French aerospace engineering school the Institut Supérieur de l'Aéronautique et de l'Espace in Toulouse is researching pilot physiological and neurological reactions to stress, with the objective of recognising the signals that precede potential error in order to understand and prevent it.

Backed by the AXA Research Fund, the ISAE is working to understand the patterns of neurological activity that occur when pilots become confused, overloaded, or focused on non-critical inputs to the exclusion of critical ones. This can result in illogical activity, leading to accidents like controlled flight into terrain or loss of control. Examples include the AeroPerú accident of 1996 and the Air France flight 447 disaster of 2009.

Tools used to monitor pilot reactions during flight simulator exercises and real flights include eye-tracking, measurement of pupil dilation, deep brain activity via electro-encephalogram readings and infrared sensors that can show the level of activity in critical surface brain areas. Heart rate also indicates the levels of stress and workload. For example, a take-off in a simulator does not raise the heart rate to the degree it does in a real aircraft.

Prof Frederic Dehais, who holds the AXA chair of neuroergonomics for flight safety at ISAE SUPAERO in Toulouse, says even factors such as "emotional bias" can be recognised. This can be caused, for example, by pilot perception of commercial pressure to land when a go-around would be wiser. Tests on pilots that offered a financial benefit to land versus a small penalty for a go-around show a greater degree of neurological stress, and ISAE hopes to be able to identify the characteristics of differing stresses against a pilot's normative state.

Tests intended to put high workload stress on pilots show progressive neurological reactions, and neurologists can watch as the rational part of the brain deactivates. This is the state in which pilots, for example, ignore loud alert chimes.

This new level of understanding promises to enable manufacturers to eliminate alerts that do not work, and develop completely new systems for attracting the attention of pilots whose cognitive capacity has been swamped: such as a window appearing on the navigation display showing an animation of a pilot carrying out the required action.