{"id":"F2006B08015","name":"Airworthiness Directives 2004 - Revocation and Remaking - Ryan ST Series Aeroplanes","slug":"airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115080,"registerId":"commonwealth-F2006B08015-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"Airworthiness Directives 2004 - Revocation and Remaking - Ryan ST Series Aeroplanes","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 20.2\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\n Airworthiness Directives 2004\n\n I, DAVID ALAN VILLIERS, delegate of the Civil Aviation Safety\n\n Authority, acting under subregulation 39.001 (1) of the Civil\n\n Aviation Safety Regulations 1998:\n\n (a) revoke the Airworthiness Directives mentioned in\n\n Schedule 1; and\n\n (b) make, as separate instruments, each Airworthiness\n\n Directive mentioned in Schedule 1 and attached.\n\n \n\n ![](image.001.png)\n\n David Villiers\n\n Delegate of the Civil Aviation Safety Authority\n\n \n\n  20 December 2004\n\n Note:   Each attached Airworthiness Directive is being re-made in exactly the\n\n same form as appears in the latest published edition of the Directive.\n\n \n\n\n Schedule 1 Revocation and Remaking of\n\n Airworthiness Directives\n\n Ryan ST Series Aeroplanes\n\n AD Name AD Number\n\n Lower Flying Wire Lug - Replacement AD/RYAN/1 B\n\n Seat Restraint Installations - Modifications AD/RYAN/2\n\n Front Fin Spar Attachment AD/RYAN/3\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument revokes and re-issues the listed Airworthiness Directives in exactly the same form as the latest published editions (Note). There is no textual indication in the supplied instrument that the substantive scope or technical requirements of those ADs have changed; the action is an administrative re-issuance as separate instruments (opening paragraph and Note; Schedule 1)."},"complexity_factors":["Legal cross-reference to Civil Aviation Safety Regulations 1998 subregulation 39.001(1) (delegated authority element)","Administrative action (revocation and re-making) rather than substantive technical change","Multiple separate instruments (three ADs) to be re-issued","Technical content of the ADs not included in the provided text (requires consultation of the attached ADs for full compliance details)","Stakeholder effects concentrated on a specific aircraft type (owners/operators and maintenance providers)"],"plain_english_summary":"This instrument revokes three existing Airworthiness Directives (ADs) that apply to Ryan ST series aeroplanes and re-issues each of them as separate legal instruments in the same form they already appear in the latest published edition.\n\nWhat the instrument does (mechanically)\n\n- It is a delegated decision by David Alan Villiers under subregulation 39.001(1) of the Civil Aviation Safety Regulations 1998 to revoke the ADs listed in Schedule 1 and to re-make each one as a separate instrument (see opening paragraph and instruction to revoke and make) (subreg 39.001(1)).\n- It records that each re-made AD is identical to the version that appears in the latest published edition of the Directive (see Note: \"Each attached Airworthiness Directive is being re-made in exactly the same form as appears in the latest published edition of the Directive\").\n- Schedule 1 lists the three affected ADs for Ryan ST series aeroplanes: Lower Flying Wire Lug - Replacement (AD/RYAN/1 B); Seat Restraint Installations - Modifications (AD/RYAN/2); Front Fin Spar Attachment (AD/RYAN/3) (see Schedule 1).\n\nWho is affected\n\n- Owners and operators of Ryan ST series aeroplanes, because the listed ADs apply to those aircraft (Schedule 1).\n- Maintenance organisations and engineers who carry out the work required by those ADs, because the ADs specify mandatory maintenance or modification actions.\n- The regulator (Civil Aviation Safety Authority) and its delegate who make and publish ADs (opening paragraph citing subreg 39.001(1)).\n\nWhy it matters (stated purpose and practical effect)\n\n- The stated action is administrative: revoke the existing instrument references and re-issue each AD as a separate, standalone instrument while keeping their substantive content unchanged (opening paragraph and Note).\n- Practically, the re-making preserves the operative requirements that those ADs impose (replacement, modifications, attachment checks) while changing how they are recorded and published as instruments.\n\nCosts, incentives and implementation trade-offs (source-grounded)\n\n- Who pays: The operative costs of compliance (parts, labour, downtime) fall on aircraft owners/operators and maintenance providers who must follow the re-made ADs when they apply (Schedule 1; the instrument makes the ADs into enforceable instruments). \n- Administrative cost and opportunity cost: Re-making the ADs as separate instruments imposes an administrative task on the regulator and possibly on recipients who track instrument citations; the text states the re-made ADs are identical, so the action appears to be administrative rather than substantive (Note).