The skirt that supports a composite-overwrapped tank would be made an integral part of the composite overwrap, according to a proposal. In current practice, the structure that supports a composite-overwrap tank usually includes a layer of rubber between the tank and its skirt. The rubber layer is heavy and constitutes a relatively weak link in the tank-supporting structure.
The proposal arose from an investigation of how to reduce the weight of the tank and its supporting structure, considering the tank as part of an overall tank/structure system. The investigation revealed that elimination of the rubber layer could reduce the weight of the system considerably.
The fiber reinforcement in the skirt would be filament wound directly onto the tank, without an intervening layer of rubber. The weight of the tank/structure system would be reduced and the strength of the skirt/tank bond increased accordingly, and the skirt would bear part of the hoop stress of the tank.
This work was done by Joseph C. Lewis of Caltech for NASA's Jet Propulsion Laboratory. No further documentation is available. NPO-20455