Forgetting, or the unconscious interruption of a conscious mental process

Follow-up to the article "In microlight maintenance, error is not inevitable" by Bernard Boudou (ULM Info 120)

In aviation, an omission, a lapse or a diversion of attention by someone involved is sometimes the root cause of an accident or an unusual situation.

Training in certain piloting actions makes it possible to move from a conscious, deliberate mode in the novice to an automatic mode as the person progresses. They can then handle information from several senses without particular effort. The pilot of a three-axis microlight can, for example, watch the attitude while controlling stick force and listening to radio communications (actions Α, Β and Γ in figure A). As experience builds, the pilot becomes free to carry out a new activity that demands mental capacity, such as switching fuel tanks (action Δ). What happens if, at that moment, something else demands their attention, such as a question from an air traffic controller (question ε)?

The brain can only handle one conscious, deliberate operation at any given moment. It must first interpret the additional element, then choose which treatment takes priority, and finally inhibit one operation in order to carry out the other. This inhibition mechanism uses energy to filter out irrelevant information and keep only what is needed for the chosen operation. Once the latter is finished (action Ε in figure A), how can you be sure to return to the previous one (information δ, action Δ)? This arises whenever the pilot feels saturated or distracted. To cope with such situations, several techniques are taught, even though in practice none is infallible. This subject is covered in detail in many books on human factors.

In the 1990s, Transport Canada published “The Dirty Dozen”, a series of posters illustrating twelve of the most common work situations that can lead to an accident. One of these posters was entitled “Distraction”. We reproduce it here. https://tc.canada.ca/en/aviation/general-operating-flight-rules/aviation-safety-poster-gallery

Bernard BOUDOU