{"id":"F2008L00152","name":"AD/B747/272 Amdt 1 - Thrust Reverser Directional Pilot Valve","slug":"ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72303,"registerId":"commonwealth-F2008L00152-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 747 Series Aeroplanes","sectionType":"division","heading":"Boeing 747 Series Aeroplanes","content":"### Boeing 747 Series Aeroplanes\n\n| AD/B747/272 Amdt 1 | Thrust Reverser Directional Pilot Valve | 3/2008 DM |\n| ------------------ | --------------------------------------- | --------- |\n\n| Applicability: | Model 747 series aeroplanes with General Electric CF6-80C2 series engines.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. (a) For aeroplanes not modified in accordance with Boeing Service Bulletin (SB) 747-78-2151 or production equivalent, carry out and successfully accomplish a functional test of the Directional Pilot Valve (DPV) of the thrust reversers to detect pneumatic leakage, in accordance with Boeing Alert SB747-78A2170 dated 21 October 1999.(b) For aeroplanes modified in accordance with Boeing SB 747-78-2151 or production equivalent, carry out and successfully accomplish a functional test of the DPV of the thrust reversers to detect pneumatic leakage, in accordance with Boeing Alert SB 747-78A2170 dated 21 October 1999.2. Repeat and successfully accomplish a functional test of Requirement 1(a).3. Repeat and successfully accomplish a functional test of Requirement 1(b).4. If any functional test required by Requirement 1, 2 or 3 of this Directive cannot be successfully carried out in accordance with the reference service bulletin, or if any discrepancy is detected during any functional test, repair in accordance with the Aircraft Maintenance Manual.5. Repeat Requirement 1 functional tests if any discrepancies have been corrected under Requirement 4 during compliance with Requirement 1, 2 or 3.Production Equivalent Functional tests accomplished in accordance with a production equivalent for aeroplanes modified during production are acceptable as equivalent to the initial functional test required by Requirement 1(b) of this Directive. Therefore, in this case, compliance with Requirement 1(b) is not necessary.Later revisions of the above SB, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2000-17-06 are considered acceptable for compliance with the equivalent Requirements of this Directive.Note: FAA AD 2000-17-06 Amdt 39-11880 refers. |\n\n| Compliance: | For Requirement 1:(a) Remains unchanged as detailed in the original issue of this Directive as: Within 30 days after 5 June 2002 (the effective date of the original issue of this Directive) unless previously accomplished.(b) Remains unchanged as detailed in the original issue of this Directive as: With the exception of aeroplanes modified and functionally tested in accordance with a production equivalent, within 60 days after 5 June 2002, unless previously accomplished.For Requirement 2: At intervals not exceeding 1,000 flight hours.For Requirement 3: At intervals not exceeding 6,000 flight hours.For Requirement 4: Prior to further flight after the effective date of this Directive.For Requirement 5: Prior to further flight after the effective date of this Directive |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|             | This Amendment becomes effective on 23 January 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n| Background: | A possible leakage of the thrust reverser Directional Pilot Valve (DPV), due to a poppet valve being slightly jammed open or a leaking o-ring, has been identified by a report to the FAA as a latent failure of the fail-safe features of the thrust reverser system. The actions specified in this Directive are intended to ensure the integrity of the fail-safe features by preventing possible failure modes that could result in inadvertent deployment of the thrust reverser in flight.This amendment includes a statement approving the use of later FAA approved service bulletins which have been approved by the FAA as an AMOC to the referred FAA AD. There is no change to the requirements or compliance periods.The original issue of this AD became effective on 5 June 2002.        |\n\n![](image.001.png)  \nCharles Lenarcic  \nDelegate of the Civil Aviation Safety Authority\n\n16 January 2008","sortOrder":0},{"sectionNumber":"AD/B747/272 Amdt 1","sectionType":"part","heading":"AD/B747/272 Amdt 1","content":"## AD/B747/272 Amdt 1","sortOrder":1},{"sectionNumber":"Thrust Reverser Directional Pilot Valve","sectionType":"part","heading":"Thrust Reverser Directional Pilot Valve","content":"## Thrust Reverser Directional Pilot Valve","sortOrder":2},{"sectionNumber":"3/2008 DM","sectionType":"part","heading":"3/2008 DM","content":"## 3/2008 DM","sortOrder":3}],"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":4,"scope_assessment":{"changed":true,"description":"The amendment does not change the AD's substantive inspection, repair or compliance-period requirements but expands accepted compliance methods by approving later FAA‑approved service bulletins as AMOCs. In practical terms this widens acceptable documentation/methods for meeting the same obligations without altering who must comply or the timing of actions."},"complexity_factors":["Multiple specified compliance timings (initial 30/60 days; repeat intervals 1,000 and 6,000 flight hours; repairs prior to further flight) increase scheduling complexity (Compliance section).","Different treatment depending on modification status (unmodified vs modified per Boeing SB 747-78-2151 or production equivalent) requires operators to track configuration history (Requirement 1(a)/(b)).","Acceptance of later FAA‑approved service bulletins as Alternate Methods of Compliance (AMOC) introduces external regulatory cross‑references to FAA AD 2000-17-06 and potential need to verify FAA approvals.","Requirement to repair discrepancies in accordance with the Aircraft Maintenance Manual creates technical repair dependency on OEM maintenance procedures and certificated maintenance organisations (Requirement 4).","Interplay between Boeing Alert Service Bulletin dated 21 October 1999, production equivalents, and later SB revisions requires document control and validation of which service instructions satisfy the AD.","Operational impact: inspections detect pneumatic leakage (a technical, non-routine failure mode) which may result in unscheduled downtime and parts/labour costs.","Administrative burden for record‑keeping and demonstrating compliance to the Civil Aviation Safety Authority, including confirming production‑equivalent functional tests where applicable."],"plain_english_summary":"Requires operators of Boeing 747 series aeroplanes fitted with General Electric CF6‑80C2 engines to perform functional tests of the thrust reverser Directional Pilot Valve (DPV) to detect pneumatic leakage, repair any defects before further flight, and repeat tests at set intervals. The amendment additionally accepts later FAA‑approved service bulletins as alternate methods of compliance.\n\nAirlines and maintenance providers pay for the inspections, corrective work and scheduling; compliance deadlines (initial within 30–60 days; repeats at 1,000 and 6,000 flight hours) affect maintenance planning and aircraft availability."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope. The 2008 amendment explicitly states there is 'no change to the requirements or compliance periods' — it only adds flexibility by recognising later FAA-approved service bulletin revisions as acceptable alternatives."},"complexity_factors":["Multiple conditional pathways based on aircraft modification status (modified vs unmodified)","Cross-references to external Boeing Service Bulletins and FAA Airworthiness Directives","Nested compliance timelines (initial compliance vs recurring intervals)","Exception handling for 'production equivalent' modifications","Circular logic in Requirement 5 (retesting after repairs made during compliance with Requirements 1-3)","Dual-track maintenance schedules (1,000 vs 6,000 hour intervals depending on modification status)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Boeing 747s with GE CF6-80C2 engines to test the thrust-reverser Directional Pilot Valve for air leaks, repair any faults before flight, and perform recurring checks (shorter intervals for unmodified vs. modified aircraft). It prevents inadvertent in‑flight reverser deployment. Amendment 1 doesn’t change requirements — it only allows use of later FAA‑approved Boeing service bulletins as alternatives."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve","history":"/api/acts/ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve/history","analysis":"/api/acts/ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve/analysis","conflicts":"/api/acts/ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve/conflicts","importantCases":"/api/acts/ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve/important-cases","documents":"/api/acts/ad-b747-272-amdt-1-thrust-reverser-directional-pilot-valve/documents"}}