AN3-4A - Textron Aviation OEM Hex Head Machine Bolt

AN3-4A – Textron Aviation OEM 10-32 x 1/2" Hex Head Bolt

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Overview

The AN3-4A is a high-strength hex head bolt that holds dual authority as a component built to the exacting Air Force-Navy (AN) standard and as a genuine Textron Aviation Original Equipment Manufacturer (OEM) part. This short-body fastener, with its 3/16-inch diameter and 1/2-inch length, is a workhorse for assembling thin-gauge materials, clamps, and small brackets. Its "A" designation signifies an undrilled shank, making it the standard for use with self-locking nuts in a vast array of tension and shear applications.

As a component supplied through the Textron Aviation channel, this AN3-4A bolt comes with the full assurance of OEM traceability and quality control. It is guaranteed to be the factory-specified hardware for maintaining the type-certified design and integrity of Cessna, Beechcraft, and Hawker aircraft, fabricated from the correct alloy steel and finished with a protective cadmium plating.

Key Features

• Textron Aviation OEM Certified: Supplied with the full traceability and quality assurance of Textron Aviation, guaranteeing it is the correct, factory-approved part for their fleet.

• High-Tensile Alloy Steel: Forged from premium alloy steel and heat-treated to a minimum tensile strength of 125,000 PSI for maximum joint strength.

• Cadmium Plating: Coated with a sacrificial cadmium layer per QQ-P-416 for exceptional corrosion resistance and a consistent, low-friction bearing surface.

• Rolled Threads: Features #10-32 UNF-3A threads that are cold-rolled, a superior manufacturing process that significantly increases fatigue resistance.

• Short Grip Design: A 1/8-inch grip length makes this bolt ideal for securing thin materials without excess threads protruding, ensuring a proper fit.

• AN Standard Compliance: Fully conforms to the AN3 specification, ensuring the highest level of quality control for materials and dimensions.

Technical Specifications

• Part Number: AN3-4A

• Component Type: Hex Head Machine Bolt

• OEM Authority: Textron Aviation

• Governing Specification: AN3 / NASM3

• Material: Alloy Steel (e.g., 4140, 8740), heat-treated

• Minimum Tensile Strength: 125,000 PSI

• Finish: Cadmium Plate per QQ-P-416, Type II, Class 2

• Diameter: 3/16 inch (0.1875 inches)

• Nominal Length (under head to end): 1/2 inch (0.500 inches)

• Grip Length (Unthreaded Shank): 1/8 inch (0.125 inches)

• Thread Specification: #10-32 UNF-3A

Aircraft Compatibility

As a Textron Aviation OEM part, this fastener is specified in numerous locations across their entire product line. As an AN-standard bolt, its use is ubiquitous throughout the aerospace industry.

• Primary Textron Aviation Platforms:

  • Cessna Piston Aircraft (172, 182, 206, etc.)

  • Beechcraft Piston Aircraft (Bonanza, Baron)

  • Cessna and Beechcraft Turboprops (Caravan, King Air)

  • Cessna Citation Business Jets

  • Hawker Business Jets

• General Aerospace Usage: Used in virtually every class of aircraft for myriad applications requiring a short-grip 3/16" bolt.

Note: Verification of applicability is the responsibility of the installer. The grip length must be appropriate for the material thickness being joined. Always consult the current version of the aircraft's Illustrated Parts Catalog (IPC) or maintenance manual to confirm part number eligibility.

Applications

• Attaching clamps (P-clamps) for fluid lines, electrical harnesses, and conduits.

• Securing small brackets, inspection covers, and instrument panels.

• Fastening firewall seals, gaskets, and thin sheet metal components.

• Assembling interior panels and secondary structures.

Why Choose this AN3-4A?

This component provides the dual assurance of meeting the public AN aerospace standard and the specific endorsement of Textron Aviation. This guarantees the bolt's mechanical properties, from the chemistry of its steel to the fatigue-resistance of its rolled threads. Using commercial-grade hardware in an aircraft application introduces an unacceptable risk of material fracture and joint failure. By choosing this OEM-certified AN bolt, you ensure the use of a traceable, airworthy component that maintains the aircraft's original design integrity.

The designation "Textron Aviation OEM" signifies more than just a supply channel; it represents a documented chain of custody and quality assurance that is critical for certified aircraft. While a fastener may be manufactured to the AN3-4A standard, an OEM-sourced part provides an unbroken line of traceability back to a manufacturer audited and approved under rigorous aerospace quality systems like AS9100. Each lot is accompanied by a Certificate of Conformance (C of C) that verifies the specific material heat lot, the date of manufacture, the results of destructive and non-destructive testing, and its conformity to all aspects of the governing specification. This documented proof is essential for airworthiness and is the fundamental difference between a generic part that "meets the spec" and a certified OEM component that provably is the spec.

Note: This is a flight-critical hardware component. Installation must be performed by a certified mechanic. A calibrated torque wrench must be used to apply the correct torque value specified in the maintenance manual to achieve proper clamp load (preload). This bolt must be paired with a corresponding certified aerospace-grade self-locking nut (e.g., MS21044N3 or MS21045N3) to ensure the joint remains secure.

Documentation

The base standard for this part is maintained under the National Aerospace Standards (NASM). OEM-specific application and installation data is contained within the Textron Aviation maintenance and parts manuals.