Definition
A fuel shutoff valve used in aircraft fuel systems that closes off the flow of fuel by rotating a flat disc, or damper, across the inside of the fuel line. When the valve is operated -- typically by a fire-handle in the cockpit -- the damper swings into position and blocks the passage, stopping fuel from reaching the engine.
Plain English
A valve in the fuel line that uses a hinged flat plate to swing shut and stop fuel flow, usually pulled when there is an engine fire.
Context Anchor
Seen in cabin heat system descriptions, firewall inspections, and emergency discussions about engine-compartment fire or smoke.
Derivation
The word damper comes from the same idea used in a stove or chimney: a flat plate that pivots inside a duct to control or stop flow. Borrowing that name makes the valve's action easy to picture -- a flap that swings across the line to shut it off.
Why Pilots Care
Quickly cutting off fuel prevents an engine fire from growing or spreading into the cabin, directly supporting emergency response and aircraft safety.
Analogy
Think of it like a metal flap door in a duct. When the door is open, air can pass; when it is shut, the path is blocked.
Intuition Check
A damper-type fire valve does not extinguish a fire. Its job is to close an air passage and help isolate the cabin from flames, smoke, or hot gases.
Example Sentence 1
When the pilot pulled the fire handle, the damper-type fire valve rotated shut and cut off fuel to the burning engine.
Example Sentence 2
The mechanic verified that the damper-type fire valve moved freely and sealed properly during the preflight inspection.