Control Space Analysis of Three-Degree Decelerating Approaches at Amsterdam Airport Schiphol

Amsterdam Schiphol Airport currently uses a Continuous Descent Approach during night time operations only, due to reduced runway capacity caused by unpredictable individual aircraft behavior. The Three-Degree Decelerating Approach (TDDA) has been developed to increase predictability and runway capacity by switching the sepa- ration task from Air Traffic Control to the pilot on board the aircraft. The research described in this paper identifies the factors that influence the control space of aircraft performing a TDDA in a real-life setting. Control space is defined as the difference between the maximum and minimum duration to perform the TDDA. Using different control strategies, a fast approach or slow approach can be flown. A fast-time simulation tool was built to perform simulations with different aircraft types, initial weights, wind speeds and directions. Preliminary simulations indicate that a flap scheduler is needed to optimize control space, and the flap scheduling algorithm was enhanced to find optimal flap schedules for all wind conditions. The results of these simulations show that the influence of wind direction depends on aircraft aerodynamic characteristics, which mainly depend on the drag characteristics of the aircraft and aircraft weight. Furthermore, the results can be used to determine whether a TDDA can be executed using different aircraft and under different wind conditions