{"id":"F2006B05488","name":"AD/PA-23/61 Amdt 2 - Flap Outboard Hinges - Inspection and Replacement","slug":"ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46312,"registerId":"commonwealth-F2006B05488-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-23/61 Amdt 2 - Flap Outboard Hinges - Inspection and Replacement","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nPiper PA-23 (Apache and Aztec) Series Aeroplanes\n\nAD/PA-23/61\n\nAmdt 2\n\n  \n\nFlap Outboard Hinges \\- Inspection and Replacement\n\n  \n7/75\n\nApplicability: All model PA-23-250 with S/Nos. 27-3050, 27-3154 to 27-7405330.\n\nRequirement: 1. With the flaps in the full down position inspect the flap outboard hinges for cracks with the aid of a 10 power magnify- ing glass and for clearance between the outboard flap hinge and the aileron and flap hinge bracket assembly.\n\nNote: This inspection shall be performed on all referenced aeroplanes including those which have had the hinges replaced in accordance with Piper SB No. 408A.\n\n2. Replace the flap outboard hinge in accordance with Piper SB No. 408B.\n\nCompliance: For para. 1 - Within 100 hours time in service after 31 July 1975 and thereafter at intervals not exceeding 100 hours time in service until replaced in accordance with Piper SB No. 408B.\n\nFor para. 2 \\- At the next Major Inspection after 30 September 1975.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, targeted safety directive focused on a specific mechanical defect in specific aircraft. It has not expanded beyond its original purpose of addressing flap hinge integrity in Piper PA-23-250 aircraft."},"complexity_factors":["Very short document (under 300 words)","Only 2 substantive requirements (inspection and replacement)","Single applicability criterion (specific aircraft model and serial numbers)","Clear compliance deadlines with specific dates and flight hour intervals","No defined terms section, no cross-references to other legislation beyond manufacturer service bulletins","Simple conditional structure: 'inspect until you replace'"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to specific **Piper PA-23 Apache and Aztec aircraft** (certain serial numbers of the PA-23-250 model).\n\n**What it requires:**\n- **Inspection:** Owners/operators must check the outboard flap hinges for cracks using a 10x magnifying glass, and check for proper clearance between the hinge and nearby parts. This must happen every 100 flight hours.\n- **Replacement:** Eventually, the hinges must be replaced following Piper's Service Bulletin 408B (an official repair instruction from the manufacturer).\n\n**Why it matters:**\nFlap hinges are critical structural components. If they crack or fail, the flaps (which control lift and descent) could malfunction or detach during flight. This directive prevents potential accidents by catching fatigue damage early and mandating permanent fixes.\n\n**Who must comply:**\nAnyone operating the affected aircraft — including those who already replaced hinges under an earlier service bulletin (SB 408A), because this directive requires the newer SB 408B standard."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This instrument is titled 'Amdt 2' to AD/PA-23/61 and sets mandatory inspection and replacement requirements for listed PA-23-250 serial numbers. It prescribes recurring 100‑hour inspections until replacement and a replacement deadline at the next Major Inspection after 30 September 1975. The label 'Amdt 2' indicates it alters the prior AD; the original AD text is not provided here for a line‑by‑line comparison."},"complexity_factors":["Narrow applicability limited to PA-23-250 with specified serial numbers (Applicability).","Detailed inspection procedure: flaps full down, use 10× magnifying glass, check clearance to hinge bracket/aileron (Requirement para. 1).","Affirms inspections apply even if hinge was previously replaced per Piper SB No. 408A (Requirement note).","Mandatory replacement must follow Piper SB No. 408B (Requirement para. 2).","Mixed timing regime: recurring 100‑hour inspections until replacement and a hard replacement deadline at the next Major Inspection after 30 Sept 1975 (Compliance paras 1–2).","Compliance dates anchored to 31 July 1975 and 30 September 1975, creating immediate time-bound obligations (Compliance).","Compliance and cost burdens fall on aircraft owners/operators who must perform/arrange inspections and replacements (Requirement & Compliance)."],"plain_english_summary":"Requires owners/operators of specific Piper PA-23-250 aircraft (listed serial numbers) to inspect the flap outboard hinges for cracks (using a 10× magnifying glass) and for clearance, and to replace the hinge per Piper SB No. 408B. Inspections must occur within 100 flight hours after 31 July 1975 and every 100 hours until replacement; replacement is due at the next Major Inspection after 30 September 1975. This creates recurring inspection and a mandated replacement cost for affected aircraft."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement","history":"/api/acts/ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement/history","analysis":"/api/acts/ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement/important-cases","documents":"/api/acts/ad-pa-23-61-amdt-2-flap-outboard-hinges-inspection-and-replacement/documents"}}