\n- Compliance burden: The instrument does not change substantive obligations but preserves them; therefore, any existing compliance burden remains unchanged. The instrument itself does not add new technical requirements (Note; Schedule 1).\n- Bureaucratic discretion: A delegate of the Civil Aviation Safety Authority exercises the authority to revoke and re-make ADs under subregulation 39.001(1), demonstrating delegated decision-making power to alter the form and publication of AD instruments (opening paragraph citing subreg 39.001(1)).\n- Implementation risk: Because the Note confirms the re-made ADs are identical to the published versions, the primary implementation risk is administrative (ensuring correct re-issuance and publication), not a substantive change to aircraft obligations (Note).\n\nEffects on private choice, markets, and operations\n\n- The action keeps in force the same mandatory technical requirements for affected Ryan ST aeroplanes; private operators retain the same choices about whether and how to comply, subject to the mandatory nature of ADs (Schedule 1; Note).\n- The re-issuance as separate instruments may improve clarity of legal citation or record-keeping, which can reduce transaction costs for operators or maintenance providers who reference ADs; the instrument itself does not state this as a purpose but the effect follows from changing how instruments are presented (mechanical effect of revoking and re-making).\n- There is no change in ownership, competition, pricing or contract freedom described in the text; any impacts on those areas would flow from the substance of the ADs themselves, which are unchanged by this instrument (Note; Schedule 1).\n\nKey source citations\n\n- Delegation and legal basis: the delegate acts under subregulation 39.001(1) of the Civil Aviation Safety Regulations 1998 (opening paragraph).\n- Action taken: revoke the ADs in Schedule 1 and make each as a separate instrument (opening paragraph).\n- Substance unchanged: Note stating each re-made AD is in exactly the same form as the latest published edition.\n- Affected items: Schedule 1 listing AD/RYAN/1 B; AD/RYAN/2; AD/RYAN/3.\n"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This instrument maintains identical scope to the original directives. The explicit note states each directive is 're-made in exactly the same form as appears in the latest published edition.' This is purely an administrative housekeeping exercise to refresh legal authority, not an expansion of regulatory scope."},"complexity_factors":["Very short instrument (under 300 words)","Only 3 substantive items in Schedule 1","No defined terms section — relies on external understanding of 'Airworthiness Directive' and 'Ryan ST Series'","Simple binary structure: (a) revoke, (b) make","No nested exceptions or conditional logic","Cross-references only to Civil Aviation Safety Regulations 1998 (single, clear delegation power)","The actual technical requirements are contained in attached documents not reproduced here"],"plain_english_summary":"This is a technical aviation safety instrument issued by the Civil Aviation Safety Authority (CASA) in December 2004. It does two things:\n\n**What it does:**\n- **Revokes** (cancels) three old Airworthiness Directives for Ryan ST Series aeroplanes\n- **Remakes** those same three directives as brand new, separate legal instruments\n\n**Who it affects:**\n- Owners and operators of **Ryan ST Series aeroplanes** (these are vintage aircraft originally built in the 1930s-1940s)\n- Anyone responsible for maintaining these specific aircraft\n\n**The three safety rules being refreshed:**\n1. **AD/RYAN/1 B** — Requires replacement of lower flying wire lugs (parts that connect wing wires to the fuselage)\n2. **AD/RYAN/2** — Requires modifications to seat restraint installations (seatbelts/harnesses)\n3. **AD/RYAN/3** — Addresses front fin spar attachment (structural connection at the tail)\n\n**Why it matters:**\nAirworthiness Directives are legally binding safety orders. When CASA \"remakes\" directives like this, they're essentially refreshing the legal authority of old safety rules without changing the actual safety requirements. This ensures the rules remain technically valid and enforceable under current law. For aircraft owners, nothing changes in practice — the same safety requirements continue to apply.\n\nThe note at the bottom confirms: each directive is being re-made in exactly the same form as before, so the actual safety standards haven't been altered."}},"importantCases":[],"_links":{"self":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes","history":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes/history","analysis":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes/analysis","conflicts":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes/conflicts","importantCases":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes/important-cases","documents":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-ryan-st-series-aeroplanes/documents"}}