Due to the relative expense of the orbital plane-change maneuver when it is accomplished by means of impulsive thrust, other techniques have been sought that would be more economical from the standpoint of required characteristic velocity. Two techniques that make use of combined aerodynamic and propulsive forces have been proposed by London and Nyland. These are reviewed, and their limitations, which are due in part to certain simplifying assumptions made in their analyses, are presented. This investigation demonstrates that both analyses, while valuable because they are presented in closed form, are limited to plane changes below 30 to 40 degrees. It is also shown that the combined maneuver is superior to the impulsive-thrust plane change for vehicles with lift-to-drag ratios greater than 1.5 and that the velocity savings that result as a consequence of using such maneuvers are on the order of 4000 to 5000 ft/sec, at most. As a result, it is concluded that, for certain situations, the combined aerodynamicpropulsive maneuver appears to be an attractive and available means for reducing the characteristic velocity requirement of the orbital plane change.