{"id":"F2006B03091","name":"AD/B747/19 - Lightning Protection of Fuel System - Modification","slug":"ad-b747-19-lightning-protection-of-fuel-system-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42463,"registerId":"commonwealth-F2006B03091-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/19 - Lightning Protection of Fuel System - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Boeing 747 Series Aeroplanes\n\n \n\nAD/B747/19 Lightning Protection of Fuel System - Modification 12/79\n\nApplicability: All models.\n\n \n\nDocument: 1. FAA AD 79-20-11, Amdt. 39-3583; or\n\n \n\n2. Boeing SBs 747-28-2068 Rev. 3, 747-28-2069 Rev. 1 and 747-28-2084, Rev. 1.\n\n \n\nCompliance: Before 31 January 1981.\n\n \n\nBackground: A review of the effects of lightning strikes to the B747 aeroplane over a 4-5 year period has prompted modifications to ensure a positive electrical path to ground to voltages that may occur due to a lightning strike to the aeroplane.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive with a single purpose. There is no indication of scope creep; it addresses one specific technical issue (lightning protection) for one aircraft type with a clear compliance deadline that has long since passed."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 4 defined elements: applicability, document references, compliance date, and background","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","No conditional logic or exceptions — applies to all models with a single compliance deadline","Single, clear action required (modification per specified technical documents)"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific repairs or modifications to aircraft.\n\n**What it does:** It orders all Boeing 747 operators to modify the fuel system to improve protection against lightning strikes. Specifically, aircraft must be fitted with modifications that ensure electricity from a lightning strike can safely travel to \"ground\" (the aircraft's frame) rather than building up dangerous voltages in the fuel system.\n\n**Who it affects:** Anyone operating any model of Boeing 747 aircraft in Australia.\n\n**Why it matters:** Lightning strikes can generate massive electrical voltages. Without proper protection, this electricity could spark in or near the fuel system — with potentially catastrophic consequences (fire or explosion). This AD was issued after a 4-5 year review showed the existing protection was inadequate.\n\n**What must be done:** Operators must follow specific Boeing service bulletins (technical instructions) or the equivalent US FAA directive, and complete the work before 31 January 1981."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive's scope, as stated in the text provided, is to require lightning-protection modifications to the fuel system of all Boeing 747 models and to specify the acceptable compliance documents and a completion date. The background explains this follows a 4–5 year review and the directive limits acceptable compliance methods to the listed FAA AD or Boeing service bulletins (see \"Applicability\", \"Document\", \"Compliance\", \"Background\"). The text contains no indication that the scope diverges from this stated purpose."},"complexity_factors":["Cross-reference to external technical documents (FAA AD and multiple Boeing Service Bulletins) increases compliance coordination (see \"Document\").","Firm calendar deadline requires scheduling and possible aircraft downtime (see \"Compliance\").","Technical nature of the required modification (electrical path to ground for lightning voltages) requires specialised maintenance personnel and facilities (implied by \"Background\").","Applicability to all models expands the population of affected aircraft but does not differentiate by variant or configuration (see \"Applicability\").","Directive provides specific compliance methods, limiting alternative compliance paths and increasing procedural rigidity (see \"Document\")."],"plain_english_summary":"Requires all Boeing 747 operators to install a specified fuel‑system lightning‑protection modification, completed by 31 January 1981, using one of the listed FAA or Boeing documents. Issued by CASA after a multi‑year lightning review to ensure the airplane provides a positive electrical path to ground; costs, downtime and compliance responsibility fall to owners/operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-19-lightning-protection-of-fuel-system-modification","history":"/api/acts/ad-b747-19-lightning-protection-of-fuel-system-modification/history","analysis":"/api/acts/ad-b747-19-lightning-protection-of-fuel-system-modification/analysis","conflicts":"/api/acts/ad-b747-19-lightning-protection-of-fuel-system-modification/conflicts","importantCases":"/api/acts/ad-b747-19-lightning-protection-of-fuel-system-modification/important-cases","documents":"/api/acts/ad-b747-19-lightning-protection-of-fuel-system-modification/documents"}}