McFarlane MS21251-B5S Turnbuckle Barrel (Brass) is a precision aircraft hardware component designed for use in turnbuckle assemblies that enable accurate tension adjustment of aircraft control cables. Manufactured to MS21251 military specifications, this brass barrel serves as the central adjustment mechanism, allowing compatible left-hand and right-hand threaded terminals to be simultaneously adjusted for precise cable rigging.

The turnbuckle barrel is an essential part of flight control cable systems, where maintaining proper cable tension is critical for accurate control surface movement, system responsiveness, and overall aircraft safety. Its precision-machined internal threads ensure smooth adjustment while providing secure engagement with compatible turnbuckle terminals. Once the desired tension is achieved, the assembly is secured using an approved locking clip or other specified safetying method.

Constructed from high-quality brass, the MS21251-B5S offers excellent corrosion resistance, smooth thread operation, and resistance to thread galling. The durable construction is designed to withstand repeated rigging adjustments and long-term exposure to demanding aviation operating environments.

Regular maintenance should include inspection of the barrel for thread wear, corrosion, deformation, and proper safetying to ensure continued reliability and airworthiness of the aircraft control cable system.

Key Features

- Part Number: MS21251-B5S
- Manufacturer: McFarlane Aviation
- Component: Turnbuckle Barrel (Brass)
- Specification: MS21251 military standard
- Material: Brass
- Designed for aircraft flight control cable turnbuckle assemblies
- Precision-machined internal threads for accurate cable tension adjustment
- Excellent corrosion resistance and smooth thread engagement
- Suitable for repeated maintenance and rigging procedures in aviation applications