{"id":"F2006B04269","name":"AD/BEECH 90/87 - Engine Mount Assembly Attachment Bolts","slug":"ad-beech-90-87-engine-mount-assembly-attachment-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44074,"registerId":"commonwealth-F2006B04269-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 90/87 - Engine Mount Assembly Attachment Bolts","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)  \nBeechcraft 90 and 65-90 (King Air) Series Aeroplanes\n\nAD/BEECH 90/87 Engine Mount Assembly Attachment Bolts 10/92\n\nApplicability: Models and serial numbers as listed in Beech SB 2432.\n\nRequirement: 1. Individually remove each engine truss-to-firewall bolt and determine whether the bolt is manufactured by Dumont Aviation as specified by Figure 2 of, and in accordance with paragraphs 1 and 2 of the ACCOMPLISHMENT INSTRUCTIONS section of Beech SB 2432. Only one engine truss-to-firewall bolt shall be removed at any given time.\n\n2. Replace any bolt manufactured by Dumont Aviation as identified in Requirement 1 of this Directive with a new bolt part number MS20006-20 /M/.\n\nNote: FAA AD 92-15-01 Amdt 39-8294 refers.\n\nCompliance: 1. Within 150 hours’ time in service after 17 September 1992.\n\n2. Prior to further flight.\n\nBackground: This Directive requires a one-time visual inspection of all engine mount assembly attachment bolts to determine whether bolts that could have been improperly heat treated are installed, and replacement of any such bolts.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"No — the Directive preserves the original, safety‑limited scope: a one‑time visual/identification inspection of engine truss‑to‑firewall bolts on models listed in Beech SB 2432 and replacement of any bolts identified as Dumont‑manufactured and potentially improperly heat treated (see Requirement and Background)."},"complexity_factors":["Reliance on an external service bulletin (Beech SB 2432) and its Figure 2 for correct identification of affected bolts","Physical removal and individual inspection of each engine truss‑to‑firewall bolt (procedural time and labour burden)","Directive requires replacement with a specific part number (MS20006-20/M) where Dumont-manufactured bolts are found","Compliance timing: inspection within 150 flight hours from the specified date and replacement prior to further flight (scheduling/operational impact)","Limited scope (one‑time action) but potential aircraft downtime while inspections/replacements are done","Cross-reference to FAA AD 92-15-01 for related regulatory context"],"plain_english_summary":"Requires owners/operators of Beechcraft 90 and 65‑90 series aeroplanes to remove each engine truss‑to‑firewall bolt (one at a time), identify bolts manufactured by Dumont Aviation per Beech SB 2432, and replace any such bolts with part MS20006‑20/M. Inspection must occur within 150 flight hours after 17 September 1992; replacement before further flight. Operators pay for the inspection and replacement and must follow Beech SB 2432 identification procedures."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive focused on a specific mechanical defect in a specific aircraft type. The scope remains exactly as intended: a one-time inspection and replacement requirement for potentially defective engine mount bolts."},"complexity_factors":["Very short document (under 300 words)","Only 2 defined requirements with clear sequential steps","Single cross-reference to FAA AD 92-15-01 (informational only)","No nested exceptions or conditional logic","Clear applicability statement referencing external document (Beech SB 2432)","Simple compliance timeline (150 hours or before further flight)"],"plain_english_summary":"This AD requires operators of certain Beechcraft King Air 90 and 65-90 series (as listed in Beechcraft Service Bulletin 2432) to inspect engine mount bolts because some Dumont Aviation bolts may have been improperly heat-treated and could fail. Inspect bolts one at a time and replace any Dumont-made bolt with part MS20006-20 within 150 flight hours of 17 September 1992; any replaced bolt must be addressed before further flight. This prevents potential in-flight engine separation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-90-87-engine-mount-assembly-attachment-bolts","history":"/api/acts/ad-beech-90-87-engine-mount-assembly-attachment-bolts/history","analysis":"/api/acts/ad-beech-90-87-engine-mount-assembly-attachment-bolts/analysis","conflicts":"/api/acts/ad-beech-90-87-engine-mount-assembly-attachment-bolts/conflicts","importantCases":"/api/acts/ad-beech-90-87-engine-mount-assembly-attachment-bolts/important-cases","documents":"/api/acts/ad-beech-90-87-engine-mount-assembly-attachment-bolts/documents"}}