{"id":"F2006B11109","name":"AD/LEARJET 35/3 - Lower Cabin Door Jambs - Inspection","slug":"ad-learjet-35-3-lower-cabin-door-jambs-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56770,"registerId":"commonwealth-F2006B11109-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/LEARJET 35/3 - Lower Cabin Door Jambs - 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)  Gates Learjet 35 and 36 Series Aeroplanes\n\n \n\nAD/LEARJET 35/3 Lower Cabin Door Jambs - Inspection 4/76\n\nApplicability: All model 35 with S/Nos. 35-001 to 35-035. And all model 36 with S/Nos. 36-001 to 36-016 with the 24 inch cabin door.\n\n \n\nDocument: Gates Learjet SB 35/36-52-1.\n\n \n\nCompliance: Within 75 hours time in service after 30 April 1976.\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":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The supplied AD sets a specific, narrow scope (listed serial-number ranges of Learjet 35 and 36 with the 24 inch door) and a single compliance requirement (inspection within 75 hours after 30 April 1976). The text supplied contains no indication that the scope has changed from an earlier version; it presents a standalone requirement directed to those specific aircraft. (\"Applicability\"; \"Compliance\")"},"complexity_factors":["Narrow applicability limited to specific serial-number ranges (models 35: S/N 35-001 to 35-035; model 36: S/N 36-001 to 36-016 with 24 inch door) (\"Applicability\")","Single required action: an inspection of the lower cabin door jambs, not a multi-step regulatory programme (AD title and content)","Short, fixed compliance window: must be done within 75 hours time in service after 30 April 1976, which imposes near-term scheduling but is straightforward to interpret (\"Compliance\")","Reference to an external technical document (Gates Learjet SB 35/36-52-1) means compliance depends on obtaining and following that service bulletin rather than reading all steps in the AD (\"Document\")","The AD text supplied does not set out corrective actions, acceptance criteria, or follow-up intervals, creating potential ambiguity about post-inspection steps unless the service bulletin specifies them (absence of such details in the supplied AD)","Regulatory provenance under Part 39 creates an enforcement context, but the AD itself is operationally concise (header: \"Civil Aviation Regulations 1998, PART 39\")"],"plain_english_summary":"What this instrument does (mechanically)\n\n- It is an airworthiness directive (AD) issued under the Commonwealth Civil Aviation Regulations, Part 39 (Schedule of Airworthiness Directives) that requires a one-off inspection of the lower cabin door jambs on certain Gates Learjet 35 and 36 aeroplanes. (Header; \"SCHEDULE OF AIRWORTHINESS DIRECTIVES\"; \"AD/LEARJET 35/3 Lower Cabin Door Jambs - Inspection\")\n- The inspection applies only to: all model 35 aircraft with serial numbers 35-001 to 35-035, and all model 36 aircraft with serial numbers 36-001 to 36-016 fitted with the 24 inch cabin door. (\"Applicability\")\n- Compliance is mandatory within 75 hours time in service after 30 April 1976. (\"Compliance: Within 75 hours time in service after 30 April 1976\")\n- The AD directs operators to the Gates Learjet service bulletin SB 35/36-52-1 for the inspection procedure. (\"Document: Gates Learjet SB 35/36-52-1\")\n\nWho this affects and who pays\n\n- The people who must act are the operators or owners of the specified Learjet 35 and 36 aircraft (those within the listed serial-number ranges). (\"Applicability\")\n- Those operators bear the direct cost and labour of arranging and performing the inspection within the stated time window. (\"Compliance\")\n- The service bulletin named in the AD supplies the technical steps to be followed; whoever carries out the inspection (the operator or a maintenance provider they hire) will follow that document. (\"Document\")\n\nWhy it matters (stated and implied purpose)\n\n- The instrument is an airworthiness directive: by form and placement it is intended to address an identified airworthiness issue through mandatory inspection. (Header: \"SCHEDULE OF AIRWORTHINESS DIRECTIVES\" and the title of the AD)\n- The AD achieves that by imposing a mandatory inspection requirement on a defined set of aircraft within a fixed time window, and by referring to a manufacturer service bulletin for the technical procedure. (\"Applicability\"; \"Compliance\"; \"Document\")\n\nPractical mechanics, incentives and constraints\n\n- Timing rule: operators must complete the inspection within 75 hours time in service after 30 April 1976. That creates a near-term operational constraint on each affected aircraft: the