{"id":"F2006B10072","name":"AD/G159/28 - Wing Lower Surface - Inspection","slug":"ad-g159-28-wing-lower-surface-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55517,"registerId":"commonwealth-F2006B10072-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G159/28 - Wing Lower Surface - Inspection","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 ORDERS CIVIL AVIATION SAFETY AUTHORITY                            PART 105 SCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  GULFSTREAM (GRUMMAN) G.159 SERIES AEROPLANES\n\n \n\nAD/G159/28 Wing Lower Surface - Inspection 7/76\n\nApplicability: All models.\n\n \n\nDocument: Grumman Customer Bulletin No. 283.\n\n \n\nCompliance: Before 1 November 1976 and thereafter at intervals not exceeding 3 years.\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The supplied text is a single airworthiness directive requiring wing lower surface inspection for all G.159 models and does not indicate any change to the instrument's scope from a prior version. The directive specifies applicability, references the manufacturer bulletin for technical procedure, and gives an initial deadline plus a recurring interval; no evidence in the supplied text shows the scope has been altered from an earlier intent."},"complexity_factors":["Narrow, simple mandate (single inspection requirement) with a clear recurring interval (\"Compliance: ... intervals not exceeding 3 years\").","Applicability covers all models, so scope is broad across the fleet (\"Applicability: All models.\").","Technical detail and acceptance criteria are omitted from the AD and delegated to an external document (\"Document: Grumman Customer Bulletin No. 283\"), increasing dependence on that bulletin.","No enforcement, exemption, or alternative compliance language present in the supplied text, leaving implementation and compliance proof arrangements unspecified.","Fixed initial compliance deadline (before 1 November 1976) plus recurring timing creates scheduling and record‑keeping needs for operators."],"plain_english_summary":"This AD mandates that all Gulfstream (Grumman) G.159 aircraft have the wing lower surface inspected per Grumman Customer Bulletin No. 283, with the first inspection before 1 November 1976 and repeated at intervals not exceeding three years. Owners/operators must arrange and fund the inspections; the AD delegates technical procedures and acceptance criteria to the manufacturer’s bulletin."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1976 addressing a specific inspection requirement. It has not expanded beyond its original purpose of ensuring wing lower surface integrity through periodic inspection. The scope remains precisely as intended: a targeted safety mandate for one aircraft type regarding one structural component."},"complexity_factors":["Extremely short document — only 4 substantive lines of operational content","Zero defined terms requiring interpretation","No cross-references to other legislation or regulations","Simple conditional structure: single applicability clause ('All models'), single compliance deadline with straightforward recurring interval","No exceptions, exemptions, or nested conditions","References external technical document (Grumman Customer Bulletin No. 283) but does not incorporate its content — compliance achieved by following that document"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order — issued by Australia's Civil Aviation Safety Authority for **Gulfstream G.159 series aircraft** (also known as Grumman G.159s). \n\n**What it requires:**\n- **Inspection of the wing lower surface** on all models of this aircraft type\n- **When:** First inspection must be completed before 1 November 1976, then repeated **every 3 years** thereafter\n\n**Why it matters:**\nAirworthiness Directives are legally binding safety instructions. Aircraft owners and operators **must** comply or the aircraft cannot fly legally. This particular directive addresses potential structural issues with the wing lower surface — a critical component for flight safety. The reference to \"Grumman Customer Bulletin No. 283\" suggests this was triggered by the manufacturer identifying a defect or wear pattern that needed systematic monitoring.\n\n**Who it affects:**\n- Owners and operators of Gulfstream (Grumman) G.159 aircraft in Australia\n- Maintenance organisations servicing these aircraft\n\nThe 3-year recurring interval indicates this is an ongoing airworthiness concern requiring regular monitoring rather than a one-off fix."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g159-28-wing-lower-surface-inspection","history":"/api/acts/ad-g159-28-wing-lower-surface-inspection/history","analysis":"/api/acts/ad-g159-28-wing-lower-surface-inspection/analysis","conflicts":"/api/acts/ad-g159-28-wing-lower-surface-inspection/conflicts","importantCases":"/api/acts/ad-g159-28-wing-lower-surface-inspection/important-cases","documents":"/api/acts/ad-g159-28-wing-lower-surface-inspection/documents"}}