{"id":"F2006L04100","name":"AD/S-92/2 - Main Gearbox Lubrication Pump Vespel Spline Adapters","slug":"ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":61030,"registerId":"commonwealth-F2006L04100-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Sikorsky S-92 Series Helicopters","sectionType":"division","heading":"Sikorsky S-92 Series Helicopters","content":"### Sikorsky S-92 Series Helicopters\n\n| AD/S-92/2 | Main Gearbox Lubrication PumpVespel Spline Adapters | 2/2007 TX |\n| --------- | --------------------------------------------------- | --------- |\n\n| Applicability: | Sikorsky Model S-92A helicopters with main gearbox (MGB) lubrication/scavenge pump, part number (P/N) 92351-15800-101, with vespel spline adapter, P/N 1584000-1, installed.                                                                                                                                                                                                                                                                                                                                                                            |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Remove and replace each MGB lubrication/scavenge pump vespel spline adapter in accordance with paragraph 3.A., steps (1) through (6) of the Accomplishment Instructions in Sikorsky Aircraft Corporation Alert Service Bulletin No. 92-63-001, dated 1 April 2005.Note: FAA AD 2005-12-03 Amdt 39-14119 dated 1 June 2005 refers.                                                                                                                                                                                                                       |\n| Compliance:    | Before further flight, unless accomplished previously, and thereafter, at intervals not to exceed 50 hours time-in-service.                                                                                                                                                                                                                                                                                                                                                                                                                             |\n|                | This Airworthiness Directive becomes effective on 18 December 2006.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |\n| Background:    | This AD requires replacing the MGB lubrication/scavenge pump vespel spline adapters before further flight, and thereafter, replacing them at certain intervals. This is prompted by a reported incident of an in-flight loss of oil pressure. The actions specified in this AD are intended to prevent loss of lubrication to the MGB, which could cause failure of one or both engine input drives, or planetary gear to sun gear tooth mesh failure, resulting in loss of power to the rotor system and subsequent loss of control of the helicopter. |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n13 December 2006","sortOrder":0},{"sectionNumber":"AD/S-92/2","sectionType":"part","heading":"AD/S-92/2","content":"## AD/S-92/2","sortOrder":1},{"sectionNumber":"Main Gearbox Lubrication PumpVespel Spli","sectionType":"part","heading":"Main Gearbox Lubrication PumpVespel Spline Adapters","content":"## Main Gearbox Lubrication Pump  \nVespel Spline Adapters","sortOrder":2},{"sectionNumber":"2/2007 TX","sectionType":"part","heading":"2/2007 TX","content":"## 2/2007 TX","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope aligns with the instrument's stated intent: limited to S‑92A helicopters with the specified MGB pump and vespel spline adapter, requiring immediate replacement and recurrent replacement at ≤50 hours to mitigate reported in‑flight oil pressure loss risk (Applicability; Requirement; Compliance; Background). No extension or narrowing beyond those elements is introduced in the text."},"complexity_factors":["Narrow, part-specific applicability requiring identification of pump and adapter P/Ns (Applicability).","Prescriptive mandatory action to follow manufacturer ASB steps 3.A.(1)-(6), tying compliance to a non‑statutory document (Requirement).","Short recurring compliance interval (every 50 hours TIS) increases operational and maintenance scheduling burden (Compliance).","Immediate grounding risk until replacement is done (\"before further flight\"), creating potential downtime and logistic strain (Compliance).","Safety-critical consequence motivates strict enforcement but does not create discretionary relief within the AD text (Background; Requirement).","Reference to FAA AD and manufacturer documents creates cross-jurisdictional compliance and record-keeping implications (Requirement; Background)."],"plain_english_summary":"Requires operators of Sikorsky S‑92A helicopters fitted with MGB pump P/N 92351‑15800‑101 and vespel spline adapter P/N 1584000‑1 to remove and replace the adapter per Sikorsky Alert Service Bulletin 92‑63‑001 (steps 3.A.(1)–(6)). Must be done before next flight and repeated every 50 flight hours. Stated purpose is to prevent loss of MGB lubrication and resulting drive or gear failure. Operators pay for parts, labour and downtime; the regulator enforces timing. (Applicability; Requirement; Compliance; Background)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive targeting a specific safety-critical component failure. The scope remains tightly focused on the original safety issue (vespel spline adapter failure causing oil pressure loss) with no expansion beyond the specific part and helicopter model identified."},"complexity_factors":["Single, specific technical requirement with clear part numbers","Only one compliance condition (before further flight, then every 50 hours)","No defined terms section or interpretation provisions","No nested exceptions or conditional logic","Short document (approximately 200 words of substantive content)","Single cross-reference to FAA AD and manufacturer service bulletin for technical procedure"],"plain_english_summary":"This CASA Airworthiness Directive mandates immediate and recurring replacement of a specific vespel spline adapter in the main gearbox lubrication pump on affected Sikorsky S‑92A helicopters (pump PN 92351‑15800‑101, adapter PN 1584000‑1). \n\nIt affects operators of those S‑92A helicopters because the adapter has failed in flight, causing oil‑pressure loss and risking main gearbox seizure, loss of rotor drive and possible crash; replacements must be done before flight and every 50 flight hours."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters","history":"/api/acts/ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters/history","analysis":"/api/acts/ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters/analysis","conflicts":"/api/acts/ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters/conflicts","importantCases":"/api/acts/ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters/important-cases","documents":"/api/acts/ad-s-92-2-main-gearbox-lubrication-pump-vespel-spline-adapters/documents"}}