{"id":"F2006B05744","name":"AD/PA-31/4 Amdt 1 - Elevator Torque Tube - Inspection","slug":"ad-pa-31-4-amdt-1-elevator-torque-tube-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":135573,"registerId":"commonwealth-F2006B05744-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-31/4 Amdt 1 - Elevator Torque Tube - 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-31 Series Aeroplanes\n\n \n\nAD/PA-31/4\n\nAmdt 1\n\n\nElevator Torque Tube - Inspection 12/68\n\n \n\nApplicability: All models not modified in accordance with Section 11 of Piper SB No. 284.\n\n \n\nRequirement: Remove the elevator torque tube assembly from the aircraft and dismantle the horn assembly P/N 40006-00 and brackets P/N 40066-00 from the tube. Remove the finish from the tube and inspect for cracking using dye penetrant or magnetic particle methods.\n\n \n\nCompliance: At intervals not exceeding 100 hours time in service.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive focused on a specific mechanical inspection. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined terms implicitly used ('time in service' and part numbers)","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Single, straightforward compliance requirement with clear interval","No conditional logic, exceptions, or nested provisions","Simple applicability test (modified vs unmodified aircraft)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to **Piper PA-31 series aircraft** (a type of twin-engine plane).\n\n**What it requires:**\nOwners and operators must **inspect the elevator torque tube** — a critical component that helps control the plane's pitch (up and down movement). Specifically, they must:\n- Remove the torque tube assembly from the aircraft\n- Take apart the horn assembly and brackets attached to it\n- Strip off any paint or coating\n- Check for cracks using **dye penetrant** (a chemical that seeps into cracks to make them visible) or **magnetic particle testing** (using magnetic fields and iron particles to detect surface flaws)\n\n**Who must comply:**\nAnyone operating a Piper PA-31 that **hasn't been modified** according to Piper Service Bulletin No. 284, Section 11.\n\n**How often:**\nEvery **100 hours of flight time** (\"time in service\" means actual flying hours, not calendar time).\n\n**Why it matters:**\nCracks in the elevator torque tube could cause **loss of pitch control**, potentially leading to a crash. This directive forces regular inspections to catch problems before they become catastrophic."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The document is labeled 'Amdt 1', indicating it amends a prior airworthiness directive. The supplied text sets out current applicability, requirement and compliance interval but does not include the pre‑amendment text or a comparison showing what was changed. From the supplied instrument alone, the nature and extent of the amendment cannot be determined."},"complexity_factors":["Technical non‑destructive testing methods required (dye penetrant or magnetic particle) increase operational complexity","Mandatory physical removal and dismantling of assemblies (elevator torque tube, horn assembly, brackets) requires maintenance facilities or contracted labour","Applicability carve‑out tied to a specific modification (Section 11 of Piper SB No. 284) requires operators to check modification status","Fixed recurrent interval (every 100 hours TIS) imposes scheduling and downtime considerations","Reference to specific part numbers (P/N 40006-00 and P/N 40066-00) requires accurate parts identification during maintenance"],"plain_english_summary":"This AD applies to Piper PA‑31 series aeroplanes (unless modified per Section 11 of Piper SB No. 284) and mandates removal of the elevator torque tube, dismantling of the horn/brackets, stripping the finish and non‑destructive inspection (dye penetrant or magnetic particle) for cracking at intervals not exceeding 100 hours TIS. It affects owners/operators who bear costs, downtime and must have NDT capability; it’s intended to detect torque‑tube cracking and preserve safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-31-4-amdt-1-elevator-torque-tube-inspection","history":"/api/acts/ad-pa-31-4-amdt-1-elevator-torque-tube-inspection/history","analysis":"/api/acts/ad-pa-31-4-amdt-1-elevator-torque-tube-inspection/analysis","conflicts":"/api/acts/ad-pa-31-4-amdt-1-elevator-torque-tube-inspection/conflicts","importantCases":"/api/acts/ad-pa-31-4-amdt-1-elevator-torque-tube-inspection/important-cases","documents":"/api/acts/ad-pa-31-4-amdt-1-elevator-torque-tube-inspection/documents"}}