{"id":"F2006B02734","name":"AD/B727/33 Amdt 1 - Nose Gear Steering Metering Valve and Cylinder - Inspection and Modification","slug":"ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42076,"registerId":"commonwealth-F2006B02734-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/33 Amdt 1 - Nose Gear Steering Metering Valve and Cylinder - Inspection and 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/B727/33\n\nAmdt 1\n\n\nNose Gear Steering Metering Valve and Cylinder - Inspection and Modification\n\n\n9/67\n\n \n\nApplicability: All models.\n\n \n\nDocument: Boeing SB No. 32-88, Rev. 1. 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","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This entry is labelled \"Amdt 1,\" indicating it amends a prior AD/B727/33. The supplied text shows the amended directive applies to all Boeing 727 models and requires immediate compliance with Boeing SB No. 32-88, Rev. 1 (See: \"Amdt 1\", \"Applicability: All models.\", \"Document: Boeing SB No. 32-88, Rev. 1. Compliance: Forthwith.\"). The supplied excerpt does not include the original AD text, so the precise nature and extent of the change from the original AD cannot be determined from the material provided."},"complexity_factors":["Narrow technical focus: concerns a single aircraft system (nose gear steering metering valve and cylinder). (See: title.)","Broad applicability: applies to all Boeing 727 models, increasing the number of affected operators. (See: \"Applicability: All models.\")","Immediate compliance requirement: sets compliance as \"Forthwith,\" allowing no scheduled window and raising logistical complexity. (See: \"Compliance: Forthwith.\")","Delegation to external technical document: the AD refers to Boeing SB No. 32-88, Rev. 1 for procedural detail, so the exact tasks are contained outside the AD text. (See: \"Document: Boeing SB No. 32-88, Rev. 1.\")","Limited procedural detail in the AD itself: the AD text supplied does not state exemptions, alternative methods of compliance, timelines, or parts requirements, requiring operators to consult the SB and potentially the regulator for clarifications."],"plain_english_summary":"### What this instrument does\n\nThis is an airworthiness directive (AD) titled \"Nose Gear Steering Metering Valve and Cylinder - Inspection and Modification\" for Boeing 727 aeroplanes (AD/B727/33 Amdt 1). It requires operators to carry out the inspection and modification work described in Boeing Service Bulletin No. 32-88, Revision 1. (See: \"Document: Boeing SB No. 32-88, Rev. 1. Compliance: Forthwith.\")\n\n### Who it affects\n\n- All operators and owners of Boeing 727 series aeroplanes (See: \"Applicability: All models\").\n- Maintenance organisations and personnel who perform the inspections and modifications called for in the Boeing service bulletin.\n\n### What operators must do and when\n\n- Follow the procedures set out in Boeing SB No. 32-88, Rev. 1 for inspecting and modifying the nose gear steering metering valve and cylinder. (See: \"Document: Boeing SB No. 32-88, Rev. 1.\")\n- Comply immediately: the AD sets compliance as \"Forthwith,\" meaning the required work must be done without delay. (See: \"Compliance: Forthwith.\")\n\n### Who pays and who decides\n\n- Aircraft owners/operators pay for the inspections, any modifications, spare parts and the labour/time required to perform them. The AD places the compliance obligation on the operator (see applicability and compliance statements above).\n- The Civil Aviation Safety Authority issues the AD and enforces compliance under Part 39 of the Civil Aviation Regulations 1998 (this AD appears in the Schedule of Airworthiness Directives). The AD delegates the technical steps to the manufacturer's service bulletin (Boeing SB No. 32-88, Rev. 1).\n\n### Incentives, costs and trade-offs\n\n- Incentives: Operators are required to comply to keep the aircraft airworthy and legally able to operate. Non-compliance risks regulatory enforcement and grounding of aircraft.\n- Direct costs: time in maintenance, parts and labour to inspect and modify the nose gear steering metering valve and cylinder (the AD does not list costs; the specific tasks are in the Boeing service bulletin referenced).\n- Indirect costs/opportunity costs: aircraft downtime while work is done; potential scheduling impacts if multiple aircraft require the same work.\n\n### Implementation and compliance burden\n\n- The AD's technical instructions are contained in the referenced Boeing service bulletin; operators must obtain and follow that SB (See: \"Document: Boeing SB No. 32-88, Rev. 1.\").\n- The AD gives no implementation timetable beyond \"Forthwith,\" which concentrates pressure on operators to act immediately and may complicate planning for parts and workshop capacity.\n- The AD does not, in the supplied text, list exemptions, alternative methods of compliance (AMOCs), or time intervals; any discretion for alternative compliance would rest with the regulator or appear in additional guidance, not in the text shown.\n\n### Risks and practical effects to watch for\n\n- Dependence on availability of serviceable parts and qualified maintenance staff for timely compliance.\n- Potential short-term reduction in aircraft availability while inspections/modifications are carried out.\n- The AD references the manufacturer’s service bulletin for technical detail; operators must source that document and follow it precisely to meet the AD requirement.\n\n### Source-grounded summary statements\n\n- The legal requirement in this AD is: inspect and modify the nose gear steering metering valve and cylinder according to Boeing SB No. 32-88, Rev. 1, and do so forthwith (See: lines: \"Document: Boeing SB No. 32-88, Rev. 1. Compliance: Forthwith.\" and \"Applicability: All models\").\n- The document places the operational cost and compliance burden on aircraft operators and their maintenance providers (inferred from the AD’s applicability and compliance instructions)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is Amendment 1 to an existing Airworthiness Directive (AD/B727/33). Airworthiness Directives are inherently narrow, targeted safety instruments. The amendment appears to maintain the original scope — addressing a specific mechanical component on a specific aircraft type. There is no evidence of scope creep; the document remains tightly focused on the nose gear steering system of Boeing 727 aircraft."},"complexity_factors":["Extremely short document (approximately 150 words)","No defined terms section — relies entirely on external technical reference (Boeing SB No. 32-88, Rev. 1)","No conditional logic or nested exceptions","Single, unambiguous applicability clause ('All models')","Simple command structure: identify aircraft → reference technical document → comply immediately","Cross-reference is singular and explicit (one Boeing Service Bulletin)"],"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) that requires specific maintenance actions on aircraft.\n\n**What it does:** It orders owners and operators of **Boeing 727 series aircraft** to inspect and modify the **nose gear steering metering valve and cylinder** — a hydraulic component that controls how the front wheels steer the plane on the ground.\n\n**Why it matters:** The steering system is critical for safe taxiing, takeoff, and landing. This directive likely addresses a known defect or failure mode that could cause loss of steering control, runway excursions, or other safety hazards.\n\n**Who must comply:** Anyone operating a Boeing 727 in Australia (all models are covered). \n\n**What must be done:** Follow the instructions in **Boeing Service Bulletin 32-88, Revision 1** — a technical document from the manufacturer detailing the inspection and modification procedures. \n\n**When:** **Forthwith** — meaning immediately, without delay. This indicates an urgent safety issue."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification","history":"/api/acts/ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification/history","analysis":"/api/acts/ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification/analysis","conflicts":"/api/acts/ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification/important-cases","documents":"/api/acts/ad-b727-33-amdt-1-nose-gear-steering-metering-valve-and-cylinder-inspection-and-modification/documents"}}