Composite Boss System Concepts

This Phase II SBIR program accomplished a review of ten composite boss designs and reduced them to three concepts. This program will perform detailed design and development and a demonstration test of the three selected concepts and may further downselect to two or one final designs. The key factors in this program are the evaluation of sealing methods and the demonstration of fastening concepts to incorporate boss attachment rings and closures into concept tanks and also composite motor cases. Theprogram will test an existing design as a baseline concept to verify the existing pressurized seal design. Available sealing methods against pressure and temperature will be compared to establish optimum sealing methods.Two tanks will be fabricated using either one or two optimum designs. One of these tanks will be tested using liquid helium to verify the sealing capability. The second tank will be provided to the Air Force for evaluation. Finally, the selectedcomposite boss concept will be adapted into a motor case design for attachment rings for the igniter and the nozzle and throat system. If feasible the motor case attach ring concepts will be bench tested and tooling will be designed and fabricated.