{"id":"F2006B10948","name":"AD/JETSTREAM/78 - Main Landing Gear Bay Auxiliary Spar","slug":"ad-jetstream-78-main-landing-gear-bay-auxiliary-spar","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56515,"registerId":"commonwealth-F2006B10948-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JETSTREAM/78 - Main Landing Gear Bay Auxiliary Spar","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)  \nBritish Aerospace BAe 3100 (Jetstream) Series Aeroplanes\n\nAD/JETSTREAM/78 Main Landing Gear Bay Auxiliary Spar 8/98\n\nApplicability: All Jetstream Series 3200 aircraft.\n\nRequirement: Inspect in accordance with British Aerospace Regional Aircraft Mandatory Service Bulletin 57-A-JA 980441.\n\nNote: UK CAA AD 001-04-98 refers.\n\nCompliance: Unless the initial inspection is already accomplished; inspect in accordance with Part 1 of the Requirement document before 23 July 1998. Inspect in accordance with Part 2 of the Requirement document before 31 August 1998.\n\nThis airworthiness directive becomes effective on 16 July 1998.\n\nBackground: A main landing gear bay auxiliary spar lower boom has been found cracked in service. Cracking of the boom can cause a major reduction in airframe structural integrity.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive addressing a specific structural defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating safety inspections for the identified cracking issue."},"complexity_factors":["Very short document (under 200 words)","Only 1 defined term implicitly referenced (the service bulletin)","Simple conditional logic (single exemption: 'unless already accomplished')","No cross-references to other legislation beyond a single note about a UK equivalent directive","Clear, single-purpose requirement with two sequential deadlines","No nested exceptions or complex definitions section"],"plain_english_summary":"This is a **safety order for specific aircraft**.\n\n**What it does:**\nThis document is an **Airworthiness Directive (AD)** — a mandatory safety instruction issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of **British Aerospace Jetstream 3200 series aircraft** to inspect a specific part of the plane: the **main landing gear bay auxiliary spar** (a structural support beam near where the wheels fold up into the fuselage).\n\n**Why it matters:**\nA cracked spar was discovered in an aircraft already in service. If this crack goes undetected, it could seriously weaken the plane's structure and potentially lead to structural failure. This directive forces inspections to catch the problem before it becomes dangerous.\n\n**Who must comply:**\n- All operators of Jetstream Series 3200 aircraft\n- Maintenance organisations servicing these aircraft\n\n**What must be done:**\n- **First inspection:** By 23 July 1998 — check the spar according to Part 1 of the referenced British Aerospace service bulletin\n- **Second inspection:** By 31 August 1998 — follow Part 2 of the same bulletin\n- (If already inspected, you're exempt from the first deadline)\n\n**Key point:** This is not optional. Flying without completing these inspections violates civil aviation safety regulations."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text sets out a targeted, time-limited requirement: inspect the main landing gear bay auxiliary spar lower boom on all Jetstream Series 3200 aircraft in accordance with the specified manufacturer service bulletin, with two compliance deadlines and an effective date. The directive's stated scope (affected aircraft and required inspections) is explicit in the document and there is no indication within the text that the scope has been altered from the instrument's stated purpose."},"complexity_factors":["Requires following an external technical document (British Aerospace Mandatory Service Bulletin 57-A-JA 980441) rather than specifying inspection steps in the AD itself (Requirement).","Two-part inspection with separate, near-term compliance deadlines (Part 1 before 23 July 1998; Part 2 before 31 August 1998) adds scheduling complexity for operators (Compliance).","Applies to an entire aircraft type (all Jetstream Series 3200), concentrating compliance obligations on a specific operator group (Applicability).","Safety-critical issue (risk of major reduction in structural integrity) increases priority and may require rapid mobilisation of maintenance resources (Background).","Cross-reference to an overseas regulator's AD (UK CAA) may require operators to reconcile guidance across jurisdictions (Note)."],"plain_english_summary":"This AD requires owners/operators and their maintenance providers of all British Aerospace Jetstream Series 3200 aeroplanes to inspect the main landing gear bay auxiliary spar lower boom exactly as set out in Mandatory Service Bulletin 57-A-JA 980441. It became effective 16 July 1998 and mandates Part 1 inspections by 23 July 1998 and Part 2 by 31 August 1998 to detect cracking that could severely reduce airframe integrity."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jetstream-78-main-landing-gear-bay-auxiliary-spar","history":"/api/acts/ad-jetstream-78-main-landing-gear-bay-auxiliary-spar/history","analysis":"/api/acts/ad-jetstream-78-main-landing-gear-bay-auxiliary-spar/analysis","conflicts":"/api/acts/ad-jetstream-78-main-landing-gear-bay-auxiliary-spar/conflicts","importantCases":"/api/acts/ad-jetstream-78-main-landing-gear-bay-auxiliary-spar/important-cases","documents":"/api/acts/ad-jetstream-78-main-landing-gear-bay-auxiliary-spar/documents"}}