{"id":"F2006B07306","name":"AD/TB10/4 - Wing Flap Deflection - Modification","slug":"ad-tb10-4-wing-flap-deflection-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49298,"registerId":"commonwealth-F2006B07306-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/TB10/4 - Wing Flap Deflection - 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)  Aerospatiale (Socata) TB9 and TB10 (Tobago) Series Aeroplanes\n\n \n\nAD/TB10/4 Wing Flap Deflection - Modification 5/82\n\nApplicability: All TB10 aircraft from S/No. 1 up to and including S/No. 239. Document:  Rallye TB SB No. 10 GR.27.17.\n\nNote: Upon incorporation of this modification aircraft flight manuals should have amendment 4 incorporated and the contents of amendment 3 removed.\n\n \n\nCompliance: Before certification.\n\n \n\nBackground:  In order to maintain adequate longitudinal stability with full flap extended, maximum flap extension has been reduced from 32o to 25o30’. Additionally the forward C.G. limit is amended to 11% M.A.C. or .949m.\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 airworthiness issue in a limited production run of aircraft. The scope remains precisely limited to the stated serial numbers and the specific modification required. No scope creep is evident."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined technical parameters (flap angle reduction and C.G. limit)","Single applicability criterion (serial number range)","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","No conditional logic or nested exceptions","Straightforward compliance requirement ('Before certification')","Single background rationale provided"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety fix issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\n- Requires owners/operators of certain **Socata TB10 Tobago aeroplanes** (serial numbers 1 through 239) to modify their wing flaps before the aircraft can be certified as airworthy.\n- **The modification:** Reduces how far the flaps can extend — from 32 degrees down to 25 degrees 30 minutes — to prevent the aircraft from becoming unstable in flight when flaps are fully deployed.\n- Also tightens the **centre of gravity (C.G.) limits** — the forward limit is moved to 11% of the Mean Aerodynamic Chord (M.A.C., a technical measurement of the wing) or 0.949 metres.\n\n**Who it affects:**\n- Owners and operators of early-production TB10 Tobago aircraft (serial numbers 1–239).\n- Maintenance organisations servicing these aircraft.\n\n**Why it matters:**\n- **Flight safety.** Without this fix, these aircraft could experience poor longitudinal stability (tendency to pitch up or down unpredictably) with full flaps extended, potentially leading to loss of control during landing or slow-flight manoeuvres.\n- **Legal requirement.** This isn't optional — aircraft cannot be certified as airworthy until the modification is done.\n\n**Additional paperwork:** Once the physical modification is complete, the aircraft flight manual must be updated (amendment 4 added, amendment 3 removed)."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The directive narrows allowable aircraft configuration by reducing maximum flap extension from 32° to 25°30' and amends the forward C.G. limit to 11% M.A.C. / 0.949 m, thereby changing the operational and certification limits that applied before this modification (Background). The applicability remains confined to TB10 serial numbers 1 through 239 (Applicability), and the directive requires incorporation of the modification and flight manual amendments prior to certification (Compliance; Note)."},"complexity_factors":["Narrow technical scope: changes apply only to TB10 aircraft S/No. 1–239 (Applicability).","Single, specific modifications required: reduction of maximum flap angle and an amended forward C.G. limit (Background).","Clear compliance timing: must be done before certification (Compliance).","Prescriptive implementation reference: a single service bulletin is named as the procedural document (Document).","Administrative requirement to update flight manual pages and remove a specific amendment (Note)."],"plain_english_summary":"This directive requires owners/operators of Aerospatiale (Socata) TB10 serials 1–239 to incorporate a Rallye TB Service Bulletin modification and update the flight manual before certification. It reduces maximum flap deflection to 25°30' and sets the forward C.G. limit to 11% M.A.C. (0.949 m) to preserve longitudinal stability with full flaps. Compliance costs (modification, manuals, tests) fall to the aircraft owner/operator or certifying authority."}},"importantCases":[],"_links":{"self":"/api/acts/ad-tb10-4-wing-flap-deflection-modification","history":"/api/acts/ad-tb10-4-wing-flap-deflection-modification/history","analysis":"/api/acts/ad-tb10-4-wing-flap-deflection-modification/analysis","conflicts":"/api/acts/ad-tb10-4-wing-flap-deflection-modification/conflicts","importantCases":"/api/acts/ad-tb10-4-wing-flap-deflection-modification/important-cases","documents":"/api/acts/ad-tb10-4-wing-flap-deflection-modification/documents"}}