Fatigue and coastal fog before a VFR departure
You are a PPL holder at Swakopmund. You have completed three scenic flights since 07:00, logged 5.5 hours, and are now at 18:00 with 9 hours on duty. You slept about two hours because of noise at the lodge, drank little water, and skipped lunch. You plan a VFR flight to Windhoek in a C172 with two passengers. The coastal forecast gives fog and low stratus moving inland, cloud base 600 ft, visibility 3 km, and the route climbs over terrain rising to 7,000 ft. The aircraft is serviceable and fuelled for 3.5 hours; the flight should take 2.0 hours. You feel 'a bit tired' but eager to get home. A colleague says the fog usually stays at the coast on this route.
1. Assess the pilot's fitness to fly using IMSAFE and fatigue risk.
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Fatigue is the dominant red flag. Two hours of sleep, 9 hours on duty, 5.5 hours of flying, dehydration and a skipped meal produce cumulative fatigue, not just mild tiredness. Using IMSAFE: Illness none reported; Medication none reported; Stress includes eagerness to get home and passenger pressure; Alcohol none reported; Fatigue is clearly present; Eating is inadequate. Fatigue degrades judgement, risk perception, scan, reaction time and the ability to resist an optimistic colleague's comment. The pilot is likely to accept a marginal weather picture because the goal is to get home. The correct assessment is 'not fit to fly' until rested, hydrated and fed. A short nap and a meal may help, but the duty and sleep history still point to delaying until the next morning.
2. Interpret the weather threat and decide whether to depart.
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Fog and low stratus with a 600 ft cloud base, 3 km visibility and terrain rising to 7,000 ft make this a high-risk VFR flight. If the cloud moves inland, the route becomes instrument meteorological conditions over rising ground, with a serious controlled-flight-into-terrain risk. The pilot has no instrument rating and the aircraft is not equipped for IMC. The colleague's statement that the fog 'usually stays at the coast' is anecdotal, not a forecast. The safe decision is not to depart: overnight, delay until morning when the fog clears, or use surface transport. If the passengers pressure the pilot, explain the terrain and visibility risk. Do not launch to 'have a look'.
3. If you had already departed and the fog closed the route ahead, what actions would you take?
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Make an immediate 180-degree turn back to the coast or to the last known VMC area. Do not scud-run below the cloud or climb blindly into it. Use GPS and the chart to navigate to Walvis Bay or Swakopmund, and land at the nearest suitable aerodrome before the fog reaches it. If the aircraft inadvertently enters cloud, maintain control on instruments, avoid descending until terrain clearance is known, and turn back. Declare an emergency on 121.5 if trapped and request help. The priority is to stay in VMC and land, not to complete the planned flight. Passenger pressure is irrelevant once the weather has closed in.