An evolutionary GEO transportation system

Several transportation system options that utilize the Space Station as a base for delivery of payloads to geosynchronous earth orbit are examined and compared to each other as well as to the reference case, which uses the orbiter as the staging base. The factors evaluated include impact on Kennedy Space Center (KSC) flow, STS traffic, load factor, and the cost effectiveness of each transportation system option. With respect to KSC flow, it is determined that utilizing the Space Station as a staging base could lead to a reduction of 3000 man-hours off-line and an additional 475 man-hours on-line. Launch costs for STS are reduced by 10 percent. The actual number of STS flights varies depending on the transportation system option, and the delivery of multiple payloads results in the least cost.