Commercial Pre-Flight Fuel Planning

Alternate Selection Requirements

• Standard: At least one destination alternate must be selected.
• Two Alternates: Required if:
  • Weather at destination is marginal ($< 2,000$ ft ceiling or $< 3$ miles visibility) for 1 hr before/after ETA.
  • No meteorological information is available for destination.

Special Fuel Procedures

Isolated Aerodrome Procedure

If no suitable alternate exists (e.g., island destination):

• Carry fuel to fly to destination.
• Additional fuel to fly for 2 hours at normal cruise consumption (final reserve included).

Predetermined Point (PDP) Procedure

Used when the destination alternate is not available or reliable. The flight plan includes a PDP where a decision is made to either:

1. Continue to destination and land with mandatory reserves.
2. Divert to an en-route alternate.

Reduced Contingency Fuel (RCF)

Allows carrying less than 5% contingency fuel by using a Decision Point en-route.

• At the Decision Point, the pilot checks fuel.
• If fuel $\ge$ Required Fuel to Destination + Reserves, continue.
• If fuel $<$ Required, divert to a closer alternate (commercial stop).
• Typically reduces contingency to 3% or 5 minutes (whichever is greater).

Factors Calculating Fuel

Fuel planning must take into account:

• Expected taxi time.
• Expected departure/arrival routes (SIDs/STARs).
• Forecast meteorological conditions (wind/temp).
• Mass of the aeroplane.
• Performance data (fuel flow charts).