{"id":"F2008L00771","name":"AD/AMD 50/45 - Wing Primary Structure","slug":"ad-amd-50-45-wing-primary-structure","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72830,"registerId":"commonwealth-F2008L00771-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AMD Falcon 50 and 900 Series Aeroplanes","sectionType":"division","heading":"AMD Falcon 50 and 900 Series Aeroplanes","content":"### AMD Falcon 50 and 900 Series Aeroplanes\n\n| AD/AMD 50/45 | Wing Primary Structure | 4/2008 |\n| ------------ | ---------------------- | ------ |\n\n| Applicability: | Model Falcon 50 aircraft, all serial numbers.                                                                                                                                                                                                                                                                                                                                                                                                                                                                |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | Perform Maintenance Procedure MP 57-401 Non-Destructive Test inspection of the wing lower panels stiffeners between ribs 13 and 17.Note 1: Maintenance Procedure MP 57-401 is introduced through Temporary Change 74 of the Mystere-Falcon Aircraft Maintenance Manual.Note 2: EASA AD 2008-0021 refers.                                                                                                                                                                                                     |\n| Compliance:    | Upon the accumulation of 14,200 flight cycles since new. Repeat thereafter at intervals not to exceed 5,350 flight cycles.                                                                                                                                                                                                                                                                                                                                                                                   |\n|                | This Airworthiness Directive becomes effective on 10 April 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| Background:    | An analysis of in-service events revealed that corrosion of wing fuel tank pressure relief valves was likely to occur well before reaching the overhaul time. This situation could result in valves stuck in the closed position. There is the possibility that some aircraft could have experienced wing overpressure with the latent failure of both valve units. An overpressure, although not sufficient to cause static damage, could have impaired the fatigue damage tolerance of the wing structure. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n26 February 2008","sortOrder":0},{"sectionNumber":"AD/AMD 50/45","sectionType":"part","heading":"AD/AMD 50/45","content":"## AD/AMD 50/45","sortOrder":1},{"sectionNumber":"Wing Primary Structure","sectionType":"part","heading":"Wing Primary Structure","content":"## Wing Primary Structure","sortOrder":2},{"sectionNumber":"4/2008","sectionType":"part","heading":"4/2008","content":"## 4/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text does not indicate a change of scope from any prior requirement. It applies to all Falcon 50 aircraft (Applicability) and targets a specific structural area (wing lower panel stiffeners between ribs 13 and 17) in response to the overpressure/corrosion risk described in the Background. The directive clarifies method (MP 57‑401) and timing (Compliance) rather than expanding or narrowing applicability."},"complexity_factors":["Single technical NDT mandate (Requirement) — requires specific inspection technique (MP 57‑401) making the task technical but narrowly focused.","Numeric thresholds and intervals (Compliance) — clear trigger (14,200 flight cycles) and repeat interval (5,350 cycles) create straightforward but non‑flexible compliance scheduling.","External document dependence (Requirement Notes 1–2) — MP 57‑401 is introduced by Temporary Change 74 and the AD cross‑references EASA AD 2008‑0021, requiring access to and interpretation of other documents.","Universal applicability (Applicability) — covers all Falcon 50 serial numbers, so fleet operators must apply uniformly.","Enforcement and timing (Compliance) — effective date fixed (10 April 2008), so operators must plan around a set regulatory start point.","Operational burden (Requirement, Compliance) — inspections impose direct costs (labour, downtime, NDT capability) on operators and require maintenance scheduling.","Limited regulatory discretion in text — directive prescribes procedure and intervals rather than offering alternative compliance routes, which concentrates decision points on operators (Requirement, Compliance)."],"plain_english_summary":"This Airworthiness Directive requires operators of Falcon 50 aircraft to carry out non‑destructive testing (NDT) of the wing lower panel stiffeners between ribs 13 and 17 using Maintenance Procedure MP 57‑401 (via Temporary Change 74). Inspections are due at 14,200 flight cycles since new and must be repeated every 5,350 cycles.\n\nThe directive says the inspections respond to a risk of structural impairment after possible wing overpressure caused by corroded fuel‑tank relief valves; operators pay the inspection and scheduling costs and must meet the stated intervals (Requirement, Compliance, Background)."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific technical issue (wing structural integrity following potential overpressure events). The scope remains precisely limited to the identified safety risk and the specified aircraft model. There is no evidence of scope creep or expansion beyond the original safety purpose."},"complexity_factors":["Single, specific technical requirement (one inspection procedure)","Clear, unambiguous compliance timeline (14,200 cycles initially, then 5,350 cycle intervals)","Narrow applicability (only Falcon 50 aircraft, all serial numbers)","No nested exceptions or conditional logic","Only 2 brief notes referencing external technical documents","Total length is approximately 200 words","No defined terms section or interpretation provisions"],"plain_english_summary":"This AD requires owners/operators of Falcon 50 jets to perform a mandatory non‑destructive inspection of lower wing stiffeners between ribs 13–17, looking for hidden fatigue damage. First inspection at 14,200 flight cycles, then every 5,350 cycles thereafter.\n\nIt's prompted by fuel tank pressure‑relief valve corrosion that can trap pressure and silently weaken the wing’s fatigue tolerance—undetected damage could lead to structural failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-amd-50-45-wing-primary-structure","history":"/api/acts/ad-amd-50-45-wing-primary-structure/history","analysis":"/api/acts/ad-amd-50-45-wing-primary-structure/analysis","conflicts":"/api/acts/ad-amd-50-45-wing-primary-structure/conflicts","importantCases":"/api/acts/ad-amd-50-45-wing-primary-structure/important-cases","documents":"/api/acts/ad-amd-50-45-wing-primary-structure/documents"}}