AD/INST/49 Amdt 1 - Rockwell Collins Air Data Computers

The AD centres on three principal operational and technical concepts: identification of affected hardware, mandatory corrective work at the unit/component level, and an installation prohibition for unmodified units. Identification of affected hardware is supplied by an explicit Applicability table that lists unit names, part numbers and serial-number criteria. That table identifies unit families ADC-85, ADC-85A and ADC-850 (various suffixes) and enumerates part numbers such as 622-8051-002, 822-0370-113, 822-0389-133 and 822-1036-406. The applicability also includes a serial-number caveat for ADC-850D, described as "All up to and including 3DGW (except for 1P6D, 22RC-22RF and 23WK-3DGP)", a precise identification method that determines which physical units fall within the directive.

The mandatory corrective work is set out in Requirement 1 and has three discrete steps as phrased in the AD: remove any affected ADC from the aeroplane; replace or reprogram parts or circuit card assemblies on central processing unit (CPU) circuit cards as applicable; and test the ADC. The AD prescribes the technical standards for that work by reference to Rockwell Collins SB 62, either the Revision No. 2 dated 7 March 2000 or the SB dated 25 October 1999 as applicable, together with the Collins Computer Component Maintenance Manual and Collins Avionics Standard Shop Practices Instruction Manual. The AD thus delegates the detailed technical method to manufacturer documentation rather than specifying low-level test procedures in the AD text.

The installation prohibition is Requirement 2. It forbids installation of affected ADCs on any aeroplane, except Saab 340 series aeroplanes, unless the modification and testing required by Requirement 1.b and 1.c have been accomplished. That prohibition functions as a supply-side control over the aircraft parts market and over maintenance practices: until the CPU circuit cards have been reprogrammed or replaced and the ADC tested, units cannot be reinstalled on aircraft other than the identified Saab 340 exception.

Supplementary concepts appear in the AD notes. Note 2 recommends temporary installation of an operational placard per Rockwell Collins Operator Bulletin 99-7 until AD actions are achieved; CASA describes that placard as not necessary to address the unsafe condition in the Directive but highly recommends it. Note 3 cross-references FAA materials, signalling parallel activity or related advisory material in the US regulatory environment. The Background section describes the operational failure mode that motivated the AD: an unwarranted ADC flag triggered by the Normal/Alternate Air static source selection capability, discovered during flight testing.

Mechanically, the AD is issued under subregulation 39.1(1) of CASR 1998 and revokes the prior AD/INST/49, replacing it with this amended instrument. The AD records key dates: the original AD became effective 5 September 2002, the amendment becomes effective 12 June 2003, and the delegate signed on 1 May 2003 with notification in the Commonwealth Gazette on 21 May 2003. These temporal anchors determine the compliance windows stated in the Compliance section.

The AD imposes obligations on owners and operators of aeroplanes that have the listed Rockwell Collins ADC units installed. The Applicability section lists ADC models, part numbers and serial-number ranges by unit type, therefore providing a mechanical rule for inclusion: any aeroplane with an ADC matching those identifiers is within scope unless an express carve-out applies. The AD expressly excepts ADC-85A units, part numbers 822-0370-113 or -123, that have Rockwell Collins Service Bulletin 58 incorporated and that are installed on Saab 340 series aeroplanes. That exception narrows the affected population to exclude a defined set of Saab 340 installations that already incorporate SB 58.

Maintenance organisations and licensed avionics shops also face an operational impact. Requirement 1 requires removal from the aeroplane, replacement or reprogramming of CPU circuit card parts or assemblies, and subsequent testing of the ADCs in accordance with Rockwell Collins SB 62 and the Collins maintenance and shop-practices manuals. Those instructions rely on shop-level capabilities, specialised tooling and access to manufacturer documentation. The AD thus affects the service providers who will perform the technical work and certify the tests. The AD requires that applicable modifications and tests be recorded and completed before reinstallation on aeroplanes other than Saab 340s, so record-keeping and traceability fall to operators and maintenance organisations.

