{"id":"F2006B09971","name":"AD/FSM/28 - Hamilton Standard JFC118 Fuel Leak Inspection","slug":"ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55253,"registerId":"commonwealth-F2006B09971-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/FSM/28 - Hamilton Standard JFC118 Fuel Leak Inspection","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nFuel Supply and Metering Equipment\n\nAD/FSM/28 Hamilton Standard JFC118 Fuel Leak Inspection 13/90 TX\n\nApplicability: Hamilton Standard hydro-mechanical units (HMU) fitted to Pratt and Whitney Canada PW115, PW118, PW118A, PW120, PW120A, PW121 and JT15D-4C\n\nengines, as listed in Hamilton Standard Service Bulletins: JFC118-10-73-14 R1,\n\nJFC118-11-73-15 R1, JFC118-12-73-16 R1, JFC118-30-73-15 R1, JFC118-31-73-14 R1.\n\nRequirement: 1. Inspect the HMU for evidence of fuel leakage as detailed in the applicable engine Maintenance Manual, or Overhaul Manual, or visually inspect the HMU for fuel leakage within 30 minutes of engine shutdown.\n\n2. Replace HMU with a HMU which has been inspected or repaired by Hamilton Standard and identified with MSO ?90-001?, or a once only internal inspection of the applicable HMU, and if required, replacement of torque motor transfer tube packing and back up retainer ring in accordance with the applicable Service Bulletin.\n\nNote: Transport Canada AD CF90-24 R1 refers.\n\nCompliance: Effective 30 October 1990:\n\n    Within 10 flight hours, and thereafter at intervals not to exceed 10 flight hours until compliance with Requirement 2.\n\n    2. At next engine shop visit.\n\nBackground: This Directive has been issued to require inspection of certain Hamilton Standard HMUs as fitted to certain PW100 and JT15D series engines. The Requirement follows advice that incorrect assembly of an internal seal may result in fuel leakage from the HMU.","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 is a standard, narrow airworthiness directive addressing a specific manufacturing defect in specific engine models. It has not expanded beyond its original safety purpose."},"complexity_factors":["Short, single-purpose directive (approximately 250 words)","Only 4 defined technical references (the Service Bulletin numbers)","Simple two-stage compliance structure (interim inspections + permanent repair)","No nested conditional logic or cross-references to other legislation","Clear applicability section limiting scope to specific engine models","Single background explanation with straightforward causal chain (assembly error → seal failure → fuel leak)"],"plain_english_summary":"This AD requires operators of aircraft with Hamilton Standard hydro‑mechanical fuel control units on specified Pratt & Whitney Canada engines to inspect and repair affected HMUs because incorrect assembly can allow an internal seal to fail and cause engine fuel leaks (fire risk). It mandates repeated short‑interval leak checks until a permanent fix—either a factory‑inspected replacement or an internal inspection and seal replacement per the manufacturer’s service bulletin—is completed."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive implements inspections and a mandated repair/replacement at next engine shop visit to address incorrectly assembled internal seals that may leak fuel; it applies only to the listed HMUs and engine models and does not expand obligations beyond those units. The Background and Requirement sections show the measure targets the stated assembly defect and sets time-bound inspection and shop‑visit obligations (Background; Requirement; Compliance)."},"complexity_factors":["Applicability: multiple engine models and HMU part lists are referenced, requiring operators to determine whether their specific HMU is listed (Applicability).","Cross-references to external documents: inspections are to follow the applicable engine Maintenance Manual or Overhaul Manual, or specific Hamilton Standard Service Bulletins, adding dependency on multiple external technical documents (Requirement).","Two-tier compliance timing: recurring inspections every 10 flight hours until final repair/replacement, plus a visual inspection window within 30 minutes after shutdown, creates ongoing operational scheduling and monitoring obligations (Requirement; Compliance).","Repair/replacement options and identification: acceptance of HMUs 'inspected or repaired by Hamilton Standard and identified with MSO \"90-001\"' or a once-only internal inspection adds procedural variation and record-keeping requirements (Requirement).","Specific parts work: possible replacement of torque motor transfer tube packing and backup retainer ring per service bulletin introduces discrete maintenance tasks and parts procurement considerations (Requirement).","Inter-jurisdictional reference: the AD notes a related Transport Canada AD, implying coordination or comparison with another regulator's remedial steps (Note).","Compliance locus and costs: the operator/maintenance organisation bears inspection, labour and replacement costs and must schedule a shop visit for final compliance (Requirement; Compliance)."],"plain_english_summary":"AD/FSM/28 requires operators to inspect certain Hamilton Standard hydro‑mechanical units (HMUs) on specified Pratt & Whitney and JT engines for fuel leaks and to replace or have repaired affected units as specified. Initial visual checks must be done within 30 minutes of shutdown and repeated every 10 flight hours until the HMU is repaired or replaced, with mandatory repair/replacement at the next engine shop visit.\n\nThis directive affects aircraft operators, maintenance organisations and Hamilton Standard service/repair providers because it creates recurring inspection work and a mandatory shop‑visit action to eliminate a possible fuel‑leak hazard."}},"importantCases":[],"_links":{"self":"/api/acts/ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection","history":"/api/acts/ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection/history","analysis":"/api/acts/ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection/analysis","conflicts":"/api/acts/ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection/conflicts","importantCases":"/api/acts/ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection/important-cases","documents":"/api/acts/ad-fsm-28-hamilton-standard-jfc118-fuel-leak-inspection/documents"}}