{"id":"F2008L01522","name":"AD/B767/240 - Horizontal Stabiliser Ballscrew","slug":"ad-b767-240-horizontal-stabiliser-ballscrew","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":119928,"registerId":"commonwealth-F2008L01522-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 767 Series Aeroplanes","sectionType":"division","heading":"Boeing 767 Series Aeroplanes","content":"### Boeing 767 Series Aeroplanes\n\n| AD/B767/240 | Horizontal Stabiliser Ballscrew | 6/2008 |\n| ----------- | ------------------------------- | ------ |\n\n| Applicability: | All Model 767-200, -300, -300F, and -400ER aircraft.                                                                                                                                                                                                                                                                                                                                                                                         |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2008-06-06 Amdt 39-15418.Note: Boeing Service Bulletins 767-27A0194 Revision 2 and 767-27A0195Revision 2, or later FAA approved revisions, refer.                                                                                                                                                                                                                             |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of5 June 2008.                                                                                                                                                                                                                                                                                                                                                       |\n|                | This Airworthiness Directive becomes effective on 5 June 2008.                                                                                                                                                                                                                                                                                                                                                                               |\n| Background:    | The FAA received a report of extensive corrosion of a ballscrew in the drive mechanism of the horizontal stabiliser on a similar aircraft model. An undetected failure of the primary load path for the ballscrew in the drive mechanism of the horizontal stabiliser and subsequent wear and failure of the secondary load path, could lead to loss of control of the horizontal stabiliser and consequent loss of control of the aircraft. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n16 April 2008","sortOrder":0},{"sectionNumber":"AD/B767/240","sectionType":"part","heading":"AD/B767/240","content":"## AD/B767/240","sortOrder":1},{"sectionNumber":"Horizontal Stabiliser Ballscrew","sectionType":"part","heading":"Horizontal Stabiliser Ballscrew","content":"## Horizontal Stabiliser Ballscrew","sortOrder":2},{"sectionNumber":"6/2008","sectionType":"part","heading":"6/2008","content":"## 6/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The instrument aligns domestic requirements with FAA AD 2008-06-06 and the referenced Boeing service bulletins and sets a revised effective date of 5 June 2008. It does not expand applicability beyond the stated Boeing 767 variants or alter the technical actions required in the referenced FAA document."},"complexity_factors":["Cross-reference to FAA AD 2008-06-06 and Boeing Service Bulletins (requires operators to obtain and follow external technical documents).","Applicability across multiple 767 variants (fleet-wide application increases coordination and scheduling complexity).","Safety-critical component (horizontal stabiliser ballscrew): inspection and corrective-action requirements can cause aircraft downtime and parts/repair costs.","Revised effective date (administrative change) requiring operators to update compliance calendars and work instructions.","Regulatory enforcement by CASA — operators must align local maintenance actions with FAA-specified technical steps and any later FAA‑approved revisions.","Risk-driven urgency: failure mode involves both primary and secondary load-path degradation, raising compliance priority and potential for immediate grounding if defects found."],"plain_english_summary":"This Airworthiness Directive requires operators of all Boeing 767‑200, ‑300, ‑300F and ‑400ER aeroplanes to perform the inspections and corrective actions set out in FAA AD 2008‑06‑06 and the referenced Boeing service bulletins for the horizontal stabiliser ballscrew. It is effective 5 June 2008.\n\nCorrosion was reported in a ballscrew and could allow failure of primary and secondary load paths, risking loss of stabiliser control; operators pay for inspections and repairs, and CASA enforces compliance by mandating FAA‑specified technical actions and timelines."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 4 defined structural elements (Applicability, Requirement, Compliance, Background)","Single cross-reference to external FAA document and two Boeing service bulletins","No nested conditional logic or exceptions","Straightforward mandatory action with clear effective date","Technical content is delegated entirely to external aerospace engineering documents"],"plain_english_summary":"This CASA Airworthiness Directive mandates immediate inspection and corrective action on the horizontal stabiliser ballscrew for Boeing 767 (-200, -300, -300F, -400ER) after FAA-reported severe corrosion that could lead to loss of pitch control.\n\nOperators must follow FAA AD 2008-06-06 and two Boeing service bulletins, complying by the deadline tied to 5 June 2008 — affecting all Australian operators of these 767 models."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b767-240-horizontal-stabiliser-ballscrew","history":"/api/acts/ad-b767-240-horizontal-stabiliser-ballscrew/history","analysis":"/api/acts/ad-b767-240-horizontal-stabiliser-ballscrew/analysis","conflicts":"/api/acts/ad-b767-240-horizontal-stabiliser-ballscrew/conflicts","importantCases":"/api/acts/ad-b767-240-horizontal-stabiliser-ballscrew/important-cases","documents":"/api/acts/ad-b767-240-horizontal-stabiliser-ballscrew/documents"}}