Supply-chain actors are implicated indirectly. Requirement 1.b contemplates replacement of parts or circuit card assemblies, which creates demand for replacement components, reprogrammed CPU cards, or Rockwell Collins-supported rework services. The AD does not specify whether Rockwell Collins will supply reprogrammed assemblies or parts, but the operator must ensure compliance with the SB 62 procedures. Aircraft registrants and operators therefore bear the economic cost of parts, labour and aircraft downtime. The AD’s installation prohibition (Requirement 2) reduces the set of ADC units available for reinstallation until they have been modified and tested, which may affect parts interchangeability and inventory management for operators and spares suppliers.

Regulatory and oversight actors are affected in administrative terms. CASA is the issuing authority under CASR 1998 subregulation 39.1(1), and the instrument records the delegate’s signature and the Gazette notification date. The AD also references FAA materials (FAA AD 2002-14-19 and FAA SAIB CE-03-21) and a Rockwell Collins Operator Bulletin; these cross-references indicate that other regulators and OEM advisory materials are part of the compliance and information landscape.

Finally, crewmembers and flight operations are indirectly affected by the AD because the Background explains that an unwarranted ADC flag could lead flight crews to react to incorrect flight information. Note 2 recommends installation of an operational placard per Operator Bulletin 99-7 until corrective actions are complete; CASA states the placard is not necessary to address the unsafe condition but highly recommends it. That recommendation creates an operational mitigation that operators may choose to adopt pending parts-level compliance.

The AD establishes specific duties for operators, maintainers and those deciding whether to install affected units. The principal duties flow from the Requirement section.

Duty to remove the unit: Requirement 1.a requires removal of any affected ADC from the aeroplane. That duty places responsibility on the operator or maintenance organisation to identify affected units by cross-checking part numbers and serial numbers listed in the Applicability table and to physically remove those units for corrective action.

Duty to replace or reprogram CPU parts: Requirement 1.b mandates, "as applicable, replace or reprogram parts or circuit card assemblies on central processing unit (CPU) circuit cards." The duty is conditional on the unit’s configuration and on the procedures in Rockwell Collins SB 62. The AD ties the acceptable methodology to the SB and to Collins manuals, thereby making conformity with those documents the de facto standard for satisfying the duty.

Duty to test: Requirement 1.c requires testing of the ADC following replacement or reprogramming. The AD specifies that testing must be carried out in accordance with SB 62 and the Collins manuals. The duty therefore includes not only mechanical or software work but validation steps set by the manufacturer documents.

Installation prohibition: Requirement 2 prohibits installation of affected ADCs on any aeroplane, except Saab 340 series aeroplanes, unless the modification and tests mandated by Requirement 1.b and 1.c have been completed. This creates a preventative duty or negative obligation: operators and installers must verify that the modification and testing have occurred before installation.

Temporal duties: The Compliance section preserves the original compliance timing for Requirement 1 as "Within 12 months after the effective date of the original issue of this Directive." That duty imposes a temporal limit within which operators must accomplish removal, replacement/reprogramming and testing. Requirement 2 is effective as of the amendment date, meaning that, from the amendment effective date, affected ADCs cannot be installed unless modified and tested.

Recommendation (not mandatory) regarding placard: Note 2 refers to Rockwell Collins Operator Bulletin 99-7, which contains information about an operational placard to install until accomplishment of the Directive’s actions. CASA states that the placard is "not necessary to address the unsafe condition in this Directive" but "highly recommends" it. The AD therefore distinguishes between mandatory obligations and a strongly recommended interim operational mitigation.

Rights and discretion embedded in the instrument: The AD does not describe a rights regime for relief, equivalent substitutions or alternative methods of compliance within its text. It does prescribe the applicable SBs and manuals for the work, thereby limiting the allowed methods to those manufacturer documents, unless elsewhere a regulatory mechanism for alternative compliance is used (not stated in the AD text). CASA issued and signed the amendment; the AD records the delegate's action under CASR 1998 subregulation 39.1(1), reflecting that the regulatory decision rests with CASA as the issuing authority.

