487-704 - Piper Aircraft OEM Cowl Turnlock Stud Assembly

487-704 – Piper Aircraft OEM Cowl Turnlock Stud Assembly

Available now on the Airparts.aero Marketplace.

Overview

The Piper Aircraft 487-704 is a genuine OEM cowl turnlock stud assembly, a flight-critical fastener engineered specifically for securing the engine cowlings on a wide range of Piper aircraft. This is not a simple screw; it is the male component of a quick-acting, quarter-turn fastener system that provides both secure locking and rapid access to the engine compartment. Manufactured from high-strength, cadmium-plated steel, the 487-704 is designed to withstand constant vibration and aerodynamic loads while allowing for efficient removal and installation of the cowling during pre-flight inspections and maintenance.

Key Features

• Quick-Acting Quarter-Turn Design: Allows for extremely fast locking and unlocking of the engine cowling. A simple 90-degree turn with a screwdriver engages or disengages the stud from its receptacle, dramatically reducing the time and effort required for engine access compared to standard screws.
• Positive Locking Mechanism: The stud's cross-pin is designed to engage with a cammed receptacle on the airframe, creating a positive lock that is highly resistant to loosening from engine and airframe vibration.
• Flush Head for Aerodynamics: Features a flush, countersunk-style head that, when installed, sits level with the surface of the cowling. This is essential for maintaining a smooth aerodynamic profile and reducing parasitic drag.
• High-Strength Steel Construction: Fabricated from a high-strength steel alloy to provide the durability needed to withstand repeated use and the tensile loads required to hold the cowling securely against its seals.
• Corrosion-Resistant Plating: Plated with a durable cadmium finish to provide robust protection against corrosion from moisture and the harsh environment of the engine compartment.

Technical Specifications

• Part Number: 487-704
• Component Type: Cowl Turnlock Fastener Stud
• Head Style: Flush Head
• Drive Type: Slotted / Phillips Combination Recess
• Material: Steel Alloy
• Finish: Cadmium Plated
• Grip Length: This stud has a specific grip length (the distance from the head to the locking pin) designed for the exact thickness of the cowling panel.
• Certification: FAA Production Approval

Aircraft Compatibility

The 487-704 is the standard OEM cowling fastener for a significant portion of the Piper piston aircraft fleet. It is imperative to consult the specific aircraft's Illustrated Parts Catalog (IPC) for final verification.

• Primary Aircraft Families:
  • PA-28: Archer, Warrior, Dakota
  • PA-28R: Arrow
  • PA-32: Cherokee Six, Lance, Saratoga
  • PA-34: Seneca
  • PA-44: Seminole

Applications

The 487-704 has a singular, but highly critical, application:

• Engine Cowling Fastening: Its sole purpose is to securely fasten the engine cowling panels to the aircraft's firewall and support structure.
• Pre-Flight & Maintenance Access: Provides pilots and mechanics with rapid and reliable access to the engine compartment for essential pre-flight inspections and routine maintenance.

Why Choose 487-704?

The security of the engine cowling in flight is paramount. A cowling panel that departs the aircraft can cause catastrophic damage to the empennage or flight controls. The Piper 487-704 is the genuine OEM part engineered with the correct materials, strength, and grip length to safely secure the cowling as intended by the manufacturer. Using non-certified or incorrect-length fasteners can lead to excessive vibration, panel fretting, or a complete failure of the fastening system. For a component this critical to safety, trust only genuine Piper OEM parts.

Website Metadata

• Meta Title: 487-704 Piper Aircraft Cowl Fastener Stud | OEM Turnlock | Airparts.aero
• Meta Description: Purchase the genuine Piper Aircraft 487-704 cowl turnlock stud assembly. A flight-critical, flush-head, quarter-turn fastener for securing engine cowlings on PA-28, PA-32, and other Piper models.
• SEO and Plain Text Keywords: 487-704, Piper parts, cowl fastener, turnlock fastener, cowling stud, quarter turn stud, aircraft fastener, PA-28 parts, Archer parts, Saratoga parts, Seneca parts, OEM Piper parts, Airparts.aero.

Order Your 487-704 Cowl Studs Now

Ensure your aircraft's cowling is secure with genuine, flight-critical Piper OEM hardware. Visit Airparts.aero to order your 487-704 cowl turnlock studs today.

SEO-Enhanced Addendum

The 487-704 turnlock stud operates as part of a cam-and-pin fastener system. The stud's cross-pin engages with a cammed receptacle mounted on the fixed airframe structure. As the stud is turned 90 degrees, the pin rides up the receptacle's cam track. This action provides a powerful "pull-up" or clamping force, drawing the cowling tight against its supports. At the end of the rotation, the pin drops into a detent, which provides the positive lock that resists vibration. The most critical dimension for this system to work correctly is the stud's "grip length." This must be precisely matched to the thickness of the cowling panel material to ensure the cross-pin is properly positioned within the receptacle's cam, achieving the designed clamping force without being too loose or too tight.

Note: This is a flight-critical component. The selection of the correct stud grip length is essential for a secure installation. This part should be installed in conjunction with the proper grommet in the cowling panel to prevent wear. Always inspect receptacles for wear when replacing studs.