{"id":"F2005L04152","name":"AD/INST/53 - Shadin ADC-2000 Units","slug":"ad-inst-53-shadin-adc-2000-units","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":40171,"registerId":"commonwealth-F2005L04152-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Instruments and Automatic Pilots","sectionType":"division","heading":"Instruments and Automatic Pilots","content":"### Instruments and Automatic Pilots\n\n| AD/INST/53 | Shadin ADC-2000 Units | 2/2006 DM |\n| ---------- | --------------------- | --------- |\n\n```html\n

Applicability:

Shadin ADC-2000 air data computers (ADC), part numbers (P/N) 962830A-1-S-8, 962830A-2-S-8 or 962830A-3-S-8, Configurations B, C and D.

Note 1: ADC-2000 ADCs are known to be installed in, but not limited to, the following aircraft:

Manufacturer

Alliance Aircraft Group, LLC
B-N Group Ltd
Bombardier Inc
Cessna Aircraft Company

de Havilland Inc
The New Piper Aircraft, Inc

Model

H-250
BN2A
DHC-3, DHC-6
172, 180, 180E, 185, 206, 206E, 206F, 206G 208, 210L, 310
DHC-2
PA-28-180, PA-28-181, PA-31-350,
PA-32-300, PA-32-301, PA-32R-300,
PA-34-200T

Requirement:

1. Perform a pre-flight check in accordance with Paragraph E - Interim Procedures of Shadin Service Bulletin SB28–05–002, Rev C, dated 29 June 2005 to ensure the ADC and the Electronic Flight Information System (EFIS) altimetry accuracy (ie the altitudes, altimeter and elevation do not differ by more than 75 feet).

Requirement 1 may be performed by pilot, other than a student pilot, endorsed on the type. The requirement to perform a pre-flight check in accordance with this Directive is to be entered on the Maintenance Release in the Maintenance Required Section and compliance is to be certified before each flight.

2. If, as a result of the Requirement 1 check, the required altimetry accuracy is not confirmed, install a placard with letters at least 6mm (0.25 in) high in clear view of the pilot stating:

“FLIGHT IN IMC OR UNDER IFR NOT PERMITTED”

