Definition
Cockpit gauges that display the pressure and the rate of fuel being delivered to the engine in a fuel-injected aircraft. The pressure indicator shows the pressure of fuel in the system, and the flow indicator shows how much fuel is being metered to the cylinders, typically in gallons or pounds per hour.
Plain English
Two gauges in the cockpit that tell the pilot how hard the fuel is being pushed and how much is actually getting to the engine right now.
Context Anchor
Seen on the engine instrument panel, especially during engine start, run-up, takeoff, climb, and any time engine performance seems abnormal.
Derivation
“Indicator” comes from a Latin word meaning “to point out” or “show.” That fits the aviation use: these instruments point out the condition of fuel delivery rather than controlling the fuel themselves.
Why Pilots Care
They allow pilots to verify that the fuel system is operating correctly and to detect problems such as blockages or pump failures before they lead to engine issues.
Intuition Check
Do not confuse fuel pressure/flow indicators with fuel quantity gauges. These indicators show fuel being delivered to the engine; they do not directly tell you how much fuel remains in the tanks.
Example Sentence 1
After advancing the throttle for takeoff, she scanned the fuel pressure and flow indicators to confirm both were in the green arc.
Example Sentence 2
A sudden drop on the fuel pressure/flow indicators alerted the pilot to a potential issue in the fuel injection system.