{"id":"F2006B08649","name":"AD/CON/73 - Unapproved Camshaft Repairs","slug":"ad-con-73-unapproved-camshaft-repairs","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51709,"registerId":"commonwealth-F2006B08649-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CON/73 - Unapproved Camshaft Repairs","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/73 Unapproved Camshaft Repairs 3/95\n\nApplicability: All Teledyne Continental Motors piston engine camshafts repaired by Wades Camshafts Pty Ltd, North Melbourne Victoria, prior to 31 October 1994.\n\nRequirement: Inspect applicable camshafts for lobe profile, lobe dimensions and grinding stress induced thermal cracks in accordance with an appropriate CAR 35 approved camshaft repair procedure.\n\nCompliance: Effective 2 March 1995.\n\nInstalled camshafts: At the next engine overhaul or bulk strip, whichever occurs first. Spare camshafts: Prior to installation in an engine.\n\nBackground: This Directive has been issued to address advice of camshafts being repaired contrary to the requirements of CAO 106, AD/ENG/4 Amdt. 3, Paragraph 2.4. A number of the applicable camshafts have been examined at the Authority's Materials Evaluation Facility in Canberra. The examination indicates the Wades Camshafts repair procedure does not degrade the airworthiness of the subject camshaft. Therefore, applicable camshafts may remain in service until the next access to the affected part.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1517},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This remains a targeted airworthiness directive addressing a specific non-compliance issue with a defined set of engine components. It has not expanded beyond its original purpose of ensuring the safety of camshafts repaired by a specific vendor during a specific timeframe."},"complexity_factors":["Technical aviation terminology (camshaft lobe profiles, thermal cracks, bulk strip)","References to multiple regulatory instruments (CAR 35, CAO 106, AD/ENG/4)","Specific applicability criteria requiring date and supplier verification","Distinction between installed and spare parts with different compliance timelines"],"plain_english_summary":"This directive requires inspections of specific aircraft engine camshafts (the parts that control valve timing) that were repaired by a particular Melbourne workshop before November 1994.\n\n**Who it affects**: Owners and operators of aircraft with Teledyne Continental Motors piston engines, specifically those that had camshafts repaired by Wades Camshafts Pty Ltd in North Melbourne before 31 October 1994.\n\n**What it requires**: These camshafts must be checked for proper shape, size, and heat damage (thermal cracks) caused by grinding. The inspection must follow an officially approved repair procedure (known as a CAR 35 approval).\n\n**When to comply**: \n- For camshafts currently in engines: inspect at the next engine overhaul or when the engine is stripped down for major maintenance, whichever comes first\n- For spare camshafts: inspect before installing them in any engine\n\n**Why it exists**: The repairs were done without proper regulatory approval (contrary to Civil Aviation Order 106 and another directive AD/ENG/4). However, testing by CASA's Materials Evaluation Facility found that Wades Camshafts' repair method doesn't actually damage the parts or make them unsafe. Rather than grounding aircraft immediately, this directive allows the camshafts to stay in service until the next scheduled engine access, while ensuring they get checked eventually."},"summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This summary reflects the airworthiness directive as issued, without any subsequent amendments."},"complexity_factors":["Applies only to a specific batch of repaired engine parts from one supplier","Requires technical inspection against an approved engineering procedure"],"plain_english_summary":"This CASA airworthiness directive targets Teledyne Continental piston engines with camshafts repaired by Wades Camshafts Pty Ltd before 31 Oct 1994. Owners, operators and maintenance providers must inspect affected camshafts for lobe profile/dimensions and grinding-induced thermal cracks at the next engine overhaul or bulk strip, and inspect spares before installation. Effective 2 Mar 1995, CASA found the repair method didn’t degrade safety, so immediate grounding isn’t required."}},"importantCases":[],"_links":{"self":"/api/acts/ad-con-73-unapproved-camshaft-repairs","history":"/api/acts/ad-con-73-unapproved-camshaft-repairs/history","analysis":"/api/acts/ad-con-73-unapproved-camshaft-repairs/analysis","conflicts":"/api/acts/ad-con-73-unapproved-camshaft-repairs/conflicts","importantCases":"/api/acts/ad-con-73-unapproved-camshaft-repairs/important-cases","documents":"/api/acts/ad-con-73-unapproved-camshaft-repairs/documents"}}