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Based on your new, more rigorous requirements, here is the deeply researched, highly technical, and SEO-optimized product description for the Textron Aviation 6641649-7.
6641649-7 – Textron Aviation OEM Pivot Link Pin
Available now on the Airparts.aero Marketplace.
Overview
The Textron Aviation 6641649-7 is a flight-critical, OEM pivot link pin, a primary structural component of the main landing gear (MLG) shock strut for the Cessna Citation 560XL family of business jets. This is not a standard bolt or pin; it is a precision-ground, ultra-high-strength steel pin engineered to serve as a primary pivot point within the landing gear's complex kinematic linkage. The 6641649-7 is designed to handle immense shear and bending loads during landing, taxiing, and gear retraction/extension, while allowing for smooth, binding-free articulation of the gear's structural members.
As a genuine Textron OEM part, its material integrity, heat treatment, and microscopic dimensional tolerances are certified to be of the highest standard. Its flawless performance is fundamental to the structural integrity and reliable operation of the entire landing gear assembly.
Key Features
Primary Structural Pivot: Functions as a major load-bearing pivot pin, connecting key structural elements of the main landing gear strut, such as the drag brace or side brace linkages. It is designed to carry the immense shear loads of landing and the tensile/compressive loads of the retraction system.
Ultra-High-Strength VAR Steel: Machined from an ultra-high-strength, vacuum-arc remelt (VAR) steel alloy, such as 300M. This premium alloy is chosen for its exceptional toughness, high tensile strength (in the 280-305 KSI range), and superior resistance to fatigue crack propagation.
Hard Chrome Plating: The entire surface of the pin is plated with a thick, hard layer of chrome. This provides an extremely durable, low-friction, and corrosion-resistant surface for the mating bearings or bushings to pivot on, ensuring a long and reliable service life.
Precision Centerless Grinding: After heat treatment and plating, the pin is precision centerless ground to an extremely tight dimensional tolerance, often measured in ten-thousandths of an inch. This ensures a perfect, press-fit or close-tolerance fit, eliminating play in the joint.
Non-Destructive Tested (NDT): As a flight-critical structural component, each pin is subjected to 100% Non-Destructive Testing, such as Magnetic Particle Inspection (MPI), to guarantee it is completely free from any microscopic cracks or material flaws.
Technical Specifications
Part Number: 6641649-7
Component Type: Main Landing Gear Structural Pivot Pin
Material: Ultra-High-Strength VAR Steel Alloy (e.g., 300M)
Finish: Hard Chrome Plating
Primary Function: Provides a high-strength pivot point for MLG structural linkages.
Inspection: 100% NDT Inspected; serialized and fully traceable.
Certification: FAA Production Approval
Aircraft Compatibility
The 6641649-7 is a specific structural component for the main landing gear of the highly successful Cessna Citation 560XL family. It is imperative to consult the specific aircraft's Illustrated Parts Catalog (IPC) for final verification.
Primary Aircraft Models:
Cessna Citation Excel
Cessna Citation XLS & XLS+
Why Choose 6641649-7?
The failure of a primary landing gear pivot pin during landing would be catastrophic, leading to an immediate gear collapse. The Textron Aviation 6641649-7 is the only component certified by the manufacturer to provide the required material strength, hardness, and fatigue life for this critical application. Using a genuine OEM part is the only way to ensure you are installing a pin with a known, traceable manufacturing history, made from the correct, certified materials, and proven to be free of defects through rigorous NDT inspection.
The 6641649-7 pivot link pin is a classic example of a fastener designed to operate in double shear. It passes through a central bearing or lug and is supported by two outer lugs on the mating structure. This arrangement is inherently stronger and more stable than a single-shear joint. The hard chrome plating on the pin's surface serves two critical functions: it provides a sacrificial, low-friction surface for the bearing to rotate on, preventing wear of the base metal, and its high hardness (typically >65 HRC) and compressive residual stress significantly increase the pin's resistance to fatigue crack initiation. The entire component is a life-limited part whose service history must be meticulously tracked, as it is designed to be replaced after a specific number of landing cycles to preempt any possibility of a fatigue failure.
Note: This is a flight-critical, serialized, and life-limited primary structural component. Installation and removal require specialized tooling and must be performed by a certified AME or A&P mechanic at a qualified Part 145 repair station with the appropriate structural ratings, in strict accordance with the current Textron Aviation maintenance manual.
