Rapidly Adjustable Nonmetallic Rotor Blade Tracking Tab

This proposed program will develop a rapid trimming device that will permit a nonmetallic trim tab to be quickly and accurately positioned. Enabling a rapid trimming technique will decrease blade tracking timer simplifying the procedure and enabling the accuracy and turnaround of metal trim tabs. Foster-Miller will use a combination of ultrasonic heating and design modifications to develop a technique for positioning the Comanche trim tab. The ultrasonic system will eliminate the trim fixture as a thermal mass and will increase the heat transfer into the trim tab. Both factors, coupled with nearly instantaneous heating with ultrasonics, will decrease the blade tracking time to that needed to position the fixture and mechanically bend the tab. Long wait times for tab heating and cooling will be eliminated. Foster-Miller will work with both the Boeing Helicopter Division of the Boeing Defense and Space Group and with Sikorsky Aircraft. These companies are the primes on the Comanche program and will ensure a realistic and cost-effective solution to the problem. A Phase II program is anticipated to develop a production ready trim bend fixture. Foster-Miller will work closely with Boeing to integrate ultrasonics into their existing fixture to decrease blade tracking cycle time. The Phase I program will develop techniques for rapidly trimming rotor blades with nonmetallic trim tabs. This is an essential blade feature for future military helicopters. The technology is also applicable to a variety of areas such as repair of composite structures using low cost ultrasonics.