Piper PA-30 Twin Comanche — Service Bulletins

This document is a service bulletin addressing the potential for corrosion in the wing spar caps of the Piper PA-30 and PA-39 Twin Comanche aircraft. It highlights the importance of inspecting the internal wing structure for corrosion caused by exhaust gases, which can lead to significant structural issues if left unchecked. The bulletin provides specific recommendations for inspections to be performed at each scheduled aeroplane inspection, emphasizing the need for detailed attention to the areas most susceptible to corrosion. The document serves as a critical reminder for operators and maintainers to adhere to inspection protocols to ensure aircraft safety and integrity.

• Inspect wing spar caps at each 100-hour inspection.
• Corrosion can reduce structural integrity and fatigue life.
• Pay special attention to the forward flange leading edge of the spar caps.
• Use a mirror and bright light for thorough inspection.
• Report any corrosion findings to CASA with detailed information.