AN3-5A – Textron Aviation OEM 10-32 x 5/8" Hex Head Bolt
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Overview
The AN3-5A 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 ubiquitous fastener, with its 3/16-inch diameter and 5/8-inch length, is a workhorse in aircraft assembly and maintenance. 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 AN3-5A 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.
Undrilled Shank ("A" Type): Designed for use with self-locking nuts (e.g., MS21044N3, MS21045N3), providing secure fastening without the need for a cotter pin.
AN Standard Compliance: Fully conforms to the AN3 specification, ensuring the highest level of quality control for materials and dimensions.
Technical Specifications
Part Number: AN3-5A
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): 5/8 inch (0.625 inches)
Grip Length (Unthreaded Shank): 1/4 inch (0.250 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.
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
Assembly of engine baffling, cowlings, and fairings.
Mounting of systems hardware, brackets, and line clamps.
Securing of inspection panels, access covers, and interior components.
Use in secondary structural connections as specified by engineering drawings.
Why Choose this AN3-5A?
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 cadmium plating on an AN3-5A bolt, specified under QQ-P-416, serves a critical tribological function beyond mere corrosion resistance. The primary goal of torquing a fastener is to achieve a specific axial tension, or preload. This relationship is highly dependent on the coefficient of friction at the thread and under-head bearing surfaces. Cadmium provides a soft, lubricious surface with a consistent and well-documented coefficient of friction. This consistency is the reason that torque tables in maintenance manuals are standardized for cadmium-plated hardware. It ensures that when a mechanic applies a specified torque value with a calibrated wrench, a predictable and accurate amount of that energy is converted into the clamp force required to secure the joint, while a known amount is used to overcome friction. Using a fastener with a different plating (like zinc) or no plating would introduce a different, often higher, coefficient of friction, resulting in a dangerously under-loaded joint for the same applied torque.
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.