{"id":"F2008L02966","name":"AD/OH-58/2 - Pylon Support Link Assemblies","slug":"ad-oh-58-2-pylon-support-link-assemblies","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":74933,"registerId":"commonwealth-F2008L02966-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell OH-58A (206A-1) Series Helicopters","sectionType":"division","heading":"Bell OH-58A (206A-1) Series Helicopters","content":"### Bell OH-58A (206A-1) Series Helicopters\n\n| AD/OH-58/2 | Pylon Support Link Assemblies | 9/2008 |\n| ---------- | ----------------------------- | ------ |\n\n| Applicability: | Model OH-58A (Bell 206A-1) series helicopters, including all certificated versions, with pylon support links part number 206-031-508-5 or -7, installed.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | 1. Inspect the pylon support link assemblies in accordance with Part II of Bell Helicopter Service Bulletin No. 206-01-73-2 Revision A, or later FAA approved revision.If the bearing inner race measures more than 1.255-inches in diameter or there is any crack in the link, before further flight, replace the link assembly.2. Inspect the pylon support link assemblies in accordance with Part III of Bell Helicopter Service Bulletin No. 206-01-73-2 Revision A, or later FAA approved revision.If cracking is detected during any inspection, before further flight, replace the link assembly.Installation of pylon support links part number 206-031-589 constitutes terminating action to the requirements of this Directive.Note: FAA AD 73-08-03 Amdt 39-1622 refers. |\n| Compliance:    | 1. Unless already accomplished, within 10 hours time in service after the effective date of this Directive.2. Initially, within 25 hours time in service after compliance with Requirement 1, and thereafter at intervals not to exceed 25 hours time in service.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n|                | This Airworthiness Directive becomes effective on 28 August 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n| Background:    | The actions required by this Directive are intended to prevent possible failure of certain pylon support links.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n14 July 2008","sortOrder":0},{"sectionNumber":"AD/OH-58/2","sectionType":"part","heading":"AD/OH-58/2","content":"## AD/OH-58/2","sortOrder":1},{"sectionNumber":"Pylon Support Link Assemblies","sectionType":"part","heading":"Pylon Support Link Assemblies","content":"## Pylon Support Link Assemblies","sortOrder":2},{"sectionNumber":"9/2008","sectionType":"part","heading":"9/2008","content":"## 9/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The Directive addresses a narrowly defined safety issue for a specific part and aircraft model. It does not expand into unrelated systems or additional aircraft types. The inclusion of a terminating action (installing P/N 206-031-589) is consistent with the Directive’s purpose of eliminating the unsafe condition or the need for repeated inspections. There is no indication in the text that the Directive grew beyond its original safety-focused intent."},"complexity_factors":["Short, single-subject directive focused on one component (pylon support links)","Two required inspection actions (Requirement 1 and Requirement 2) plus a terminating action","One numeric acceptance threshold (bearing inner race > 1.255 inches) and a binary crack/no‑crack test","Fixed, short compliance intervals (10 hours for initial; 25 hours initial after Requirement 1 and recurring every 25 hours)","Cross-reference to an external document (Bell Helicopter Service Bulletin No. 206-01-73-2 Revision A or later FAA‑approved revision) which contains procedural detail","Cross-reference to an FAA AD (FAA AD 73-08-03 Amdt 39-1622) which may affect interpretation or history"],"plain_english_summary":"**What this directive does (mechanically)\n\n- Requires operators of Bell OH-58A (Bell 206A-1) series helicopters that have pylon support links with part numbers 206-031-508-5 or 206-031-508-7 installed to inspect those link assemblies.\n- Two specific inspections are mandated (referred to in the directive as Requirement 1 and Requirement 2) and must be carried out following the procedures in Bell Helicopter Service Bulletin No. 206-01-73-2 Revision A (or a later FAA‑approved revision).\n  - Requirement 1 (initial): Measure the bearing inner race and inspect the link for cracks. If the bearing inner race is more than 1.255 inches in diameter or any crack exists, the link assembly must be replaced before further flight.\n  - Requirement 2 (repetitive): Perform the inspection tasks set out in Part III of the service bulletin. If cracking is detected at any inspection, replace the link assembly before further flight.\n- A permanent fix (called a terminating action) is available: installing pylon support links with part number 206-031-589 removes the need for the repetitive inspections required by this Directive.