LEO/GSO cyclic depot transfer

This paper investigates the development and use of semi-analytic methods for propellant depot orbit selection in cyclic, coplanar, Keplerian GSO missions. The cyclic depot transfer strategy which allows for non-optimum (e.g. non-Hohmann) transfer, is constrained by resonance requirements allowing for descent rendezvous/refueling with fuel depots positioned during the ascent phase of the mission. The mission benefit using this transfer technique allows an improvement in propulsion system efficiency which can lead to approximately 43 percent reduction in initial launch mass when compared to traditional methods, but with the trade-off of longer mission timelines. A family of potential transfers is identified with an 'optimum' selection not based on conventional delta V minimization. The results of this analysis include reduced transfer times and greater potential initial launch mass savings over previous work.