{"id":"F2006B04790","name":"AD/BN-2/77 Amdt 1 - Access Panel Bolts","slug":"ad-bn-2-77-amdt-1-access-panel-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44574,"registerId":"commonwealth-F2006B04790-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BN-2/77 Amdt 1 - Access Panel Bolts","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Safety Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BN-2/77 and issues the following AD under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nPilatus Britten-Norman BN-2 Series Aeroplanes\n\nAD/BN-2/77\n\nAmdt 1\n\n  \nAccess Panel Bolts 11/2003\n\nApplicability: All BN2, BN2A, BN2B, BN2T, BN2T-4R, and BN2T-4S series Islander aircraft. Requirement: Inspect in accordance with action 6.1, 6.2, and 6.3 of B-N Group Mandatory Service\n\nBulletin SB 291, dated 1 May 2003.\n\nAn appropriate bolt approved by Type Certificate holder may replace the A113-1D bolts listed in Service Bulletin SB 291 dated 1 May 2003.\n\nCompliance: For action 6.1: At the next daily check after 4 June 2003, unless already accomplished.\n\nFor action 6.2 and 6.3: At the latest by the next major maintenance inspection. This Amendment becomes effective on 30 October 2003.\n\nBackground: The manufacturer received a report of an aileron travel restriction due to incorrect length bolts installed in left and right access panels at W.STA 181.68, adjacent to the aileron bellcrank levers.\n\nThis amendment approves the use of alternative bolts approved by the Type Certificate holder to replace the A113-1D bolts listed in the Service Bulletin.\n\nThe original issue of this Airworthiness Directive became effective on 4 June 2003.\n\n![](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 10 September 2003\n\n![](image.001.png)\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 8 October 2003.\n\n  \n\nPage 1 of 1","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment modifies the original AD by approving alternative replacement bolts in addition to the A113‑1D bolts specified in SB 291. Source text: 'An appropriate bolt approved by Type Certificate holder may replace the A113‑1D bolts listed in Service Bulletin SB 291 dated 1 May 2003.' The change widens acceptable parts (who may supply replacement bolts) while keeping the inspection requirements tied to SB 291 (Requirement: 'Inspect in accordance with action 6.1, 6.2, and 6.3 of B‑N Group Mandatory Service Bulletin SB 291, dated 1 May 2003'). The original AD became effective 4 June 2003; this Amendment is effective 30 October 2003."},"complexity_factors":["Dependence on an external document: compliance requires following actions 6.1–6.3 of B‑N Group Mandatory Service Bulletin SB 291 (1 May 2003).","Parts-approval discretion: allows alternative bolts only if approved by the Type Certificate holder, introducing third‑party approval (Requirement: 'An appropriate bolt approved by Type Certificate holder may replace the A113‑1D bolts').","Mixed compliance timing: different actions have different deadlines (action 6.1 at next daily check after 4 June 2003; actions 6.2/6.3 by next major maintenance inspection), requiring tracing of maintenance cycles.","Wide applicability: covers all listed BN‑2 series variants, increasing the number of affected operators and maintenance organisations.","Amendment to prior AD: revokes and replaces an earlier AD (original effective 4 June 2003), so operators must check whether earlier work satisfies the new requirements."],"plain_english_summary":"This Airworthiness Directive requires inspection of access-panel bolts on all Pilatus Britten‑Norman BN‑2 Islander variants per actions 6.1–6.3 of Service Bulletin SB 291 (1 May 2003), and allows replacing the listed A113‑1D bolts with any bolt approved by the Type Certificate holder. It applies to all BN2/BN2A/BN2B/BN2T/BN2T‑4R/BN2T‑4S aircraft and sets specific timing for the inspections (next daily check for action 6.1; next major maintenance for 6.2/6.3)."},"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":2,"scope_assessment":{"changed":false,"description":"This amendment stays tightly within the original scope of the AD. The only change is expanding the permitted bolt types from a single specified part (A113-1D) to include alternatives approved by the Type Certificate holder. This is a minor technical relaxation, not a scope expansion."},"complexity_factors":["Single-page document with straightforward structure (Applicability, Requirement, Compliance, Background)","Only 6 defined/model references (aircraft variants and bolt specification)","No nested legislative cross-references — only references to a Service Bulletin (SB 291) and the enabling regulation (CASR 1998, subregulation 39.1(1))","Simple conditional logic: two compliance deadlines based on inspection type","Minimal exceptions: one alternative approval pathway for bolt replacement"],"plain_english_summary":"This AD replaces an earlier order and mandates inspections of access‑panel bolts on Pilatus Britten‑Norman BN‑2 Islander series aircraft after a reported case where incorrect bolt length impeded aileron movement. It affects owners, operators and maintenance personnel and allows using either the original A113‑1D bolts or any bolt approved by the Type Certificate holder. Checks are required promptly (next daily/major maintenance as specified)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bn-2-77-amdt-1-access-panel-bolts","history":"/api/acts/ad-bn-2-77-amdt-1-access-panel-bolts/history","analysis":"/api/acts/ad-bn-2-77-amdt-1-access-panel-bolts/analysis","conflicts":"/api/acts/ad-bn-2-77-amdt-1-access-panel-bolts/conflicts","importantCases":"/api/acts/ad-bn-2-77-amdt-1-access-panel-bolts/important-cases","documents":"/api/acts/ad-bn-2-77-amdt-1-access-panel-bolts/documents"}}