Cessna 188 AGwagon — Service Bulletins

This service bulletin from Hartzell Propeller Inc. addresses the inspection and maintenance requirements for specific propeller hubs used on various aircraft, including the Cessna 188 AGwagon. It outlines the procedures for inspecting the propeller hub fillet radius to detect cracks that could lead to catastrophic failures. The bulletin is particularly relevant for hubs manufactured before April 1997 and those with specific serial number suffixes. It emphasizes the importance of regular inspections and provides guidelines for replacing hubs that do not meet safety standards. This document is essential for operators and maintenance personnel to ensure the safety and airworthiness of affected aircraft.

• Initial eddy current inspection required within 50 hours of operation for affected hubs.
• Subsequent inspections must not exceed 150 hours of operation.
• Hubs without 'A' or 'B' suffixes must be replaced with the latest design hubs.
• Immediate inspection is required if unexplained vibrations or grease leakage occur.
• Cracked hubs must be replaced before further flight.