{"id":"F2009L03365","name":"AD/G164/5 Amdt 2 - Elevator Torque Tubes - Inspection","slug":"ad-g164-5-amdt-2-elevator-torque-tubes-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":140938,"registerId":"commonwealth-F2009L03365-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Schweizer (Grumman) G-164 (Ag-Cat) Serie","sectionType":"division","heading":"Schweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes","content":"### Schweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes\n\n| AD/G164/5 Amdt 2 | Elevator Torque Tubes - Inspection | 10/2009 |\n| ---------------- | ---------------------------------- | ------- |\n\n| Applicability: | All model G164 and G164A aircraft S/Nos 1 to 461.                                                                                                                                                                                                                                                                                                                                        |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Inspect the left and right hand elevator torque tubes for cracking adjacent to the inboard rib attachment welds, and also where the two 1/8 inch diameter blind rivets attach the right hand elevator leading edge skin cover to the torque tubes. Cracked tubes are to be repaired in accordance with Grumman Ag-Cat Service Bulletin (SB) No. 33.                                      |\n| Compliance:    | At intervals not exceeding 100 hours time in service after 24 September 2009, or from time of compliance with the previous issue of this Directive, which ever occurs first.The repetitive inspections required by this Directive may be discontinued upon installation of the modification kit referenced in Grumman American Service Note No. 23 to modify the elevator horn assembly. |\n|                | This Amendment becomes effective on 24 September 2009.                                                                                                                                                                                                                                                                                                                                   |\n| Background:    | This amendment includes a terminating action.                                                                                                                                                                                                                                                                                                                                            |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n12 August 2009","sortOrder":0},{"sectionNumber":"AD/G164/5 Amdt 2","sectionType":"part","heading":"AD/G164/5 Amdt 2","content":"## AD/G164/5 Amdt 2","sortOrder":1},{"sectionNumber":"Elevator Torque Tubes - Inspection","sectionType":"part","heading":"Elevator Torque Tubes - Inspection","content":"## Elevator Torque Tubes - Inspection","sortOrder":2},{"sectionNumber":"10/2009","sectionType":"part","heading":"10/2009","content":"## 10/2009","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is Amendment 2 to an existing Airworthiness Directive. The amendment adds a terminating action (modification kit option) to the original inspection requirement, but does not expand the scope beyond the original safety purpose of addressing elevator torque tube cracking in G-164 aircraft. The scope remains tightly focused on the specific airworthiness issue."},"complexity_factors":["Single, clearly defined applicability (specific aircraft models and serial numbers)","Straightforward inspection requirement with two specific locations identified","Simple compliance schedule (100-hour intervals with clear start date)","Single terminating action clearly referenced","No nested definitions, cross-references to other legislation, or conditional exceptions","Total length is approximately 200 words of substantive content"],"plain_english_summary":"This CASA Airworthiness Directive affects owners/operators of Schweizer (Grumman) G‑164 and G‑164A \"Ag‑Cat\" aircraft serials 1–461, requiring repetitive inspections of elevator torque tubes for cracks at welded joints and the right elevator leading‑edge rivet area every 100 flight hours (from 24 Sep 2009). Cracks must be repaired per Grumman Service Bulletin No. 33; installing the modification kit in Grumman Service Note No. 23 terminates the inspection requirement. The AD prevents loss of pitch control and possible crashes."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment adds a terminating action: repetitive inspections (100‑hour intervals) may be discontinued upon installation of the modification kit referenced in Grumman American Service Note No. 23. It also specifies the effective date (24 September 2009) and ties compliance to prior Directive compliance where applicable (Compliance; Background)."},"complexity_factors":["Targeted applicability to specific serial numbers (G164/G164A S/N 1–461) reduces scope but requires fleet-specific tracking (Applicability).","Repetitive inspection interval of 100 hours TIS creates ongoing operational and maintenance burden (Compliance).","Repairs must follow an external document (Grumman Ag‑Cat SB No. 33), creating dependency on manufacturer service instructions (Requirement).","Existence of a terminating action via a modification kit (Grumman Service Note No. 23) adds an alternative compliance path but requires parts/installation resources (Compliance, Background).","Effective date and rollover clause (‘after 24 September 2009, or from time of compliance with the previous issue’) requires reconciling prior compliance history (Compliance)."],"plain_english_summary":"This directive requires owners/operators of Schweizer (Grumman) G‑164 and G‑164A aircraft S/N 1–461 to inspect left and right elevator torque tubes for cracking adjacent to inboard rib welds and at rivet attachment points, and to repair any cracks per Grumman Ag‑Cat Service Bulletin No. 33 (Requirement, Applicability). Inspections must be repeated every 100 hours TIS from 24 September 2009 (or from prior compliance) but may be discontinued if the modification kit in Grumman American Service Note No. 23 is installed (Compliance, Background). Operators pay inspection, repair and modification costs and bear related downtime."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-g164-5-amdt-2-elevator-torque-tubes-inspection","history":"/api/acts/ad-g164-5-amdt-2-elevator-torque-tubes-inspection/history","analysis":"/api/acts/ad-g164-5-amdt-2-elevator-torque-tubes-inspection/analysis","conflicts":"/api/acts/ad-g164-5-amdt-2-elevator-torque-tubes-inspection/conflicts","importantCases":"/api/acts/ad-g164-5-amdt-2-elevator-torque-tubes-inspection/important-cases","documents":"/api/acts/ad-g164-5-amdt-2-elevator-torque-tubes-inspection/documents"}}