Definition
A type of fatigue that develops after prolonged performance of a task, producing measurable degradation in the quality and timing of skilled actions. It typically appears in two ways: a loss of timing and accuracy in coordinated movements, and a narrowing of attention so the pilot fixates on some instruments or tasks while neglecting others.
Plain English
When a pilot has been flying or working at a demanding task for a long time, their hands, timing, and attention start to slip. Movements become less precise, and they begin to focus on a few things while missing others.
Context Anchor
Seen in fatigue and human performance discussions, especially when judging whether a pilot is still fit to fly or should stop and rest.
Derivation
From 'skill' (a learned, practiced ability) and 'fatigue' (from French fatigue, meaning weariness). The pairing highlights that this is not general tiredness but specifically the wearing down of practiced abilities — the very things a pilot relies on most.
Why Pilots Care
It increases the chance of procedural errors, altitude deviations, and delayed decisions during critical phases of flight.
Analogy
Like a skilled driver who begins to drift out of lane or miss gear changes after many hours on the road without feeling sleepy.
Grounding Statement
Skill fatigue is when tiredness starts showing up in the quality of your flying, even though you still know what you are trying to do.
Intuition Check
Skill fatigue does not mean the pilot lacks skill. It means tiredness is temporarily reducing the pilot’s ability to use that skill well.
Example Sentence 1
After four hours of hand-flying in turbulence, the instructor recognized the signs of skill fatigue and took a short break before continuing the lesson.
Example Sentence 2
The instructor recognized skill fatigue when the student began to omit checklist items that had been performed correctly earlier in the lesson.