SPS Feasability Study SD76SA0239-2

4.3 CREW AND RESUPPLY MODULE In Section 3 a construction sequence was developed that required a crew rotation every 90 days for crew complements in multiples of 48. A crew and resupply module (CRM) was synthesized on this basis. Based on previous studies of passenger modules for an orbiting lunar station, lunar surface base, geosynchronous station, and LEO space station, a parametric sizing curve for passenger modules was developed (Figure 4.3-1). These data indicated that for a crew complement of 48 persons, the module would weigh approximately 200 kg (440 lb) per man, or 9,600 kg. Comparable data were extracted from these studies for consumables, passenger/personal effects, in-transient consumables, crew module, resupply module, and on-orbit habitable module spares. The resultant logistics profile for a 48-man contingent at geosynchronous orbit for 90 days is presented in Table 4.3-1. Table 4.3-1. Crew Rotation/Resupply Logistics Profile A conceptual layout of the CRM is shown in Figure 4.3-2. It was assumed that a command module area would be required to monitor and control OTV performance during crew rotation flights. This function was incorporated in the forward section of the passenger module as shown. Spacing and layout of the passenger module is comparable to current commercial airline practice. A nominal packing density of 160 kg/m^ (10 lb/ft^) was assumed for resupply consumables. It was assumed the resupply modules would be exchanged each mission. While at GSO, the resupply module could be used as the consumables storage module. Thus, multiple access aisles also were included in the sizing of the resupply module. A gross packing density of 93 kg/m^ (6 lb/ft^) resulted, which allows for a large growth factor.