{"id":"F2006B05509","name":"AD/PA-23/82 - Flap Spar Hinge Attachment Areas - Inspection","slug":"ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46364,"registerId":"commonwealth-F2006B05509-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-23/82 - Flap Spar Hinge Attachment Areas - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Piper PA-23 (Apache and Aztec) Series Aeroplanes\n\n \n\nAD/PA-23/82 Flap Spar Hinge Attachment Areas - Inspection 4/81\n\nApplicability: All models PA-23/PA23-160, PA23-235, PA-23-250 and PA-23-250 (6 place) with S/Nos. prior to 27-7405301.\n\n \n\nDocument: Piper SL No. 853.\n\n \n\nNote: FAA AD 81-04-05 amendment 39-4040 also refers.\n\n \n\nCompliance:  Unless already accomplished, initially inspect within 100 hours time in service after achieving 2000 hours time in service since manufacture and thereafter at intervals not exceeding 100 hours time in service until modified in accordance with Piper SL 853.\n\n \n\nBackground: Reports have been received by the manufacturer of cracks forming in the flap spar and radiating from the hinge attachment areas.\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Based on the supplied text, the AD sets out inspection and modification obligations for a defined set of PA-23 models and serial numbers to address reported cracking in flap spar hinge attachment areas (Applicability; Compliance; Background). The instrument does not indicate any expansion or narrowing of that scope beyond the specified models, serial-number cutoff, inspection intervals, and the terminating modification in Piper SL No. 853."},"complexity_factors":["Conditional timing: initial inspection triggered by reaching 2,000 hours TIS and then within 100 hours thereafter (Compliance).","Recurring interval requirement: inspections every 100 hours until modification (Compliance).","Narrow applicability by model and serial-number cutoff (Applicability).","Dependency on an external service document (Piper SL No. 853) for the modification that ends the inspection requirement (Document).","Cross-reference to a parallel FAA airworthiness directive (Note) which may require operators to consult multiple documents (Note)."],"plain_english_summary":"This AD requires owners/operators of specified Piper PA‑23 (Apache/Aztec) aeroplanes (serials before 27‑7405301) to inspect the flap spar hinge attachment areas for cracking: an initial check within 100 hours TIS after the aeroplane reaches 2,000 hours TIS, then every 100 hours thereafter until the aircraft is modified per Piper Service Letter No. 853.  \n\nIt matters because reported cracks could compromise safety; operators must schedule recurring inspections, bear costs for inspections/repairs, and carry out the SL‑853 modification to end the recurring inspections."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific safety-of-flight issue with a particular aircraft type. It has not expanded beyond its original purpose of mandating inspections for flap spar cracks in affected Piper PA-23 aircraft."},"complexity_factors":["Single, specific mechanical issue (flap spar cracks)","Clear applicability criteria (specific aircraft models and serial number cutoff)","Simple compliance timeline (100 hours after 2000 hours, then every 100 hours)","Only one cross-reference (to FAA AD 81-04-05 for additional context)","No defined terms section","No nested exceptions or conditional logic","Short document (approximately 150 words of substantive content)"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it like a compulsory recall notice, but for aircraft instead of cars.\n\n**What it does:** It requires owners and operators of specific Piper PA-23 Apache and Aztec aeroplanes to inspect the flap spar hinge attachment areas for cracks.\n\n**Who it affects:** Owners and operators of Piper PA-23 series aircraft with serial numbers before 27-7405301. This includes models PA-23-160, PA-23-235, PA-23-250, and the 6-seat PA-23-250 variant.\n\n**What must be done:**\n- **When to start:** Once the aircraft reaches 2,000 flight hours since manufacture, an inspection must be done within the next 100 flight hours.\n- **How often:** Every 100 flight hours thereafter.\n- **When it stops:** Once the aircraft is modified according to Piper Service Letter No. 853.\n\n**Why it matters:** Cracks have been found in the flap spar (a structural beam that supports the flaps — the moving parts on the wing that help with lift during takeoff and landing). These cracks start at the hinge attachment points and can spread. If left unchecked, this could lead to structural failure of the flap system, potentially causing loss of control during critical phases of flight.\n\n**Key point:** This is not optional. Compliance is mandatory under the Civil Aviation Regulations 1998."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection","history":"/api/acts/ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection/history","analysis":"/api/acts/ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection/analysis","conflicts":"/api/acts/ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection/conflicts","importantCases":"/api/acts/ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection/important-cases","documents":"/api/acts/ad-pa-23-82-flap-spar-hinge-attachment-areas-inspection/documents"}}