{"id":"F2006B10410","name":"AD/HS 125/130 Amdt 1 - Engine and Flight Data Monitoring","slug":"ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116083,"registerId":"commonwealth-F2006B10410-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HS 125/130 Amdt 1 - Engine and Flight Data Monitoring","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 125 Series Aeroplanes\n\nAD/HS 125/130\n\nAmdt 1\n\n  \nEngine and Flight Data Monitoring 11/94\n\nDM\n\nApplicability: BAe125 series aircraft fitted with AlliedSignal TFE731-3 series engines not incorporating AlliedSignal Service Bulletin TFE731-72-3502.\n\nRequirement: 1. Amend the Limitation Section of the Airplane Flight Manual (AFM) to reflect the requirements of Federal Aviation Administration (FAA) Airworthiness Directive (AD) 94-07-03, paragraphs (a), (1), (2), (3) and (4) by inserting AFM amendment A/125-700B/12, and\n\n    2. calculate data recorded in accordance with FAA AD 94-07-03, paragraph (b), (1), and\n\n    3. action in accordance with FAA AD 94-07-03, paragraph (b), (2), and\n\n    4. action in accordance with FAA AD 94-07-03, paragraph (c).\n\n    5. Compliance with the Requirements of CAO 106, AD/TFE731/25 on both engines provides a terminating action for the Requirements 1 through 4 of this Directive.\n\nCompliance: Effective 14 September 1994; Unless previously accomplished, prior to further flight.\n\nBackground: This Directive was originally issued in September 1992 to address two reports of uncontained failure of AlliedSignal TFE731-3 first stage low pressure turbine discs following failure of certain low pressure turbine nozzle airseals. Following a report of a further low pressure turbine disc failure, this Directive has been amended to reflect more stringent requirements for verifying low pressure rotor lock-up during engine start and for the detection of rubbing noises following engine shut down.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"This amendment tightened the Directive after an additional low pressure turbine disc failure. It added more stringent start-up verification and post-shutdown rub-noise detection measures, required an AFM amendment and specified data-calculation and follow-up actions by reference to FAA AD 94-07-03, while allowing termination of these requirements if CAO 106, AD/TFE731/25 is complied with on both engines."},"complexity_factors":["Applicability limited to BAe125 series with specific AlliedSignal TFE731-3 engines and excludes aircraft with Service Bulletin TFE731-72-3502 (narrow scope but precise technical trigger).","Multiple cross-references to FAA AD 94-07-03 (paragraphs (a),(b),(c)) for substantive requirements, increasing interpretive reliance on external text.","Requires AFM amendment, data calculation, monitoring and remedial actions — technical maintenance and engineering tasks rather than simple paperwork.","Immediate compliance deadline ('prior to further flight') creates operational scheduling pressure for operators.","Provides a terminating action via CAO 106, AD/TFE731/25 if installed on both engines, creating a conditional compliance pathway.","Safety-critical subject matter (LP turbine disc failure detection and start-up verification) demands specialist expertise and accurate data handling."],"plain_english_summary":"This Directive requires operators of BAe 125 aeroplanes with AlliedSignal TFE731-3 engines (unless they have a specified service bulletin installed) to amend the Airplane Flight Manual and perform engine and flight data monitoring, calculations and follow-up actions as set out in the referenced FAA AD. Compliance was required before further flight from 14 September 1994. Operators bear the cost and must carry out technical inspections and corrective actions; compliance is extinguished if both engines meet CAO 106, AD/TFE731/25."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"Originally issued in 1992 to address specific turbine disc failures, this Amendment 1 (1994) expanded the scope by adding 'more stringent requirements' — specifically new monitoring for rotor lock-up during start and rubbing noise detection after shutdown. The terminating action provision (item 5) also represents a scope expansion, creating an alternative compliance pathway not present in the original directive."},"complexity_factors":["Multiple nested compliance pathways (direct compliance vs terminating action via CAO 106/AD/TFE731/25)","Cross-references to external US FAA directive (AD 94-07-03) without reproducing its full text","Specific technical applicability criteria (engine model + service bulletin incorporation status)","Conditional effective date with 'unless previously accomplished' exception","Technical aviation terminology requiring domain knowledge (AFM, uncontained failure, low pressure turbine nozzle airseals, rotor lock-up)"],"plain_english_summary":"This AD mandates safety measures for BAe 125 jets with AlliedSignal TFE731-3 engines (unless already modified by SB TFE731-72-3502). It requires operators to update the flight manual with new limits, record and review engine data, take corrective action, and follow enhanced shutdown checks — unless both engines already comply with CAO 106 and AD/TFE731/25.\n\nWhy it matters: the rule aims to stop catastrophic, uncontained turbine-disc failures linked to faulty airseals by forcing monitoring of rotor lock-up at start and grinding noises after shutdown."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring","history":"/api/acts/ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring/history","analysis":"/api/acts/ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring/analysis","conflicts":"/api/acts/ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring/conflicts","importantCases":"/api/acts/ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring/important-cases","documents":"/api/acts/ad-hs-125-130-amdt-1-engine-and-flight-data-monitoring/documents"}}