{"id":"F2006B09361","name":"AD/ECUREUIL/55 Amdt 1 - MGB Suspension Bi-Directional Cross Beam","slug":"ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53622,"registerId":"commonwealth-F2006B09361-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ECUREUIL/55 Amdt 1 - MGB Suspension Bi-Directional Cross Beam","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)  \nEurocopter AS 350 (Ecureuil) Series Helicopters\n\nAD/ECUREUIL/55\n\nAmdt 1\n\n  \nMGB Suspension Bi-Directional Cross Beam 9/97\n\nApplicability: Model AS 350, versions B, BA, B1, B2, and D, fitted with MGB suspension bi- directional cross beam P/N 350A38.1018, all dash numbers, on the complete cross beam assemblies P/N 350A38.0210, all dash numbers without Mod No. 072720 embodied.\n\nRequirement: Action in accordance with EUROCOPTER FRANCE SB No 05.00.28.\n\nNote: DGAC AD 96-156-071(B)R1 refers.\n\nCompliance: Within 30 hours time in service after 4 September 1996; as applicable. Thereafter as specified in the requirement document.\n\nThe initial issue of this directive had effect from 4 September 1996 and the compliance remains unchanged. This amendment has effect from 14 August 1997.\n\nBackground: The manufacturer received an in-service report of a crack in the MGB suspension cross beam.\n\nAmendment 1 alters the Applicability to remove certain modified assemblies, and reference the manufacturer’s definitive Service Bulletin.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment narrowed the original scope by excluding helicopters with Mod No. 072720 already embodied. This reduced the number of affected aircraft, making the directive more targeted rather than broader."},"complexity_factors":["Highly specific technical applicability criteria (5 model versions, 2 part numbers with 'all dash numbers', specific modification exclusions)","References external technical documents (Eurocopter Service Bulletin 05.00.28 and French DGAC AD 96-156-071(B)R1) without reproducing their content","Dual effective dates (initial issue 4 September 1996, amendment 14 August 1997) with unchanged compliance deadline","Aviation-specific terminology requiring domain knowledge (MGB = Main Gearbox, P/N = Part Number, TIS = Time in Service, SB = Service Bulletin, DGAC = French aviation authority)"],"plain_english_summary":"This AD requires owners/operators of certain Eurocopter AS350 (B/BA/B1/B2/D) helicopters fitted with specific MGB suspension bi‑directional cross beam part numbers to carry out the Eurocopter France service bulletin inspections/repairs, to detect and fix cracks found in that critical structural member. It excludes aircraft already modified by Mod No. 072720. The action prevents possible catastrophic failure of the main gearbox support."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 1 narrows the directive’s scope by altering the Applicability to remove certain modified assemblies (those with Mod No. 072720 embodied are excluded) and by referencing the manufacturer’s definitive Service Bulletin; the compliance timing (within 30 hours after 4 September 1996) remains unchanged."},"complexity_factors":["Technical specificity of affected parts (exact P/Ns for cross beam and assemblies) requiring accurate parts/records checks","Exclusion based on embodiment of Mod No. 072720 — requires verification of modification status in maintenance histories","Dependence on an external manufacturer document (EUROCOPTER FRANCE SB No 05.00.28) for the substantive work instructions","Short mandated compliance window (30 hours time in service) creating operational and scheduling pressure","Retroactive effect from 4 September 1996 and ongoing recurring requirements “thereafter as specified” in the SB","Regulatory amendment that changed applicability (removal of certain modified assemblies) requiring operators to re-assess affected fleet"],"plain_english_summary":"This airworthiness directive requires owners/operators of Eurocopter AS350 (B/BA/B1/B2/D) helicopters fitted with specific MGB suspension cross‑beam parts to follow the manufacturer’s Service Bulletin (EUROCOPTER FRANCE SB No 05.00.28) and complete the required inspection/rectification within 30 flight hours after 4 September 1996. The rule responds to an in‑service crack report; aircraft with Mod No. 072720 already embodied are excluded. Operators pay for and schedule the work; the Civil Aviation Safety Authority enforces compliance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam","history":"/api/acts/ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam/history","analysis":"/api/acts/ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam/analysis","conflicts":"/api/acts/ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam/conflicts","importantCases":"/api/acts/ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam/important-cases","documents":"/api/acts/ad-ecureuil-55-amdt-1-mgb-suspension-bi-directional-cross-beam/documents"}}