Commonwealth legislation

AD/ALF/13 - Third Stage Compressor Disc Inspection

In ForceCTH

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

3/10 complexity

This directive requires owners/operators and maintenance organisations of Textron‑Lycoming ALF 502 L and R series engines to inspect specified third‑stage compressor discs (effective 1 Jan 1994). Inspections must follow the manufacturer’s service bulletins cited by the AD because Sermetel W coating applied to some discs may flake, allowing corrosion and risking disc failure. Compliance shifts inspection and repair costs and procedural detail to operators and the Textron‑Lycoming service instructions.

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Current sections

Direct links to the current provisions in AD/ALF/13 - Third Stage Compressor Disc Inspection.

AD/ALF/13 - Third Stage Compressor Disc Inspection

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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AlliedSignal (Lycoming) Turbine Engines - ALF502 and LF507 Series

AD/ALF/13 Third Stage Compressor Disc Inspection 13/93

Applicability: All Textron-Lycoming ALF 502 L and R series engines incorporating 3rd stage compressor discs as detailed the Requirement documents.

Requirement: Inspect affected 3rd stage compressor discs in accordance with Textron-Lycoming Service Bulletins ALF 502L 72-259 or ALF 502R 72-259 as applicable.

Note: FAA AD 93-10-07 also refers.

Compliance: Effective 1 January 1994. As detailed in the Requirement Documents.

Background: A number of 3rd stage compressor discs have been identified where the Sermetel W protective coating may be defective due to improper surface preparation. This can lead to lack of adhesion and subsequent flaking of the coating. Degraded coating can result in corrosion of the disc and potential disc failure.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/ALF/13 - Third Stage Compressor Disc Inspection