{"id":"F2006B04233","name":"AD/BEECH 90/42 Amdt 1 - Fuselage Rear Bulkhead - Inspection","slug":"ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43995,"registerId":"commonwealth-F2006B04233-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 90/42 Amdt 1 - Fuselage Rear Bulkhead - 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)  Beechcraft 90 and 65-90 (King Air) Series Aeroplanes\n\n \n\nAD/BEECH 90/42\n\nAmdt 1\n\n\nFuselage Rear Bulkhead - Inspection 4/78\n\n \n\nApplicability: All models 65-90, 65-A90, B90 and C90 with S/Nos. LJ-1 to LJ-711, and E90 with S/Nos. LW-1 thru LW-212.\n\n \n\nDocument: Beechcraft SI No. 0755-103, Rev. 1.\n\n \n\nCompliance:  Within 100 hours’ time in service after achieving 500 hours’ time in service and thereafter at intervals not exceeding 600 hours’ time in service until modified in accordance with SI No. 0755-103 Rev. 1.\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 an amendment (Amdt 1) to an existing Airworthiness Directive, but the scope remains tightly focused on the original purpose: inspecting the rear bulkhead of specific Beechcraft King Air models. The amendment appears to update reference documentation or compliance details without expanding the aircraft coverage or safety objective beyond the original fuselage bulkhead inspection requirement."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 4 defined elements: applicability (aircraft models/serial numbers), reference document, compliance timing, and termination condition","No cross-references to other legislation or regulations beyond the enabling Civil Aviation Regulations 1998","Simple conditional logic: single trigger point (500 hours TIS) → initial action → recurring interval → termination condition","No nested exceptions or layered definitions","Single-purpose instrument with one clear safety objective"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nIt requires owners and operators of certain **Beechcraft King Air aeroplanes** (models 65-90, 65-A90, B90, C90, and E90 with specific serial numbers) to **inspect the rear bulkhead of the fuselage** (the structural wall at the back of the passenger cabin).\n\n**Who it affects:**\n- Owners and operators of approximately 900+ specific Beechcraft King Air aircraft (serial numbers LJ-1 through LJ-711, and LW-1 through LW-212)\n- Maintenance organisations servicing these aircraft\n\n**What must be done:**\n- **First inspection:** Within 100 hours of flying time after the aircraft reaches 500 total hours of flying time\n- **Repeat inspections:** Every 600 hours of flying time thereafter\n- **Stopping the inspections:** Only after the aircraft is modified according to Beechcraft Service Instruction No. 0755-103 Rev. 1\n\n**Why it matters:**\nThis directive addresses a potential **structural failure risk** in the rear bulkhead. Without inspection, cracks or damage could go undetected, potentially leading to **loss of cabin pressure** or **structural failure** in flight. The directive ensures safety-critical maintenance is performed on schedule."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The instrument is titled as Amendment 1 to AD/BEECH 90/42, so it modifies the existing directive. The provided text sets an inspection schedule and ties termination of inspections to completion of the modification per Beechcraft Service Instruction No. 0755-103 Rev. 1 (Document; Compliance). The exact differences from the original AD are not contained in the supplied text, so the specific textual changes from the prior version cannot be identified from this document alone."},"complexity_factors":["Targeted applicability by specific models and serial-number ranges (Applicability)","A phased compliance trigger (first inspection required within 100 hours after reaching 500 hours TIS) combined with a repeating interval (every 600 hours) (Compliance)","Termination of repeated inspections only after completing a modification specified in an external document (Document; Compliance)","Dependence on a separate manufacturer Service Instruction (SI No. 0755-103 Rev. 1) for technical procedures (Document)","Limited text provided (AD is an amendment and the full historical context or the prior AD text is not included), making comparative assessment harder (AD/BEECH 90/42 Amdt 1)"],"plain_english_summary":"This AD mandates repeated inspections of the fuselage rear bulkhead on specified Beechcraft 65‑90/90‑series serials, performed per Beechcraft Service Instruction No. 0755‑103 Rev. 1, until the cited modification is done. Owners/operators pay for inspections and the one‑time terminating modification; maintenance organisations perform the work. It matters because operators must choose between ongoing inspection costs/downtime and a single modification expense that removes the recurring inspection burden."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection","history":"/api/acts/ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection/history","analysis":"/api/acts/ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection/analysis","conflicts":"/api/acts/ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection/conflicts","importantCases":"/api/acts/ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection/important-cases","documents":"/api/acts/ad-beech-90-42-amdt-1-fuselage-rear-bulkhead-inspection/documents"}}