Typical additional spacing-buffer to apply at 4DME for delivering separation minima

Currently, at many airports, the runway is the limiting factor for the overall capacity. Among the most important parameters are the wake turbulence separation minima expressed in distance and the differences in speed profile between the leader and follower aircraft for arrivals on final approach that limit the arrival flow at many airports in Europe [1]. For dealing with these limitations ATCOs take a (fixed) buffer into consideration based on training and experience for ensuring minimum separation. However, research has shown that above described experience can be quantified for facilitating delivery of optimum operations. Therefore this paper presents the additional spacing for the follower aircraft when the leader is at 4DME for delivering the minimum distance separation. This paper will predominately focus on these additional spacing´s and differences in speed profile.