Definition
A small metal vane mounted in the exhaust stream of a turboprop or turbojet engine that deflects exhaust gases to produce reverse thrust when the propeller or thrust reverser system is moved into the reverse position.
Plain English
A flat metal piece placed in the engine's exhaust that redirects the hot gases forward so the engine pushes the aircraft backward instead of forward.
Context Anchor
Seen in aircraft maintenance, especially during propeller or helicopter rotor vibration checks, tracking checks, and balancing work.
Derivation
The word 'target' here is used in the sense of 'something an object is aimed at or strikes.' The blade is the surface the exhaust gases strike, which then deflects them. This use of 'target' parallels its use in 'target reverser' on jet engines.
Why Pilots Care
Reverse thrust shortens landing rollout and helps slow the aircraft on contaminated runways. Knowing how it is generated helps the pilot understand why reverse is only available with the engine running and producing exhaust flow.
Intuition Check
Do not read target blade as a blade being struck or damaged. In this context, target means the selected reference blade used for comparison.
Example Sentence 1
When the pilot selected reverse, the target blades swung into the exhaust stream and deflected the gases forward to slow the aircraft.
Example Sentence 2
After the adjustment, every blade passed within limits of the target blade during the tracking run.