{"id":"F2006B04742","name":"AD/BN-2/30 - Six Degree Droop Flap Micro-Switch Setting - Inspection","slug":"ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44506,"registerId":"commonwealth-F2006B04742-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BN-2/30 - Six Degree Droop Flap Micro-Switch Setting - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Pilatus Britten-Norman BN-2 Series Aeroplanes\n\n \n\nAD/BN-2/30 Six Degree Droop Flap Micro-Switch\n\nSetting - Inspection Applicability: All models with drooped flaps (Modification NB/M/430). Document:               Britten Norman SB No. BN-2/SB.66.\n\nCompliance: Within the next 100 hours time in service after 28 February 1974.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n\n2/74\n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument, as provided, sets a targeted inspection requirement for BN‑2 series aeroplanes fitted with Modification NB/M/430 and specifies the compliance timing and the service bulletin to follow. There is no indication in the supplied text that the scope departs from that original, targeted purpose (Applicability; Document; Compliance)."},"complexity_factors":["Narrow technical scope (single component: six‑degree droop‑flap micro‑switch) (Applicability).","Single mandatory action (inspection) with a fixed compliance window (100 hours after 28 Feb 1974) (Compliance).","Dependency on an external technical reference (Britten Norman SB No. BN‑2/SB.66) for procedural detail (Document).","Requires qualified maintenance personnel and access to maintenance records to establish hours‑in‑service timing (Compliance).","Concentrated affected population (only BN‑2 models with Modification NB/M/430), reducing regulatory breadth but increasing concentration of compliance burden (Applicability)."],"plain_english_summary":"This AD mandates that BN‑2 series aircraft fitted with Modification NB/M/430 have the six‑degree droop‑flap micro‑switch setting inspected per Britten Norman SB No. BN‑2/SB.66 within 100 hours time‑in‑service after 28 February 1974. Operators bear the inspection and any corrective costs; work must be done by qualified maintenance personnel to maintain regulatory compliance."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive targeting a specific technical defect in a specific aircraft modification. It has not expanded beyond its original narrow safety purpose."},"complexity_factors":["Extremely short document — approximately 150 words total","Only one substantive requirement (inspect/adjust micro-switch)","Single applicability criterion (Modification NB/M/430)","One external reference only (manufacturer's Service Bulletin BN-2/SB.66)","Simple compliance deadline (100 hours time in service after fixed date)","No defined terms section, no conditional logic, no nested exceptions","Standardised regulatory format but minimal substantive content"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific maintenance action on certain aircraft.\n\n**What it does:**\nOrders owners and operators of **Pilatus Britten-Norman BN-2 series aircraft** (small twin-engine planes commonly used for regional transport and island hopping) to inspect and adjust a specific component — the **micro-switch that controls the six-degree droop flap setting**.\n\n**Who it affects:**\n- All BN-2 models fitted with \"drooped flaps\" (a specific wing modification designated NB/M/430)\n- Aircraft operators, maintenance engineers, and owners\n\n**Why it matters:**\nFlaps are the hinged surfaces on the back of wings that extend during takeoff and landing to create more lift at slow speeds. The \"droop\" setting (partially extended) is critical for safe low-speed handling. If the micro-switch that controls this setting is incorrectly positioned, the pilot may not get the expected flap position — potentially leading to loss of control during critical flight phases.\n\n**What must be done:**\n- Inspect and correct the micro-switch setting as specified in **Britten-Norman Service Bulletin BN-2/SB.66**\n- Complete this work **within the next 100 flight hours after 28 February 1974**\n\n**Key point:** This directive has long since passed its compliance deadline (1974), but remains part of the regulatory record for historical aircraft still in service."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection","history":"/api/acts/ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection/history","analysis":"/api/acts/ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection/analysis","conflicts":"/api/acts/ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection/conflicts","importantCases":"/api/acts/ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection/important-cases","documents":"/api/acts/ad-bn-2-30-six-degree-droop-flap-micro-switch-setting-inspection/documents"}}