Fatigue and Spatial Disorientation on Night ILS
You are a single pilot flying a Cessna 172S on an IFR night approach into Ben Gurion (LLBG), runway 26, after a 14-hour duty day that included six VFR legs and 9 h flight time. The weather is 600 ft ceiling, 2 km visibility, wind 270/15G25. You are cleared for the ILS, 4 nm final, and have just completed two missed approaches. You feel unusually tired, have a mild headache, and notice you are staring at the glideslope needle. On short final, you feel a sudden sensation of turning and the runway lights appear to move. The autopilot is off. You have 1 h 30 min of fuel and the alternate is 20 min away with better weather. The aircraft is serviceable.
1. What human factors are present and how do they affect your performance?
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Fatigue is significant after 14 hours of duty and 9 hours of flight, and it reduces attention, reaction time, and instrument scan discipline. The mild headache may indicate dehydration or early hypoxia, although at low altitude hypoxia is less likely; either way it degrades performance. Fixation on the glideslope needle shows attention narrowing, so the localizer and airspeed may be neglected. The sensation of turning and moving runway lights in low visibility at night is consistent with spatial disorientation, where visual illusions conflict with instrument indications. Two missed approaches already increase stress and fatigue. The combination is dangerous because the pilot may trust the illusion rather than the instruments, or may press on to avoid another go-around.
2. What immediate action should you take and why?
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Go around immediately. Apply takeoff/go-around power, establish a positive climb on the attitude indicator, and fly the published missed approach using instruments. Do not chase the illusion or stare at the runway lights. Engage the autopilot if it is serviceable and approved for the phase of flight, or use the flight director to reduce workload. Declare the go-around and your fatigue to ATC, and request vectors for a diversion to the alternate. The reason is that an unstable or disorientated approach at 600 ft ceiling and 2 km visibility leaves no margin for a late correction; going around converts an ambiguous situation into a controlled climb.
3. How should you manage the rest of the flight and what would you report?
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Do not attempt a third approach at LLBG. Divert to the alternate with better weather, using the autopilot and a simple instrument scan. Tell ATC: 'Cessna 172, going around, pilot fatigue, request diversion to the alternate.' After landing, complete a fatigue report and do not continue duty without rest. The key judgement is that the problem is not just the approach; it is the pilot's degraded state. A safe diversion and rest is the correct outcome, even though it delays the flight. Continuing to shoot approaches to 'get in' would be a classic fatigue-driven decision error.