{"id":"F2006B11148","name":"AD/LEARJET/30 Amdt 2 - Flap System and Flap Sector Mounting Brackets","slug":"ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56837,"registerId":"commonwealth-F2006B11148-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/LEARJET/30 Amdt 2 - Flap System and Flap Sector Mounting Brackets","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)  Gates Learjet 24 & 25 Series Aeroplanes\n\n \n\nAD/LEARJET/30\n\nAmdt 2\n\n\nFlap System and Flap Sector Mounting Brackets\n\n\n1/87\n\n \n\nApplicability: All model Learjet with S/Nos. listed in requirement documents. Requirement: Modify in accordance with Gates Learjet SB AMK 86-4.\n\nCompliance: Within 100 hours time in service or at the next inspection for Maintenance Release issue after 31 January 1987, whichever is later.\n\n \n\nBackground:  This Directive was originally issued due to cracking in the flap sector mounting brackets. This amendment replaces the aluminium brackets with steel items and terminates any further requirement.\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":true,"description":"The amendment changes the remedial approach from the prior state (which prompted the original directive because of cracking) to a definitive replacement: aluminium flap sector mounting brackets are to be replaced with steel brackets, and the amendment \"terminates any further requirement\" once the modification is completed. In other words, the instrument moves from an ongoing or interim response to a one-off modification cure, as stated in the Background."},"complexity_factors":["Narrow technical scope: applies only to Learjet 24 & 25 with specified serial numbers (Applicability).","Single, discrete technical remedy: replacement of aluminium brackets with steel per a single service bulletin (Requirement).","Clear compliance window: 100 hours TIS or next Maintenance Release after a specified date (Compliance).","Dependence on external technical document: requires following Gates Learjet SB AMK 86-4, adding a dependency on that bulletin for procedural detail (Requirement).","Operational logistics: sourcing parts, scheduling maintenance and downtime introduce practical complexity despite simple regulatory text (Requirement; Compliance)."],"plain_english_summary":"Owners/operators of specified Gates Learjet 24 and 25 serial numbers must replace aluminium flap sector mounting brackets with steel ones, performed per Gates Learjet Service Bulletin AMK 86-4 and signed off by qualified maintenance. The work is due within 100 flight hours or at the next Maintenance Release after 31 January 1987. The amendment fixes bracket cracking, eliminates further directive actions once installed, and imposes one‑off parts, labor and downtime costs on operators."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD remains tightly focused on its original purpose: addressing a specific structural defect in Learjet flap mounting brackets. The amendment simply updates the technical solution (steel replacing aluminium) and closes out the directive — it has not expanded to cover other aircraft systems or unrelated safety issues."},"complexity_factors":["Very short document (under 200 words)","Only 3 defined elements: applicability, requirement, and compliance","No cross-references to other legislation beyond a single service bulletin reference","Simple conditional logic (compliance deadline uses basic 'whichever is later' test)","Single amendment terminating previous requirements — no nested exceptions"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:** It requires owners and operators of certain Gates Learjet 24 and 25 series aircraft to replace aluminium flap sector mounting brackets with stronger steel ones. The \"flap sector mounting brackets\" are structural parts that hold the flaps in place — flaps are the movable surfaces on the wings that help slow the plane down for landing. Cracks had been found in the original aluminium brackets, creating a safety risk.\n\n**Who it affects:** Anyone who owns or operates a Learjet 24 or 25 series aircraft with a serial number listed in the referenced service bulletin (Gates Learjet SB AMK 86-4).\n\n**What must be done:** The modification must be completed within 100 hours of flight time, or at the next scheduled inspection for issuing a Maintenance Release (a document certifying an aircraft is safe to fly) — whichever comes later, but only counting from 31 January 1987 onwards.\n\n**Why it matters:** Cracked mounting brackets could cause the flaps to fail, potentially leading to loss of control during landing. This amendment (version 2) makes the fix permanent by switching to steel brackets and removes any ongoing inspection requirements once the modification is done."}},"importantCases":[],"_links":{"self":"/api/acts/ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets","history":"/api/acts/ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets/history","analysis":"/api/acts/ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets/analysis","conflicts":"/api/acts/ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets/conflicts","importantCases":"/api/acts/ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets/important-cases","documents":"/api/acts/ad-learjet-30-amdt-2-flap-system-and-flap-sector-mounting-brackets/documents"}}