{"id":"F2006B10835","name":"AD/INST/32 - Altimeters","slug":"ad-inst-32-altimeters","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56316,"registerId":"commonwealth-F2006B10835-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/INST/32 - Altimeters","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/32 Altimeters 5/86\n\nApplicability: United Instruments Inc altimeters 5934 series with the following serial numbers: 6C461 thru 6C999\n\n7C000 thru 7C999\n\n8C000 thru 8C999\n\n9C000 thru 9C999\n\n0D000 thru 0D999\n\n1D000 thru 1D999\n\n2D000 thru 2D869\n\nmanufactured between 1 February 1985 and 28 February 1986 and not identified as modified by a 6mm yellow dot on the lower half of the rear case and the letter \"M\" stamped on the data plate just before the word \"altimeter\".\n\nRequirement: Action in accordance with United Instruments Inc SB No. 2.\n\nNote: FAA AD 86-05-02 refers.\n\nCompliance: Prior to issue of the next Maintenance Release after 31 May 1986.\n\nNote: Corrective action MAY be carried out in Australia by an approved workshop and the altimeter appropriately identified.\n\nBackground: Several reports have been received stating that a slight outward pull on the barometric scale setting knob may disconnect the millibar scale from the altitude indication pointers.","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 manufacturing defect in a specific batch of altimeters. It has not expanded beyond its original safety purpose."},"complexity_factors":["Single, specific applicability criteria (one manufacturer, one series, defined serial number ranges, defined manufacturing period)","Simple binary identification test (yellow dot + 'M' stamp = already fixed)","Single compliance action (follow manufacturer's Service Bulletin No. 2)","Single deadline condition (prior to next Maintenance Release after fixed date)","No defined terms section, no cross-references to other legislation beyond a note about the equivalent FAA directive","Background provided in plain narrative form"],"plain_english_summary":"This is a **safety order** issued by Australia's Civil Aviation Safety Authority (CASA) that applies to a specific batch of aircraft altimeters made by United Instruments Inc.\n\n**What it does:**\n- **Targets:** Altimeters from the 5934 series with serial numbers between 6C461 and 2D869, manufactured between February 1985 and February 1986\n- **Identifies the problem:** The barometric pressure setting knob can disconnect from the altitude pointer if pulled slightly outward — meaning pilots could get wrong altitude readings\n- **Requires:** Owners/operators must get the altimeter fixed according to the manufacturer's Service Bulletin No. 2\n- **Deadline:** Before the aircraft's next Maintenance Release is issued after 31 May 1986\n- **Good news:** The repair can be done in Australia at an approved workshop, and the fixed altimeters get marked with a yellow dot and an \"M\" stamp so you can tell they've been corrected\n\n**Why it matters:** Faulty altimeters can give pilots incorrect altitude readings, which is extremely dangerous — especially during landing or when flying near terrain or other aircraft. This directive ensures potentially defective units are identified and repaired before they cause accidents."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"Scope aligns with the instrument's stated safety objective: it targets only specified serial-numbered altimeters manufactured in the stated period and requires correction per the manufacturer’s service bulletin to remedy the reported mechanical fault; it does not broaden obligations beyond those units."},"complexity_factors":["Very narrow applicability: specific serial-number ranges and manufacture dates require verification of individual altimeters.","Identification requirement: altimeters are excluded if marked by a 6mm yellow dot and an \"M\" on the data plate, creating an administrative check.","Single mandatory action references an external document (United Instruments SB No. 2), so compliance depends on that manufacturer's instructions.","Compliance timing tied to the operator's next Maintenance Release after a fixed date (31 May 1986), combining a calendar and procedural trigger.","Permits corrective work by approved Australian workshops, introducing oversight and approval processes for who may perform the fix.","Cross-reference to FAA AD 86-05-02 links domestic compliance to an overseas airworthiness directive, creating an international regulatory dependence.","Underlying technical fault is mechanical (knob pull disconnects millibar scale from pointers), so the remedy is hardware inspection/repair rather than operational restriction."],"plain_english_summary":"Requires specific United Instruments 5934-series altimeters (listed serial ranges manufactured 1 Feb 1985–28 Feb 1986 and not marked as modified) to be inspected/modified per United Instruments Service Bulletin No. 2 because a slight pull on the barometric scale knob may disconnect the millibar scale from the altitude pointers. Aircraft operators must have the corrective action completed before the next Maintenance Release after 31 May 1986; approved Australian workshops may perform the work, so operators bear the compliance cost."}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-32-altimeters","history":"/api/acts/ad-inst-32-altimeters/history","analysis":"/api/acts/ad-inst-32-altimeters/analysis","conflicts":"/api/acts/ad-inst-32-altimeters/conflicts","importantCases":"/api/acts/ad-inst-32-altimeters/important-cases","documents":"/api/acts/ad-inst-32-altimeters/documents"}}