Reduced mass composite materials are crucial to the success of aerospace systems, but their adoption is inhibited because they require autoclave consolidation, a process that is prohibitively expensive for large aerospace structure. To remedy this, NASA-LaRC has been developing cost-effective high-performance thermoplastic composite processing equipment that enables out-of-autoclave tape placement. In particular, NASA is working with Accudyne Systems to install a heated in situ deposition placement head to fit on NASA-LaRC's placement machine. This SBIR is to create the optimal composite material feedstock to go hand-in-hand with the thermoplastic process equipment so as to create desirable mechanical and physical properties in a part with out-of-autoclave in-situ placement. Accudyne Systems will define the matrix resin and fabricate thermoplastic tape to create the ideal in situ processible material. The first approach will be to proveout a fully amorphous composite based upon NASA 8515. This avoids the undesirable kinetics of a semi-crystalline thermoplastic like PEEK. The second approach will be to use POSS nanoparticles in semi-crystalline PEEK to accelerate crystallinity to the short time scale of the in situ process. The best options will be commercialized to allow NASA and aerospace primes to fabricate low-cost large composite structure for air and space transport.