Definition
A twisting or rotational force. In a single-engine propeller airplane, torque refers to the reaction force from the spinning propeller and engine that tends to roll the airplane in the opposite direction of propeller rotation. For most U.S.-built engines, the propeller turns clockwise as seen from the cockpit, so the torque reaction tends to roll the airplane to the left, especially at high power and low airspeed (such as during takeoff and climb).
Plain English
A turning force. When the propeller spins one way, the airplane wants to roll the other way. On most trainers, that means a left-rolling tendency when you apply lots of power, like during takeoff and climb.
Context Anchor
Seen in takeoff and climb discussions, especially when the engine is producing high power and the airplane is moving relatively slowly.
Derivation
From the Latin 'torquere,' meaning 'to twist.' Same root as 'torque wrench' (a tool that measures twisting force) and 'distort.' This helps because torque is literally a twisting force — not a push or a pull, but a rotation around an axis.
Why Pilots Care
Pilots must apply opposite rudder to maintain coordinated flight, especially during high-power, low-speed phases like takeoff and initial climb.
Analogy
Torque is like the twist you feel when using a wrench. You are not just pushing the wrench; you are applying a turning force around the bolt.
Intuition Check
Torque does not mean engine power in general. Here, it means the twisting effect produced when the engine turns the propeller.
Example Sentence 1
On the takeoff roll, the student added right rudder to counter torque and keep the airplane on the centerline.
Example Sentence 2
At higher speeds during the climb, the pilot needed less right rudder because the torque effect became weaker.