{"id":"F2006B05721","name":"AD/PA-31/15 - Alternator Field Fuse - Installation","slug":"ad-pa-31-15-alternator-field-fuse-installation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":135520,"registerId":"commonwealth-F2006B05721-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-31/15 - Alternator Field Fuse - Installation","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)  \nPiper PA-31 Series Aeroplanes\n\nAD/PA-31/15 Alternator Field Fuse \\- Installation 3/71\n\nApplicability: All models fitted with a voltage regulator selector switch.\n\nRequirement: 1. In PA-31 aircraft fitted with a Delco Remy 50 amp alternator system, install a 3 amp fuse in each field circuit between the “F” field terminal on the alternator and the alternator main circuit breaker (i.e. Cable PF13EE and in cable PF12EE).\n\n    2. In PA-31 aircraft fitted with a Prestolite 70 amp alternator system, install a 3 amp fuse in each field circuit between the “F” field terminal on the alternator and the junction point of cables PF34EF and PF33EE inboard of the wing root terminal strips. (i.e. Cable PF21EA or PF33EE and in cable PF22FB or PF34EF).\n\n    3. In PA-31P aircraft install a 3 amp fuse in each field circuit between the voltage regulator selector switch and the alternator control switches (i.e. Cable PF28 or PF33 and in cable PF39 or PF32).\n\nNote: It is not necessary for these fuses to be accessible in flight.\n\n    4. Functionally check the alternator system and the adjustment of the voltage regulators as per the manufacturer’s service manual.\n\nCompliance: Within 200 hours time in service after 31 March 1971.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1249},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow, technical scope targeting a specific electrical safety modification for specific Piper aircraft models. It has not expanded beyond the original intent of mandating fuse installation in alternator field circuits."},"complexity_factors":["Technical aviation terminology requiring knowledge of electrical systems (alternator field circuits, voltage regulators, terminal strips)","Three distinct implementation paths depending on specific alternator model installed (Delco Remy 50 amp vs Prestolite 70 amp vs PA-31P)","Precise cable reference numbers requiring technical diagrams (PF13EE, PF12EE, PF34EF, etc.)","External cross-reference to manufacturer service manual for functional testing procedures","Non-standard compliance metric (flight hours 'time in service' rather than calendar date)"],"plain_english_summary":"This mandatory safety directive requires owners/operators of Piper PA-31 aircraft fitted with a voltage regulator selector switch (including those with Delco Remy 50A or Prestolite 70A alternators and PA-31P models) to install 3‑amp fuses in the alternator field circuits and verify alternator/voltage regulator operation. \n\nThe modification prevents overheating, fire, or electrical failure in flight; work must be completed within 200 flight hours after March 31, 1971."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-31-15-alternator-field-fuse-installation","history":"/api/acts/ad-pa-31-15-alternator-field-fuse-installation/history","analysis":"/api/acts/ad-pa-31-15-alternator-field-fuse-installation/analysis","conflicts":"/api/acts/ad-pa-31-15-alternator-field-fuse-installation/conflicts","importantCases":"/api/acts/ad-pa-31-15-alternator-field-fuse-installation/important-cases","documents":"/api/acts/ad-pa-31-15-alternator-field-fuse-installation/documents"}}