Definition
A physical arresting system installed at or near the end of a runway, designed to safely stop a jet aircraft that has overrun or aborted takeoff. Typically consists of a net, cable, or webbing barrier that engages the aircraft and absorbs its energy through anchored brakes or tape reels. Shown as a symbol on FAA airport diagrams to mark its location.
Plain English
A safety net or cable system at the end of a runway that catches a jet if it can't stop in time.
Context Anchor
Seen on airport sketches and airport diagrams as a marked runway feature, usually near the end of a runway.
Derivation
"Barrier" comes from Old French barriere, meaning a fence or obstacle to block passage. Here it's a deliberate obstacle placed to safely stop a jet that would otherwise run off the runway.
Why Pilots Care
Prevents injury to people and damage to vehicles or buildings from jet blast during taxi, takeoff, or engine run-ups.
Intuition Check
Do not assume a jet barrier is a wall that blocks jet blast or protects people from engine exhaust. In this airport-diagram context, it means emergency stopping equipment for certain aircraft.
Example Sentence 1
The airport diagram showed a jet barrier at the departure end of Runway 27.
Example Sentence 2
Ground crews waited behind the jet barrier while the airliner completed its engine start sequence.