{"id":"F2010L01441","name":"AD/HS 125/89 Amdt 3 - Elevator Mass Balance Side Plate and Spigot","slug":"ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":83969,"registerId":"commonwealth-F2010L01441-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"British Aerospace BAe 125 Series Aeropla","sectionType":"division","heading":"British Aerospace BAe 125 Series Aeroplanes","content":"### British Aerospace BAe 125 Series Aeroplanes\n\n| AD/HS 125/89 Amdt 3 | Elevator Mass Balance Side Plate and Spigot | 11/2010 |\n| ------------------- | ------------------------------------------- | ------- |\n\n| Applicability: | All models up to and including BAe 125-800B series. |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | Action in accordance with FAA AD 89-18-07 R1, amendment 39-10878, effective18 December 1998. |\n| Compliance: | Unless already accomplished, before further flight after 21 June 2010. |\n| | This Amendment becomes effective on 7 June 2010. |\n| Background: | This AD was originally raised in 1987. Corrosion had been reported on the elevator mass balance side plate assembly and the balance weight spigot. If not corrected, such corrosion may result in displacement of the side plate leading to control surface interference. Amendment 1 clarified the inspection periodicity.Amendment 2 introduced the requirements of the State of design AD and increased the applicability to include the 800 series aircraft. Note that the FAA AD does not formally quote the on-going maintenance schedule inspection period as did Amendment 1 to this AD. The maintenance schedules of the applicable aircraft series contain the on-going structural inspection requirements (each 2 years) for the elevator mass balance side plates, spigots and installation.Amendment 3 changes the compliance date and the effective date to ensure there is an adequate period between the two dates. |\n\n![](image.001.png)\n\nMike Higgins \nDelegate of the Civil Aviation Safety Authority\n\n24 May 2010","sortOrder":0},{"sectionNumber":"AD/HS 125/89 Amdt 3","sectionType":"part","heading":"AD/HS 125/89 Amdt 3","content":"## AD/HS 125/89 Amdt 3","sortOrder":1},{"sectionNumber":"Elevator Mass Balance Side Plate and Spi","sectionType":"part","heading":"Elevator Mass Balance Side Plate and Spigot","content":"## Elevator Mass Balance Side Plate and Spigot","sortOrder":2},{"sectionNumber":"11/2010","sectionType":"part","heading":"11/2010","content":"## 11/2010","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Yes. The AD’s scope was expanded and administratively adjusted: Amendment 2 extended applicability to include the BAe 125-800B series and incorporated the State‑of‑design FAA AD requirements (Background; Requirement). Amendment 3 altered the effective and compliance dates to allow an adequate period between notification and required action (Background; Compliance)."},"complexity_factors":["Cross-reference to an external FAA AD (Requirement) — requires users to consult another document for technical actions and standards.","Multiple amendments altering obligations and dates (Background) — Amendment 1 clarified periodicity; Amendment 2 expanded applicability; Amendment 3 changed compliance/effective dates.","Applicability across a range of models including -800B series (Applicability) — widens affected operator base.","Fixed compliance deadline tied to effective date (Compliance) — short compliance window increases operational scheduling pressure.","Interaction with existing maintenance schedules (Background) — ongoing two‑year inspections are referenced, creating overlap between AD and operator maintenance planning.","Safety risk hinging on corrosion detection and repair (Background) — inspection quality and repair decisions affect operational safety and costs."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of British Aerospace BAe 125 aeroplanes (all models up to and including -800B) to inspect and, if necessary, repair the elevator mass-balance side plate and weight spigot in accordance with FAA AD 89-18-07 R1. CASA set compliance to be completed before further flight after 21 June 2010 (Amendment effective 7 June 2010). The directive responds to reported corrosion that could displace the side plate and interfere with control surfaces. Operators pay for inspections and repairs; the AD relies on existing two‑year structural inspection cycles. "},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment represents a minor administrative adjustment to compliance dates only. The substantive safety scope — addressing corrosion on elevator mass balance components — has remained consistent since the original 1987 directive. While Amendment 2 expanded applicability to include the 800 series, this was a deliberate expansion of coverage rather than scope creep. Amendment 3 makes no changes to the technical requirements, affected components, or aircraft models covered."},"complexity_factors":["Very short document (approximately 300 words)","Only 2 substantive requirements: applicability and compliance deadline","Single cross-reference to external FAA directive (AD 89-18-07 R1) — the actual technical work is delegated to that document","No defined terms section","No conditional logic or nested exceptions","Straightforward temporal compliance structure (fixed calendar dates)","Background section provides narrative context but does not create legal obligations"],"plain_english_summary":"This AD mandates inspection and repair of corrosion on the elevator mass balance side plates and spigots of British Aerospace BAe 125 series aeroplanes (up to and including 800B) to prevent side-plate movement and potential elevator control interference. It follows FAA AD 89-18-07 R1 procedures, becomes effective 7 June 2010, and must be complied with before further flight after 21 June 2010."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot","history":"/api/acts/ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot/history","analysis":"/api/acts/ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot/analysis","conflicts":"/api/acts/ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot/conflicts","importantCases":"/api/acts/ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot/important-cases","documents":"/api/acts/ad-hs-125-89-amdt-3-elevator-mass-balance-side-plate-and-spigot/documents"}}