Thrust-specific fuel consumption: Difference between revisions

There also exists power specific fuel consumption, which equals speed times the thrust specific fuel consumption. It can have units of pounds per hour per horsepower.
(Made headers in table less ambiguous. Added an explanation of the last table.)
(There also exists power specific fuel consumption, which equals speed times the thrust specific fuel consumption. It can have units of pounds per hour per horsepower.)
TSFC or SFC for [[reaction engine|thrust engine]]s (e.g. [[turbojet]]s, [[turbofan]]s, [[ramjet]]s, [[rocket engine]]s, etc.) is the mass of [[fuel]] needed to provide the net thrust for a given period e.g. lb/(h·lbf) (pounds of fuel per hour-pound of thrust) or g/(s·kN) (grams of fuel per second-kilonewton). Mass of fuel is used rather than volume (gallons or litres) for the fuel measure since it is independent of temperature.<ref>[http://selair.selkirk.bc.ca/Training/Aerodynamics/range_prop.htm Specific Fuel Consumption<!-- Bot generated title -->]</ref>
 
Specific fuel consumption of air-breathing jet engines at their maximum efficiency is more or less proportional to speed. The fuel consumption ''per mile'' or ''per kilometre'' is a more appropriate comparison for aircraft that travel at very different speeds. There also exists [[power specific fuel consumption]], which equals speed times the thrust specific fuel consumption. It can have units of pounds per hour per horsepower.
 
This figure is inversely proportional to [[specific impulse]].