{"id":"F2006B03144","name":"AD/B747/247 Amdt 1 - Reduced Acceleration and Climb Performance","slug":"ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42516,"registerId":"commonwealth-F2006B03144-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/247 Amdt 1 - Reduced Acceleration and Climb Performance","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)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B747/247 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\nBoeing 747 Series Aeroplanes\n\nAD/B747/247\n\nAmdt 1\n\n  \nReduced Acceleration and Climb Performance 8/2001\n\nDM\n\nApplicability: Boeing Model 747-400, 747-400F series aeroplanes equipped with Pratt & Whitney Model PW 4000 engines.\n\nRequirement: Revise the Aircraft Flight Manual (AFM) by inserting a copy of the FAA Airworthiness Directive (AD) 2001-01-10 with Boeing Telex M-7200-00-02672, dated 1 November 2000, including the performance adjustments in “Performance for Operations of PW4000 Series Engines with FB2B or FB2T Fans Installed, 747-400”.\n\nWhen the information in Boeing Telex M-7200-00-02672 and its attachments have been incorporated as general revision of AFM, the FAA AD and the telex and its attachments are to be removed from AFM.\n\nNote: FAA AD 2001-01-10 Amendment 39-12080 refers.\n\nCompliance: Unless accomplished earlier, within 30 days from the effective date of this Directive.\n\nThis Amendment becomes effective on 12 July 2001.\n\nBackground: This Directive is being issued to correct the condition of Fan Thrust Deterioration Mode (FTDM) present on some PW4000 series engines fitted with early production fan blades. The thrust deterioration is due to erosion of fan blade’s leading edge and results in reduced acceleration and climb performance, relative to performance data in the AFM. The reduction in thrust may result in runway overruns or impact with an obstacle or terrain.\n\nThis amendment is being issued to correct the FAA AD referred.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 21 June 2001\n\n![](image.001.png)\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 27 June 2001.\n\n  \n\nPage 1 of 1","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment does not materially expand the scope beyond the original safety purpose. It revokes the prior AD and reissues a directive that narrowly requires AFM insertion of the FAA AD and Boeing telex for the same aircraft/engine combination to address the identified Fan Thrust Deterioration Mode. It remains a targeted operational/informational requirement rather than broadening to new aircraft types, additional regulatory powers, or unrelated obligations."},"complexity_factors":["Single narrow applicability (Boeing 747-400/-400F with PW4000 engines)","One primary action required (insert FAA AD and Boeing telex into AFM)","Short document: one-page AD with four main clauses (Applicability, Requirement, Compliance, Background)","Minimal number of defined terms or embedded conditions","Single external cross-reference (FAA AD 2001-01-10 and Boeing Telex M-7200-00-02672)","One conditional exception (remove inserted documents when incorporated as AFM general revision)"],"plain_english_summary":"**What this directive does (mechanically)**\n\n- Requires operators of Boeing 747-400 and 747-400F aeroplanes fitted with Pratt & Whitney PW4000 engines to update their Aircraft Flight Manual (AFM).\n- The update must insert the text of the FAA Airworthiness Directive 2001-01-10 together with Boeing Telex M-7200-00-02672 (dated 1 November 2000), including the specific performance adjustments titled “Performance for Operations of PW4000 Series Engines with FB2B or FB2T Fans Installed, 747-400”. (See: Requirement, Applicability.)\n- When that information has been incorporated into the AFM as a formal general revision, the FAA AD and the Boeing telex and attachments may be removed from the AFM. (See: Requirement.)\n- Must be done within 30 days of the AD’s effective date. (See: Compliance.)\n\n**Who is directly affected**\n\n- Aircraft operators/owners who operate Boeing 747-400 or 747-400F aeroplanes with Pratt & Whitney PW4000 engines (the legal obligation is on the operator to comply with the AD). (Applicability; Requirement.)\n- Flight crews and dispatcher/planning staff, because they must use the revised AFM performance data for take-off and climb planning.\n- Maintenance/airworthiness departments, which must manage the AFM revision and record compliance.\n\n**Why the change was required (stated safety reason)**\n\n- The AD responds to a condition called Fan Thrust Deterioration Mode (FTDM) affecting some PW4000 engines with early-production fan blades. The leading edges of those fan blades can erode, lowering engine thrust.\n- Reduced thrust can lower acceleration and climb performance compared with the AFM’s published performance figures. The AD’s stated safety concern is that the reduction could contribute to runway overruns or collision with obstacles or terrain. (See: Background.)