Definition
A threaded fastener bent into the shape of the letter U, with both ends threaded to accept nuts. It is used to clamp a round or square object — such as a tube, cable bundle, or structural member — against a flat surface or bracket without drilling through the object itself.
Plain English
A bolt shaped like the letter U, with threads on both ends. You loop it around a pipe or rod, push the two ends through a plate, and tighten a nut on each end to hold the pipe firmly in place.
Context Anchor
Seen in aircraft maintenance, especially when inspecting clamps, mounts, brackets, and hardware that hold round parts securely.
Derivation
Named for its shape — the bolt is bent into the form of the capital letter U. The name describes the part directly.
Why Pilots Care
A loose or missing U-bolt can allow critical cables or lines to chafe or shift, leading to control problems or system failure.
Intuition Check
Do not think of a U-bolt as just a regular straight bolt. Its purpose is to wrap around a part and clamp it in place.
Example Sentence 1
The mechanic used a U-bolt to secure the exhaust pipe to the support bracket.
Example Sentence 2
During the annual inspection the IA checked the torque on every U-bolt holding the brake lines.