Piper PA-31 Navajo Chieftain — Type Certificate

This document is a Supplemental Type Certificate (STC) issued by the Australian Civil Aviation Safety Authority for modifications applicable to the Piper PA-31 series aircraft. It certifies the installation of a wing spar strap and an inspection program aimed at extending the life of the wing main spar lower cap for various models of the Piper PA-31, including the PA-31-300, PA-31-325, and PA-31-350. The STC outlines the conditions under which these modifications can be made and specifies the serial numbers of eligible aircraft. The document is intended for aircraft owners, maintenance personnel, and operators who need to ensure compliance with airworthiness requirements and the ongoing inspection program. It includes details on the certification basis, approved modification data, and the responsibilities of the certificate holder.

• This STC is applicable to Piper PA-31 series aircraft including models PA-31, PA-31-300, PA-31-325, and PA-31-350.
• Eligible serial numbers for PA-31 models start from 31-2, while PA-31-350 starts from 31-5001.
• The modifications include the installation of a wing spar strap and an inspection program for the wing main spar lower cap.
• The certification basis includes compliance with Civil Aviation Order 101.22 Issue 4 and FAA CAR 3 at amendment 8.
• The document specifies the responsibilities of the certificate holder regarding modifications and inspections.