EASA SIB NE-10-07: TCM series engines - identify the cylinder assemblies

What to do

Operators and maintenance facilities should check engine records for Superior Air Parts cylinder assemblies and visually inspect the cylinder head markings by removing the valve cover if the part number is not visible on the cylinder flange. If the markings 'AMCAST' or 'CP' with revision letters are present along with part numbers SAC 52001 I or SAC 55001 I, the cylinder assembly is affected by AD 2009-16-03 and should be inspected accordingly. No new compliance deadlines are specified in this bulletin.

Summary

The Special Airworthiness Information Bulletin titled 'TCM series engines - identify the cylinder assemblies' provides identification guidance for certain Superior Air Parts investment cast cylinder assemblies installed on Teledyne Continental Motors IO-520, TSIO-520, and IO-550 series engines. It informs owners, operators, and repair facilities about markings that help identify affected cylinder assemblies related to Airworthiness Directive 2009-16-03. The bulletin clarifies foundry and revision markings on these cylinder heads to assist in compliance and maintenance.

What changed

This bulletin updates the identification criteria for affected cylinder assemblies by adding that the cylinder heads may bear the letters 'CP' and revision markings instead of the previously noted 'AMCAST' marking. It provides tables detailing foundry markings and manufacturing dates to aid in recognizing affected parts without removal from the engine. This is an informational update complementing AD 2009-16-03 rather than a new regulatory requirement.

Why it matters

Accurate identification of affected cylinder assemblies is critical for compliance with AD 2009-16-03 and ensuring continued airworthiness of TCM IO-520, TSIO-520, and IO-550 series engines. Operators and maintenance personnel can avoid unnecessary disassembly by using the updated marking information, improving efficiency and safety. This helps maintenance teams verify if their engines have potentially affected parts that require inspection or further action.