GTE Laboratories has been supporting Allison Gas Turbine Division of General Motors under the current ATTAP program since early 1988. Injection-molding process development and component fabrication has been the emphasis of this effort, but material property enhancement studies have also been an important complement. Attempts to increase the resistance to foreign object damage have been made through parallel investigations of microstructural control and SiC whisker reinforcement. The research activities aimed at improving fracture toughness of GTE PY6 Si3N4 are discussed.