\n\n**Practical effects and choices created by the AD**\n\n- Immediate administrative action: operators must insert the FAA AD and Boeing telex into the AFM within 30 days. That is an operational compliance item rather than a physical modification. (Requirement; Compliance.)\n- Operational consequences: the telex includes adjusted performance figures. In practice this can change crew decisions about take-off weight, required runway length, flap/thrust settings, and climb profiles — potentially forcing reduced payload or fuel imposition to meet performance/obstacle-clearance requirements.\n- Cost-bearer: the operator bears direct costs (staff time to revise and distribute the AFM and to brief crews), and indirect costs if the revised performance figures require payload limits, different fuel planning, or changed routings. Any further maintenance or blade replacement actions called for by the FAA/Boeing documents (if applicable) would also be paid by operators. (Requirement; Background.)\n\n**Implementation, compliance burden and timing**\n\n- Short compliance window: the AD gives 30 days from the effective date for insertion into the AFM, so operators must act quickly to update manuals and brief crews. (Compliance.)\n- Record-keeping: operators must retain evidence of compliance as part of their continuing airworthiness records; the AD does not itself prescribe additional inspection tasks or mandatory blade replacement, but it cross-references FAA/Boeing instructions that may contain further work-scope. (Requirement.)\n- Removal condition: the temporary insertion can be removed once the AFM’s next general revision incorporates the FAA AD and telex material, which reduces duplicate entries but requires diligence to ensure the content is properly integrated. (Requirement.)\n\n**Trade-offs, incentives and risks (mechanical assessment)**\n\n- Safety vs. operational efficiency: the directive reduces the risk of operations being conducted with optimistic performance figures by forcing use of corrected numbers; the trade-off is potential short-term efficiency loss (payload or range reductions) for affected flights.\n- Concentrated burden: only operators of the specified model/engine combination are affected, so costs are concentrated on a subset of 747 operators rather than spread across the industry. (Applicability.)\n- Administrative simplicity: the AD takes the simpler route of mandating an AFM revision (informational/operational control) rather than an immediate mandatory hardware modification, which lowers immediate cost but may leave longer-term maintenance choices to operators and manufacturers.\n- Compliance risk: if operators do not correctly incorporate and use the adjusted performance data, the safety risk the AD addresses could persist; the AD imposes a clear, time-limited duty to change manuals to reduce that risk. (Requirement; Compliance.)\n\n**Key sections cited**\n- Applicability: identifies Boeing 747-400 and 747-400F with Pratt & Whitney PW4000 engines.\n- Requirement: mandates insertion of FAA AD 2001-01-10 and Boeing Telex M-7200-00-02672 (including performance adjustments) into the AFM and specifies removal conditions.\n- Compliance: 30 days from effective date.\n- Background: explains FTDM, blade leading-edge erosion, and the safety hazard (reduced acceleration and climb performance)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is an amendment to an existing Airworthiness Directive, but it does not expand scope beyond the original safety purpose. The amendment simply corrects the reference to the FAA directive that airlines need to insert into their flight manuals. The original intent was to address the FTDM engine performance issue; this amendment maintains that same narrow, safety-focused scope."},"complexity_factors":["Single, clearly defined applicability (one aircraft model, one engine type)","Straightforward requirement: insert specific document into flight manual","No nested conditions or exceptions","Simple compliance deadline (30 days from effective date)","Minimal cross-referencing (only to FAA AD 2001-01-10 and Boeing Telex)","Short document (1 page)","Only 2 defined terms used (AFM, FTDM — both explained in context)"],"plain_english_summary":"This FAA safety order addresses Boeing 747-400 and 747-400F aircraft powered by Pratt & Whitney PW4000 engines, requiring airlines to insert an urgent AFM/telex within 30 days of July 12, 2001. It fixes dangerous fan‑blade leading‑edge wear that can trigger Fan Thrust Deterioration Mode, reducing takeoff/climb performance and risking runway overruns or failure to clear obstacles. A permanent AFM revision from the manufacturer will replace the temporary insert."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance","history":"/api/acts/ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance/history","analysis":"/api/acts/ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance/analysis","conflicts":"/api/acts/ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance/conflicts","importantCases":"/api/acts/ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance/important-cases","documents":"/api/acts/ad-b747-247-amdt-1-reduced-acceleration-and-climb-performance/documents"}}