CERTAIN PORTIONS ARE ILLEGIBLE , IT IS BEING RELEASED IN THE INTEREST OF MAKING
A review of the factors affecting the helicopter market for the past, present, and future is presented. The trade-offs involving acquisition cost, mission reliability, and life-cycle cost are reviewed, including civil and military aspects. The potential for advanced vehicle configurations with substantial improvements in energy efficiency, operati.ig economics, and characteristics to satisfy the demands of the future market are identified. Advanced propulsion systems required .o support these vehicle configurations are, in turn, discussed, as well as the component technology for the engine systems. Considerations for selection of components in areas of economics and efficiency are presented.
Development of Sprayed Ceramic Seal System for Turbine Gas Path Sealing
A ceramic seal system is reported that employs plasma-sprayed graded metal/ceramic yttria stabilized zirconium oxide (YSZ). The performance characteristics of several YSZ configurations were determined through rig testing for thermal shock resistance, abradability, and erosion resistance. Results indicate that this type of sealing system offers the potential to meet operating requirements of future gas turbine engines.
Flight Test Evaluation of the High Inertia Rotor System
Abstract : The objectives of this program were to document the reduction in height-velocity restrictions for autorotational landings, the increased transient performance and maneuver capability using modified flight techniques, and the handling qualities of a modified OH-58A helicopter with a High Energy Rotor System (HERS). The rotor incorporated increased chord blades and provision for three different tip weights resulting in Lock number variations of 2.61, 3. 14, and 5.43.