Record and trace obligations: While the AD itself does not recite administrative-recordkeeping requirements beyond the testing and modification steps, operators will need to maintain compliance evidence to demonstrate that removal, modifications or reprogramming and testing were performed in line with the specified SB and manuals, particularly due to the installation prohibition. The AD links compliance to specific technical documents rather than to an open-ended engineering standard.

The AD is promulgated under the authority of subregulation 39.1(1) of CASR 1998 and is signed by the CASA delegate, which places responsibility for compliance on operators and maintainers in the Australian regulatory framework. The instrument itself sets out mandatory actions (Requirement 1) and a prohibition (Requirement 2), together with compliance timings: Requirement 1 remains "Within 12 months after the effective date of the original issue of this Directive" and Requirement 2 is effective as of the amendment's effective date (noted as 12 June 2003). The AD was notified in the Commonwealth of Australia Gazette on 21 May 2003.

The AD does not include an express schedule of criminal or civil penalties within its text. It is an instrument that prescribes corrective actions and installation restrictions for specified aircraft equipment. Enforcement mechanisms ordinarily flow from CASA’s regulatory powers under CASR 1998, which is the statutory framework referenced in the AD’s opening paragraph; the AD itself identifies the statutory basis by naming subregulation 39.1(1). The AD’s notification and gazettal provide public notice of the requirements and the effective dates, which supports regulatory compliance monitoring or oversight by CASA.

Operational enforcement follows from the AD’s mechanics. Requirement 2 effectively creates a prohibition on installing affected ADCs on aeroplanes other than Saab 340 series unless they have been modified and tested as required by Requirement 1.b and 1.c. Maintenance organisations and installers are therefore required to verify the modification and test state of an ADC prior to installation; failure to do so would leave an unmodified unit installed in breach of the AD. Similarly, operators who do not remove, reprogram/replace or test affected units within the compliance window set out in Requirement 1 would be out of step with the Directive’s mandatory requirements.

The AD cross-references related FAA materials, including FAA AD 2002-14-19 Amdt 39-12819 and FAA Special Airworthiness Information Bulletin CE-03-21, which indicates that parallel or complementary enforcement and advisory activity exists in the FAA sphere, although those references are advisory within this instrument. Note 2’s recommendation to install an operational placard per Rockwell Collins Operator Bulletin 99-7 is described as recommended rather than mandatory; CASA states the placard is not necessary to address the unsafe condition but "highly recommends" it. That distinction affects enforcement: the placard is a mitigant suggested by CASA but not an enforceable part of the Directive.

Because the AD does not itself list sanctions, the practical enforcement pathway will be regulatory oversight and compliance checks by CASA, and potential regulatory action under CASR 1998 where non-compliance is discovered. The AD’s gazettal and the delegate’s signature establish public record of the requirements and dates, which are relevant to any enforcement or administrative follow-up.

The AD is an instrument issued under Australian aviation regulation and explicitly cites the statutory basis for issuance: subregulation 39.1(1) of CASR 1998. By referencing that subregulation, the AD situates itself as an administrative directive made under the Civil Aviation Safety Regulations framework. The AD revokes the former AD/INST/49 and replaces it with the amended requirements; that revocation is internal to the AD instrument and affects the statutory obligations that flowed from the earlier directive.

The AD also cross-references non-Australian materials. Note 3 refers to FAA AD 2002-14-19 Amdt 39-12819 and FAA Special Airworthiness Information Bulletin CE-03-21. Those references indicate that the FAA has issued related materials addressing the same or similar unsafe condition. The AD’s Background records advice from the United States Federal Aviation Administration that Saab 340 series aeroplanes were not affected, which is the basis for the carve-out in the Applicability section. The cross-references and the FAA advice show where foreign regulatory findings have influenced the AD’s scope, but the AD itself frames compliance obligations in domestic terms via CASR subregulation 39.1(1).

The AD relies substantively on manufacturer documentation: Rockwell Collins SB 62 (either Revision No. 2, dated 7 March 2000, or the SB dated 25 October 1999, as applicable), the Collins Computer Component Maintenance Manual and Collins Avionics Standard Shop Practices Instruction Manual. That reliance creates a practical interaction between regulatory obligations and private standards set by the original equipment manufacturer. Compliance with the AD requires following those manufacturer documents, so the AD creates a bridge between regulator-mandated actions and manufacturer-prescribed technical methods.

