Plain English Meaning

A long screw that, when turned, slowly pushes or pulls something heavy in a straight line. Spinning the screw moves the attached part forward or back in a controlled way.

Full Definition

A mechanical device consisting of a threaded shaft (the screw) turning inside a matching threaded sleeve (the nut), used to convert rotary motion into precise linear motion for moving, positioning, or lifting heavy aircraft components. Jackscrews are commonly used to drive trim surfaces such as the horizontal stabilizer, to extend and retract certain landing gear, and to operate flight control surfaces or doors.

Context Anchor

Seen in aircraft maintenance when inspecting trim systems, flap mechanisms, actuators, and screw- lifting or positioning devices.