Night Navigation
Planning a night navigation leg
Night navigation uses the same dead reckoning as day, but with fewer outside cues. Before flight, calculate heading, groundspeed, ETA and fuel for each leg, and note minimum safe altitude, terrain, obstacles, airspace and the lighting hours or PPR of destination and alternate. Carry a log with time marks and a planned position report at each turning point.
In flight
Maintain a steady heading and altitude, and update ETA at each fix. Use VOR, DME, NDB or GNSS to confirm position rather than waiting for a town to appear. Lit roads, towns and airfields are useful but can be misidentified; cross-check with a bearing or distance. Keep a listening watch and make position reports as required. The autopilot reduces workload but must be monitored, especially during heading or altitude captures.
Worked example
Leg length 45 nm, true airspeed 110 kt, no wind: ETA 24.5 min. After 11 minutes you fix 2 nm left of track. Reasoning: 2 nm in about 18 nm flown is roughly 6° track error; turn 12° right to converge, then 6° right to hold track. The 18 nm in 11 min gives a ground speed of about 98 kt, so the revised ETA is about 27.5 min from start.
Traps
Over-reliance on GPS without a chart cross-check; failing to revise ETA and fuel; map reading under red light and missing symbols; and drifting off track while distracted by cockpit lighting.