{"id":"F2006B07005","name":"AD/SF340/75 - Bolt and Bushing Installation at WS 123.38","slug":"ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48638,"registerId":"commonwealth-F2006B07005-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 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 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.","sortOrder":0},{"sectionNumber":"AD/SF340/75 Bolt and Bushing Installatio","sectionType":"part","heading":"AD/SF340/75 Bolt and Bushing Installation at WS 123.38 3/2000","content":"# AD/SF340/75 Bolt and Bushing Installation at WS 123.38 3/2000\n\nApplicability: Model SF340A, serial numbers 004 through 159, and Model 340B, serial numbers 160 through 459; with flap assembly and serial numbers listed below:\n\n\\- 7257800-507, serial numbers 1258 through 1270.\n\n\\- 7257800-508, serial numbers 1257 through 1269.\n\nRequirement: Action in accordance with SAAB Aircraft Mandatory Service Bulletin (SB) 340-57- 035, dated 18 January 2000.\n\nNote: LFV AD 1-152 refers.\n\nCompliance: Identification and initial inspection to be accomplished within 800 hours time in service after 23 March 2000. Inspect thereafter at intervals not to exceed 800 hours time in service.\n\nReplacement to be accomplished within 4800 hours time in service after 23 March 2000.\n\nThis Airworthiness Directive becomes effective on 23 March 2000.\n\nBackground: Some discrepancies have been found in the bolt and bushing installation at WS\n\n123.38. The most likely cause was at implementation of SB 340-57-027. Bushings of incorrect length may have been installed at the forward attachment point to the triangular fitting. Bolts and bushings may also have been installed at the aft attachment point. As a consequence, high bearing stresses may lead to worn bushings, elongated holes, vibrations and cracked flap fittings.\n\n![Signature of Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority](image.003.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 10 February 2000\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 23 February 2000.","sortOrder":1}],"analysis":{"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 Airworthiness Directive maintains its original narrow scope. It addresses a specific unsafe condition in specific aircraft serial numbers and part numbers, exactly as intended when the regulatory framework for ADs was established. There is no scope creep or expansion beyond the original technical safety purpose."},"complexity_factors":["Single, specific technical requirement referencing an external service bulletin (SAAB SB 340-57-035)","Limited applicability: only 2 aircraft models with specific serial number ranges and 2 specific part numbers","Clear, unambiguous compliance timeline (800 hours / 4800 hours)","No nested exceptions, conditional logic, or extensive cross-referencing to other legislation","Straightforward background explanation of the safety risk","Single delegated decision-maker with clear signature authority"],"plain_english_summary":"This CASA safety order requires owners/operators of Saab 340A/B (s/n 004–459) with certain flap assembly parts to inspect and correct wrong-sized bolts and bushings that cause excessive wear and cracking. Inspections are required every 800 flight hours and incorrect fittings must be replaced within 4,800 flight hours of 23 March 2000. Compliance is mandatory because faulty flap fittings can lead to flap failure and unsafe landings."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD is narrowly focused on correcting a specific installation error (incorrect bolts/bushings) at WS 123.38 on a limited set of SAAB SF340 aircraft and associated flap assemblies. It does not broaden beyond that safety purpose: it prescribes inspections and replacement on a fixed schedule and refers to a single SAAB service bulletin for technical steps. There is no expansion of scope beyond the original corrective intent described in the Background."},"complexity_factors":["Short document length (one-page AD)","Clear, narrow applicability: two model ranges with specific serial-number ranges and two flap part numbers","Single external procedure referenced (SAAB SB 340-57-035) — AD defers technical detail to that SB","Two time-based compliance limits (initial/recurring inspections at 800 hours; replacement by 4,800 hours)","One cross-reference to a foreign AD (LFV AD 1-152)","No extensive defined-term section, few conditional branches or nested exceptions","Enforcement basis cited (subreg 39.1(1) CAR 1998) but no complex penalty or administrative regime in the text"],"plain_english_summary":"**What this Airworthiness Directive (AD) does**\n\n- Requires certain SAAB SF340A and 340B aircraft to be inspected and, if necessary, have parts replaced because of incorrect bolt/bushing work found at a particular wing station (WS 123.38). (Applicability; Requirement; Background)\n\n**Which aircraft are affected**\n\n- Model SF340A, serial numbers 004–159.