracking adjustments, and active flight
control.  The sensors act as mechano-electrical transducers to convert
air flow-induced tangential surface forces into electrical output
signals.  They are thin and surface-mounted so cause minimal interaction
with the flow, are easy to apply as an appliqu, and require no cavities
or recesses other than holes to connect the sensor leads to data
acquisition wiring.  The material is resistant to normal aircraft fluids
and solvents, can operate over a temperature range of -65 to +150C, and
is capable of withstanding moderate rain and dust erosion.   During
Phase II, NanoSonic will  Develop an improved understanding of the
operation of thin film Metal RubberTM skin friction sensors,
Standardize sensor design and sensor fabrication processes,  Develop a
method to calibrate sensor elements as part of manufacturing,  Develop a
means to compensate for cross-sensitivity effects,  Develop and optimize
means for data acquisition,  Use developed sensors in cooperation with
the NASA LaRC Subsonic Rotary Wing program to investigate rotorcraft
research and development problems, and  Use and demonstrate the sensors
in cooperation industry and academic colleagues. The significance of the
proposed NASA Phase II SBIR program is in transitioning these sensors
from analytical and FEM modeling to commercial products for experimental
use by NASA and industry.