Solar powered electric propulsion orbit transfer vehicle design and operational effectiveness

The feasibility and cost effectiveness for using solar powered electric propulsion orbit transfer vehicles (EOTV) to move Block 3 NAVSTAR Global Positioning System (GPS) satellites from LEO to a 10,900 nm orbit were determined. The electric propulsion systems considered were present and 1990's technology ion engines using mercury, xenon or argon for a propellant. A systems cost model which combines payload, power sources, trajectory, and earth-to-LEO launch parameters with algorithms characterizing the electric propulsion system was used. The least costly systems which had a triptime equal to or less than 90 days were determined. These systems were then compared with the PAM D-II, Centaur-G, and IUS in terms of total deployment costs for 28 GPS satellites launched at a rate of four per year for seven years. The study found that a reusable EOTV with 12 mercury ion engines powered by gallium arsenide concentrator arrays could perform the mission for 57 percent of the cost of the cheapest chemical system.