\n\n**Who is affected\n\n- Owners and operators of Bell OH-58A (206A-1) series helicopters that have pylon support links P/N 206-031-508-5 or -7 installed.\n- Maintenance organisations and personnel who perform inspections and parts replacement on those helicopters.\n\n**Compliance timing (how quickly it must be done)\n\n- Requirement 1 (the first inspection): within 10 hours time in service after the Directive’s effective date.\n- Requirement 2 (the initial repetitive inspection): within 25 hours time in service after complying with Requirement 1, and then every 25 hours time in service thereafter.\n- Any required replacement because of oversize inner race or cracking must be done before the next flight.\n\n**Why it matters (stated purpose and practical implications)\n\n- Stated purpose: the directive’s expressed aim is to prevent possible failure of certain pylon support links (that is, to reduce the risk of in‑service link failure).\n\n- Practical effects and trade-offs:\n  - Who pays: Owners/operators pay for inspections, parts and labour. If an affected link must be replaced, the operator bears the cost of the replacement part and the downtime.\n  - Operational impact: Frequent inspections (every 25 flight hours) increase maintenance workload and can reduce available flight hours because aircraft may be grounded until inspections or replacements are completed.\n  - Supply and scheduling risk: If replacement parts (including the terminating part P/N 206-031-589) are limited in supply, operators may experience further delays or higher costs to source parts.\n  - Behavioural change: Operators will either (a) perform frequent inspections and replace links when indicated, or (b) adopt the terminating action (install P/N 206-031-589) to remove the inspection burden. Choosing the terminating action requires up‑front cost and logistics to obtain and fit the new part.\n  - Maintenance market effects: Independent maintenance providers may see increased demand for inspections and replacements; conversely, operators that install the terminating part reduce long‑term recurring maintenance workload.\n\n**Implementation, enforcement and discretion\n\n- The inspections must follow the referenced Bell service bulletin (Revision A or a later FAA‑approved revision). That cross-reference gives maintenance technicians a detailed procedure to follow but also ties compliance to whatever changes appear in later FAA‑approved revisions of the service bulletin.\n- The regulator enforces compliance; non‑compliance can lead to grounding or enforcement action. Maintenance personnel must decide whether a link requires replacement (based on the 1.255‑inch measurement and crack detection language).\n\n**Bottom line (concise)\n\n- This is a targeted airworthiness directive requiring measurement and crack inspections of specific pylon support link assemblies on OH‑58A helicopters, with mandatory replacement if the inner race is oversized or any crack is found, and offering a replace‑to‑terminate option (P/N 206‑031‑589). It shifts inspection and replacement costs and operational downtime onto helicopter owners/operators while providing a one‑time upgrade path to remove the recurring inspection requirement."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive focused on a specific mechanical defect in a specific helicopter model. The scope remains tightly constrained to pylon support link safety inspections and has not expanded beyond its original safety purpose."},"complexity_factors":["Short, single-purpose document (1 page)","Only 2 defined part numbers referenced","Clear sequential requirements with explicit measurements (1.255 inches)","Simple conditional logic: 'If X found, then replace before flight'","Single cross-reference to FAA AD 73-08-03 for context","Terminating action clearly specified (installation of part 206-031-589 ends obligations)"],"plain_english_summary":"This AD mandates inspections of pylon support link assemblies on Bell OH‑58A (206A‑1) helicopters with parts 206‑031‑508‑5 or ‑7: inspect within 10 flight hours for worn bearing inner race (>1.255 in) or cracks, replace before flight if found, and repeat crack inspections every 25 flight hours. It affects owners/operators/maintainers and prevents catastrophic failure; installing part 206‑031‑589 terminates the inspection requirement."}},"importantCases":[],"_links":{"self":"/api/acts/ad-oh-58-2-pylon-support-link-assemblies","history":"/api/acts/ad-oh-58-2-pylon-support-link-assemblies/history","analysis":"/api/acts/ad-oh-58-2-pylon-support-link-assemblies/analysis","conflicts":"/api/acts/ad-oh-58-2-pylon-support-link-assemblies/conflicts","importantCases":"/api/acts/ad-oh-58-2-pylon-support-link-assemblies/important-cases","documents":"/api/acts/ad-oh-58-2-pylon-support-link-assemblies/documents"}}