{"id":"F2006B09631","name":"AD/F100/3 - Engine Cowling - Inspection/Modification/Repair","slug":"ad-f100-3-engine-cowling-inspection-modification-repair","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54422,"registerId":"commonwealth-F2006B09631-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F100/3 - Engine Cowling - Inspection/Modification/Repair","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)  \nFokker F100 (F28 Mk 100) Series Aeroplanes\n\nAD/F100/3 Engine Cowling \\- Inspection/Modification/Repair 1/99\n\nApplicability: F28 Mk. 100 aircraft serial numbers 11244 through 11438.\n\nRequirement: Inspect the fixed engine cowling in accordance with Fokker Service bulletin F100-71- 016 dated 18 February 1994, and carry out repairs in Service Bulletin to restore the structure(s) to a serviceable state.\n\nNote: RLD Airworthiness Directive 94-038 (A) dated 21 February 1994 refers.\n\nCompliance: Before accomplishment of 15,000 flight hours since new.\n\nThis Airworthiness Directive becomes effective on 28 January 1999.\n\nBackground: Reports of excessive noise from the rear of the aircraft during flight led to the discovery of interference between the fixed engine cowl fasteners and the forward and aft engine crane beams. This Directive introduces an inspection to check for such interference and measures to restore the structure and prevent further recurrence of the interference.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope appears consistent with the directive’s stated corrective purpose: it targets a specific fleet segment and prescribes inspection/repair per the cited service bulletin to remedy identified interference. The AD does not broaden applicability or add unrelated obligations beyond inspection and restoration to serviceable condition."},"complexity_factors":["Narrow applicability to a defined serial‑number range (11244–11438) — requires accurate fleet tracking.","Mandates inspection and repair in accordance with an external Fokker Service Bulletin (F100‑71‑016 dated 18 Feb 1994) — dependence on an external document for procedures.","Repairs must “restore the structure(s) to a serviceable state” — involves engineering judgment and potential parts or structural work.","Compliance tied to flight hours (before 15,000 hours) — requires monitoring of individual aircraft utilisation.","Technical cause (interference between fixed cowl fasteners and forward/aft engine crane beams) — may require precise fit checks or modification.","Specified effective date (28 Jan 1999) and cross‑reference to prior AD (RLD 94‑038(A)) — administrative tracking for compliance history."],"plain_english_summary":"This airworthiness directive requires operators of Fokker F28 Mk 100 (F100) aircraft serial numbers 11244–11438 to inspect the fixed engine cowling and carry out any repairs per Fokker Service Bulletin F100‑71‑016 (18 Feb 1994) before 15,000 flight hours; it takes effect 28 Jan 1999. It responds to discovered interference between cowl fasteners and engine crane beams that caused excessive rear‑airframe noise. Operators pay for inspections/repairs and schedule maintenance; the Civil Aviation Safety Authority prescribes the standard and compliance deadline."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete airworthiness directive addressing a specific safety issue with defined aircraft. It has not expanded beyond its original purpose of addressing engine cowling interference."},"complexity_factors":["Single, specific technical requirement referencing an external manufacturer document (Fokker Service Bulletin)","Narrow applicability limited to specific aircraft serial number range","Simple compliance trigger (flight hours threshold)","No nested exceptions or conditional logic","No defined terms section","Single background issue with straightforward remediation"],"plain_english_summary":"This is a **safety order for specific Fokker F100 aircraft**.\n\n**What it does:**\n- Requires owners/operators of certain Fokker F100 planes (serial numbers 11244 to 11438) to inspect the engine covers (cowlings) for a specific problem\n- The problem: metal fasteners on the engine cover were rubbing against engine crane beams, causing excessive noise and potential structural damage\n- If damage is found, repairs must be done following the manufacturer's instructions\n\n**Who it affects:**\n- Airlines and operators flying Fokker F100 aircraft with serial numbers between 11244 and 11438\n- Maintenance crews responsible for these aircraft\n\n**Why it matters:**\n- Prevents structural damage that could affect flight safety\n- Addresses a known issue where engine cover parts were interfering with critical engine support structures\n- Must be completed before the aircraft reaches 15,000 total flight hours\n\n**Key deadline:** The inspection and any needed repairs must be done before the aircraft hits 15,000 flight hours since it was built."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f100-3-engine-cowling-inspection-modification-repair","history":"/api/acts/ad-f100-3-engine-cowling-inspection-modification-repair/history","analysis":"/api/acts/ad-f100-3-engine-cowling-inspection-modification-repair/analysis","conflicts":"/api/acts/ad-f100-3-engine-cowling-inspection-modification-repair/conflicts","importantCases":"/api/acts/ad-f100-3-engine-cowling-inspection-modification-repair/important-cases","documents":"/api/acts/ad-f100-3-engine-cowling-inspection-modification-repair/documents"}}