Instrument Flight Planning and Fuel Management
What this domain tests
Building a fuel plan that satisfies the operating rules, choosing a destination alternate, and understanding how each fuel component is defined.
The fuel breakdown
Every IFR fuel plan has the same building blocks: taxi fuel, trip fuel to the destination, contingency fuel (normally 5% of trip fuel, to cover forecast error), alternate fuel from the missed approach at the destination to the alternate including approach and landing, final reserve (30 minutes holding at 1,500 ft above the aerodrome for turbine aircraft, 45 minutes for piston), and any additional fuel the commander judges necessary. The sum after taxi fuel is the minimum take-off fuel.
Alternates
A destination alternate must normally be filed. It may be omitted only when the destination has an available approach and the forecast, for ETA ±1 hour, gives a ceiling at or above 2,000 ft or the circling minima - whichever is higher - and visibility of at least 5 km.
Worked example
Twin turboprop, 600 lb/hour. Trip 2:00 = 1,200 lb. Contingency 5% = 60 lb. Alternate 20 min = 200 lb. Final reserve 30 min = 300 lb. Taxi 40 lb. Minimum take-off fuel = 1,200 + 60 + 200 + 300 + 40 = 1,800 lb; ramp fuel is 1,800 lb, take-off fuel 1,760 lb. With 2,000 lb usable, only 200 lb is discretionary - about 20 minutes.
Traps
Using a 45-minute final reserve for a turbine aircraft; forgetting that alternate fuel starts at the missed approach point, not at the destination; computing contingency on total fuel instead of trip fuel; planning to minimum fuel and leaving no margin for a holding clearance or a runway change.