Flights to the Moon are compounded by the need for a Cislunar Vehicle (CV) to make the trip there and back. Each CV demands six Space Shuttle Reentry Vehicles (RVs) to complete its sortie: one to bring up the lunar payload, and five to refill the CV propellant tanks.
We also need to replenish the reagents used to generate Liquid Oxygen (LO2) on the Moon, requiring even more RVs and more propellant for the CVs.
Table 1 provides a breakdown of the 94 RV flights needed for lunar operations.
Kindly note that the majority of Space Shuttle flights devoted to lunar ops (85.1%) is rocket propellant.
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