{"id":"F2006B01800","name":"AD/A109/16 Amdt 3 - Main Rotor Blades","slug":"ad-a109-16-amdt-3-main-rotor-blades","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":40998,"registerId":"commonwealth-F2006B01800-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A109/16 Amdt 3 - Main Rotor Blades","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)  \nAgusta A109 Series Helicopters\n\nAD/A109/16\n\nAmdt 3\n\n  \n\nMain Rotor Blades 12/90 DM\n\nApplicability: All models fitted with main rotor blades P/N 109-0103-01-( ) (all dash numbers), serial numbers 378 through to 1519 inclusive, which have achieved 300 or more hours component time in service.\n\nRequirement: Action in accordance with Agusta Bollettino Tecnico No 109-79, dated 27 July 1990\\. The radiographic inspection should be performed using X-rays of energy no greater than 50 KVp to obtain the required contrast sensitivity, in the area of interest, of no greater than 1%.\n\nNote 1: This Bollettino Tecnico supersedes B T No 109-6, Revs A and B. Eddy current inspections performed in accordance with previous issues of this AD (B T No 109-6) shall be accepted as meeting the eddy current inspection requirement of this amendment.\n\nNote 2: Approval to perform the radiographic inspection in accordance with Part 2 of the Requirement document and Agusta Report No 109-02-79, issued 15 July 1990, may be granted upon application to the Authority. Applicants will need access to suitable radiographic equipment and must be able to demonstrate 1% or better contrast sensitivity on a representative specimen.\n\nCompliance: For Part 1 of the Requirement document: At intervals not to exceed 25 hours time in service and before further flight upon the occurrence of anomalous vibratory conditions, until such time as Part 2 of the Requirement Document has been accomplished.\n\nFor Part 2 of the Requirement document: At operator’s option.\n\nBackground: Several cases of main rotor blade cracking have been found in service, including one which failed catastrophically. Fatigue cracking has been initiated by chordwise scoring, introduced during manufacture, adjacent to spar mass balance weights.\n\nAmendment 2 reduced the initial inspection threshold to 600 hours.\n\nAmendment 3 further reduces the initial inspection threshold to 300 hours, in accordance with the manufacturer’s recommendations, and also introduces a once only inspection procedure to positively identify blades which have unacceptable levels of scoring. Such blades must be removed from service before further flight. Any positive indications, whether confirmed or otherwise, resulting from these inspections, should be the subject of a Major Defect Report.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 3 narrows the inspection threshold and expands inspection procedures compared with earlier versions: it reduces the initial inspection threshold to 300 hours (previously reduced to 600 hours by Amendment 2) and introduces a once‑only radiographic procedure to positively identify and require removal of blades with unacceptable scoring. It also formalises acceptance of prior eddy‑current inspections and provides an approval pathway for radiographic inspection (see Background; Amendment 2; Amendment 3; Requirement; Notes 1–2; Compliance)."},"complexity_factors":["Technical inspection specification: radiography limited to ≤50 KVp and 1% contrast sensitivity (Requirement).","Applicability tied to specific part number and a serial‑number range (Applicability).","Time‑based and event‑based compliance: repeated Part 1 intervals (≤25 hours) and before‑flight checks after anomalous vibration, plus optional Part 2 at operator’s choice (Compliance).","Treatment of legacy inspections: acceptance of prior eddy‑current inspections as satisfying the eddy‑current requirement (Note 1).","Approval route and evidentiary requirement for alternate radiographic performance (Note 2 requires application to the Authority and demonstration of 1% contrast).","Mandatory removal from service for blades with unacceptable scoring and reporting requirement for positive indications (Background/Amendment 3).","Amendment history changing thresholds and inspection scope (Background), requiring operators to track revision history and compliance timing."],"plain_english_summary":"This airworthiness directive requires operators of Agusta A109 helicopters fitted with specified main rotor blades (P/N 109-0103-01-( ), S/N 378–1519) that have reached 300 or more component hours to carry out inspections per Agusta Bollettino Tecnico No 109‑79, including a specified radiographic check (X‑rays ≤50 KVp, 1% contrast). It accepts earlier eddy‑current inspections and lets operators elect to do the Part 2 inspection; the aim is to detect manufacturing scoring that can start fatigue cracking and remove unsafe blades before flight."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"The original directive (implied by Amendment 2 reference) applied to blades with 600+ hours. Amendment 3 significantly expands the safety net by lowering the threshold to 300 hours, capturing more blades earlier in their service life. It also adds a new one-off inspection procedure (Part 2) that wasn't in previous versions, effectively broadening the scope from ongoing periodic inspections to include a specific identification sweep for defective blades."},"complexity_factors":["Multiple compliance pathways (Part 1 vs Part 2) with different timing requirements","Technical specifications requiring specialist knowledge (50 KVp X-ray energy, 1% contrast sensitivity, eddy current testing)","Cross-reference to external manufacturer documents (Agusta Bollettino Tecnico No 109-79, Agusta Report No 109-02-79) that are not reproduced in the text","Serial number and part number ranges requiring careful matching","Conditional logic: different actions required based on vibration anomalies, flight hours accumulated, and inspection results","Nested approval process for alternative inspection methods (application to Authority required)"],"plain_english_summary":"This AD requires owners/operators of Agusta A109 helicopters fitted with certain main rotor blades (P/Ns 109‑0103‑01, S/Ns 378–1519) to begin inspections once blades reach 300 flight hours, and to repeat them every 25 hours (or immediately if unusual vibration occurs) using eddy‑current or low‑energy X‑ray methods. A one‑off detailed inspection targets blades with manufacturing scoring; blades found unacceptable must be removed from service.\n\nThe AD also mandates reporting any positive findings as Major Defect Reports. It lowers the inspection threshold from 600 to 300 hours."}},"importantCases":[],"_links":{"self":"/api/acts/ad-a109-16-amdt-3-main-rotor-blades","history":"/api/acts/ad-a109-16-amdt-3-main-rotor-blades/history","analysis":"/api/acts/ad-a109-16-amdt-3-main-rotor-blades/analysis","conflicts":"/api/acts/ad-a109-16-amdt-3-main-rotor-blades/conflicts","importantCases":"/api/acts/ad-a109-16-amdt-3-main-rotor-blades/important-cases","documents":"/api/acts/ad-a109-16-amdt-3-main-rotor-blades/documents"}}