Definition
A fuel system control on aircraft equipped with two main fuel tanks (typically one in each wing) that lets the pilot choose which tank feeds the engine. The selector usually has at least three positions: LEFT (draws fuel from the left tank), RIGHT (draws fuel from the right tank), and OFF (shuts off fuel flow to the engine). Some installations also include a BOTH position.
Plain English
A switch in the cockpit that picks which fuel tank the engine is currently drinking from -- the left wing tank, the right wing tank, or none.
Context Anchor
Seen on airplanes with separate left and right fuel tanks, usually during preflight checks, engine start, and fuel management in flight.
Derivation
Selector comes from a Latin root meaning “to choose.” That fits the aviation use: the control lets the pilot choose one fuel source from the available tanks.
Why Pilots Care
Proper use prevents fuel imbalance, engine starvation, or asymmetric thrust during flight.
Intuition Check
Left/right does not mean which way the handle is moved. It means which fuel tank, left or right, is selected to supply the engine.
Example Sentence 1
After thirty minutes on the left tank, the pilot moved the left/right selector to RIGHT to balance fuel between the wings.
Example Sentence 2
Before engine start, confirm the left/right selector is set to the fuller tank.