Composite Cryogenic Technologies and Demonstration Project
The objective of the Composite Cryogenic Technologies and Demonstration project (CCTD) is to advance the technologies required to develop lightweight composite cryogenic propellant tanks applicable to heavy-lift launch vehicles, propellant depots, and future lander systems.
Success in this project could lead to rocket propellant tanks that are more than 30% lighter and 25% cheaper to fabricate compared to the current state-of-the-art metallic tanks. Such advancements offer less cost for payload delivery to orbit and the potential of enabling advanced human and robotic space exploration missions.
The concept being developed and demonstrated by this project involves advanced materials (composites), structural concepts (joints, splices, fasteners, etc), and manufacturing techniques. Generally, the manufacture of high performance composite structures requires the use of an autoclave, which is a large pressure vessel in which high temperature and pressure needs to be accurately controlled during the fabrication process. The disadvantages associated with an autoclave system are that it limits the size of the composite structure being manufactured, and for very large composite structures, the autoclave vessel would be very expensive to build. For this project, an out-of-autoclave manufacturing approach is being developed. If successful, the manufacturing of large high performance composite structures can be accomplished throughout industry without the need of an autoclave thus improving competition and potentially further reducing the cost to manufacture very large components.
An accelerated building block approach, focused on achieving affordability and technical performance as verified through agreement between experimental and analytical predictions, is being followed for this project. Initially, composite panels followed by a 2.4 meter (7.9 feet) diameter tank will be designed, manufactured, and tested using the selected procedures. With the issues and risks minimized, a 5.5 meter (18 feet) diameter tank based on the loading environment predicted for a full scale (8.4 meter -- 27.6 feet -- diameter propellant tank) will be designed, manufactured, and tested in a relevant loading and temperature environment.
During FY2011, NASA and four industry partners developed conceptual designs for a 10 meter (32.8 feet) diameter composite cryogenic tank with a goal of significantly reducing the weight and cost from current state-of-the-art aluminum-lithium tanks. These designs included material trades and structural loads analyses, as well as manufacturing trades, autoclave versus out-of-autoclave options, tooling, manufacturing and facilities, and inspection and repair. Results from these studies identified critical features and high-risk issues associated with large cryogenic composite tanks. In September 2011, The Boeing Company in Huntington Beach was selected by NASA as the prime contractor for this 2+ year project.
The project is managed at Marshall Space Flight Center (MSFC) and is supported by subject matter experts from Glenn Research Center, Kennedy Space Flight Center, Langley Research Center, and MSFC.