{"id":"F2006B08644","name":"AD/CON/67 - Valve Retainer Key","slug":"ad-con-67-valve-retainer-key","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51688,"registerId":"commonwealth-F2006B08644-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CON/67 - Valve Retainer Key","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nTeledyne Continental Motors Piston Engines\n\nAD/CON/67 Valve Retainer Key 8/93 DM\n\nApplicability: All engines manufactured/remanufactured/overhauled by Teledyne Continental Motors (TCM) in the period July 29 1992 and March 30 1993, as listed by serial number in TCM mandatory service bulletin (MSB) No. 93-12, dated MAY 12 1993, which have less than 25 hours TIS since installation, and all Cylinder assemblies supplied by TCM between JULY 29 1992 and MARCH 30 1993, which have less than 25 hours TIS since installation.\n\nRequirement: Verify proper valve retainer key installation in accordance with TCM Mandatory Service Bulletin No. MSB 93-12.\n\nNote: FAA Airworthiness Directive 93-10-02 refers.\n\nCompliance: Effective June 7 1993; unless previously accomplished, before further flight.\n\nBackground: This Directive has been issued to require an inspection of certain TCM engines and cylinders for correct assembly of the valve retainer keys. The requirement follows advice of two overseas events in which missing valve retainer keys resulted in engine failure.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text sets a clear, limited scope: specified TCM engines and cylinders supplied between 29 July 1992 and 30 March 1993 with under 25 hours TIS must be inspected per MSB 93-12 before further flight. The instrument itself does not indicate any amendment or expansion of that scope."},"complexity_factors":["Narrow temporal and serial-number applicability requiring cross-check against TCM MSB No. 93-12 (Applicability).","Conditional threshold (\"less than 25 hours TIS\") requires record checks to determine who is affected (Applicability).","Immediate, mandatory compliance \"before further flight\" creates potential operational disruption and short timelines for inspection (Compliance).","Procedure and verification steps are delegated to an external document (TCM MSB 93-12), so compliance depends on following that bulletin (Requirement).","Reference to FAA AD creates a need for alignment with overseas directives and may involve multi-jurisdictional information flow (Note/Background)."],"plain_english_summary":"Mechanically, this airworthiness directive requires operators of Teledyne Continental Motors engines or TCM‑supplied cylinders manufactured, remanufactured, overhauled or supplied between 29 July 1992 and 30 March 1993 with under 25 hours TIS to have valve retainer key installation verified according to TCM Mandatory Service Bulletin MSB 93‑12. The inspection must be done before further flight and is the responsibility and cost of aircraft owners/operators and maintenance organisations (Applicability; Requirement; Compliance). It follows two overseas engine failures linked to missing keys (Background)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete airworthiness directive with a narrow, specific safety purpose. It has not expanded beyond its original intent of addressing a known manufacturing defect in specific engine batches."},"complexity_factors":["Single, specific applicability criteria based on date ranges and serial numbers","One clear compliance requirement referencing an external technical document (MSB 93-12)","No defined terms section","No cross-references to other legislation beyond a note about the related FAA directive","Simple conditional logic: applies if manufactured in date range AND less than 25 hours TIS (Time In Service)","Length: approximately 200 words"],"plain_english_summary":"This CASA safety order mandates urgent inspections of certain Teledyne Continental Motors piston engines and replacement cylinders built, rebuilt or overhauled between 29 July 1992 and 30 March 1993 (with less than 25 flight hours since installation) to confirm valve retainer keys are correctly installed. It follows two overseas incidents where missing keys led to complete engine failures, and compliance — using TCM Service Bulletin MSB 93-12 — is mandatory before flight, with a deadline of 7 June 1993 (or immediately before next flight if not yet done)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-con-67-valve-retainer-key","history":"/api/acts/ad-con-67-valve-retainer-key/history","analysis":"/api/acts/ad-con-67-valve-retainer-key/analysis","conflicts":"/api/acts/ad-con-67-valve-retainer-key/conflicts","importantCases":"/api/acts/ad-con-67-valve-retainer-key/important-cases","documents":"/api/acts/ad-con-67-valve-retainer-key/documents"}}