Flight Planning and Meteorology
Planning a flight
Know the sequence: route selection, weather briefing, fuel calculation (taxi, trip, reserve, contingency), weight and balance, performance (take-off/landing distances, climb gradients), and alternates. Understand MTOW, MLW, ZFW and how payload and fuel trade off. Fuel reserves in Australia typically include a fixed reserve plus variable reserve; always check the current regulation rather than assuming.
Weather knowledge
Learn the ISA, lapse rates, pressure systems, fronts, and cloud families. Understand stability: unstable air gives cumuliform cloud and showers, stable air gives stratiform cloud and steady rain. Know how temperature/dewpoint spread predicts fog and cloud base, and how mountain waves, sea breezes and thunderstorms form. Decode METAR and TAF, and know the meaning of QNH, QFE and QNE.
Traps in questions
- Confusing QNH (altitude above mean sea level) with QFE (height above aerodrome).
- Forgetting that a low QNH means the aircraft is lower than the altimeter suggests.
- Using surface wind instead of forecast winds aloft for cruise fuel planning.
- Treating TAF as an observation rather than a forecast.
Worked example: cloud base estimate
Surface temperature 24 °C, dewpoint 18 °C, spread 6 °C. Rule of thumb: cloud base ≈ spread × 400 ft = 2,400 ft AGL. This quick estimate helps assess VFR minimums; confirm against the actual TAF and METAR before flight.