Piper PA-31 Navajo — Systems Description

This document is a service bulletin for the Piper PA-31-310 and PA-31-325 Navajo aircraft, detailing mandatory inspections and maintenance procedures. It specifically addresses Airworthiness Directives (ADs) that apply to serial numbers 31-2 through 31-8312019. The bulletin outlines the necessary inspections for exhaust couplings, tailpipes, and rudder torque tubes, emphasizing the importance of regular checks to ensure safety and compliance with regulatory standards. The document serves as a critical reference for maintenance personnel and pilots to maintain the airworthiness of these aircraft models.

• Mandatory inspection of exhaust couplings every 100 hours of operation.
• Rudder torque tube inspections required every 12 months for corrosion.
• Specific part numbers for exhaust system components are provided for maintenance.
• Tailpipes must be inspected for internal pitting and wall thickness.