Using Commercial Launchers and Fuel Depots Instead of HLVs

Near Term Space Exploration with Commercial Launch Vehicles Plus Propellant Depot, Dr. Alan Wilhite and Dr. Douglas Stanley, Dale Arney and Chris Jones, GRAs Georgia Institute of Technology/ National Institute of Aerospace

"The Propellant Depot Hypotheses

* Large in-space mission elements (inert) can be lifted to LEO in increments on several medium-lift commercial launch vehicles (CLVs) rather than on one Heavy Lift Launch Vehicles (HLLVs)
* The heavy in-space transportation mission elements are beyond the payload capability of medium-lift CLVs; however, 80 to 90 percent of their mass is propellant that can be delivered in increments to a Propellant Depot and transferred to the in-space stages
* Saves DDT&E costs of HLLV
* Low-flight-rate HLLV dominated by high unique fixed costs. Use of CLVs eliminates these costs and spreads lower fixed costs over more flights and other customers.
* Use of large re-fueled cryo stages save DDT&E/ops costs for advanced propulsion stages (e.g., SEP)"