Patent Number: 
Section: claims

1. A method comprising:arranging a shipping container comprising a tubular or cylindrical shell having a closed end, an open end, and elastomeric sidewalls into a vertical orientation in which the tube or cylinder axis of the cylindrical shell is oriented vertically with the closed end oriented down and the open end oriented up;loading an unirradiated nuclear fuel assembly comprising 235U enriched fuel through the open end of the tubular or cylindrical shell into a fuel assembly compartment defined inside the tubular or cylindrical shell; andafter the loading, closing off the open end of the tubular or cylindrical shell by securing the top end-cap to the open end of the tubular or cylindrical shell,wherein the loading causes compression of the elastomeric sidewalls of the fuel assembly compartment. 2. The method of claim 1 further comprising:after the closing off, rearranging the shipping container into a horizontal orientation;after rearranging the shipping container into the horizontal orientation, arranging the shipping container back into the vertical orientation in which the tube or cylinder axis of the cylindrical shell is oriented vertically with the closed end oriented down and the open end oriented up;removing the end-cap to re-open the open end of the tubular or cylindrical shell; andunloading the unirradiated nuclear fuel assembly from the fuel assembly compartment through the re-opened open end of the tubular or cylindrical shell. 3. The method of claim 1 wherein the shipping container includes N fuel assembly compartments defined inside the tubular or cylindrical shell where N is greater than or equal to two, and the loading is repeated N times to load N unirradiated nuclear fuel assemblies into the N respective fuel assembly compartments.