Definition
A measure of a jet engine's fuel efficiency, expressed as the weight of fuel burned per hour for each pound of thrust produced. Lower TSFC values indicate a more fuel-efficient engine.
Plain English
How much fuel a jet engine burns each hour to produce one pound of thrust. The smaller the number, the better the fuel economy.
Context Anchor
Seen in turbine engine performance data, engine comparisons, and powerplant maintenance discussions.
Derivation
Built from three plain words: 'thrust' (the pushing force the engine produces), 'specific' (meaning 'per unit of' — in this case, per pound of thrust), and 'fuel consumption' (how much fuel is burned). Put together: fuel burned per unit of thrust.
Why Pilots Care
A lower value means the engine delivers more thrust for less fuel, directly affecting aircraft range, operating costs, and payload capacity.
Analogy
TSFC is like a fuel-mileage number for a thrust-producing engine, but flipped around: instead of miles per gallon, it is fuel used for each unit of push. Lower is better.
Intuition Check
Do not read “specific” as “exact” or “detailed” here. In TSFC, “specific” means fuel use measured per unit of thrust.
Example Sentence 1
The newer turbofan had a lower TSFC than the older engine, giving the aircraft better range on the same fuel load.
Example Sentence 2
Comparing TSFC values helped the team decide which engine variant offered the best fuel economy for the mission profile.