Definition
A hand tool used to tighten a threaded fastener (such as a bolt or nut) to a specific, measured amount of rotational force. The wrench indicates the applied torque, usually in inch-pounds, foot-pounds, or Newton-meters, allowing the technician to stop tightening at the exact value specified by the manufacturer.
Plain English
A wrench that measures how hard you are tightening a bolt, so you can tighten it to the exact amount called for and no more.
Context Anchor
Seen in aircraft maintenance manuals and during maintenance tasks where a part must be tightened to a stated value.
Derivation
Torque comes from the Latin torquere, meaning 'to twist.' A torque wrench is literally a tool that measures twisting force, which is exactly what tightening a bolt requires.
Why Pilots Care
Correct torque prevents fasteners from loosening in flight or from being over-tightened and damaged, both of which can lead to component failure.
Analogy
It is like using a measuring cup instead of pouring by guesswork: the goal is not just “enough,” but the exact amount called for.
Intuition Check
A torque wrench is not just a stronger wrench. It is a measuring wrench used to apply a specified amount of twisting force.
Example Sentence 1
The mechanic used a torque wrench to tighten the cylinder hold-down nuts to the value specified in the engine maintenance manual.
Example Sentence 2
During the preflight inspection the technician rechecked the engine mount bolts with a torque wrench.