EASA SIB 2008-87
AgustaWestland AW139 Detailed Inspection of Tail Rotor Damper spherical bearings for condition, damage and play.
Summary
EASA Safety Information Bulletin SIB No. 2008-87 provides guidance on the detailed inspection of the tail rotor damper spherical bearings for condition, damage, and play on all AgustaWestland AW139 helicopters. The bulletin references AgustaWestland Information Letter No. AW139-08-006 and emphasizes proper compliance with the Aircraft Maintenance Planning Information Chapter 04 Certification Maintenance Requirement CM64-01. The inspection ensures the tail rotor damper rod end bearing functions correctly to maintain the proper load path and avoid rod end seizure.
What Changed
This bulletin introduces a detailed inspection procedure for the tail rotor damper spherical bearings on AgustaWestland AW139 helicopters, highlighting the importance of measuring exact bearing play values rather than using qualitative methods. It reinforces adherence to the AMP Data Module 39-A-64-21-00-00A-286A-A and recommends maintaining local records of inspection measurements for historical tracking.
Why It Matters
Proper inspection and measurement of the tail rotor damper bearings are critical to prevent rod end seizure, which can compromise helicopter safety and performance. For operators, maintenance organizations, and compliance teams, following the specified procedures ensures continued airworthiness and reduces the risk of unexpected failures related to the tail rotor system.
What To Do
Operators and maintenance personnel should perform the inspection task CM64-01 as detailed in the AgustaWestland Aircraft Maintenance Publication procedure 39-A-64-21-00-00A-286A-A. They should record exact bearing play values using local electronic or paper tables to maintain historical records. No explicit compliance deadline is stated, but timely adherence to these recommendations is advised to ensure safety.
AI-generated summary from official EASA source document. Always verify against the original.