Through the proposed NASA SBIR program, NanoSonic will optimize its HybridSil® derived yttrium silicates to serve as next-generation reinforcement for carbon and ceramic felt ablative TPS materials. This effort will leverage NanoSonic's rapidly evolving polymer derived ceramic technology, which has demonstrated thermomechanical durability in excess of 1900 oC, thermal conductivity as low as 30 mW/mK, erosion resistance to high velocity sand, and facile spray depositability under ambient conditions. NanoSonic's yttrium silicate TPS reinforcing matrices will be molecularly engineered to drastically outperform current char-forming carbon / phenolic materials during planetary entry while weighing and costing less by providing nanocomposite matrices with substantially enhanced 1) thermo-oxidative durability, 2) impact resilience, and 3) readily tailorable high temperature ablative recession rates . The driving optimization factors for phase I TPS materials will include interfacial covalent coupling to surface functionalized carbon and ceramic felts, bulk morphology of the host matrix, and composition of the yttrium silicate polymorph. Thermal loading on promising TPS materials simulating current and future Exploration missions will be completed by the University of Washington's high enthalpy test facility. In support of a phase III transition, NanoSonic has generated significant defense prime interest and has an established pilot scale HybridSil® manufacturing infrastructure.