{"id":"F2006B02719","name":"AD/B727/2 - Landing Gear Warning System - Modification","slug":"ad-b727-2-landing-gear-warning-system-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42035,"registerId":"commonwealth-F2006B02719-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/2 - Landing Gear Warning System - Modification","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)  Boeing 727 Series Aeroplanes\n\n \n\nAD/B727/2 Landing Gear Warning System - Modification 3/65\n\nApplicability: All models. Document: Boeing SB 31-6. Compliance: Forthwith.\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\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 discrete, single-issue safety directive from 1965 addressing a specific technical modification to the landing gear warning system. There is no evidence of scope creep; it remains tightly focused on its original purpose of mandating a manufacturer-recommended safety fix."},"complexity_factors":["Extremely short document — only 4 substantive lines of regulatory text","No defined terms section — relies on external technical reference (Boeing SB 31-6)","No conditional logic or exceptions — blanket applicability to all models","Single compliance requirement with immediate effect ('Forthwith')","No cross-references to other legislation beyond the enabling Civil Aviation Regulations 1998","Standardised AD format with minimal prose"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) for **Boeing 727 aircraft**.\n\n**What it does:**\n- Requires owners and operators of all Boeing 727 models to modify the **landing gear warning system** — the system that alerts pilots if the landing gear isn't properly deployed for landing.\n- The modification must follow **Boeing Service Bulletin 31-6** (a technical instruction document from the manufacturer).\n\n**Who it affects:**\n- Anyone who owns or operates a Boeing 727 series aircraft in Australia.\n\n**Why it matters:**\n- Landing gear failures or pilot oversights can lead to dangerous \"belly landings\" where the plane lands without wheels down. This directive fixes a known safety issue with the warning system to prevent accidents.\n- The word **\"Forthwith\"** means the modification must be done **immediately** — there's no grace period because the safety risk is considered urgent.\n\n**Key details:**\n- **AD/B727/2** — this is the second Airworthiness Directive for the Boeing 727\n- **3/65** — issued in March 1965 (showing this is a historical directive from the early jet age)\n- Applies to **all models** of the Boeing 727 (the 727-100, 727-200, etc.)"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive applies to all Boeing 727 models and specifies immediate compliance while delegating technical steps to Boeing SB 31-6 (AD/B727/2; Applicability: All models; Document: Boeing SB 31-6; Compliance: Forthwith). The provided text contains no indication that the AD changes scope from an earlier intent; it sets a universal requirement for the fleet covered by the AD."},"complexity_factors":["Immediate compliance required (\"Forthwith\") increases operational and scheduling complexity for operators.","Technical instructions are delegated to an external document (Boeing SB 31-6), so the AD itself lacks procedural detail and relies on another source for implementation.","Wide scope: applies to all Boeing 727 models, meaning many operators and individual aircraft are affected (Applicability: All models).","Potential supply-chain and maintenance-capacity constraints for parts or qualified technicians needed to perform the modification.","Regulatory enforcement and record-keeping obligations create administrative compliance tasks for operators and maintenance providers.","Possible need for approved alternatives or exemptions requires interaction with the regulator, adding procedural complexity if operators cannot immediately comply."],"plain_english_summary":"This Airworthiness Directive (AD/B727/2) mandates an immediate modification to the Boeing 727 landing‑gear warning system, requiring operators to implement Boeing Service Bulletin 31‑6 forthwith. It applies to all 727 models, obliges owners/operators and maintenance organisations to carry out and record the work, and places costs and operational disruption on operators while the regulator enforces compliance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-2-landing-gear-warning-system-modification","history":"/api/acts/ad-b727-2-landing-gear-warning-system-modification/history","analysis":"/api/acts/ad-b727-2-landing-gear-warning-system-modification/analysis","conflicts":"/api/acts/ad-b727-2-landing-gear-warning-system-modification/conflicts","importantCases":"/api/acts/ad-b727-2-landing-gear-warning-system-modification/important-cases","documents":"/api/acts/ad-b727-2-landing-gear-warning-system-modification/documents"}}