3. Return all affected ADCs to the Shadin Repair Facility for upgrade.

\n```\n\n| | Note 2: Contact the Shadin Technical Support Department for a Return Merchandise Authorization (RMA) number before returning the ADC. |\n| ----------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| | Until the ADC-2000 is modified, returned and reinstalled, the aeroplane may only be flown if minimum equipment requirements for that aeroplane are still met. Once the upgraded ADC has been reinstalled the Requirement 2 placard may be removed. |\n| | 4. Shadin ADC-2000, P/N 962830A-1-S-8, 962830A-2-S-8 or 962830A-3-S-8, Configurations B, C, and D, may not be installed on any aeroplane either as an initial installation or as a replacement spare unless it has been upgraded as specified in Requirement 2. |\n| | Note 3: FAA AD 2005-25-08 Amdt 39-14401 refers. |\n| Compliance: | For Requirement 1 - Within the next 25 hours time-in-service (TIS) the effective date of this Directive and thereafter before each flight until the ADC is upgraded as specified Requirement 3. |\n| | For Requirement 2 - Before further flight after the ADC fails the Requirement 1 altimetry accuracy check. |\n| | For Requirement 3 - Within 15 months after the effective date of this Directive. |\n| | For Requirement 4 - As of the effective date of this Directive. |\n| | This Airworthiness Directive becomes effective on 23 January 2006. |\n| Background: | The United States FAA has received reports that certain ADC-2000 units display incorrect altitude information on the EFIS to the pilot. The display of incorrect altitude could cause the flight crew to react to this incorrect flight information and possibly result in an unsafe operating condition. |\n\n![](image.001.png) \nCharles Lenarcic \nDelegate of the Civil Aviation Safety Authority\n\n16 December 2005","sortOrder":0},{"sectionNumber":"AD/INST/53","sectionType":"part","heading":"AD/INST/53","content":"## AD/INST/53","sortOrder":1},{"sectionNumber":"Shadin ADC-2000 Units","sectionType":"part","heading":"Shadin ADC-2000 Units","content":"## Shadin ADC-2000 Units","sortOrder":2},{"sectionNumber":"2/2006 DM","sectionType":"part","heading":"2/2006 DM","content":"## 2/2006 DM","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive addressing a specific safety defect in a specific avionics component. The scope remains tightly focused on the Shadin ADC-2000 altitude display issue as originally identified."},"complexity_factors":["Single-purpose instrument with clear mechanical requirements (checks, placards, returns)","Only 4 numbered requirements with straightforward conditional logic (if check fails, then placard)","Limited cross-referencing (only references one Shadin Service Bulletin and one FAA AD)","Specific part numbers and aircraft models listed explicitly rather than through defined terms","Clear compliance deadlines (25 hours TIS, before further flight, 15 months, immediate)","No nested exceptions or complex interpretation sections"],"plain_english_summary":"This CASA Airworthiness Directive targets aircraft fitted with certain Shadin ADC-2000 air data computers that can display incorrect altitude. It requires operators to verify altitude accuracy before flight, ground unapproved units from IMC/IFR use, and return affected units to Shadin for upgrade, preventing new installations of un‑upgraded units.\n\nIt affects many common light aircraft (Cessna, Piper, de Havilland types) and matters because erroneous altitude readings can lead to dangerous decisions, especially in instrument or poor‑visibility conditions."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The Directive targets the specified Shadin ADC‑2000 part numbers and configurations and units installed across multiple aircraft types. It adds pre‑flight checks, a failure placard and an obligation to return units to Shadin for upgrade, and prohibits installation of non‑upgraded units. It does not broaden applicability to other ADC models beyond the listed ADC‑2000 P/Ns and configurations."},"complexity_factors":["Technical tolerance specified (altimetry agreement within 75 ft) requiring precise checks","Multiple distinct actions with separate compliance timelines (immediate checks, placard before further flight on failure, upgrade within 15 months, installation prohibition as of effective date)","Delegation of routine compliance to pilots (non‑student, type‑endorsed) combined with required maintenance‑release entry and certification","Logistics and supplier coordination: mandatory return to Shadin Repair Facility and RMA process","Operational constraint tying airworthiness to minimum equipment rules and IFR/IMC prohibition when checks fail","Cross‑reference to a manufacturer service bulletin (SB28‑05‑002 Rev C) and an external FAA AD, creating dependency on external documents","Applicability language listing specific part numbers/configurations but noting units are installed across multiple aircraft types"],"plain_english_summary":"This Airworthiness Directive covers Shadin ADC‑2000 air‑data computers (P/Ns 962830A‑1/2/3‑S‑8, Configurations B–D). It requires operators to perform a pre‑flight altimetry check (per Shadin SB28‑05‑002 Rev C) ensuring the ADC and EFIS altitude agree within 75 ft; if the check fails, a cockpit placard bans flight in IMC/under IFR.\n\nAffected units must be returned to Shadin for upgrade within 15 months and may not be installed as spares until upgraded. Pilots/operators must certify checks before flight and follow the RMA/repair process; the Directive responds to FAA reports of incorrect altitude displays."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-inst-53-shadin-adc-2000-units","history":"/api/acts/ad-inst-53-shadin-adc-2000-units/history","analysis":"/api/acts/ad-inst-53-shadin-adc-2000-units/analysis","conflicts":"/api/acts/ad-inst-53-shadin-adc-2000-units/conflicts","importantCases":"/api/acts/ad-inst-53-shadin-adc-2000-units/important-cases","documents":"/api/acts/ad-inst-53-shadin-adc-2000-units/documents"}}