ORBITEC proposes to develop and demonstrate an Integrated Composite Rocket Nozzle Extension (ICRNE) for use in rocket thrust chambers. The ICRNE will utilize an innovative bonding approach to join a high-temperature composite nozzle extension to a regeneratively cooled metallic nozzle. The ICRNE technology will allow high-temperature composite materials to be directly integrated into a regeneratively-cooled nozzle section or thrust chamber made out of high-strength metallic alloys, thereby eliminating the heavy bolted flange joint that is currently used to attach high-temperature nozzle extensions. The resulting weight reduction will increase the thrust-to-weight ratio of the rocket engine. The ICRNE will also eliminate the need for multiple seals in the bolted flange joints, thus increasing reliability. The focus of the proposed Phase 1 effort will be to demonstrate the ICRNE technology by manufacturing and evaluating test specimens. A prototype ICRNE will also be designed and analyzed. In Phase 2, a prototype ICRNE unit will be fabricated, installed, and hot fire tested on an existing rocket engine. This proposal responds to Subtopic H2.02 In-Space Propulsion Systems, specifically "high temperature materials, coatings and/or ablatives or injectors, combustion chambers, nozzles, and nozzle extensions" for non-toxic, cryogenic, and nuclear thermal propulsion systems.