{"id":"F2006B10821","name":"AD/INST/2 Amdt 2 - Edison and Garwin Engine Gauge Units - Modification","slug":"ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56299,"registerId":"commonwealth-F2006B10821-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/INST/2 Amdt 2 - Edison and Garwin Engine Gauge Units - Modification","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)  \nInstruments and Automatic Pilots\n\nAD/INST/2\n\nAmdt 2\n\n  \n\nEdison and Garwin Engine Gauge Units \\- Modification\n\n  \n5/66\n\nApplicability: Thomas A. Edison engine gauge units models 195, 273 and military models AN5773- 1A or T1A, AN5773-2 or -T2, MS28043-1 or -T1 and MS28043-2 or -T2\n\nmanufactured prior to 30 June 1962; and also Garwin Inc. engine gauge units P/N 22- 802-03 thru -14 and 22-802-022 with date stamp before 1 April 1962.\n\nRequirement: 1. Modify gauge units by replacing the diaphragm and capillary tube assembly P/N 45010 with a new assembly P/N 45010. The new assemblies are identified with a 1/4 in. wide white band painted on the capillary tube adjacent to the solder joint of the tube to the diaphragm.\n\n2. Provide an overboard drain line from the fuel pressure gauge vent connection on each gauge unit installation. The line shall be terminated at a point where the discharge of fuel will not constitute a fire hazard and where fumes will not enter personnel compartments.\n\nCompliance: Before 31 November 1966.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, targeted airworthiness directive addressing a specific safety defect in specific aircraft components. It has not expanded beyond its original purpose of mandating safety modifications to Edison and Garwin engine gauge units."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 specific technical requirements","Clear applicability section listing exact model numbers and date ranges","Single compliance deadline","No defined terms section","No cross-references to other legislation","No conditional logic or exceptions"],"plain_english_summary":"Australia's Civil Aviation Safety Authority issued a safety directive requiring operators of older Thomas A. Edison and Garwin Inc. engine gauge units to replace a faulty diaphragm/capillary assembly with an improved, white‑band marked unit and install a drain line to vent fuel away from passengers and ignition sources. It targets specified Edison models (including 195 and 273) built before 30 June 1962 and listed Garwin part numbers dated before 1 April 1962 to prevent fuel leaks and fire hazards."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This instrument is titled as Amendment 2 to AD/INST/2 and specifies concrete modification obligations: replacement of the diaphragm/capillary assembly (with new assembly identified by a white band) and installation of overboard drain lines for identified gauge units manufactured before specified dates, with a compliance deadline of 31 November 1966. As an amendment, it therefore alters the prior directive by adding these explicit part, identification and installation requirements and the deadline."},"complexity_factors":["Narrow technical scope limited to specific vintage gauge models and part numbers (models 195, 273; multiple military part numbers; P/N 22-802-03 thru -14, 22-802-022)","Use of manufacture/date-stamp cutoffs to determine affected units (prior to 30 June 1962; date stamp before 1 April 1962)","Precise parts-identification requirement (replace P/N 45010 with new P/N 45010 identified by a 1/4 in. white band)","Installation detail for overboard drain line requiring safe termination point (mitigates fire/fume risk)","Fixed compliance deadline (before 31 November 1966) creating a time-bound compliance burden for operators","Work involves physical modification/installation (requires technical labour, possible downtime, and access to replacement parts)"],"plain_english_summary":"This airworthiness directive requires owners/operators of specified Thomas A. Edison and Garwin engine gauge units made before the listed manufacture dates to replace the diaphragm/capillary assembly with a newly identified assembly (marked by a 1/4 in. white band) and to fit an overboard fuel drain line from each fuel pressure gauge vent, routed so discharged fuel and fumes won’t create a fire or enter personnel compartments. Compliance is required before 31 November 1966, and the cost and work fall to aircraft owners/operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification","history":"/api/acts/ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification/history","analysis":"/api/acts/ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification/analysis","conflicts":"/api/acts/ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification/conflicts","importantCases":"/api/acts/ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification/important-cases","documents":"/api/acts/ad-inst-2-amdt-2-edison-and-garwin-engine-gauge-units-modification/documents"}}