{"id":"F2006B10503","name":"AD/HS 125/63 - Main Landing Gear Retraction Jack Cylinder Head Attachment Lugs - Inspection, Replacement","slug":"ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116269,"registerId":"commonwealth-F2006B10503-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HS 125/63 - Main Landing Gear Retraction Jack Cylinder Head Attachment Lugs - Inspection, Replacement","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)  British Aerospace BAe 125 Series Aeroplanes\n\n \n\nAD/HS 125/63 Main Landing Gear Retraction Jack Cylinder Head\n\nAttachment Lugs - Inspection, Replacement Applicability: All models HS/DH/BH 125 series aircraft up to and including series 700. Document:               British Aerospace 125 SB 32-A197.\n\nCompliance: Before 31 October 1983.\n\n \n\nBackground: The manufacturer advises an inspection of MLG retraction jack cylinder head attachment lugs after reports of in-service cracking.\n\n\n11/83\n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete Airworthiness Directive with a single, specific purpose: addressing a known cracking defect in a particular aircraft component. It has not expanded beyond its original scope; ADs are inherently narrow, time-bound safety instruments."},"complexity_factors":["Single, specific technical requirement (one inspection/replacement task)","No defined terms section — all terminology is standard aviation engineering language","No cross-referencing to other legislation beyond the parent Civil Aviation Regulations 1988","No conditional logic or exceptions — straightforward applicability (all models up to series 700)","Extremely short document (approximately 100 words of substantive content)","Single compliance date with no alternative methods or phased implementation"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\n- Requires owners and operators of British Aerospace BAe 125 series aeroplanes (including HS, DH, and BH 125 models up to series 700) to inspect the **main landing gear retraction jack cylinder head attachment lugs** — essentially, critical metal brackets that connect the hydraulic jack (which raises and lowers the main wheels) to the aircraft structure.\n- If cracks are found, the damaged parts must be replaced.\n\n**Why it matters:**\n- The manufacturer reported **in-service cracking** — meaning these parts were cracking while planes were actually flying. If an attachment lug fails, the main landing gear might not retract or extend properly, or could collapse entirely. This creates serious safety risks during takeoff and landing.\n\n**Who must comply:**\n- Anyone operating the affected aircraft models (all BAe 125 series up to and including series 700).\n- **Deadline:** Before 31 October 1983.\n\n**How to comply:**\n- Follow the manufacturer's Service Bulletin 32-A197 (a technical instruction document from British Aerospace).\n\nThis is a **one-off mandatory inspection** — not ongoing legislation, but a specific safety fix for a known mechanical defect."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's stated scope is an inspection and replacement requirement for MLG retraction jack cylinder head attachment lugs on specified BAe 125 series aircraft, prompted by reported in-service cracking. The instrument text does not indicate any change to that original intent; it sets a single compliance action, cites the manufacturer's service bulletin for procedure, identifies the affected models, and gives a compliance deadline. (See: \"Applicability\", \"Document\", \"Compliance\", \"Background\".)"},"complexity_factors":["Single discrete technical action required (inspection and replacement of a specific component). (See: \"Main Landing Gear Retraction Jack Cylinder Head Attachment Lugs - Inspection, Replacement\")","Fixed compliance deadline (before 31 October 1983) reduces ongoing regulatory ambiguity. (See: \"Compliance: Before 31 October 1983.\")","Reliance on a single manufacturer service bulletin for procedures (British Aerospace 125 SB 32-A197) concentrates procedural detail outside the AD. (See: \"Document: British Aerospace 125 SB 32-A197.\")","Technical execution requires certified maintenance capability and possible part availability, adding operational complexity despite straightforward mandate. (Implied by inspection/replacement requirement.)","Applicability limited to a defined set of aircraft models, reducing scope but requiring fleet identification by operators. (See: \"Applicability: All models HS/DH/BH 125 series aircraft up to and including series 700.\")"],"plain_english_summary":"What this instrument does\n\n- This is an Airworthiness Directive (AD) issued under the Civil Aviation Safety Authority's Part 39 schedule of airworthiness directives. It requires operators of certain British Aerospace 125 series aeroplanes to inspect the attachment lugs on the main landing gear (MLG) retraction jack cylinder heads and to replace them where required. (See: \"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105\" and \"AD/HS 125/63\".)\n\nWho is affected\n\n- All operators and owners of HS/DH/BH 125 series aircraft up to and including series 700 are in scope. (See: \"Applicability: All models HS/DH/BH 125 series aircraft up to and including series 700.\")\n\nWhat you must do, mechanically\n\n- Carry out the inspection and any required replacement in accordance with the manufacturer's service bulletin: British Aerospace 125 SB 32-A197. (See: \"Document: British Aerospace 125 SB 32-A197.\")\n- Complete the required work before the specified compliance date: before 31 October 1983. (See: \"Compliance: Before 31 October 1983.\")\n\nWhy the directive was issued (source statement)\n\n- The manufacturer's advice is the stated reason: there were reports of in-service cracking of the MLG retraction jack cylinder head attachment lugs, and the manufacturer advised inspection. (See: \"Background: The manufacturer advises an inspection of MLG retraction jack cylinder head attachment lugs after reports of in-service cracking.\")\n\nPractical effects, who pays, and incentives\n\n- Who pays: Aircraft owners/operators pay for the inspection, any corrective replacements, parts, and associated maintenance labour and downtime. (Implied by the requirement that operators comply with the AD; see \"Applicability\" and \"Document\".)\n- Who decides: The Civil Aviation Safety Authority issued the AD under Part 39; the manufacturer produced the service bulletin that specifies the inspection/replacement procedure. Operators must follow the manufacturer's document to meet the AD. (See: header and \"Document: British Aerospace 125 SB 32-A197.\")\n- Behaviour changes: Operators must schedule and perform the inspection prior to the compliance date and arrange replacements where faults are found. This may change maintenance scheduling, resource allocation, and aircraft availability.\n\nCosts, trade-offs and risks to note (based on the instrument's mechanics)\n\n- Direct costs: Inspection labour and potential replacement part and installation costs, plus aircraft downtime while maintenance is performed. (Implied by mandatory inspection/replacement requirement and reliance on a manufacturer service bulletin.)\n- Incentives: Operators have an incentive to inspect promptly before the compliance date to avoid regulatory non-compliance and to detect cracking early. Early replacement can avoid in-service failure but increases near-term maintenance spend.\n- Implementation risks: The AD depends on operators following the manufacturer’s SB; incomplete compliance or incorrect execution of the SB could leave the safety issue unresolved. Compliance requires access to the parts and maintenance capability specified in the service bulletin. (See: \"Document: British Aerospace 125 SB 32-A197.\")\n- Compliance burden: Administrative and operational burden falls on operators to plan, execute and record the inspection and any replacements before the deadline. (See: \"Compliance: Before 31 October 1983.\")\n\nScope and limits\n\n- The AD applies only to HS/DH/BH 125 series aircraft up to and including series 700. It does not extend to later series or other models unless separately specified. (See: \"Applicability.\")\n\nSource citations\n\n- Applicability, Document, Compliance and Background are taken directly from the text of AD/HS 125/63 and its header in the Schedule of Airworthiness Directives."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement","history":"/api/acts/ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement/history","analysis":"/api/acts/ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement/analysis","conflicts":"/api/acts/ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement/conflicts","importantCases":"/api/acts/ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement/important-cases","documents":"/api/acts/ad-hs-125-63-main-landing-gear-retraction-jack-cylinder-head-attachment-lugs-inspection-replacement/documents"}}