{"id":"F2006B09815","name":"AD/F28/80 Amdt 1 - Frame Station 10790 Coupling Fitting Bolts","slug":"ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54745,"registerId":"commonwealth-F2006B09815-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F28/80 Amdt 1 - Frame Station 10790 Coupling Fitting 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)  \nFokker F28 Series Aeroplanes\n\nAD/F28/80\n\nAmdt 1\n\n  \nFrame Station 10790 Coupling Fitting Bolts 13/97\n\nApplicability: F28-1000 to \\-4000 Series, Serial Numbers 11003 to 11201, 11991 and 11992 with SB F28/53-125 installed.\n\nRequirement: Action in accordance with the Instructions for Part 1 of Fokker F28 SB F28/53-143.\n\nNote: Netherlands AD 1996-119(A) refers.\n\nCompliance: Within 3000 flight cycles after 2 January 1996 or before 1 February 1998, whichever occurs first.\n\nThis Amendment becomes effective on 4 December 1997.\n\nBackground: A new coupling was introduced at SB F28/53-125 to replace the original 7079-T6 coupling which was subject to stress corrosion and consequent SIP inspection. It has been discovered that the torque values specified in SB F28/53-125 are below what is actually required. This directive is issued to ensure that the coupling bolts are torqued to the value specified in the requirement document.\n\nThis amendment corrects a misleading statement in the background, which referred to a steel coupling. The replacement coupling is made of 7075-T73. The compliance date has also been corrected.\n\nThe original issue of this Airworthiness Directive became effective on 2 January 1996.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a minor amendment to a specific airworthiness directive. It corrects factual errors in the background description (material type of coupling) and the compliance date. The scope remains limited to the original safety issue regarding bolt torque on specific Fokker F28 aircraft."},"complexity_factors":["Single, specific technical requirement (torque bolts to specified value)","Narrow applicability (specific aircraft series and serial numbers)","Simple conditional compliance deadline (whichever occurs first)","One cross-reference to a service bulletin (SB F28/53-143)","No defined terms section","Short document (under 200 words)","Single amendment purpose (correcting background description and date)"],"plain_english_summary":"This safety amendment corrects a prior directive for certain Fokker F28s requiring operators to re-torque bolts at Frame Station 10790 after a replacement part was installed with incorrect, too-loose tightening instructions. It affects specific serial-numbered aircraft that received that service bulletin and corrects the coupling material ID and the compliance deadline. Operators had to complete the re-torque within the specified flight-cycle/deadline to avoid structural safety risks."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment does not change the core requirement to re-torque the coupling bolts per SB F28/53-143. It corrects a misleading background statement about the coupling material (identifies it as 7075‑T73 rather than 'steel') and corrects the compliance date wording; the action required and affected fleet remain the same."},"complexity_factors":["Narrow, technical applicability: specific F28 models and serial numbers with SB F28/53-125 installed — requires operator record checks.","External cross-reference: mandatory compliance references a separate service bulletin (F28/53-143) for the exact torque instructions.","Compliance metric: deadline tied to flight cycles and a calendar cut-off (3000 flight cycles after 2 Jan 1996 or before 1 Feb 1998) — needs accurate flight-cycle accounting.","Technical execution: requires correct torque values and tooling; material difference (7075‑T73 vs earlier alloy) is noted and affects required torque.","Amendment nature: correction of background wording and date (not substantive change) — potential for operator confusion without reading amendment text.","Enforcement traceability: operators must document completion; maintenance organisations bear operational and cost burdens."],"plain_english_summary":"This directive requires operators of specified Fokker F28-1000 to -4000 aeroplanes (listed serial numbers) with Service Bulletin F28/53-125 fitted to re-torque the coupling fitting bolts at frame station 10790 in accordance with Part 1 of Fokker SB F28/53-143. Aircraft operators and their maintenance organisations must complete and record the work within 3000 flight cycles after 2 January 1996 or before 1 February 1998; they bear the cost and scheduling effects. The amendment corrects a background statement about coupling material (7075‑T73) and fixes the compliance date."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts","history":"/api/acts/ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts/history","analysis":"/api/acts/ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts/analysis","conflicts":"/api/acts/ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts/conflicts","importantCases":"/api/acts/ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts/important-cases","documents":"/api/acts/ad-f28-80-amdt-1-frame-station-10790-coupling-fitting-bolts/documents"}}