{"id":"F2006B02053","name":"AD/AA-5/20 - Alternate Static Selector Valve - Inspection","slug":"ad-aa-5-20-alternate-static-selector-valve-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41275,"registerId":"commonwealth-F2006B02053-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AA-5/20 - Alternate Static Selector Valve - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue NK,Aircraft below 5700 kg,Gulfstream (Grumman American/ American Aviation) AA-5 Series Aeroplanes,Alternate Static Selector Valve - Inspection,20\ntitle: Airworthiness Directive - AD/AA-5/20 - Alternate Static Selector Valve - Inspection\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)  Gulfstream (Grumman American/ American Aviation) AA-5 Series Aeroplanes\n\n \n\nAD/AA-5/20 Alternate Static Selector Valve - Inspection NK\n\nApplicability: Aeroplanes S/Nos. AA5A-0001 to AA5A-0340 and AA5B-0001 to AA5B-0451. Also all aeroplanes modified by the addition of Gerdes A-1390 alternate static valve shipped from Grumman prior to 19 March 1977.\n\n \n\nDocument: 1. Grumman American SB 160; or\n\n \n\n2. FAA AD 77-08-03.\n\n \n\nCompliance: Within 100 hours’ time in service after 31 May 1977.\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":false,"description":"This is a discrete, time-bound safety directive targeting a specific mechanical defect in a specific aircraft model. It has not expanded beyond its original purpose of mandating inspection of the alternate static selector valve."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined applicability criteria (serial number ranges and specific modification)","Single compliance action required (inspection)","Only 2 reference documents cited","No nested conditions, exceptions, or cross-references to other legislation","Clear deadline (100 hours time in service after fixed date)"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspection of the alternate static selector valve on specified Grumman American/Gulfstream AA‑5 series aircraft (serials AA5A‑0001–AA5A‑0340, AA5B‑0001–AA5B‑0450, and any with a Gerdes A‑1390 valve shipped before 19 Mar 1977). Inspections must be done within 100 flight hours after 31 May 1977 to prevent faulty static readings that can produce dangerous altitude/airspeed errors; compliance follows Grumman Service Bulletin 160 or FAA AD 77‑08‑03."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive does not expand or narrow scope beyond its stated applicability. It applies only to AA‑5 series aeroplanes with the listed serial numbers and to aeroplanes fitted with a Gerdes A‑1390 valve shipped from Grumman prior to 19 March 1977, and it requires a one‑time inspection per Grumman SB 160 or FAA AD 77‑08‑03 within the specified 100‑hour window after 31 May 1977."},"complexity_factors":["Narrow, explicit applicability by serial‑number ranges and a defined modification (Gerdes A‑1390 shipped before 19 March 1977) reduces operational scope.","Mandates compliance by reference to external technical documents (Grumman SB 160 or FAA AD 77‑08‑03), creating dependency on those documents for procedural detail.","Fixed compliance window tied to a historical date (within 100 hours’ time in service after 31 May 1977) requires calculation of flight hours from a set date.","No ongoing monitoring or recurrent inspections specified, so procedural complexity is limited to a single action."],"plain_english_summary":"This Airworthiness Directive requires a one-time inspection of the alternate static selector valve on specific Gulfstream (Grumman American) AA‑5 series aeroplanes (serial numbers AA5A‑0001 to AA5A‑0340 and AA5B‑0001 to AA5B‑0451) and any aeroplane fitted with a Gerdes A‑1390 valve shipped from Grumman before 19 March 1977. Operators must carry out the inspection using Grumman SB 160 or FAA AD 77‑08‑03 within 100 hours’ time in service after 31 May 1977; compliance costs and actions fall to the aircraft owners/operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-aa-5-20-alternate-static-selector-valve-inspection","history":"/api/acts/ad-aa-5-20-alternate-static-selector-valve-inspection/history","analysis":"/api/acts/ad-aa-5-20-alternate-static-selector-valve-inspection/analysis","conflicts":"/api/acts/ad-aa-5-20-alternate-static-selector-valve-inspection/conflicts","importantCases":"/api/acts/ad-aa-5-20-alternate-static-selector-valve-inspection/important-cases","documents":"/api/acts/ad-aa-5-20-alternate-static-selector-valve-inspection/documents"}}