{"id":"F2006B06958","name":"AD/SF340/29 Amdt 1 - Lower Drag Strut Assembly","slug":"ad-sf340-29-amdt-1-lower-drag-strut-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114856,"registerId":"commonwealth-F2006B06958-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SF340/29 Amdt 1 - Lower Drag Strut Assembly","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nSAAB SF340 Series Aeroplanes\n\nAD/SF340/29\n\nAmdt 1\n\n  \nLower Drag Strut Assembly 11/91\n\nApplicability: Model SF340A with serial numbers \\-004 through \\-159.\n\nModel 340B with serial numbers \\-160 through \\-166.\n\nRequirement: Action in accordance with the Technical Requirements of Swedish LFV AD 1-049 Revision A.\n\nNote: SAAB-SCANIA AB Service Bulletin SAAB 340-54-027 Revision 1 refers.\n\nCompliance: As specified in the Requirement Document with a revised effective date of\n\n14 November 1991 for Australian registered aircraft. The effective date of the previous issue of this Directive was 8 August 1991.\n\nBackground: Field experience has revealed the bolts and collars attaching the lower drag strut fitting have been losing their torque. The effective date required by the LFV is extended by three months.\n\nAmendment 1 is issued to reflect a revision of the Requirement Document which has a change to the compliance time.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard technical amendment to an Airworthiness Directive. The scope remains exactly as originally intended: addressing a specific mechanical defect in specific aircraft serial numbers. The amendment only adjusts the compliance timeline (extending by three months), not the substantive safety requirement."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 defined applicability criteria (serial number ranges)","Single requirement referencing external technical document","No nested exceptions or conditional logic","Simple amendment structure with one change (extended compliance date)","No cross-references to other legislation beyond the referenced Swedish AD and SAAB Service Bulletin"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for **SAAB SF340 aircraft**.\n\n**What it does:**\n- Requires owners and operators of specific SAAB SF340A and 340B aircraft to inspect and fix a problem with the **lower drag strut assembly** — a structural component that helps support the wing.\n- The issue is that **bolts and collars attaching this fitting have been losing their torque** (becoming loose), which could compromise structural integrity.\n\n**Who it affects:**\n- Owners and operators of SAAB SF340A aircraft with serial numbers -004 through -159\n- Owners and operators of SAAB 340B aircraft with serial numbers -160 through -166\n\n**What must be done:**\n- Follow the technical requirements set out in **Swedish LFV AD 1-049 Revision A** (Sweden's aviation safety authority issued the original safety notice)\n- Reference **SAAB Service Bulletin 340-54-027 Revision 1** for detailed instructions\n\n**Why this version matters:**\nThis is **Amendment 1**, which extends the deadline for compliance. The original directive required action by August 1991; this amendment gives Australian-registered aircraft until **14 November 1991** — an extra three months.\n\n**In short:** If you own one of these specific SAAB aircraft in Australia, you must check and tighten (or replace) the bolts on the lower drag strut assembly by November 1991 to prevent potential structural failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment does not change which aircraft are covered or the referenced technical requirement. It changes the compliance timing: the effective date for Australian registered aircraft is revised to 14 November 1991 (previously 8 August 1991), a three-month extension. The AD states this amendment reflects a revision of the Requirement Document that altered the compliance time. (Compliance; Amendment 1)"},"complexity_factors":["References and delegates technical detail to external documents (Swedish LFV AD 1-049 Rev A and SAAB service bulletin), requiring operators to obtain and interpret those documents (Requirement, Note).","Applicability limited to specific serial-number ranges, so compliance applies only to a defined subset of fleet (Applicability).","Amendment changes the compliance (effective) date rather than the substantive technical requirement, adding a timetable/administrative element to track (Compliance, Amendment 1).","The AD itself does not list step-by-step technical actions (it mandates compliance with another document), which creates a dependency on external technical material for implementation (Requirement, Note).","Short text but with operational implications (inspections/repairs, downtime, parts) implied by the background fault (Background)."],"plain_english_summary":"This amendment mandates operators of specified SAAB SF340A/340B aeroplanes to carry out the inspections and maintenance set out in Swedish LFV AD 1‑049 Revision A, with technical detail in SAAB service bulletin 340‑54‑027 Rev 1, because bolts and collars on the lower drag strut fitting have been losing torque. It affects the listed serial numbers, places costs and downtime on operators, and only changes the Australian compliance date to 14 November 1991."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sf340-29-amdt-1-lower-drag-strut-assembly","history":"/api/acts/ad-sf340-29-amdt-1-lower-drag-strut-assembly/history","analysis":"/api/acts/ad-sf340-29-amdt-1-lower-drag-strut-assembly/analysis","conflicts":"/api/acts/ad-sf340-29-amdt-1-lower-drag-strut-assembly/conflicts","importantCases":"/api/acts/ad-sf340-29-amdt-1-lower-drag-strut-assembly/important-cases","documents":"/api/acts/ad-sf340-29-amdt-1-lower-drag-strut-assembly/documents"}}