553-877 - Piper Aircraft OEM Cabin Door Latch Cam Supersedes 63042-003

553-877 – Piper Aircraft Cabin Door Latch Cam (Replaces 63042-003)

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The 553-877 is the current production, genuine Piper Aircraft OEM part number for the main cabin door latch cam. This part directly replaces and supersedes the previous part number 63042-003. This cam is the mechanical heart of the latching system; it is a precisely machined component that translates the rotational motion of the interior and exterior door handles into the linear motion of the latch bolts or hooks.

The proper function of this cam is essential for ensuring the main cabin door can be opened easily on the ground and, more critically, is securely latched and locked in flight. Fabricated from a high-strength, hard-anodized aluminum alloy, this component is designed for a long service life. However, after thousands of operational cycles, wear on the cam profile can lead to improper latch engagement. Replacing a worn cam with the current, genuine Piper 553-877 part is the definitive way to restore the positive, secure feel and function of the aircraft's door latching system to the latest standard.

Key Features

• Genuine Piper Aircraft OEM Part: The current, factory-authorized part, ensuring you receive the latest production revision and full compliance with the aircraft's type certificate.

• Direct Replacement for 63042-003: Engineered as a direct, form-fit-function replacement for the previous part number.

• Precision-Machined Cam Profile: Ensures the correct "throw" to fully retract and extend the door latching bolts for a secure, positive latch.

• High-Strength Anodized Aluminum Alloy: Manufactured from a durable, heat-treated aluminum alloy with a hard-anodized surface for superior wear and corrosion resistance.

• Critical for Door Security: The integrity of this component is fundamental to the security of the main cabin door in all phases of flight.

Technical Specifications

• Part Number: 553-877

• Supersedes: 63042-003

• Component Type: Cabin Door Latch Cam

• OEM Manufacturer: Piper Aircraft, Inc.

• Material: High-Strength Aluminum Alloy (e.g., 2024-T4 or 7075-T6), Hard Anodized Finish (Material must be confirmed by OEM documentation).

Aircraft Compatibility

The 553-877 is the specified latch cam for the main cabin door on a vast range of Piper's most popular single-engine and light-twin aircraft. Common applicable models include, but are not limited to:

• PA-28 Series: Cherokee, Warrior, Archer, Arrow, Dakota

• PA-32 Series: Cherokee Six, Lance, Saratoga

• PA-34 Series: Seneca

Crucial Note: The specific aircraft model and serial number must be checked against the latest revision of the official Piper Aircraft Illustrated Parts Catalog (IPC) to ensure correct part number applicability.

Applications

• Located in the main cabin door latching mechanism, typically at the aft edge of the door.

• Replacement part for worn, cracked, or damaged cams to resolve issues with door latch operation, rigging, and security.

Why Choose 553-877?

The security of the main cabin door in flight is a critical safety item. A worn latch cam can prevent the latching bolts from fully engaging, creating the potential for an in-flight door opening. Using the genuine Piper 553-877 replacement part guarantees you are installing the latest, certified revision of this component. This ensures the correct cam geometry and material strength required for a secure and airworthy repair, restoring the latching system to its original type design and providing the highest level of safety.

The 553-877 functions as a plate cam within a cam-and-follower mechanical system. Its precisely contoured outer profile serves as the driving surface that dictates the motion of the entire latch mechanism. The linkage connected to the latching bolts contains a follower, typically a roller or pin, that rides along this profile. As the door handle rotates the cam, the follower is forced to move radially inward or outward according to the cam's engineered geometry—a motion path defined by a specific displacement diagram. The rate of this displacement (the "throw") and the mechanical advantage of the system are determined by the cam profile's slope at any given point. Wear on this critical surface, caused by thousands of cycles of sliding contact, alters the displacement diagram, leading to incomplete latch retraction (a door that won't open) or insufficient extension (a door that won't securely close). The use of a high-strength aluminum alloy with a Type III hardcoat anodized surface provides the necessary wear resistance for this high-cycle, critical-function application.

Note: This is a flight-critical component directly related to the security of the main cabin door. Replacement should only be performed by a certified A&P mechanic. After installation of a new cam, the entire door latching, locking, and emergency exit mechanism must be functionally tested and rigged in strict accordance with the Piper Maintenance Manual for the specific aircraft model to ensure positive latching and proper engagement.

Documentation

The definitive part number applicability and all installation and rigging procedures are detailed in the applicable Piper Aircraft Illustrated Parts Catalog (IPC) and Maintenance Manual for the specific aircraft model and serial number.