50 Estimating assembly time: We assume a launch capacity of two per week or 104 per year. At this rate, it takes just over 6 weeks for 13 Starships to reach orbit. We therefore assume it takes 7 to 8 weeks for one payload-laden Starship to be fully refueled in LEO. We assume that no cryogenic boil off occurs in orbit. Given the variable possible conditions of launch sites and orbits, we assume that one additional month of travel time to GEO is more than sufficient. We assume 4,200 m/s is more than sufficient for a chemical propulsion orbital transfer from LEO to GEO. Applying known inputs to delta v and transit time equations (below) yields delta v well in excess of this minimum. For Starship, we use 355 s, 14.7 MN, a payload mass of 100 MT, fuel mass of 120 MT, and dry mass of 100 MT. Delta V = specific impulse * standard acceleration due to gravity * natural logarithm (initial mass/final mass) Transit time = (initial mass / thrust) * deltaV / specific impulse Number of modules in GEO = (this month’s number of payloads in GEO - previous month’s number of payloads in GEO) * maximum number of modules on Starship - ((number of servicers in GEO this month - number of servicers in GEO last month) * servicer mass) / module mass + number of modules in GEO last month Modules assembled per month = number of servicers in orbit * servicer monthly assembly rate Finally, the cumulative number of modules assembled was evaluated at each month to maximize the efficiency of the servicer fleet by minimizing servicer idle time. We use Aerospace’s assessment that servicers will take approximately 40 and 38 minutes to assemble a single RD1 and RD2 module, respectively. Our assembly timeline model seeks to minimize servicer downtime during construction phases. Our first order model estimates 7.4 and 12.6 years to assemble RD1 and RD2, with 17 and 15 servicers, respectively. In both cases, no servicer is idle until the final year of assembly operations. Estimating costs for Mission Operations & Data Analysis – Assembly: Aerospace assessed the operation of the ADR fleet as autonomous, common to any fleet size, and at a rate of $300k/month. For the more complex task of assembling the SBSP system itself, we assume four times this cost, or $1.2M/month. This number is informed by analogs like Starlink (Johnson & Roulette, 2018), assuming one sixth of the Starlink workforce (50/300), assuming capital costs for labor ($18,000/month) and adding the result ($900k/month) to Aerospace assessed cost of operating an autonomous fleet. ConOps Phase 3: Operate Operate Components: • Construct ground facilities • Perform mission operations and data analysis to operate during service lifetime
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