In previous research, an aircraft trajectory planning algorithm was developed aiming at optimizing continuous descent operations with required times of arrival at given waypoints. A non-linear optimal control problem was solved by using direct transcription methods. In this paper, enhanced models for the same optimization framework are presented, im- proving the accuracy of the optimized trajectories. These new models take into account wind, realistic atmospheric conditions, curved trajectories and general improvements in the aircraft dynamics model. Preliminary results are shown in a hypothetical scenario where trajectories are optimized from cruise altitude to the runway with different required times of arrival at the threshold. The effects of wind and non-standard atmospheres can be easily appreciated.