Towards a model for the study of written procedure following in dynamic environments

Flight safety relies on a large number of automatisms and on strict written procedure following. This article presents a psycho-cognitive analysis of the procedure following task. Consequently, we have proposed a model called SPEED (Suivi de Procédures Ecrites dans les Environnements Dynamiques: Written Procedure Following in Dynamic Environments). SPEED enables the understanding of the use of written procedure in dynamic environments. It describes the reasons why pilots do not follow procedures as the manufacturers and airlines require. SPEED breaks down the activities involved in the use of procedures into nine stages: (1) detecting triggering conditions, (2) elaborating a diagnosis, (3) determining whether a procedure is needed, (4) accessing and searching for the appropriate written procedure, (5) reading and understanding the items of the procedure, (6) assessing the relevance of the procedure, (7) planning actions, (8) executing the planned actions and (9) evaluating the outcome of actions. SPEED is not as a sequential model. It is an iterative model, where some steps may be optional.