Flight planning and fuel management
Flight planning and fuel management
This domain tests whether you can build a defensible fuel plan and decide when an alternate or holding fuel is required. CAA NZ expects numbers you can justify, not a single total.
Fuel components. Plan taxi/start, trip fuel (using forecast winds and actual cruise flow), contingency (ICAO 5% of trip fuel for international IFR), alternate fuel, final reserve and any extra. Under NZ CAR Part 91, VFR fuel must reach the destination with 30 minutes (day) or 45 minutes (night) at normal cruise; IFR planning adds alternate fuel where an alternate is required plus a 45-minute reserve. Reserve fuel is calculated at the flow you would actually use - normally cruise flow, not climb flow.
Planning minima. If the destination forecast is below the planning minima, or the only suitable weather is at an alternate, the alternate must be carried in the plan. Use TAF and trend, not a single METAR.
Worked example. Leg 120 NM, TAS 110 kt, forecast wind gives GS 100 kt. Taxi/run-up 10 L, cruise flow 36 L/h, day VFR. Trip time = 120/100 = 1.2 h = 72 min. Trip fuel = 36 × 1.2 = 43.2 L. Reserve = 36 × 0.5 = 18 L. Total = 10 + 43.2 + 18 = 71.2 L, rounded to 72 L. On a 100 L uplift, landing fuel is 28 L.
Traps. Using TAS instead of GS for time and fuel; applying the reserve at holding flow; mixing litres, US gallons and kilograms (avgas ≈ 0.72 kg/L); forgetting the go-around or taxi-in; and accepting a tailwind forecast beyond its validity period.