CTO Fatigue Management & Human Factors 5 — Questions and Answers
Question 1: Which error-producing condition in the HFACS framework directly relates to fatigue management failures?
- Adverse mental states (physiological state) (Correct answer)
- Routine violations at the organizational level
- Supervisory planned inappropriate operations
- Perceptual errors from environmental factors
Correct answer: Adverse mental states (physiological state)
HFACS places fatigue under 'adverse mental states' within the Unsafe Acts layer, caused by pre-conditions including inadequate rest.
Question 2: Which physiological sign is the EARLIEST reliable indicator of cumulative fatigue in a controller during a shift?
- Increased frequency of attention lapses and task-switching errors (Correct answer)
- Slurred speech on radio communications
- Visible nodding off at the position
- Complaints of headache and blurred vision
Correct answer: Increased frequency of attention lapses and task-switching errors
Attention lapses and subtle task-switching errors emerge early in cumulative fatigue before more obvious physical symptoms appear.
Question 3: An air traffic facility implements mandatory 30-minute breaks every 2 hours during overnight shifts. This policy is PRIMARILY intended to:
- Interrupt monotony and allow brief sleep recovery to sustain alertness (Correct answer)
- Meet FAA staffing ratio requirements for peak traffic periods
- Give supervisors time to complete administrative tasks
- Reduce radio frequency congestion during quiet periods
Correct answer: Interrupt monotony and allow brief sleep recovery to sustain alertness
Scheduled breaks during overnight shifts combat the circadian nadir by allowing short recovery rest and reducing the monotony that accelerates fatigue.
Question 4: The 'Swiss Cheese model' of accident causation is most applicable to ATC fatigue incidents because it shows:
- Multiple defensive layers must all fail simultaneously for an accident to occur (Correct answer)
- A single fatigue event inevitably causes a critical safety failure
- Fatigue management is the sole barrier to ATC accidents
- Individual controllers bear sole responsibility for error prevention
Correct answer: Multiple defensive layers must all fail simultaneously for an accident to occur
The Swiss Cheese model illustrates that accidents result from aligned holes in multiple defensive layers, showing the importance of redundant safeguards beyond individual controller vigilance.
Question 5: A controller transfers to a facility 3 time zones westward. To minimize circadian disruption, the controller should:
- Gradually shift sleep time earlier by 1–2 hours per day before the move (Correct answer)
- Force immediate adaptation by staying awake for 24 hours on arrival
- Take melatonin in the morning to advance the sleep phase rapidly
- Request permanent night shifts at the new facility to avoid adjustment
Correct answer: Gradually shift sleep time earlier by 1–2 hours per day before the move
Gradually advancing sleep timing before westward travel helps pre-adapt the circadian clock, reducing disruption compared to abrupt schedule changes.
Question 6: Which type of memory is MOST vulnerable to fatigue-related degradation during ATC operations?
- Working memory (short-term retention of multiple flight data elements) (Correct answer)
- Long-term procedural memory for standard phraseology
- Semantic memory for ATC regulations
- Episodic memory for past operational incidents
Correct answer: Working memory (short-term retention of multiple flight data elements)
Working memory, which holds multiple active data points like callsigns, altitudes, and headings simultaneously, degrades rapidly under fatigue.
Question 7: Under 14 CFR Part 65, a controller who is taking a sedating antihistamine for allergies is required to:
- Refrain from performing ATC duties until the medication is no longer affecting performance (Correct answer)
- Report the medication to the facility medical officer only if symptoms worsen
- Continue working but limit duties to ground control only
- Obtain a special medical waiver from the FAA within 48 hours
Correct answer: Refrain from performing ATC duties until the medication is no longer affecting performance
Regulations require controllers not to exercise privileges of their certificate while impaired by any medication that affects their faculties, including sedating antihistamines.
CTO Fatigue Management & Human Factors 5
Which error-producing condition in the HFACS framework directly relates to fatigue management failures?