{"id":"F2006B10828","name":"AD/INST/26 - Navomatic 200A Automatic Pilot Computer - Amplifier Nav Input - Modification","slug":"ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56306,"registerId":"commonwealth-F2006B10828-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/INST/26 - Navomatic 200A Automatic Pilot Computer - Amplifier Nav Input - 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 - 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/26  Navomatic 200A Automatic Pilot Computer - Amplifier Nav Input - Modification\n\n\n1/79\n\n \n\nApplicability: ARC CA-295B computer-amplifiers up to S/No. 3550 that connect to a navigation signal having a significant DC voltage from earth.\n\n \n\nDocument: 1. ARC Field Engineering SB 211; or\n\n \n\n2. Cessna Avionics SL AV78-28.\n\n \n\nCompliance: Within 200 hours time in service after 31 January 1979.\n\n \n\nBackground: This Directive introduces a modification by which a computer amplifier may accept voltages of up to 'plus' 8 volts.\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":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1269},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow technical scope targeting specific ARC CA-295B autopilot computer-amplifiers. It has not expanded beyond the specific voltage tolerance modification originally intended for this equipment."},"complexity_factors":["Narrow, specific applicability limited to one model with defined serial number range","Single straightforward compliance requirement (time-based deadline)","Only two external reference documents cited","No defined terms, exceptions, or conditional clauses"],"plain_english_summary":"**What this is:** A mandatory safety directive (an \"Airworthiness Directive\") requiring a specific hardware fix for certain aircraft autopilot systems.\n\n**Who it affects:** Owners or operators of aircraft fitted with **ARC CA-295B computer-amplifiers** (serial numbers up to 3550) that connect to navigation signals carrying a significant DC voltage from earth (ground).\n\n**What you must do:** Modify the autopilot computer so it can safely accept voltages up to positive 8 volts. The technical instructions are found in either:\n* ARC Field Engineering Service Bulletin 211; or\n* Cessna Avionics Service Letter AV78-28\n\n**Deadline:** Complete the modification within 200 hours of flight time after 31 January 1979.\n\n**Why this matters:** Without this modification, the autopilot could malfunction when processing navigation signals with certain electrical characteristics, potentially causing loss of automatic flight control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification","history":"/api/acts/ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification/history","analysis":"/api/acts/ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification/analysis","conflicts":"/api/acts/ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification/conflicts","importantCases":"/api/acts/ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification/important-cases","documents":"/api/acts/ad-inst-26-navomatic-200a-automatic-pilot-computer-amplifier-nav-input-modification/documents"}}