In this paper an algorithm for formation of a set of conflict-free trajectories from current airplane position to the predetermined trajectory change point (TCP) to resolve traffic and terrain conflicts is proposed. Algorithm provides TCP arrival time synchronization with an airplane ahead and safe altitude clearance above terrain. An algorithm for calculation of velocity along those trajectories is described. This algorithm generates 4D trajectories that meet specified standards of longitudinal separation at the TCP. This technique can be implemented in on-board integrated surveillance system (ISS) to provide pilots with alerts and recommendations to prevent dangerous evolution of flight situation and increase flight safety.