{"id":"F2006B10119","name":"AD/G21/5 - Fuel Tank Baffles - Inspection","slug":"ad-g21-5-fuel-tank-baffles-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55655,"registerId":"commonwealth-F2006B10119-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G21/5 - Fuel Tank Baffles - Inspection","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)  \nGrumman G21 (Goose) Series Aeroplanes\n\nAD/G21/5 Fuel Tank Baffles \\- Inspection 10/77\n\nApplicability: All model G21A with S/Nos. B-34, B-35, B-38 to B-42, B-45 to B-51, B-53, B-54, B- 55, B-57 to B-61, B-63, B-64, B-65, B-67, B-68, B-70 to B-71, B-74, B-76, B-77, B-\n\n82, B-83, B-85 to B-90, B-92, B-96 to B-99, B-101, B-106, B-107, B-111, B-116, B-\n\n118, B-119, B-120, B-124, B-125, B-127 to B-134, B-137 to B-141, B-143, B-144\n\nand B-145.\n\nRequirement: 1\\. Inspect the fuel tank baffles at wing STAs 42, 54 and 75 through the hand holds in bottom of integral fuel tanks. If baffles are riveted to stiffeners no further action is required.\n\n    2. If baffle stiffeners are attached by spot welds reinspect as per repetitive inspection compliance.\n\n    3. Replace any cracked baffles with riveted baffles.\n\nNote 1. Replacement of spotwelded baffles with riveted baffles is termination action for inspection.\n\nNote 2. FAA AD 49-16-1 refers.\n\nCompliance: 1. Before issue of Certificate of Airworthiness.\n\n2. Reinspect spot welded baffles at intervals not exceeding 100 hours time in service.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Based on the text provided, the directive applies only to the listed G21A serial numbers and prescribes inspection, reinspection interval, and replacement actions. There is no indication in this instrument that its scope has been altered from its original stated applicability or requirements."},"complexity_factors":["Narrow applicability limited to a detailed list of G21A serial numbers (Applicability) — increases administrative tracking for operators.","Specific inspection locations: wing STAs 42, 54 and 75 and access method via bottom hand holds (Requirement 1) — creates defined physical access/inspection constraints.","Binary structural test: riveted vs spot‑welded attachment determines inspection/repair path (Requirement 1–3) — requires judgement by maintenance personnel.","Repetitive inspection interval for spot‑welded baffles: every 100 hours time in service (Requirement 2; Compliance 2) — imposes recurring operational downtime and recordkeeping.","Replacement of cracked baffles with riveted units is terminating action (Requirement 3; Note 1) — creates a one‑time capital/parts cost but ends ongoing inspections.","Must be complied with before issue of Certificate of Airworthiness (Compliance 1) — can delay entry to service.","Cross‑reference to FAA AD 49‑16‑1 (Note 2) — potential for harmonised technical expectations or additional materials.","Low regulatory discretion: actions are prescriptive (inspect, reinspect interval, replace) but inspection findings require technician judgement (inspectors decide rivet vs spot weld/crack)."],"plain_english_summary":"This airworthiness directive requires inspection of fuel‑tank baffles on specified Grumman G21A serial numbers at wing stations 42, 54 and 75 through handholds in the tank floor. If baffles are riveted to stiffeners no further action is needed; if attached by spot welds they must be reinspected every 100 hours and cracked baffles replaced with riveted baffles (replacement ends the inspection requirement). It affects aircraft owners/operators and maintenance organisations responsible for inspections, repairs and Certificates of Airworthiness."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive for a specific maintenance issue on a specific aircraft type. It has not expanded beyond its original purpose of ensuring fuel tank baffle integrity on Grumman G21 aircraft."},"complexity_factors":["Very short document (approximately 200 words)","Only 3 main requirements with clear conditional logic (if riveted → stop; if spot-welded → repeat; if cracked → replace)","Single defined term (\"STA\" for station, a standard aviation measurement)","No cross-references to other legislation (only a reference to a related FAA directive in a note)","Specific but limited applicability (one aircraft model, specific serial numbers listed exhaustively)","Clear compliance deadlines with no nested exceptions"],"plain_english_summary":"This directive requires owners/operators of listed Grumman G21 “Goose” amphibians to inspect fuel-tank baffles through hand-hold openings at three wing stations before issuing a Certificate of Airworthiness. If baffles are riveted no further action is needed; if spot-welded they must be re‑inspected every 100 flight hours and ultimately replaced with riveted baffles; cracked baffles must be replaced immediately. It affects the roughly 70 specified serial-number aircraft to prevent fuel movement hazards that can compromise flight safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g21-5-fuel-tank-baffles-inspection","history":"/api/acts/ad-g21-5-fuel-tank-baffles-inspection/history","analysis":"/api/acts/ad-g21-5-fuel-tank-baffles-inspection/analysis","conflicts":"/api/acts/ad-g21-5-fuel-tank-baffles-inspection/conflicts","importantCases":"/api/acts/ad-g21-5-fuel-tank-baffles-inspection/important-cases","documents":"/api/acts/ad-g21-5-fuel-tank-baffles-inspection/documents"}}