Human factors and instructor duty-of-care obligations
This domain tests fitness to fly, fatigue, alcohol and drug limits, and the instructor's duty of care to students.
Impairment and fitness
The Civil Aviation Act sets a blood-alcohol limit for pilots (0.04%) and prohibits acting as pilot while under the influence of alcohol or impairing drugs. A bottle-to-throttle interval applies; the safe rule is no alcohol before flight. Medical certificates, illness, medication and stress all affect fitness. The PIC must not fly if unfit.
Fatigue
Fatigue degrades judgement and reaction time. Flight time limitations and rest requirements apply to operations under Parts 121/125 and to instructors through general duty. An instructor should not conduct training or authorise solo when fatigued, and should monitor student fatigue.
Duty of care
Instructors have supervisory accountability: assess the student's fitness on the day, pressure, stress and confidence; do not authorise solo if the student is unfit or unprepared. Student welfare includes clear briefing, realistic progress expectations and documenting concerns. The instructor's duty is not satisfied by a signature alone.
Worked example
A student has flu, is taking antihistamines and asks to solo. Reasoning: the medication may impair and the student is unwell. The instructor does not authorise solo; the flight is postponed and the student is advised to self-assess and seek medical advice if needed.
Traps
Treating the legal alcohol limit as a safe limit; assuming a current medical means fit today; letting commercial pressure override fatigue; authorising solo without seeing the student.