Definition
A type of stranded steel control cable in which each individual wire is shaped into the helical form it will take in the finished cable before the strands are laid up together. Because the wires are pre-shaped, the cable lies flat when cut, resists unraveling, and distributes loads evenly between strands.
Plain English
A flight-control cable whose tiny wires have been bent into their final spiral shape before being twisted together. This makes the cable hold its shape, lie flat when cut, and not spring apart at the ends.
Context Anchor
Seen in aircraft maintenance manuals, control-cable replacement instructions, and inspection discussions for flight control systems.
Derivation
‘Preformed’ comes from Latin prae- (‘before’) and formare (‘to shape’) — literally ‘shaped beforehand.’ The name describes the manufacturing step: each wire is formed into its spiral shape before assembly, rather than being forced into shape by the twisting process.
Why Pilots Care
Reduces the risk of control binding, uneven tension, and early fatigue failure in primary flight controls.
Intuition Check
Preformed cable does not mean a cable assembly that is already cut to length with ends installed. It means the individual wires were shaped ahead of time to fit the cable’s final spiral form.
Example Sentence 1
The aileron control runs use preformed cable so the strands stay seated and the ends do not unravel when cut to length.
Example Sentence 2
Inspect the preformed cable runs for broken strands after any hard landing that stressed the controls.