{"id":"F2006B10826","name":"AD/INST/24 - Filotecnica Salmoiraghi Airspeed Indicators - Calibration Tests","slug":"ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56304,"registerId":"commonwealth-F2006B10826-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/INST/24 - Filotecnica Salmoiraghi Airspeed Indicators - Calibration Tests","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 - 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Instruments and Automatic Pilots\n\n \n\n# AD/INST/24 Filotecnica Salmoiraghi Airspeed Indicators - Calibration Tests\n\nApplicability: Airspeed indicators S/No. 0001 to 3800 with P/No. 8.039.003, 8.039.008,\n\n# 12/77\n\n8.039.008.1, 8.039.503, 8.039.508, 8.039.508.1, 8.039.603, 8.039.608, 8.039.608.1,\n\n8.039.703, 8.039.708.1, 8.039.808, 8.039.808.1, 8.039.408 or 8.039.408.1 and\n\n8.039.708.\n\n \n\nDocument: 1. FAA AD 77-15-10; or\n\n \n\n2. SAE Aeronautical Standard AS 391B pressures and tolerances for airspeed indicator calibration.\n\n \n\nCompliance: Within 100 hours time in service after 31 December 1977.\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-limited safety directive from 1977 addressing a specific technical issue with specific aircraft instruments. It has not expanded beyond its original purpose of mandating calibration tests for the identified airspeed indicators."},"complexity_factors":["Very short document (approximately 200 words)","No defined terms section — all terms are standard aviation terminology","No cross-references to other legislation beyond the enabling regulation (Civil Aviation Regulations 1998, Part 39)","Simple conditional structure: applicability criteria → required action → deadline","Single compliance pathway with two alternative technical standards","No exceptions, exemptions, or nested conditions"],"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) under the Civil Aviation Regulations 1998.\n\n**What it does:** It requires owners and operators of specific Filotecnica Salmoiraghi airspeed indicators (flight instruments that show how fast an aircraft is flying) to have them **calibration tested**.\n\n**Who it affects:** Anyone operating aircraft fitted with these particular airspeed indicators — specifically serial numbers 0001 to 3800 with any of the listed part numbers (such as 8.039.003, 8.039.008, and various others).\n\n**What must be done:** The instruments must be tested to ensure they accurately measure air pressure and display the correct speed, following either:\n- A US Federal Aviation Administration directive (FAA AD 77-15-10), **or**\n- An industry standard (SAE AS 391B) that sets out pressure tolerances for these tests\n\n**When:** The testing must be completed **within 100 hours of flight time** after 31 December 1977.\n\n**Why it matters:** Faulty airspeed indicators can give pilots incorrect speed readings — a serious safety risk that has contributed to accidents. This directive ensures these specific instruments were checked and corrected if found inaccurate."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is narrowly defined in the text: it applies to Filotecnica Salmoiraghi airspeed indicators with serial numbers 0001–3800 and the listed part numbers, and it requires calibration in accordance with one of two referenced documents within a single specified compliance window. The document contains no indication that the applicability or the required action has been broadened or narrowed relative to an earlier or different intent within the text provided."},"complexity_factors":["Narrow, specific applicability (limited serial number range and listed part numbers). (Applicability)","Single, short compliance requirement (one calibration action within a fixed 100-hour window). (Compliance)","Dependence on external technical documents for procedural detail and acceptance criteria (FAA AD 77-15-10 or SAE AS 391B). (Document)","Technical subject matter (calibration tolerances and pressures) requires specialist maintenance capability to implement despite simple regulatory structure. (Document)"],"plain_english_summary":"What this directive does mechanically\n\n- Requires calibration testing of certain Filotecnica Salmoiraghi airspeed indicators. The directive applies to indicators with serial numbers 0001 to 3800 and the listed part numbers (see \"Applicability\"). (Applicability)\n- The tests must be carried out in accordance with one of two technical references: either FAA AD 77-15-10 or SAE Aeronautical Standard AS 391B (pressures and tolerances for airspeed indicator calibration). (Document)\n- The calibration must be completed within 100 hours time in service after 31 December 1977. (Compliance)\n\nWho is affected and who decides\n\n- Affected parties: owners/operators of aircraft that have the specified Filotecnica Salmoiraghi airspeed indicators installed. (Applicability)\n- Decision/authority: the requirement is issued as an airworthiness directive under the Commonwealth/Civil Aviation Safety Authority schedule of directives. Compliance is measured against the two external technical documents referenced. (header; Document)\n\nWho pays and who performs the work\n\n- The directive does not state who pays; practically, aircraft owners/operators will incur the cost of arranging and paying for calibration or any corrective action. The actual work will be done by whoever is qualified to perform the calibration per the referenced standards (maintenance organisation or qualified technician). (Applicability; Document)\n\nCompliance burden, timing and practical effects\n\n- Burden: arranging technical calibration to meet the prescribed pressures and tolerances in the referenced documents, within the specified service-time window. (Document; Compliance)\n- Timing: the compliance window is specified as within 100 hours time in service after 31 December 1977, creating a clear but short window from that anchor date for affected units. (Compliance)\n- Behavioural effect: operators must schedule and document the calibration or take other remedial action (for example replacing non-conforming units) to achieve compliance with the referenced standard. (Applicability; Document)\n\nRationale, trade-offs and implementation risks (source-grounded)\n\n- The directive text itself does not include an explicit statement of rationale. The instrument requires calibration to the technical limits set out in FAA AD 77-15-10 or SAE AS 391B. (Document)\n- Trade-offs and costs that follow mechanically from the requirement in the text: calibration imposes direct financial cost and aircraft downtime on owners/operators; complying requires access to the referenced technical materials and qualified maintenance capability; non-compliant units may require further corrective action or replacement. (Applicability; Document; Compliance)\n- Implementation risks and practical issues arising from the text: the directive relies on two external, technical documents for the detailed procedure and acceptance criteria, so obtaining and interpreting those documents is necessary to demonstrate compliance; the specified compliance anchor date may create record-keeping or scheduling complexities for operators calculating the applicable 100-hour window. (Document; Compliance)\n\nDiscretion and enforcement\n\n- The directive is prescriptive about which documents set the technical standard (FAA AD or SAE AS 391B) and gives a fixed compliance window; the text does not create discretion to change the technical acceptance criteria within the directive itself. (Document; Compliance)\n\nNet mechanical effect\n\n- Owners/operators of aircraft fitted with the listed Filotecnica Salmoiraghi airspeed indicators must have those indicators tested and calibrated to one of the two referenced technical standards within the stated 100-hour window after 31 December 1977; evidence of compliance will depend on following the referenced documents' procedures and tolerances. (Applicability; Document; Compliance)\n"}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests","history":"/api/acts/ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests/history","analysis":"/api/acts/ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests/analysis","conflicts":"/api/acts/ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests/conflicts","importantCases":"/api/acts/ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests/important-cases","documents":"/api/acts/ad-inst-24-filotecnica-salmoiraghi-airspeed-indicators-calibration-tests/documents"}}