Operational safety documentation from Rockwell Collins is referenced in Note 2, Rockwell Collins Operator Bulletin 99-7, which contains information about an operational placard recommended until implementation of the AD’s actions. CASA states the placard is not necessary to address the unsafe condition but highly recommends it, so the AD creates a formal-but-non-mandatory link to that operator bulletin.

The AD’s installation prohibition (Requirement 2) alters permissible maintenance and installation decisions under the broader airworthiness regime by making the modified state of a component a precondition to installation. That interacts with maintenance approvals, parts traceability and continuing airworthiness obligations because an organisation that installs an ADC must ensure the precondition is met. The AD does not itself lay out recordkeeping or certification formalities but interacts with those obligations insofar as maintenance organisations must be able to demonstrate that the required modification and testing were carried out in accordance with the specified SB and manuals.

Finally, the AD’s gazettal on 21 May 2003 and the recorded effective date of 12 June 2003 establish temporal relations with other legal or contractual obligations (for example, maintenance schedules, lease obligations or aircraft operations), but the AD text does not elaborate on priority of norms beyond citing CASR subregulation 39.1(1) as the authority for the Directive.

This instrument is titled AD/INST/49 Amdt 1 and explicitly revokes the prior AD/INST/49. The AD records a sequence of events and dates that constitute its amendment history. The original issue of AD/INST/49 became effective on 5 September 2002, as stated in the Background. The amendment process culminated in the delegate signing the amendment on 1 May 2003; the AD notes that the amendment becomes effective on 12 June 2003, and it was notified in the Commonwealth of Australia Gazette on 21 May 2003. The AD’s Compliance section preserves the original compliance interval for Requirement 1 as "Within 12 months after the effective date of the original issue of this Directive", which indicates continuity with the original timing despite the amendment.

Substantive content changed by the amendment is limited and recorded in the AD text. The Background explains that the original directive required replacement of affected ADCs with units that had a reprogrammed and tested CPU circuit card and circuit card assembly, following flight test evidence that the ADCs could display an unwarranted ADC flag in response to the aeroplane's Normal/Alternate Air static source selection capability. The amendment arose after advice from the United States Federal Aviation Administration that Saab 340 series aeroplanes were not affected. That advice prompted the inclusion of an exception for Saab 340 installations where SB 58 had been incorporated on ADC-85A part numbers 822-0370-113 or -123. The amended AD therefore narrows applicability relative to the original directive insofar as certain Saab 340 installations are excluded.

The AD retains cross-references to Rockwell Collins SB 62 and to Collins manuals as the operative technical measures for correction. The AD provides both the Revision No. 2 dated 7 March 2000 and the earlier SB dated 25 October 1999 as applicable alternatives for compliance. The amendment’s effective date (12 June 2003) makes Requirement 2 effective as of that date; Requirement 1’s compliance timing remains aligned with the original issue’s effective date.

Administrative dates are explicit: the delegate signed on 1 May 2003, the AD was gazetted on 21 May 2003 and the amendment was effective 12 June 2003. The AD therefore documents the amendment process in a compact set of temporal markers and records the rationale for the change (FAA advice that Saab 340 series aeroplanes were not affected). The AD also notes that the original issue was prompted by flight test findings; that operational origin remains part of the documented history.

The AD text does not record any litigation history or reference any judicial or administrative decisions challenging the directive. It cites no cases, proceedings, or dispute-resolution outcomes. The Background traces the technical and inter-regulatory genesis of the AD, noting that it followed a flight test that showed a potential malfunction and that the amendment followed advice from the United States Federal Aviation Administration that Saab 340 series aeroplanes were not affected. That narrative is technical and administrative; it does not record any adjudicative or litigious follow-on.

