This thesis presents variable span wing morphing (VSWM) as an effector of roll control for unmanned aerial vehicles (UAVs). In this study, the roll coefficients obtained from VSWM are quantified by theoretical and experimental data and compared with typical aileron roll coefficients. We see that small changes in span are an effective alternative to conventional ailerons for producing roll. The standard six-degree of freedom (6-DOF) model that describes aircraft dynamics is revisited. We derive and examine the extra inertial terms that morphing introduces into the moment equations of the 6-DOF model. In this thesis, we derive simple expressions for these additional terms. In particular, we are able to extract a single degree of freedom model by considering the case of a pure roll. This model describes the dynamics of an aircraft executing a pure roll by means of span morphing. The critical distinction between the well-known aileron model and the span model derived in this thesis is clear. The span model contains an additional term whose behavior tends to modify the total damping.