Flight Performance and Planning
Flight Performance and Planning tests mass and balance, takeoff and landing performance, and the fuel and altimetry planning needed for a safe flight.
Mass and balance
- Limits: MTOM, MLM, MZFW and maximum floor load; CG must remain within forward and aft limits for all phases.
- Moment = mass × arm. Total mass and total moment give CG. %MAC = (CG - LEMAC)/MAC × 100.
- Forward CG: higher stall speed, longer takeoff, heavier stick forces; aft CG: lower stability and possible pitch-up.
Performance
- Takeoff: TORA, TODA, ASDA, clearway and stopway. Screen height is 35 ft for transport-category takeoff and 50 ft for landing.
- Factors: mass, altitude, temperature, wind, slope, runway condition and contamination. Use approved charts, not mental estimates.
Flight planning and monitoring
- Fuel: taxi, trip, contingency, alternate, final reserve and extra. Monitor against plan at waypoints and recalculate.
- Altimetry: QNH for elevation, QFE for height above aerodrome, standard 1013.25 hPa above transition altitude.
Worked example
Basic empty mass 1,500 kg at 2.40 m; pilot 80 kg at 1.80 m; front passenger 80 kg at 1.80 m; two rear passengers 160 kg at 3.20 m; fuel 300 kg at 2.60 m. Moments: 3,600 + 144 + 144 + 512 + 780 = 5,180 kg·m. Total mass 2,120 kg. CG = 5,180/2,120 = 2.44 m. If the aft limit is 2.42 m, the loading is out of limits and must be adjusted.
Traps
- Forgetting zero-fuel mass.
- Using fuel volume as mass.
- Ignoring wind, slope and contaminated-runway corrections.