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Endurance
Endurance is the amount of fuel available on board expressed in time. With a known amount of fuel on board we can find the endurance by first looking up the fuel consumption in the given tables.
Amount of fuel : fuel consumption = endurance
Required amount of fuel
When the power setting and flight time is given, we can calculate the required amount of fuel by first looking up the fuel consumption for that power setting in the tables and then multiplying that with the flight time.
Fuel consumption x flight time = fuel required
Safe endurance
Another way to determine the endurance is with the dedicated graph in the flight manual. However, this will only deliver values for full tanks so it is not possible to simply calculate the values for our actual fuel load (other than full) because the graph includes the fuel required for start-up, taxi and climb, as wel as a 45min reserve at power setting of 45%. (this all will be stated in a note on the graph).
These values cannot simply be taken out of the calculation. The endurance taken from these graphs are referred to as the "safe endurance".
Range
The range of an aircraft is the distance it can travel with a specified amount of fuel on board.
Range (NAM) = endurance x TAS
(because TAS, and not GS is used here, the range will be in Nautical Air Miles. To find the distance relative to the ground, calculate GS from the TAS and wind component).
TAS + Tailwind = GS
TAS - Headwind = GS
Specific Air Range
SAR = TAS / Fuel Flow
Endurance is the amount of fuel available on board expressed in time. With a known amount of fuel on board we can find the endurance by first looking up the fuel consumption in the given tables.
Amount of fuel : fuel consumption = endurance
Required amount of fuel
When the power setting and flight time is given, we can calculate the required amount of fuel by first looking up the fuel consumption for that power setting in the tables and then multiplying that with the flight time.
Fuel consumption x flight time = fuel required
Safe endurance
Another way to determine the endurance is with the dedicated graph in the flight manual. However, this will only deliver values for full tanks so it is not possible to simply calculate the values for our actual fuel load (other than full) because the graph includes the fuel required for start-up, taxi and climb, as wel as a 45min reserve at power setting of 45%. (this all will be stated in a note on the graph).
These values cannot simply be taken out of the calculation. The endurance taken from these graphs are referred to as the "safe endurance".
Range
The range of an aircraft is the distance it can travel with a specified amount of fuel on board.
Range (NAM) = endurance x TAS
(because TAS, and not GS is used here, the range will be in Nautical Air Miles. To find the distance relative to the ground, calculate GS from the TAS and wind component).
TAS + Tailwind = GS
TAS - Headwind = GS
Specific Air Range
SAR = TAS / Fuel Flow
