CIRCLE-TO-CIRCLE CONSTANT-THRUST ORBIT RAISING

This paper provides simple graphical/analytical tools to determine the minimum elapsed time and associated fuel of a constant-thrust vehicle transferring between coplanar circular orbits. The rocket equation mo dels the effects of continuous fuel expenditure while also serving to recast the solution in terms of accumulated velocity change. These orb it-raising solutions are globally mapped with no restrictions on initi al thrust magnitude, intermediate eccentricity, or number of revolutio ns of the central body. Several examples are presented to verify the t ransfer charts/equations and familiarize the reader with their use. Th ese are useful tools for mission planners and satellite designers to a ssess preliminary fuel requirements and transfer times for constant-th rust systems. They are also good for performing propulsion trade-off s tudies for various missions. A straight-edge and scientific calculator are the only tools needed.