{"id":"F2006B05280","name":"AD/CESSNA 207/21 Amdt 1 - Alternator Ground Strap","slug":"ad-cessna-207-21-amdt-1-alternator-ground-strap","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":45664,"registerId":"commonwealth-F2006B05280-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 207/21 Amdt 1 - Alternator Ground Strap","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 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Cessna 207 Series Aeroplanes\n\n \n\nAD/CESSNA 207/21\n\nAmdt 1\n\n\nAlternator Ground Strap 9/82\n\n \n\nApplicability: All model 207 with S/Nos 20700001 to 20700451. Requirement:  Action in accordance with Cessna SIL SE79-59.\n\nNote: FAA AD 79-25-07 refers.\n\n \n\nCompliance: 1. Within 100 hours time in service after 31 March 1982.\n\n \n\n2. Each time an engine is installed in an aircraft following initial compliance.\n\n \n\nBackground: Compliance has been amended with the addition of item 2 due to reports from industry that ground straps are being omitted from refitment on engine reinstallations.\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":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"The original AD likely only required a one-time inspection by 31 March 1982. Amendment 1 expanded the scope to include a recurring requirement — checking the ground strap every time an engine is reinstalled. This transformed a finite compliance task into an ongoing maintenance obligation, significantly extending the directive's practical reach over the aircraft's operational life."},"complexity_factors":["Extremely short document (under 200 words)","Only 1 defined applicability criterion (serial number range)","Single technical reference to external document (Cessna SIL SE79-59)","Simple two-part compliance structure with clear deadlines","No nested conditions, exceptions, or cross-references to other legislation","Background explanation is straightforward narrative, not legal conditional logic"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for specific Cessna 207 aircraft.\n\n**What it does:**\n- Requires owners/operators of certain Cessna 207 planes (serial numbers 20700001 through 20700451) to inspect and fix a problem with the **alternator ground strap** — a safety-critical electrical connection that prevents dangerous electrical faults.\n\n**Who must follow it:**\n- Anyone operating or maintaining the affected Cessna 207 aircraft models.\n\n**What action is required:**\n- Follow the instructions in **Cessna Service Information Letter SE79-59** (a technical bulletin from the manufacturer).\n- **First deadline:** Complete the work within 100 flight hours after 31 March 1982.\n- **Ongoing requirement:** Every time an engine is removed and reinstalled, you must check the ground strap again — this was added because mechanics were forgetting to reconnect these straps during engine work.\n\n**Why it matters:**\n- Missing or faulty ground straps can cause electrical failures or fires. The amendment (Amdt 1) closes a loophole where straps were being left off during engine maintenance, creating a recurring safety risk."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Yes. The directive's compliance scope was amended by adding the requirement that the ground strap action be carried out each time an engine is installed following initial compliance. The Background states this addition was made because industry reported that ground straps were being omitted when engines were refitted (\"Background\" and \"Compliance 2\")."},"complexity_factors":["Narrow applicability limited to specific serial-number range (20700001–20700451) (\"Applicability\").","Required action is defined by an external document (Cessna SIL SE79-59), which requires users to obtain and follow that service instruction (\"Requirement\").","Two compliance triggers: a time-in-service deadline (within 100 hours after 31 March 1982) and a recurring trigger on each engine installation (\"Compliance 1\", \"Compliance 2\").","Reference to an external foreign directive (FAA AD 79-25-07) for cross-checking but not specified procedure (\"Note\").","Short text with limited procedural detail — the AD delegates the technical method to the referenced service instruction, concentrating complexity in that external document (\"Requirement\")."],"plain_english_summary":"This directive requires fitting or checking/correcting an alternator ground strap on Cessna 207 aircraft serials 20700001–20700451 in accordance with Cessna Service Instruction Letter SE79-59, with initial compliance within 100 hours TIS after 31 Mar 1982 and repeated whenever an engine is installed. \n\nIssued by CASA, it binds aircraft operators and maintenance providers to follow the manufacturer instruction, imposing labour/parts costs to reduce the safety risk identified when straps were omitted during engine reinstallation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-207-21-amdt-1-alternator-ground-strap","history":"/api/acts/ad-cessna-207-21-amdt-1-alternator-ground-strap/history","analysis":"/api/acts/ad-cessna-207-21-amdt-1-alternator-ground-strap/analysis","conflicts":"/api/acts/ad-cessna-207-21-amdt-1-alternator-ground-strap/conflicts","importantCases":"/api/acts/ad-cessna-207-21-amdt-1-alternator-ground-strap/important-cases","documents":"/api/acts/ad-cessna-207-21-amdt-1-alternator-ground-strap/documents"}}