Effect of wind gradient on the trajectory synthesis algorithms of the Center-TRACON Automation System (CTAS)

Abstract

CTAS consists of three separate tools, and is intended to aid the air traffic controller in efficiently and safely managing the arrival traffic. Integral to the operation of the CTAS is the 4D trajectory synthesis (TS) algorithm that integrates the point mass equations of motion of arriving aircraft to ascertain projected descent trajectories and feeder fix arrival times. Many simplifying assumptions in the equations of motion have been made in the formation of the 4D TS algorithm, including, initially, the omission of the effect of a change in mean wind velocity with altitude, the wind velocity gradient, on the kinematics of the aircraft's descent. Contrary to this assumption, the effect of the wind velocity gradient is shown herein to be significant in the determination of the descent trajectory, and must, therefore, be included in the 4D TS of the CTAS. (Author)