{"id":"F2006B10812","name":"AD/INST/11 - Automatic Pilot Servo Actuators - Inspection","slug":"ad-inst-11-automatic-pilot-servo-actuators-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56290,"registerId":"commonwealth-F2006B10812-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/INST/11 - Automatic Pilot Servo Actuators - Inspection","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 - 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Instruments and Automatic Pilots\n\n \n\nAD/INST/11 Automatic Pilot Servo Actuators - Inspection 6/74\n\nApplicability: Automatic Pilot Servo Actuators Type PA500A below S/No. 3000, Type PA520A below S/No. 2800, and Type PA520B below S/No. 1500, without a white dot painted either adjacent to or on the actuator nameplate.\n\n \n\nDocument: 1. Cessna Avionics SL AV 74-3 and ARC SB No. 171; or 2. FAA AD 74-08-01.\n\nCompliance: Within 100 hours time in service after 28 June 1974.\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 mechanical defect in specific aircraft components. It has not expanded beyond its original narrow technical scope. The document represents the original 1974 directive without subsequent amendments visible in this extract."},"complexity_factors":["Very short document (approximately 150 words)","Only 3 defined applicability criteria (actuator types and serial number ranges)","Single visual identification marker (white dot) for exemption","Simple binary compliance condition (inspection required vs. white dot present)","No cross-references to other legislation sections","Single compliance deadline with straightforward calculation method (100 hours time in service)","References to external technical documents but doesn't incorporate them by complex textual integration"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific aircraft to inspect certain automatic pilot servo actuators (components that help control the plane automatically).\n\n**What it does:**\n- Mandates inspection of specific models of automatic pilot servo actuators made by a manufacturer (likely Cessna/ARC based on the referenced documents)\n- Applies to older serial numbers of three specific actuator types: PA500A, PA520A, and PA520B\n- Only applies if the actuator **doesn't** have a white dot painted near or on its nameplate (the white dot indicates the fix has already been applied)\n\n**Who it affects:**\n- Aircraft owners and operators with these specific servo actuators installed\n- Maintenance organisations responsible for airworthiness compliance\n\n**Why it matters:**\n- These components are critical for automatic flight control. A failure could compromise aircraft control.\n- The directive references a 1974 FAA safety directive and manufacturer service bulletins, suggesting this addresses a known safety defect discovered in the early 1970s.\n- Non-compliance means the aircraft cannot be considered airworthy — it would be illegal to fly.\n\n**Compliance deadline:**\n- The inspection had to be completed within 100 hours of flight time after 28 June 1974. (Note: This is a historical directive from 1974, so compliance would have been required decades ago for any aircraft still operating with these legacy components.)"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The text itself sets a narrow and explicit scope: inspection applies only to specified actuator types below stated serial numbers and only if the white-dot marking is absent (Applicability). The directive prescribes the inspection method by reference and a single compliance deadline (Document; Compliance). There is no text in the instrument indicating a broader or different scope from that prescription, so there is no indication in the supplied text that the scope has changed from its original, stated coverage."},"complexity_factors":["Narrow applicability defined by specific actuator types and serial-number thresholds (Applicability).","Conditional applicability tied to a visible marking (absence of a white dot), which requires physical inspection to establish applicability (Applicability).","Mandate to follow one of two external technical documents, which delegates procedural detail outside the directive text (Document).","A single, short compliance window (100 hours time in service after 28 June 1974) creates a time-sensitive operational burden (Compliance)."],"plain_english_summary":"This airworthiness directive requires owners/operators to have specific automatic‑pilot servo actuators inspected (limited by model, serial‑number ranges and absence of a white dot) within 100 hours TIS after 28 June 1974, using one of the referenced Cessna/FAA procedures. Maintenance providers carry out the work; costs and downtime fall to the aircraft owner/operator. CASA mandates and enforces the requirement, while the referenced service documents govern the technical inspection and any corrective actions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-11-automatic-pilot-servo-actuators-inspection","history":"/api/acts/ad-inst-11-automatic-pilot-servo-actuators-inspection/history","analysis":"/api/acts/ad-inst-11-automatic-pilot-servo-actuators-inspection/analysis","conflicts":"/api/acts/ad-inst-11-automatic-pilot-servo-actuators-inspection/conflicts","importantCases":"/api/acts/ad-inst-11-automatic-pilot-servo-actuators-inspection/important-cases","documents":"/api/acts/ad-inst-11-automatic-pilot-servo-actuators-inspection/documents"}}