Because the instrument itself contains no litigation references, anyone seeking adjudication-related materials or judicial interpretations would need to consult external case law databases, tribunal records or administrative review filings, none of which are referenced in this AD. The AD records that it was notified in the Commonwealth of Australia Gazette on 21 May 2003, which creates a public record of the directive and its effective dates; however, the AD does not state whether any administrative appeals or legal challenges were made against either the original AD/INST/49 or this amendment.

For compliance and risk management purposes, the absence of litigation references in the AD means that the text itself is the primary source for understanding obligations, timing and technical standards. Any question about the AD’s scope, enforceability or interpretation that might otherwise be resolved through litigation will not be illuminated by the AD’s own text. Practitioners requiring information about dispute outcomes or precedent would need to look beyond the AD to records of CASA enforcement actions, administrative appeals, or court proceedings, none of which are supplied in this instrument.

In summary, the AD shows a technical and inter-agency advisory history but contains no litigation history. The amendment was driven by FAA advice and by flight-test findings; no adjudicative matters are mentioned in the AD text.

Several detailed features of the AD create discrete practical pitfalls for operators, maintainers and parts managers. These are concrete attention points where a failure to parse the AD precisely could produce non-compliance or operational disruption.

Narrowly specified applicability: The AD’s Applicability section lists units by model, part number and, in the case of ADC-850D, by serial-number range with specific carve-outs. For example, ADC-850D is listed as "All up to and including 3DGW (except for 1P6D, 22RC-22RF and 23WK-3DGP)". The presence of serial-number exceptions requires careful serial-number verification. Treating model or part-number alone as sufficient could miss the listed serial-number exceptions or reach incorrectly into excluded units.

Saab 340 carve-out depends on SB 58 incorporation: The AD excludes certain ADC-85A units (part numbers 822-0370-113 or -123) that have Rockwell Collins SB 58 incorporated and are installed on Saab 340 series aeroplanes. The carve-out depends not only on part number and platform but also on a prior modification (SB 58) having been incorporated. Operators must be able to demonstrate that SB 58 is incorporated on a given unit to claim the Saab 340 exception. Absence of clear records of SB 58 incorporation could mean a unit is treated as affected even if it had previously been modified.

Manufacturer documentation is the operative standard: The AD requires compliance "in accordance with Rockwell Collins SB 62, (ADC-85/85A/850C/850D/850E/850F-34-62), Revision No. 2, dated 7 March 2000, or SB 62, dated 25 October 1999, as applicable, together with the applicable Collins Computer Component Maintenance Manual and Collins Avionics Standard Shop Practices Instruction Manual." The AD thereby makes the SB and manuals the standard of work. An incorrect SB revision or failure to use the Collins manuals could lead to non-conforming work. The AD provides two SB dates as alternatives "as applicable", so practitioners must determine which SB applies to the specific unit configuration.

Testing requirement and proof: Requirement 1.c requires testing of the ADC. The AD does not set out the test criteria in the text; instead it refers to SB 62 and the Collins manuals. Operators must therefore ensure that testing is carried out exactly as those documents require and that records of the tests are kept to evidence compliance. Failing to document the testing in a way that traces back to the SB and manuals could complicate regulatory review.

Installation prohibition timing: Requirement 2 is effective as of the amendment effective date. The Compliance section keeps Requirement 1’s timing as "Within 12 months after the effective date of the original issue of this Directive" but makes Requirement 2 effective immediately with the amendment. That means that, even if some operators had a longer window to perform the modification and testing under Requirement 1, they could not install affected ADCs after the amendment date unless the tests and modifications are complete. Careful scheduling is needed to avoid being caught with an uninstalled but non-compliant part when a short-notice installation is required.

Operational placard is recommended, not mandatory: Note 2 recommends an operational placard per Rockwell Collins Operator Bulletin 99-7 until the directive’s actions are performed. CASA states the placard is not necessary to address the unsafe condition but highly recommends it. Operators should note the difference between mandatory AD requirements and this recommended interim measure; relying solely on the placard without performing the required hardware reprogramming/replacement and testing will not satisfy the AD.

