EASA SIB AIR-21-07
Piper PA-28 and PA-32 aeroplanes - Verification of Correct Washers used with Wing Spar Attach Bolts
Summary
The FAA Special Airworthiness Information Bulletin AIR-21-07 addresses the verification of correct washers used with wing spar attach bolts on Piper PA-28 and PA-32 aeroplanes. This bulletin provides guidance related to compliance with Airworthiness Directive 2020-26-16, focusing on the proper washer style to ensure structural clearance. It highlights issues with incorrectly manufactured washers that lack the required rounded edges.
What Changed
This bulletin introduces a recommendation for owners and operators to verify that Piper part number 96352-003 washers have the required rounded edge on one side before installation with wing spar attach bolts. It identifies a manufacturing discrepancy where washers marked with the correct part number may not have the proper design, potentially affecting structural clearance. The bulletin does not mandate changes but advises caution during maintenance.
Why It Matters
Ensuring the correct washer style is critical to maintaining proper clearance between the washer and wing spar structure, which affects the structural integrity of the wing attachment. Incorrect washers could compromise the fit and potentially impact the airworthiness of the aircraft. Operators, maintenance personnel, and compliance teams must be aware of this issue to avoid installation errors and ensure continued safe operation of affected Piper PA-28 and PA-32 aircraft.
What To Do
Owners and operators should inspect any received Piper washers with part number 96352-003 intended for wing spar attach bolts to confirm the presence of the required rounded edge. If washers lack the proper radius, they must not be installed, and correct washers should be obtained before proceeding. This verification should be performed when complying with AD 2020-26-16, with no specific deadline beyond that compliance requirement.