{"id":"F2006B02797","name":"AD/B727/92 - Take-Off Warning System - Modification","slug":"ad-b727-92-take-off-warning-system-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42139,"registerId":"commonwealth-F2006B02797-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/92 - Take-Off Warning System - 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/B727/92 Take-Off Warning System - Modification 3/83\n\nApplicability: All model 727 aeroplanes with S/Nos. listed in the requirement document. Document:              Boeing SB 727-31-52.\n\nNote: FAA AD 80-22-12 Amendment 39-3951 refers.\n\n \n\nCompliance: Before 31 March 1985.\n\n \n\nBackground: To ensure that flight crew have positive warning when the leading edge devices are not extended for take-off.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-limited safety directive. It has not expanded beyond its original purpose of mandating a specific modification to address a known take-off safety risk."},"complexity_factors":["Extremely short document (under 200 words)","Only 4 operative provisions: applicability, document reference, compliance date, and background","No defined terms section","No cross-references to other legislation (only a non-binding note about the FAA AD)","Single unconditional requirement with fixed deadline","No exceptions, exemptions, or conditional logic"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA).\n\n**What it requires:** All Boeing 727 aircraft with specific serial numbers must be modified to install or upgrade a **Take-Off Warning System**. This is a cockpit alert that warns pilots if the plane's leading edge flaps/slats (the movable surfaces on the front of the wings) aren't properly extended for take-off.\n\n**Why it matters:** If a pilot tries to take off with the leading edge devices retracted, the aircraft won't generate enough lift at low speeds. This has caused fatal crashes. The warning system acts as a last-line safety net to catch human error before the plane leaves the ground.\n\n**Who must comply:** Operators of affected Boeing 727 series aircraft (specific serial numbers listed in Boeing Service Bulletin 727-31-52).\n\n**Deadline:** The modification had to be completed before 31 March 1985.\n\n**Key point:** This directive aligns with a US Federal Aviation Administration (FAA) order (AD 80-22-12), showing how Australia harmonises its aviation safety rules with international standards."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument's operative scope is to require a specific modification to the take-off warning system on Model 727 aeroplanes identified by serial number and to set a compliance date. That scope, as expressed in the Applicability, Document and Compliance clauses, aligns with the stated purpose in the Background (ensuring a positive warning when leading edge devices are not extended). No text in the supplied instrument indicates an expansion or narrowing of that stated scope from its expressed purpose."},"complexity_factors":["Technical requirement relies on an external manufacturer service bulletin (Document: Boeing SB 727-31-52).","Need to identify affected aircraft by serial number listed in the requirement document (Applicability).","Firm compliance deadline creates scheduling and operational coordination challenges (Compliance).","Cross-reference to an FAA AD introduces an inter-jurisdictional regulatory dimension (Note).","Practical complexity of a hardware/system modification requiring qualified maintenance resources and parts (implied by Document and Background)."],"plain_english_summary":"Requires specified Boeing 727 owners/operators to install a modification to the take-off warning system per Boeing SB 727-31-52 by 31 March 1985, ensuring crews receive a positive warning if leading-edge devices aren’t extended. Costs, scheduling and compliance fall to operators; the AD mirrors related FAA action (FAA AD 80-22-12)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-92-take-off-warning-system-modification","history":"/api/acts/ad-b727-92-take-off-warning-system-modification/history","analysis":"/api/acts/ad-b727-92-take-off-warning-system-modification/analysis","conflicts":"/api/acts/ad-b727-92-take-off-warning-system-modification/conflicts","importantCases":"/api/acts/ad-b727-92-take-off-warning-system-modification/important-cases","documents":"/api/acts/ad-b727-92-take-off-warning-system-modification/documents"}}