{"id":"F2006B02647","name":"AD/B727/125 - Upper Body Skin Bonded Tear Straps","slug":"ad-b727-125-upper-body-skin-bonded-tear-straps","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41963,"registerId":"commonwealth-F2006B02647-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/125 - Upper Body Skin Bonded Tear Straps","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/B727/125 Upper Body Skin Bonded Tear Straps 2/91\n\nApplicability: Model 727 referenced in Requirement Document.\n\n \n\nRequirement: Action in accordance with the technical requirements of FAA AD 90-20-18 Amdt 39-6747.\n\n \n\nNote: Boeing SB 727-53-0082 Revisions 3,4 and 5 refer.\n\n \n\nCompliance: As specified in the Requirement document with effective date 29 October 1990. Background:              Country of origin AD.\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":3,"scope_assessment":{"changed":false,"description":"The AD adopts and requires compliance with the FAA AD (90-20-18 Amdt 39-6747) and refers to the Boeing service bulletin; the text contains no provision that expands or narrows the FAA AD’s technical requirements. Applicability and required actions are determined by the referenced Requirement Document and external technical documents, so the AD’s scope is an adoption of the country-of-origin directive rather than a modification of it (Requirement; Note; Applicability; Compliance)."},"complexity_factors":["Relies on external documents (FAA AD 90-20-18 Amdt 39-6747) for the substantive technical requirements (Requirement)","References a manufacturer service bulletin (Boeing SB 727-53-0082 Revisions 3–5) rather than containing detailed instructions in the AD itself (Note)","Applicability is stated only by reference to the Requirement Document (Applicability), requiring users to obtain that document to determine which aircraft are affected","Prescriptive compliance deadline is given but operational specifics (inspection intervals, repair procedures) are delegated to the referenced documents (Compliance)","Technical subject matter (airframe tear straps) is inherently specialised and requires maintenance/engineering expertise to implement"],"plain_english_summary":"What this instrument does\n\n- This airworthiness directive (AD B/727/125) requires operators of the specified Boeing 727 aircraft to carry out the technical actions set out in a referenced FAA directive: “FAA AD 90-20-18 Amdt 39-6747.” (Requirement)\n\nWho it affects\n\n- It applies to Model 727 aeroplanes as set out in the Requirement Document. (Applicability)\n\nHow it works, mechanically\n\n- The Civil Aviation Safety Authority (CASA) has issued an AD that adopts the technical requirements of the FAA AD; operators must perform the actions “in accordance with the technical requirements of FAA AD 90-20-18 Amdt 39-6747.” (Requirement)\n- The AD also points operators to Boeing Service Bulletin SB 727-53-0082 Revisions 3, 4 and 5 for related technical detail. (Note)\n- Compliance must be carried out as specified in the Requirement Document and is effective from 29 October 1990. (Compliance)\n\nWhy it matters (official rationale and practical implications)\n\n- The directive concerns “Upper Body Skin Bonded Tear Straps” on Boeing 727 aeroplanes (title). The document states its source as a country-of-origin AD (Background), which indicates it aims to address an airworthiness issue identified by the FAA.\n- Mechanically, the directive makes compliance with the FAA AD and the referenced Boeing service bulletin mandatory for the listed aircraft in Australia (Requirement; Note; Compliance).\n\nWho pays, who decides, and what changes in behaviour\n\n- Who pays: Aircraft operators must obtain and follow the FAA AD and Boeing service bulletin and carry out the required inspections, repairs or modifications. Those actions will consume operator resources (maintenance labour, parts, aircraft downtime) because compliance is prescriptive. (Requirement; Note; Compliance)\n- Who decides: CASA issued the AD for Australian-registered aircraft but has adopted the FAA’s technical requirements as the substantive mandate. The FAA AD and Boeing service bulletin contain the technical decisions operators must follow. (Header; Requirement; Note)\n- Behaviour change required: Operators must locate the specified FAA AD and Boeing SB revision material, schedule and perform the mandated actions, and document compliance in line with the Requirement Document and the AD’s effective date. (Requirement; Note; Compliance)\n\nCosts, incentives and implementation trade-offs\n\n- Compliance imposes direct operational costs on the affected aircraft operators (inspection, repair, parts, and aircraft downtime). (Requirement; Compliance)\n- The CASA AD delegates the technical prescription to the FAA AD and Boeing SB, so operators’ compliance choices are constrained by those external technical documents; this reduces the scope for local variation but increases dependence on external documents and their correct interpretation. (Requirement; Note)\n- Administrative complexity arises because the AD’s text is brief and relies on separate documents (the FAA AD, the Boeing service bulletin, and the Requirement Document) for the operative technical and applicability details; operators and maintainers must consult those documents to determine exact actions, applicability, and timing. (Applicability; Requirement; Note; Compliance)\n\nImplementation risks and practical notes\n\n- Because the AD references external documents and specific revisions, there is a risk of misidentifying the correct FAA AD version or Boeing SB revision; operators must ensure they use the exact documents cited. (Requirement; Note)\n- The AD sets an effective date (29 October 1990); compliance scheduling and record-keeping must respect that date and any intervals or deadlines specified in the referenced Requirement Document and FAA AD. (Compliance)\n\nSource citations: Applicability; Requirement; Note; Compliance; Background."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive adopting a US FAA safety order. It has not expanded beyond its original purpose of addressing a specific structural defect in Boeing 727 aircraft. The scope remains precisely targeted at the identified safety issue."},"complexity_factors":["Extremely short document (approximately 150 words of substantive content)","Only 2 operative provisions: applicability and requirement","No defined terms section — relies entirely on external references (FAA AD and Boeing Service Bulletin)","No conditional logic, exceptions, or nested provisions","Single compliance date with no alternative methods or phased implementation","Content is essentially a pointer to other technical documents rather than standalone regulatory text"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order — issued by Australia's Civil Aviation Safety Authority (CASA) for **Boeing 727 aircraft**.\n\n**What it does:**\n- Requires owners and operators of Boeing 727 series aeroplanes to inspect and repair the **upper body skin bonded tear straps** — structural components that help prevent the fuselage from tearing apart under stress.\n- The work must follow the technical instructions set out in a US Federal Aviation Administration (FAA) directive (AD 90-20-18), which Australia has adopted.\n\n**Who it affects:**\n- Airlines, cargo operators, or any entity operating Boeing 727 aircraft in Australian airspace.\n- Maintenance engineers responsible for keeping these planes airworthy.\n\n**Why it matters:**\n- Tear straps are critical safety features. If they fail, the aircraft's fuselage could rupture during flight — potentially catastrophic.\n- This directive ensures Australian-registered Boeing 727s meet the same safety standards as those in the United States, where the original safety issue was identified.\n\n**Key details:**\n- **Compliance deadline:** 29 October 1990 (the effective date of the original US directive).\n- **Reference documents:** Boeing Service Bulletin 727-53-0082 (revisions 3, 4, and 5) provides the detailed repair instructions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-125-upper-body-skin-bonded-tear-straps","history":"/api/acts/ad-b727-125-upper-body-skin-bonded-tear-straps/history","analysis":"/api/acts/ad-b727-125-upper-body-skin-bonded-tear-straps/analysis","conflicts":"/api/acts/ad-b727-125-upper-body-skin-bonded-tear-straps/conflicts","importantCases":"/api/acts/ad-b727-125-upper-body-skin-bonded-tear-straps/important-cases","documents":"/api/acts/ad-b727-125-upper-body-skin-bonded-tear-straps/documents"}}