Radiation analyses were performed and shielding weight requirements were estimated for various candidate vehicle and payload configurations for use with the reusable nuclear shuttle. The analyses included both point kernel and Monte Carlo approaches. The effects on reduced shield weight were determined for propellant ranks with pointed conical tank bottoms and for one case of a cluster of small tanks. This later case, however, had an arrangement which had no center tank in the upper tier of tanks. This effect negated most of the gain of going to the smaller tanks. A range of shield weights is presented for various light and heavy manned payload configurations when used in conjunction with a single liquid hydrogen propellant tank, 33 ft in diameter with a 15 deg conical tank bottom
