Flight Planning and Instrument Flight Procedures
Flight Planning and Instrument Flight Procedures
This domain asks you to build a legal, flyable IFR profile: fuel, route altitudes, alternates, terminal procedures, holding and descent planning. Questions are typically numerical - fuel figures, gradients, distances and timings - so show the arithmetic.
Fuel and reserves (ICAO-style scheme)
- Taxi fuel, trip fuel, contingency fuel (commonly 5% of trip fuel, or 3% with an en-route alternate), alternate fuel, final reserve (30 minutes holding at 1,500 ft above the destination in ISA for turbine aeroplanes; 45 minutes for piston), plus additional fuel for the missed approach, forecast icing or an isolated destination.
- Contingency is a percentage of trip fuel, not of total fuel on board.
Route altitudes
- MEA guarantees obstacle clearance and navaid reception; MOCA guarantees obstacle clearance only, so reception may fail between fixes.
- MORA gives 1,000 ft clearance (2,000 ft where terrain reaches 5,000 ft) within 10 NM of the route.
Holding
Standard pattern is right turns, 1-minute inbound legs at and below 14,000 ft and 1.5 minutes above, with the outbound leg adjusted for wind so the inbound timing is correct.
Worked example
Descending from FL 350 to 3,000 ft: 32,000 ft to lose. A 3° gradient is about 318 ft/NM, so 32,000 ÷ 318 ≈ 101 NM, plus roughly 10 NM for deceleration and configuration - start down about 110 NM out. At 450 kt ground speed the descent takes about 15 minutes, an average of roughly 2,100 ft/min.
Traps
- Omitting the missed approach from fuel planning.
- Using MOCA where navaid reception matters for the next leg.
- Forgetting the 1.5-minute holding legs above 14,000 ft.