Flight Performance and Planning
Performance fundamentals
Candidates must understand take-off and landing performance: the balanced field length, the decision speed V1, Vr and V2, and the effect of mass, density altitude, wind, runway slope and contamination. Learn the climb segments (take-off, en-route, approach) and the gradients required, and the difference between gross and net performance. For planning, know fuel policy (taxi, trip, contingency, alternate, final reserve), the load sheet and its CG implications, and the effect of CG position on performance and handling. Mass and balance calculations must be practised until the arithmetic is automatic.
Traps in questions
A common trap is forgetting that density altitude rises with temperature and pressure altitude, so take-off distance increases even when the mass is unchanged. Another is confusing V1 with Vr, or assuming a headwind always improves the climb gradient. Questions also test the difference between the maximum structural mass and the performance-limited mass, and whether a runway is limiting on take-off or landing.
Worked example
"Runway 2,000 m, elevation 500 ft, OAT 30 °C, mass near MTOM. Is the take-off limiting?" Answer: compute density altitude, apply the aircraft's performance chart, and compare the required distance with the available distance. Rule of thumb: hot, high and heavy all push the same way.
Key points
- Density altitude rises with temperature and pressure altitude.
- Know V1, Vr and V2 and their roles.
- Fuel policy: taxi, trip, contingency, alternate and final reserve.
- CG position affects both performance and handling.
- Distinguish structural from performance-limited mass.