Definition
The amount of fuel, in pounds per hour, consumed or required by an engine to produce one unit of power output (one horsepower for piston engines, or one pound of thrust for jet engines) over one hour. Lower values indicate a more fuel-efficient engine.
Plain English
A number that tells you how much fuel an engine burns to produce one unit of power for one hour. The lower the number, the better the engine is at turning fuel into power.
Context Anchor
Seen in engine performance discussions, especially when comparing fuel use, power output, range, or endurance.
Derivation
Called 'specific' (often written this way in technical texts) because the fuel use is measured per unit of power produced, rather than as a total amount. This lets you compare engines of very different sizes on a fair basis.
Why Pilots Care
Lower special fuel consumption means greater range, lower operating costs, and more accurate fuel planning.
Analogy
It is like miles per gallon for a car, but flipped: instead of distance per fuel, it is fuel per unit of power produced. Lower is better.
Intuition Check
Special does not mean a special kind of fuel here. The term is about how much fuel the engine consumes while producing power.
Example Sentence 1
The new engine variant offered a lower specific fuel consumption, giving the aircraft noticeably better range on the same fuel load.
Example Sentence 2
Pilots compare special fuel consumption values when selecting an engine for a long cross-country flight.