{"id":"F2006B03157","name":"AD/B747/26 - Descent Device Handle Strap - Inspection and Replacement","slug":"ad-b747-26-descent-device-handle-strap-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42529,"registerId":"commonwealth-F2006B03157-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/26 - Descent Device Handle Strap - Inspection and 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)  Boeing 747 Series Aeroplanes\n\n \n\n# AD/B747/26 Descent Device Handle Strap - Inspection\n\nand Replacement\n\nApplicability: All models 747 with line numbers 1 to 467. Document:  1. Boeing Alert SB No. 747-25-A2551; and\n\n2. Frost Engineering SB No. 379103-25-002. Compliance: Before 1 March 1981.\n\n# 2/81\n\nBackground: On overseas aeroplanes several descent devices were found with one or both handle straps broken.\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, time-bound safety directive focused on a specific mechanical defect in specific aircraft. It has not expanded beyond its original purpose of ensuring descent device handle strap integrity."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined references (the service bulletins)","Single, unambiguous applicability clause (line numbers 1-467)","One clear compliance deadline with no conditional exceptions","No cross-references to other legislation or regulations beyond the enabling Civil Aviation Regulations 1998","Simple imperative structure: inspect and replace by a fixed date"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nRequires owners and operators of specific Boeing 747 aircraft to inspect and replace the handle straps on emergency descent devices (equipment used for emergency evacuation slides or escape systems).\n\n**Who it affects:**\n- All Boeing 747 models with \"line numbers\" (manufacturing serial numbers) 1 through 467 — essentially the earliest 747s built\n- Airlines, cargo operators, or any entity operating these specific aircraft in Australia\n\n**Why it matters:**\nOverseas inspections found that some descent devices had broken handle straps. A broken strap could prevent or delay emergency evacuation, putting passengers and crew at serious risk. This directive mandates a fix before a deadline to prevent accidents.\n\n**Key requirements:**\n- **Compliance deadline:** Before 1 March 1981\n- **Technical guidance:** Follow Boeing Alert Service Bulletin 747-25-A2551 and Frost Engineering Service Bulletin 379103-25-002\n- **Action required:** Inspect the handle straps and replace them if necessary"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is a focused safety requirement applying to all Boeing 747s with line numbers 1–467 and requires inspection and replacement per the two referenced service bulletins before a fixed date. The AD does not expand beyond that set of aircraft or beyond the single inspection/replacement requirement specified in the source text (Applicability; Documents; Compliance; Background)."},"complexity_factors":["Narrow applicability limited to Boeing 747 line numbers 1–467 (Applicability)","Single, time‑bound compliance action (inspect and replace before 1 March 1981) (Compliance)","Reliance on two external service bulletins for technical procedures (Documents)","Clear stated condition prompting action (broken handle straps found overseas) reduces ambiguity (Background)","No additional procedural layers, reporting requirements, or penalties stated in the text"],"plain_english_summary":"This AD mandates inspection—and replacement if needed—of descent‑device handle straps on Boeing 747 aeroplanes (line numbers 1–467) after reports of broken straps. Work must follow Boeing Alert SB No. 747‑25‑A2551 and Frost Engineering SB No. 379103‑25‑002 and be completed before 1 March 1981. Operators bear costs and schedule the mandated inspections to mitigate failure risk."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-26-descent-device-handle-strap-inspection-and-replacement","history":"/api/acts/ad-b747-26-descent-device-handle-strap-inspection-and-replacement/history","analysis":"/api/acts/ad-b747-26-descent-device-handle-strap-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-b747-26-descent-device-handle-strap-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-b747-26-descent-device-handle-strap-inspection-and-replacement/important-cases","documents":"/api/acts/ad-b747-26-descent-device-handle-strap-inspection-and-replacement/documents"}}