{"id":"F2007L04519","name":"AD/BAe 146/129 - Undercarriage Main Beam Sidestay Bolts at Frame 29","slug":"ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":70985,"registerId":"commonwealth-F2007L04519-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"British Aerospace BAe 146 Series Aeropla","sectionType":"division","heading":"British Aerospace BAe 146 Series Aeroplanes","content":"### British Aerospace BAe 146 Series Aeroplanes\n\n| AD/BAe 146/129 | Undercarriage Main BeamSidestay Bolts at Frame 29 | 13/2007 |\n| -------------- | ------------------------------------------------- | ------- |\n\n| Applicability: | All Model BAe 146 and AVRO 146-RJ series aircraft, all serial numbers.                                                                                                                                                                                       |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | Action in accordance with the requirements of EASA AD 2007-0277.Note: BAE Systems (Operations) Inspection Service Bulletin ISB 53-194 original issue, or later EASA approved revision, refers.                                                               |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of20 December 2007.                                                                                                                                                                  |\n|                | This Airworthiness Directive becomes effective on 20 December 2007.                                                                                                                                                                                          |\n| Background:    | During inspection of undercarriage main beam sidestays, bolts attaching the undercarriage main beam sidestay to frame 29 were found with sheared bolt heads. Undetected sheared or loose bolts could result in the possible collapse of a main landing gear. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n8 November 2007","sortOrder":0},{"sectionNumber":"AD/BAe 146/129","sectionType":"part","heading":"AD/BAe 146/129","content":"## AD/BAe 146/129","sortOrder":1},{"sectionNumber":"Undercarriage Main BeamSidestay Bolts at","sectionType":"part","heading":"Undercarriage Main BeamSidestay Bolts at Frame 29","content":"## Undercarriage Main Beam  \nSidestay Bolts at Frame 29","sortOrder":2},{"sectionNumber":"13/2007","sectionType":"part","heading":"13/2007","content":"## 13/2007","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"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 (approximately 200 words)","Only 1 defined term implicitly referenced (the EASA AD number)","Single, clear requirement: comply with external technical document","No nested exceptions or conditional logic","Straightforward applicability (all models, all serial numbers)","Single compliance date with no alternative methods or phased implementation"],"plain_english_summary":"This mandatory Airworthiness Directive orders owners and operators of all BAe 146 and AVRO 146‑RJ aircraft to inspect and, if necessary, replace the bolts securing the main undercarriage beam after reports of sheared bolt heads. It enforces compliance with EASA AD 2007‑0277 and BAE Systems ISB 53‑194 (effective 20 Dec 2007) to prevent landing‑gear collapse."},"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":false,"description":"This Directive adopts the requirements of EASA AD 2007-0277 and refers to BAE ISB 53-194; it does not expand the technical scope beyond that external AD. The only domestic modification in the text is the specified effective date (20 December 2007)."},"complexity_factors":["Cross-reference to an external mandatory document (EASA AD 2007-0277) — requires users to consult another instrument for operative detail.","Dependence on a manufacturer inspection service bulletin (BAE ISB 53-194) or later EASA-approved revision for technical procedures.","Safety-critical maintenance action (landing-gear attachment bolts) that can ground aircraft and create operational downtime.","Universal applicability to all serial numbers of the listed types increases reach and aggregate compliance burden.","Fixed effective date (20 December 2007) imposes a clear compliance timeline rather than a phased rollout."],"plain_english_summary":"This Directive requires owners/operators of all BAe 146 and AVRO 146‑RJ aircraft to inspect and, if needed, repair or replace the undercarriage main beam sidestay bolts at frame 29, following the steps in EASA AD 2007‑0277 (and BAE ISB 53‑194). It targets every serial-numbered aircraft of those types; operators bear the inspection and repair costs. The stated purpose is to prevent undetected sheared or loose bolts that could lead to main landing gear collapse."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29","history":"/api/acts/ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29/history","analysis":"/api/acts/ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29/analysis","conflicts":"/api/acts/ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29/conflicts","importantCases":"/api/acts/ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29/important-cases","documents":"/api/acts/ad-bae-146-129-undercarriage-main-beam-sidestay-bolts-at-frame-29/documents"}}