{"id":"F2006B02753","name":"AD/B727/51 - Right Hand Inboard Midflap Trailing Edge Upper Chord Support Angle - Reinforcement","slug":"ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42095,"registerId":"commonwealth-F2006B02753-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/51 - Right Hand Inboard Midflap Trailing Edge Upper Chord Support Angle - Reinforcement","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/B727/51 Right Hand Inboard Midflap Trailing Edge Upper\n\nChord Support Angle - Reinforcement\n\n\n6/67\n\n \n\nApplicability: All models. Document: Boeing SB No. 27-97. Compliance: Forthwith.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific structural component on a specific aircraft type. It has not expanded beyond its original purpose of mandating a particular reinforcement repair."},"complexity_factors":["Extremely short document (approximately 100 words of substantive content)","Single, unambiguous applicability clause ('All models')","No defined terms section — technical terms reference external Boeing documentation","No conditional logic, exceptions, or nested provisions","Single compliance requirement with immediate effect ('Forthwith')","No cross-references to other legislation or regulations beyond the enabling Civil Aviation Regulations 1998"],"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 **Boeing 727 series aeroplanes** to reinforce a specific structural part on the right-hand side of the aircraft — the \"inboard midflap trailing edge upper chord support angle.\" This is a metal bracket or support piece near the trailing edge of the middle section of the wing flap.\n\n**Who it affects:**\nAnyone who owns, operates, or maintains Boeing 727 aircraft in Australia (all models are covered).\n\n**Why it matters:**\nThis directive addresses a structural weakness that could lead to fatigue cracking or failure of the flap support structure. If left unrepaired, this could compromise the aircraft's control surfaces and potentially affect flight safety. The word \"Forthwith\" means this must be done immediately — there's no grace period.\n\n**How to comply:**\nOperators must follow the technical instructions in **Boeing Service Bulletin No. 27-97** to reinforce the specified component."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text provided does not indicate any change in scope from an earlier statement within this instrument: applicability is stated as \"All models\" and the AD prescribes reinforcement with reference to Boeing SB No. 27-97 to be done forthwith (\"Applicability: All models\"; \"Document: Boeing SB No. 27-97\"; \"Compliance: Forthwith\"). There is no indication in the supplied text of an expansion or narrowing of scope compared with an original intent."},"complexity_factors":["Short, narrowly focused directive specifying a single structural reinforcement (low textual complexity).","Immediate compliance requirement (\"Forthwith\") increases operational scheduling complexity for affected operators.","Technical work is delegated to an external Boeing service bulletin (Document: Boeing SB No. 27-97), requiring technical expertise to interpret and implement.","Applies to all models of the Boeing 727 series (broad applicability increases number of affected operators but does not add legal complexity).","No alternative compliance procedures, waivers, or staged deadlines are stated in the text provided, reducing procedural flexibility but simplifying legal reading."],"plain_english_summary":"Mandates reinforcement of the right‑hand inboard midflap trailing‑edge upper‑chord support angle on all Boeing 727 series aircraft, to be carried out using Boeing Service Bulletin No. 27‑97, with compliance required forthwith. \n\nAll operators, owners and maintenance organisations must implement the bulletin immediately; operators will bear parts, labour and downtime costs and no deferral or alternative compliance is stated."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement","history":"/api/acts/ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement/history","analysis":"/api/acts/ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement/analysis","conflicts":"/api/acts/ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement/conflicts","importantCases":"/api/acts/ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement/important-cases","documents":"/api/acts/ad-b727-51-right-hand-inboard-midflap-trailing-edge-upper-chord-support-angle-reinforcement/documents"}}