In their efforts to break with aircraft assistance, Thales Avionics and the ENSC (Ecole Nationale Supérieure de Cognitique) - through the work carried out within their Human Factors for Aerospace Laboratory (HEAL) - have been investigating HMIs assisting pilots in the anticipation process. The approach is user-centred: the understanding of the cognitive mechanisms underlying the anticipation process allows a context-dependent anticipation model to be devised, which aims at designing an ecological assistance tool for pilots. A possible approach to the anticipation process consists of investigating how cognitive plans are developed. To start with, the concepts of anticipation and planning are reviewed. By comparing their definitions, both concepts can be clearly differentiated and the essential function of a plan can be emphasised. The question of the plan as a means of saving cognitive resources is then addressed. Examples in aeronautics are given. Several relevant surrounding psychological concepts are introduced, pointing out the main features of the plan: hierarchy and deficiency. To conclude, based on the conditions of implementation of the plan, the mechanisms of anticipation are discussed, which are close to the principle of reafference.
