{"id":"F2006B10103","name":"AD/G164/18 Amdt 1 - Aileron Bellcrank - Inspection and Modification","slug":"ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55607,"registerId":"commonwealth-F2006B10103-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G164/18 Amdt 1 - Aileron Bellcrank - Inspection and Modification","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nSchweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes\n\nAD/G164/18\n\nAmdt 1\n\n  \nAileron Bellcrank \\- Inspection and Modification 8/82\n\nApplicability: All models G-164B with S/Nos. 1B to 656B; G164C with S/Nos. 1C to 44C;\n\nG-164D with S/Nos. 1D to 16D.\n\nDocument: Gulfstream American AG-CAT SB No. 75 Revision A.\n\nNote: FAA AD 82-13-06 refers.\n\nCompliance: 1. Unless already accomplished, inspect initially within 100 hours time in service after 31 August 1982, and thereafter at intervals of 300 hours time in service until modified.\n\n2. If excessive elongation is found during inspection, modify or replace the bellcrank before further flight.\n\nBackground: Conditions continue to exist whereby failure of the aileron cable attachment at the LH and RH aileron bellcrank assemblies may occur.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is an amendment (Amdt 1) to an existing Airworthiness Directive, but the scope remains tightly focused on the original safety issue: aileron bellcrank inspections for specific Ag-Cat aircraft. The amendment does not appear to expand applicability to new aircraft models or introduce new types of requirements beyond the original inspection and modification mandate."},"complexity_factors":["Very short document (approximately 150 words)","Only 3 defined applicability criteria (serial number ranges for three model variants)","Single cross-reference to FAA AD 82-13-06 and one service bulletin","Simple conditional logic: only two compliance paths (inspect on schedule, or modify/replace if defect found)","No nested exceptions or layered definitions","Straightforward temporal trigger (100 hours after fixed date, then 300-hour intervals)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nOrders owners and operators of certain **Schweizer (Grumman) G-164 \"Ag-Cat\" agricultural aircraft** to inspect and potentially modify a critical flight control component called the **aileron bellcrank** (a lever that helps move the wing flaps that control the plane's roll).\n\n**Who it affects:**\n- All G-164B models with serial numbers 1B to 656B\n- All G-164C models with serial numbers 1C to 44C  \n- All G-164D models with serial numbers 1D to 16D\n\n**What must be done:**\n- **Initial inspection:** Within 100 hours of flight time after 31 August 1982\n- **Ongoing inspections:** Every 300 hours of flight time until the modification is done\n- **If problems found:** The bellcrank must be modified or replaced **before the aircraft flies again**\n\n**Why it matters:**\nThe aileron cable attachment points on the left and right bellcrank assemblies can fail. If this happens in flight, the pilot could lose control of the aircraft's ability to bank and turn — a serious safety risk. This directive prevents crashes by catching wear before it becomes catastrophic.\n\n**Key reference:** Operators must follow **Gulfstream American Service Bulletin No. 75 Revision A** for the exact inspection and modification procedures."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"This entry is an amendment (Amdt 1) to the AD for the G‑164 series. Mechanically it prescribes a defined initial inspection window (within 100 hours after 31 August 1982) and recurring 300‑hour inspections until the bellcrank is modified, and it mandates modification or replacement before further flight if excessive elongation is found (Compliance 1–2). It therefore clarifies and sets enforceable timing and remedial steps for the aileron bellcrank condition for the listed serial numbers (Applicability; Compliance 1–2)."},"complexity_factors":["Multiple affected models and narrow serial‑number ranges (Applicability) which require operators to check fleet eligibility.","Recurring inspection schedule with two-step timing (initial within 100 hours after a date, then 300‑hour intervals) until modification (Compliance 1).","A judgemental standard—‘‘excessive elongation’’—that requires licensed maintenance personnel to decide whether to modify or replace before further flight (Compliance 2).","Reliance on an external service bulletin (Gulfstream American AG‑CAT SB No. 75 Revision A) for technical procedure, adding dependency on another document (Document).","Reference to an FAA AD for related guidance (Note) which can require cross‑checking across regulatory instruments.","Operational impact: inspections until modification create ongoing administrative and resource burdens (Compliance 1)."],"plain_english_summary":"Owners/operators of Schweizer (Grumman) G‑164B/C/D aeroplanes must inspect aileron bellcrank assemblies for cable‑attachment elongation (initial within 100 hours after 31 Aug 1982, then every 300 hours until modified) and modify or replace any bellcrank showing “excessive elongation” before further flight. Costs fall to the aircraft owner; licensed maintenance personnel judge elongation. The directive enforces recurring checks and repairs to reduce in‑flight cable‑attachment failure risk."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification","history":"/api/acts/ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification/history","analysis":"/api/acts/ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification/analysis","conflicts":"/api/acts/ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification/important-cases","documents":"/api/acts/ad-g164-18-amdt-1-aileron-bellcrank-inspection-and-modification/documents"}}