{"id":"F2006B03088","name":"AD/B747/187 - Centre Wing Fuel Tank Scavenge Pump","slug":"ad-b747-187-centre-wing-fuel-tank-scavenge-pump","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42447,"registerId":"commonwealth-F2006B03088-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/187 - Centre Wing Fuel Tank Scavenge Pump","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)  \nBoeing 747 Series Aeroplanes\n\nAD/B747/187 Centre Wing Fuel Tank Scavenge Pump 10/98\n\nDM\n\nApplicability: Model 747 series aeroplanes line positions 001 through 971 inclusive.\n\nRequirement: 1. Unless previously accomplished, perform a one time inspection to determine the part number (P/N) of the installed scavenge pump motor-impeller unit in accordance with Boeing Alert Service Bulletin (ASB) 747-28A2215 dated 14 May 1998. If the P/N is neither Boeing P/N 60B92403-5 nor Lear Romec P/N RR24680 no further action is required.\n\n    2. If the P/N is either Boeing P/N 60B92403-5 or Lear Romec P/N RR24680 either:\n\n    Replace the scavenge pump with a new or serviceable pump having P/N 60B92403-12, \\-13 or \\-18 (Intertechnique); or with a new or serviceable pump having P/N 60B92403-51 (Lear Romec).\n\nor\n\n    b. Deactivate the scavenge pump. The aeroplane may be operated with the scavenge pump deactivated in accordance with the provisions and limitations specified in the operator’s approved Master Minimum Equipment List.\n\nNote: Boeing ASB 747-28A2215, refers to the 747 Dispatch Deviation Guide as another source for deactivation of the scavenge pump.\n\n    3. Scavenge pumps with either Boeing P/N 60B92403-5 or Lear Romec P/N RR24680 are not be installed on any aeroplane to replace an existing unit.\n\nNote: FAA AD 98-14-17 Amdt 39-10650 refers.\n\nCompliance: 1. Within 60 days after the effective date of this directive.\n\n    2. Before further flight after the Requirement 1 inspection.\n\n    3. As of the effective date of this directive.\n\nThis airworthiness directive becomes effective on 5 August 1998.\n\nBackground: This directive supersedes AD/B747/179 Amdt 1 (FAA AD 97-25-06) which is cancelled. The FAA has received a report of damage to the internal wiring of a scavenge pump that had its electrical connector replaced in accordance with FAA AD 97-25-06. Investigation revealed that the damage to the wiring was caused by the replacement connector’s longer backshell, which provided insufficient clearance for the attachment screw for the internal ground wire of the scavenge pump motor.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nThis directive requires the inspection to determine the part number of the installed scavenge pump motor-impeller and, if necessary, replacement of the scavenge pump. This action will decrease the likelihood of short circuiting and failure within the electrical motor assembly, such failures could result in leakage of fuel from the electrical connector into the main landing wheel well or electrical arcing with consequent risk of fire.","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"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow scope: addressing a specific wiring defect in a specific fuel pump model on specific Boeing 747 aircraft. It supersedes a previous directive on the same issue but does not expand beyond the original safety purpose of preventing fuel leaks and fire hazards from the centre wing fuel tank scavenge pump."},"complexity_factors":["Multiple part numbers to identify and track (6 specific P/Ns mentioned across replacement and prohibited categories)","Conditional logic with branching requirements (inspection → if/then → replacement OR deactivation)","Cross-reference to external documents (Boeing Alert Service Bulletin 747-28A2215, FAA AD 98-14-17, operator's Master Minimum Equipment List)","Nested compliance deadlines (60 days for inspection, 'before further flight' for remediation, immediate prohibition on installation)","Technical aviation terminology requiring domain knowledge (scavenge pump, motor-impeller unit, backshell, line positions)"],"plain_english_summary":"This safety order requires airlines operating early-to-mid production Boeing 747s (line positions 001–971) to inspect the centre wing fuel tank’s scavenge pump for specific faulty part numbers. Faulty wiring can be damaged during repairs, risking fuel leaks and ignition.\n\nIf the pump is one of the identified models, operators must replace it with a safer pump or deactivate it (with operational restrictions), and must not reinstall the faulty models. The measure prevents fuel leaks/fire and supersedes the earlier AD/B747/179."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"This directive supersedes the earlier AD (AD/B747/179 Amdt 1) and shifts the corrective approach: it requires inspection of the scavenge pump P/N and either replacement with specified approved P/Ns or pump deactivation under the operator’s MMEL, and it prohibits reinstalling the previously used P/Ns (Requirement 1–3; Background). The scope therefore changed from the earlier connector-replacement focus to eliminating or removing specific pump units as the mitigation."},"complexity_factors":["Applicability limited to specific airframe range (Model 747, line positions 001–971) — narrows universe but requires fleet-level tracking (Applicability).","Multiple technical outcomes permitted: replace with specified Intertechnique or Lear Romec P/Ns or deactivate the pump under an operator’s MMEL — creates operational choice and reliance on MMEL approval (Requirement 2).","Hard prohibition on reinstalling certain P/Ns after effective date — imposes ongoing parts-control and inventory constraints (Requirement 3; Compliance 3).","Short mandatory timelines: inspection within 60 days and, if affected, remediation before next flight — operational scheduling and potential aircraft downtime (Compliance 1–2).","Dependence on external technical documents (Boeing ASB 747-28A2215, 747 Dispatch Deviation Guide, FAA AD 98-14-17) for inspection/deactivation procedures — increases procedural complexity and document-management burden (Requirement 1 Note; Background).","Costs and who pays: operators must perform inspections, source approved replacement pumps or manage MMEL deactivation — direct compliance costs and possible parts procurement lead times (Requirement 1–2; Compliance).","Safety-tradeoff clarity: the directive changes the technical fix from a connector replacement (previous AD) to pump replacement/deactivation to avoid wiring damage, altering maintenance practices (Background).","Enforcement and discretion: regulator prescribes required actions but allows operator discretion to choose replacement versus deactivation subject to MMEL limits — operational judgement and coordination with the operator’s approved procedures (Requirement 2)."],"plain_english_summary":"This airworthiness directive requires operators of Boeing 747 aircraft (line positions 001–971) to inspect the centre-wing scavenge pump motor-impeller part number. If a listed unsafe part number is fitted, the operator must either replace the pump with an approved part or deactivate the pump under the operator’s approved Master Minimum Equipment List before the next flight. The rule matters because it aims to reduce the risk of internal wiring damage that could cause fuel leakage or electrical arcing; operators bear the inspection and remediation costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-187-centre-wing-fuel-tank-scavenge-pump","history":"/api/acts/ad-b747-187-centre-wing-fuel-tank-scavenge-pump/history","analysis":"/api/acts/ad-b747-187-centre-wing-fuel-tank-scavenge-pump/analysis","conflicts":"/api/acts/ad-b747-187-centre-wing-fuel-tank-scavenge-pump/conflicts","importantCases":"/api/acts/ad-b747-187-centre-wing-fuel-tank-scavenge-pump/important-cases","documents":"/api/acts/ad-b747-187-centre-wing-fuel-tank-scavenge-pump/documents"}}