{"id":"F2006B09622","name":"AD/F100/21 - Reverse Thrust Control Maximum Detent","slug":"ad-f100-21-reverse-thrust-control-maximum-detent","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54392,"registerId":"commonwealth-F2006B09622-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F100/21 - Reverse Thrust Control Maximum Detent","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nFokker F100 (F28 Mk 100) Series Aeroplanes\n\nAD/F100/21 Reverse Thrust Control Maximum Detent 4/99\n\nApplicability: F.28 Mk.0100 aircraft, serial numbers 11244 to 11261, 11263 and 11268 through\n\n11283.\n\nRequirement: Replace the maximum reverse thrust control detent in accordance with Part 2 of the Accomplishment Instructions of Fokker Service Bulletin (SB) F100-76-010 dated 31 October 1993.\n\nNote: RLD BLA 93-151(A) refers.\n\nCompliance: Unless previously accomplished, within 500 flight cycles from the effective date of this AD.\n\nThis Airworthiness Directive becomes effective on 22 April 1999.\n\nBackground: Some F.28 Mk.0100 operators reported that the override force for the normal maximum detent of the reverse thrust control was too low. This condition, if not corrected, can result in the inadvertent selection of a too high reverse thrust level, which in turn affects the structural life of the horizontal stabiliser attachment.\n\nSubsequent modifications may not have provided adequate clearance between the new detents and the surrounding parts. The modification required by this AD provides adequate clearance.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1695},"content_quality":"ok","complexity_score":2,"rejection_reason":"","scope_assessment":{"changed":false,"description":"This directive remains precisely targeted at its original purpose: mandating a specific hardware modification to address the documented safety defect in the reverse thrust control mechanism. There is no evidence of scope creep or expansion beyond the original mechanical safety issue."},"complexity_factors":["Narrow applicability limited to specific aircraft serial numbers","Single concrete technical requirement with no exceptions or conditional provisions","Cross-reference to external technical standard (Fokker Service Bulletin) for detailed accomplishment instructions","Simple time-based compliance metric (flight cycles) with no alternative compliance methods","No defined terms, interpretation sections, or nested logic"],"plain_english_summary":"This airworthiness directive orders operators of select Fokker F100 jets (s/n 11244–11261, 11263, 11268–11283) to correct a weak reverse-thrust detent that can allow excessive reverse thrust and overstress the horizontal stabiliser.  \n\nAffected aircraft must have the maximum reverse-thrust control detent replaced per Fokker Service Bulletin F100-76-010 (31 Oct 1993) within 500 flight cycles to prevent structural damage and ensure continued airworthiness."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f100-21-reverse-thrust-control-maximum-detent","history":"/api/acts/ad-f100-21-reverse-thrust-control-maximum-detent/history","analysis":"/api/acts/ad-f100-21-reverse-thrust-control-maximum-detent/analysis","conflicts":"/api/acts/ad-f100-21-reverse-thrust-control-maximum-detent/conflicts","importantCases":"/api/acts/ad-f100-21-reverse-thrust-control-maximum-detent/important-cases","documents":"/api/acts/ad-f100-21-reverse-thrust-control-maximum-detent/documents"}}