Demonstration of the Microwave Ice Protection Concept
Final rept. Jun 1976-Jun 1977
MECHANICS RESEARCH INC MCLEAN VA
Pagination or Media Count:
An experimental demonstration of the microwave ice protection concept for helicopter rotor blades is presented. By shedding ice samples from experimental ice protection devices, microwave ice protection theory was verified. Increased power density in the ice layer is achieved by operating at higher microwave frequencies, resulting in significantly shorter shed times for the same microwave power. The microwave concept offers the possibility of constructing ice protection systems totally out of nonmetallic materials that will not deteriorate the radar cross section of composite blades. Incremental weight, cost and power estimates for equipping various helicopters are presented. An evolving microwave tube technology promises significant improvements in cost, efficiency, weight, and power drain while providing higher microwave powers and consequently shorter shed times. It is demonstrated that a combination erosion shieldsurface waveguide constructed from ultrahigh molecular weight polyethylene UHMWPE fortified with a layer of polyurethane near the tip did not deteriorate the mean time between unscheduled maintenance MTBUM of the blade below that of the polyurethane erosion shield by itself. When the erosion shieldsurface waveguide reaches the MTBUM it can be replaced without discarding the blade.
- Electrical and Electronic Equipment