\n- Model SF340B, serial numbers 160–459.\n- Only aircraft that have the specific flap assemblies listed (part numbers 7257800-507 and 7257800-508) with the serial numbers shown (1257–1270, depending on the part). (Applicability)\n\n**What operators must do**\n\n- Follow the technical steps in SAAB Mandatory Service Bulletin SB 340-57-035 (dated 18 Jan 2000). The AD makes that SB the required method for inspection/rectification; the AD does not itself set out the step-by-step maintenance work. (Requirement)\n- Identify affected flap assemblies and carry out an initial inspection within 800 hours time in service after 23 March 2000, and repeat inspections at intervals not exceeding 800 hours. (Compliance)\n- Replace affected items where necessary; replacement must be completed within 4,800 hours time in service after 23 March 2000. (Compliance)\n\n**Why this rule was issued (stated reason)**\n\n- During or after implementation of an earlier service bulletin (SB 340-57-027), bushings of incorrect length and/or incorrect bolt/bushing installations may have been fitted at the forward and aft attachment points of a triangular flap fitting at WS 123.38. That can create high bearing stresses leading to worn bushings, elongated holes, vibration, and cracked flap fittings. The AD is intended to correct that unsafe condition. (Background)\n\n**Who pays and who decides**\n\n- Aircraft owners/operators pay for inspections, parts, and labour, and for any aircraft downtime while work is done. Maintenance organisations (approved maintenance providers or SAAB-authorised shops) will normally carry out the work following the SAAB SB. (Requirement; Compliance)\n- The Civil Aviation Safety Authority (CASA), via its delegate, issued the AD under subregulation 39.1(1) of the Civil Aviation Regulations 1998; CASA enforces compliance. (Opening paragraph)\n\n**Practical effects and implementation considerations**\n\n- Operational impact: operators must add inspections to maintenance schedules every 800 hours and plan for a mandatory replacement by 4,800 hours — this is a recurring inspection obligation until replacement is done. (Compliance)\n- Compliance depends on access to the SAAB service bulletin, availability of correct replacement bushings/bolts, and competent maintenance personnel to perform and certify the work. (Requirement)\n- Recordkeeping: operators must identify serial numbers of flap assemblies and keep proof of inspections/replacements to demonstrate compliance to CASA inspectors. (Applicability; Compliance)\n- Market effects: the AD increases demand for the specified parts and for approved maintenance work on affected SF340s; independent maintenance organisations can perform the work subject to certification standards. Costs are concentrated on owners/operators of the small set of affected aircraft; safety benefits are general and diffuse. (Applicability; Requirement)\n\n**Risk, trade-offs and compliance burden**\n\n- The AD trades the direct costs of inspections, parts and downtime against the safety risk of structural damage leading to in‑flight vibration or cracked fittings. (Background; Compliance)\n- Implementation risks include delays if parts are scarce, errors in identifying affected serial-numbered flap assemblies, or inconsistent interpretation of the SAAB service bulletin; these create potential for non‑compliance or repeated inspections. (Requirement)\n\n**Cross references**\n\n- The AD refers to SAAB SB 340-57-035 for the technical procedure and notes an LFV (Swedish authority) AD 1-152 as related information. Operators should consult the SAAB SB and any relevant foreign ADs for full context. (Requirement; Note)\n\n(Sections cited: \"Applicability\", \"Requirement\", \"Compliance\", \"Background\", and the issuing authority reference to subregulation 39.1(1) of CAR 1998.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38","history":"/api/acts/ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38/history","analysis":"/api/acts/ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38/analysis","conflicts":"/api/acts/ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38/conflicts","importantCases":"/api/acts/ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38/important-cases","documents":"/api/acts/ad-sf340-75-bolt-and-bushing-installation-at-ws-123-38/documents"}}