{"id":"F2006B10830","name":"AD/INST/28 - A.R.C. PA1050A Actuator and DA-1050A Decoupler Adapter - Cessna 1050A I.F.C.S. - Inspection and Modification","slug":"ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56308,"registerId":"commonwealth-F2006B10830-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/INST/28 - A.R.C. PA1050A Actuator and DA-1050A Decoupler Adapter - Cessna 1050A I.F.C.S. - Inspection and Modification","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nInstruments and Automatic Pilots\n\nAD/INST/28 A.R.C. PA1050A Actuator and DA-1050A Decoupler Adapter - Cessna 1050A I.F.C.S. - Inspection and\n\nModification\n\n  \n11/79\n\nApplicability: All PA-1050A actuators ARC P/N 46220-2900 S/Nos. 001 to 599 not incorporating Mod. 2 and all DA-1050A decoupler adapters ARC P/N 47720-0000 S/Nos. 001 to 389 not incorporating Mod. 1 and Mod. 3.\n\nDocument: 1. ARC Field Engineering SB No. 215; or\n\n2. Cessna Information Letter AV79-26 (Cessna 441 aircraft).\n\nCompliance: 1. Inspection \\- At intervals not exceeding 100 hours time in service until modified.\n\n2. Modification \\- Before 30 November 1980.\n\nBackground: Actuators and decoupler adapters of ARC IF 1050A (Cessna 1050A) flight control system have corroded and failed due to inadequate protection from water.\n\nModifications to these units will improve their corrosion resistance.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2200},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow technical scope targeting specific ARC components within Cessna 1050A flight control systems to remediate a defined corrosion safety defect. It has not expanded beyond its initial equipment-specific remedial purpose."},"complexity_factors":["Narrow applicability limited to specific manufacturer part numbers and serial number ranges","Assumes technical knowledge of aviation terms ('time in service', 'Mod' levels, 'decoupler adapter')","References external technical service bulletins without reproducing their content","Short, single-purpose directive with straightforward compliance deadlines"],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Cessna 1050A Integrated Flight Control Systems to inspect and modify specific ARC PA-1050A actuators (S/N 001–599) and DA-1050A decoupler adapters (S/N 001–389) unless already upgraded (Mod. 1–3).  \n\nInspect for corrosion every 100 hours until upgraded, and install the water-sealing corrosion protection modification by 30 November 1980 to prevent control-surface failure from corrosion-induced component loss."}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and","history":"/api/acts/ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and/history","analysis":"/api/acts/ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and/analysis","conflicts":"/api/acts/ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and/conflicts","importantCases":"/api/acts/ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and/important-cases","documents":"/api/acts/ad-inst-28-a-r-c-pa1050a-actuator-and-da-1050a-decoupler-adapter-cessna-1050a-i-f-c-s-inspection-and/documents"}}