Definition
A cockpit instrument that displays the rate at which fuel is being delivered to the engine, typically shown in pounds per hour (PPH) or gallons per hour (GPH). In turbine-powered aircraft, it indicates fuel flow to the combustion section; in piston aircraft, it indicates fuel flow to the fuel injection system or carburetor.
Plain English
A gauge that tells the pilot how much fuel the engine is using right now, measured per hour.
Context Anchor
Seen on the engine instruments during engine start, takeoff, climb, cruise, and troubleshooting.
Why Pilots Care
It lets the pilot verify proper fuel delivery, monitor fuel efficiency, and detect problems such as blockages or pump failures before they affect engine performance.
Analogy
Like a speedometer that tells you how fast fuel is flowing into the engine instead of how fast the airplane is moving.
Intuition Check
Do not confuse fuel flow with fuel quantity. Fuel quantity tells how much fuel is in the tanks; fuel flow tells how fast fuel is being used.
Example Sentence 1
After setting cruise power, the pilot leaned the mixture and watched the fuel flow indicator drop to the value listed in the performance chart.
Example Sentence 2
In cruise the fuel flow indicator read 12 gallons per hour, matching the performance chart for the power setting.