RF Guidance Sensor Windows for High-Speed and Hypersonic Air Vehicles

Advanced Cerametrics, Inc (ACI) has developed a new ceramic material to compete directly with the very high priced reaction bonded silicon nitride (RBSN) and obsolete Pyroceram radomes. ACI has built on earlier work done by NAVSEA to develop a repeatable and inexpensive process to produce radomes from Barium Alumino Silicate (BAS) using high temperature eutectic BAS fiber as a reinforcement for the BAS matrix ceramics and then, in order to make a sandwich structure, backfilling with an aluminum phosphate coating for erosion resistance and dielectric enhancement. These window materials must withstand temperature rises to > 1300 0 C in a few seconds, while being electronically compatible with missile systems and erosion resistant to Mach 6 raindrops. Very few materials meet these criteria. BAS has been shown to be an acceptable candidate and the proposed work will continue qualification of the material ongoing from the Phase I and an earlier program, while optimizing its properties in actual radome structures. The DOD prime supports this program fully and will cooperate every step of the way to get these new window materials qualified and in use in the fleet as soon as possible. Full size radomes will be built, based on data provided by ACI cooperative partners, and these will be evaluated to prepare for real time testing by the end of this Phase II effort. Project goals include building full scale radomes at less than 1/10 the cost of RBSN, yet within the operational parameters required of hypersonic missiles.