The paper points out potential shortcomings of the coupled-proportional guidance-based glide slope capture, and proposes a more generalized expression for this method. Furthermore, an analysis of possible feedback measurement errors is conducted, and an adaptive tunning approach for key control parameters in the control law is proposed. Analysis and simulation results show that the normalization of feedback quantities in the control laws avoids the influence of linear errors on control effectiveness, and the adaptive parameter design demonstrates that more ideal capture trajectories can be achieved.