inspection must be scheduled into service hours within the window. (\"Compliance\")\n- Procedural rule: the AD points to Gates Learjet SB 35/36-52-1 for the inspection method. Operators must obtain and follow that external document to comply. (\"Document\")\n- Who decides and enforces: the AD is issued under the Commonwealth Civil Aviation Regulations, Part 39 framework; enforcement and oversight follow the regulatory regime for airworthiness directives. (Header: \"Civil Aviation Regulations 1998, PART 39\")\n\nCosts, burdens, and implementation risks (as can be seen in the text)\n\n- Direct compliance cost is the labour and any parts or follow-up work needed after the inspection; the AD text itself does not state those costs or what corrective actions (if any) are required when defects are found. (The AD references the service bulletin but the AD text provided does not list corrective steps.) (\"Document\"; absence of corrective-action text in the supplied AD)\n- Administrative burden includes locating and following the referenced service bulletin and documenting compliance within maintenance records. (\"Document\"; \"Compliance\")\n- Operational impact is that aircraft may need to be scheduled out of service (or have maintenance resources diverted) to meet the 75-hour window. (\"Compliance\")\n\nTrade-offs and substitution effects visible from the instrument\n\n- The AD concentrates obligations on a defined subset of aircraft (specific serial-number ranges). That concentrates the compliance cost on those owners/operators while leaving others unaffected. (\"Applicability\")\n- The AD requires following a manufacturer service bulletin rather than specifying the inspection steps in full within the AD text; this substitutes reliance on external technical guidance for prescriptive regulatory text. (\"Document\")\n\nWhat the AD does not specify in this text\n\n- The supplied AD does not include the inspection procedure details (it references the service bulletin) nor does it spell out thresholds for corrective action or repeat inspection intervals in this text. (\"Document\"; the AD text as supplied)\n\nBottom line (mechanical effect)\n\n- Operators of the listed Gates Learjet 35/36 aircraft must have the lower cabin door jambs inspected in accordance with Gates Learjet SB 35/36-52-1 within 75 hours time in service after 30 April 1976. The operator pays for and arranges the inspection; the AD is enforced under Part 39 of the Civil Aviation Regulations. (\"Applicability\"; \"Document\"; \"Compliance\"; header)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused specifically on door jamb inspections for early-production Learjet 35/36 aircraft. It has not expanded beyond its original technical scope."},"complexity_factors":["Extremely short document (under 200 words)","Only 4 operative provisions: applicability, reference document, compliance deadline, and action required","No defined terms section — all language is ordinary technical aviation terminology","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Simple conditional logic: serial number ranges AND door size (for Model 36 only)","Single compliance trigger (calendar date + flight hours)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific Gates Learjet 35 and 36 series aircraft to inspect the lower cabin door jambs (the structural frames around the bottom of the passenger door) for defects.\n\n**Who it affects:**\n- Owners and operators of Learjet Model 35 aircraft with serial numbers 35-001 through 35-035\n- Owners and operators of Learjet Model 36 aircraft with serial numbers 36-001 through 36-016, but **only** those fitted with the 24-inch cabin door\n\n**What must be done:**\n- Inspect the lower cabin door jambs following the procedures in Gates Learjet Service Bulletin 35/36-52-1\n- Complete this inspection within 75 hours of flight time after 30 April 1976\n\n**Why it matters:**\nDoor jambs are critical structural components. If they crack or fail, it could lead to rapid decompression at altitude or door separation in flight — a serious safety risk. This AD ensures potential defects are caught before they cause an accident."}},"importantCases":[],"_links":{"self":"/api/acts/ad-learjet-35-3-lower-cabin-door-jambs-inspection","history":"/api/acts/ad-learjet-35-3-lower-cabin-door-jambs-inspection/history","analysis":"/api/acts/ad-learjet-35-3-lower-cabin-door-jambs-inspection/analysis","conflicts":"/api/acts/ad-learjet-35-3-lower-cabin-door-jambs-inspection/conflicts","importantCases":"/api/acts/ad-learjet-35-3-lower-cabin-door-jambs-inspection/important-cases","documents":"/api/acts/ad-learjet-35-3-lower-cabin-door-jambs-inspection/documents"}}