The fuel fraction for warm-up, taxiing, and take-off, often referred to as “WTT” (Warm-up, Taxi, and Take-off) fuel fraction, is a parameter used in aircraft design and performance analysis. It represents the proportion of an aircraft’s total fuel consumption that is typically consumed during the warm-up, taxiing, and take-off phases of a flight. This fraction is used to estimate the fuel required for these initial phases before the aircraft reaches cruising altitude.
The formula for calculating the WTT fuel fraction is as follows:
- Fuel Burned during Warm-up, Taxi, and Take-off” is the amount of fuel consumed during these initial flight phases (typically in kilograms or pounds).
- “Total Fuel Onboard” is the total amount of fuel carried by the aircraft at the start of the flight (typically in kilograms or pounds).