The work described here is an attempt to improve an electronic stripping for terminal sectors, VertiDigi, in order to design a version dedicated to the Planning Controller (PC). A brief description of the existing tool is done, as well as its design principles. Past experiments are then evoked. They confirm the good acceptability of the tool for clearance input, but also show the emergence of a specific issue: the Flight Integration Process (FIP). This process includes all the mental, physical and manipulation processes that take place between the announcement of a flight and the actual call from the pilot on the radio frequency. A field observation survey was conducted in summer 2006 in the three Paris Terminal Area centers (Orly, Roissy, and Athis-Mons). The method and tool used to conduct this survey are explained. The data gathered permits a better understanding of this FIP. From there, an iterative design is started, to redesign the tool specifically to meet this FIP issue. The method involves operators as early as possible, and uses paper or low-fidelity mock-ups to capture their needs. The different steps are listed, and the convergence towards a final new design. After a brief description of the new design functionalities, the advantages of this design method are discussed, and future experiments are envisaged to validate the HMI.