{"id":"F2006B06544","name":"AD/RB211/13 - Thrust Reverser Functional Test","slug":"ad-rb211-13-thrust-reverser-functional-test","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48243,"registerId":"commonwealth-F2006B06544-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/RB211/13 - Thrust Reverser Functional Test","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 - 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Rolls Royce Turbine Engines - RB211 Series\n\n \n\nAD/RB211/13 Thrust Reverser Functional Test 6/91\n\nApplicability: All RB211-524G and 524H engines not incorporating the requirements of Rolls Royce Service Bulletin RB211-78-9347.\n\n \n\nRequirement: Action in accordance with the requirements of Rolls Royce Mandatory Service Bulletin RB211-78-9274.\n\n \n\nCompliance: As detailed in Requirement Document.\n\n \n\nBackground: This Directive requires a functional test to be carried out following any abandoned take-off where the thrust reversers have been deployed. This requirement reflects advice that following an abandoned take-off, thrust reverser operation times may become extended (10 seconds or more).\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":"This directive does not expand the categories of engines regulated beyond the specified RB211‑524G and RB211‑524H models; instead it imposes an additional, event‑triggered operational test for those engines unless they have incorporated the modifications required by Rolls‑Royce Service Bulletin RB211‑78‑9347. The change is procedural (a required functional test after a defined event) rather than a widening of regulatory scope. (Applicability; Requirement; Background)"},"complexity_factors":["Narrow applicability limited to RB211‑524G and RB211‑524H engines and excluding engines with SB RB211‑78‑9347 (Applicability)","Event‑triggered compliance: test obligation arises only after an abandoned take‑off where reversers were deployed (Background)","Dependence on an external manufacturer document (Rolls‑Royce Mandatory Service Bulletin RB211‑78‑9274) for procedural detail (Requirement; Compliance)","Concise drafting that defers technical specifics to the Service Bulletin, requiring operators to obtain and interpret an external technical document (Requirement; Compliance)","Operational and logistical impacts (downtime, labour) driven by frequency of the triggering event rather than by a fixed schedule (Background)"],"plain_english_summary":"This airworthiness directive requires operators of Rolls‑Royce RB211‑524G/524H engines (unless modified by SB RB211‑78‑9347) to perform the thrust‑reverser functional test after any abandoned take‑off where reversers were used, following Rolls‑Royce Mandatory Service Bulletin RB211‑78‑9274. It aims to detect extended reverser operation times; operators bear the testing and any remedial maintenance costs and must follow the manufacturer’s procedure for compliance."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive focused on a specific safety concern with specific engine models. It has not expanded beyond its original purpose of ensuring thrust reverser functionality after aborted take-offs."},"complexity_factors":["Very short document (under 200 words)","Only 2 defined applicability criteria (engine models and service bulletin exclusion)","Single requirement referencing an external technical document","No nested conditions, exceptions, or cross-references to other legislation","Straightforward compliance trigger (aborted take-off with reverser deployment)"],"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) that requires specific maintenance actions on aircraft engines.\n\n**What it does:** It orders operators of certain Rolls-Royce RB211 jet engines (specifically the -524G and -524H models) to perform a functional test on the thrust reversers after any aborted take-off where the reversers were used.\n\n**Why it matters:** After an aborted take-off, the thrust reversers (the devices that push engine thrust forward to help slow the aircraft) can take longer than normal to stow — up to 10 seconds or more instead of the usual quick response. This delay could be dangerous if not detected, as partially deployed reversers during a subsequent take-off attempt could cause asymmetric thrust or control problems.\n\n**Who must comply:** Airlines and aircraft operators using RB211-524G or -524H engines that haven't been modified according to Rolls-Royce Service Bulletin RB211-78-9347.\n\n**What must be done:** Operators must follow the specific testing procedures laid out in Rolls-Royce Mandatory Service Bulletin RB211-78-9274. The exact timing for completing this test is specified in that document."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rb211-13-thrust-reverser-functional-test","history":"/api/acts/ad-rb211-13-thrust-reverser-functional-test/history","analysis":"/api/acts/ad-rb211-13-thrust-reverser-functional-test/analysis","conflicts":"/api/acts/ad-rb211-13-thrust-reverser-functional-test/conflicts","importantCases":"/api/acts/ad-rb211-13-thrust-reverser-functional-test/important-cases","documents":"/api/acts/ad-rb211-13-thrust-reverser-functional-test/documents"}}