Aviation & Aeronautics
Intermediate

Specific Range

Distance flown per unit of fuel; maximizing it gives best fuel economy.

Formula

SR=GSf˙SR = \dfrac{GS}{\dot{f}}

Variables

SRSpecific range (nm/lb)
GSGround speed
\dot{f}Fuel flow

Example

Flying at the speed that maximizes specific range gives the most distance per kilogram of fuel.

Did You Know?

Specific range — distance per unit of fuel — is an airliner's equivalent of miles per gallon.

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