Cross-reference to FAA materials: Note 3 refers to FAA AD 2002-14-19 and FAA SAIB CE-03-21. These references may contain relevant technical detail or alternative attestations about affected models and mitigations. However, the AD makes Australian compliance contingent on CASA’s directive and Rockwell Collins SB 62, not on FAA documents. Treat FAA references as context rather than as substitute compliance paths within Australian jurisdiction.

Parts inventory and interchange effects: Because the AD forbids installation of affected ADCs on aeroplanes except Saab 340s unless modified and tested, operators that rely on spare ADCs in inventory must ensure spares have the required modifications and testing documented. Installing an inventory part without that documentation would run afoul of Requirement 2.

Finally, the AD’s background explains the unsafe condition tested in flight: an unwarranted ADC flag in response to Normal/Alternate Air static source selection capability. Operators should not assume all symptom profiles are covered by the AD’s corrective action; the AD prescribes specific modification and testing steps per SB 62, and other unusual failure modes or unrelated ADC anomalies will require separate assessment.

Compliance requires a sequence of identification, removal, corrective action, testing and installation controls aligned to the AD’s Requirements and the referenced manufacturer documentation.

1. Identify affected units. Cross‑check installed ADCs against the Applicability table in the AD, confirming unit model, part number and serial number. Pay special attention to the ADC-850D serial-number carve-outs and to the Saab 340 exemption for ADC-85A part numbers 822-0370-113 or -123 only where SB 58 has been incorporated and the unit is installed on a Saab 340 series aeroplane.

2. Plan removal and logistics. Requirement 1.a requires removal of any affected ADC from the aeroplane. Schedule removals to fit within maintenance windows and the compliance timing. The AD preserves Requirement 1’s compliance timing as "Within 12 months after the effective date of the original issue of this Directive", so verify the applicable calendar deadline relative to the original effective date (recorded as 5 September 2002 in the AD). For installations that require immediate action to avoid installation breaches, note Requirement 2’s immediate effect as of the amendment effective date (12 June 2003).

3. Perform corrective work to SB standard. Requirement 1.b requires replacement or reprogramming of parts or circuit card assemblies on the CPU cards "as applicable". Perform that work strictly in accordance with Rockwell Collins SB 62, either Revision No. 2 dated 7 March 2000 or the SB dated 25 October 1999 as applicable to the unit, together with the Collins Computer Component Maintenance Manual and Collins Avionics Standard Shop Practices Instruction Manual. Confirm which SB revision is applicable to the specific unit configuration before commencing work.

4. Test per SB and manuals. Requirement 1.c mandates testing of the ADC in accordance with SB 62 and the Collins manuals. Ensure that the testing procedures, pass/fail criteria and test records conform to the SB and manuals. Retain test records in a manner that evidences that the ADC was tested and passed in line with the specified documentation.

5. Do not reinstall until compliance demonstrated. Requirement 2 forbids installation of affected ADCs on any aeroplane, except Saab 340 series aeroplanes, unless the modification and testing required by Requirement 1.b and 1.c have been accomplished. Before installing a spare or returning a unit to service, verify and document that the required work and testing have been completed and that records tie to the SB and manuals.

6. Consider interim placard. Although Note 2 states the placard per Rockwell Collins Operator Bulletin 99-7 is not necessary to address the unsafe condition, CASA "highly recommends" installing it until the AD’s actions are accomplished. Operators may choose to adopt that recommendation as a temporary operational mitigation while awaiting shop work.

7. Maintain traceability. Because the AD references specific part numbers, serial numbers and SB revisions, keep documentation demonstrating unit identity, the SB revision used, the replacement/reprogramming actions performed, the shop that performed them, the test reports, and any conforming certification or release-to-service paperwork required under existing maintenance regulations. The AD itself ties the acceptable methods to specific Collins documents, so records must link to those documents.

8. Coordinate with OEM/service providers. The AD requires work "in accordance with" Rockwell Collins SB 62 and the Collins manuals. Engage with authorised Collins repair stations or organisations familiar with the SB and the component maintenance manual to ensure technical conformity and access to necessary software, parts and test equipment.

9. Monitor installation restrictions for Saab 340 exception. If a Saab 340 operator believes a unit is exempt because SB 58 has been incorporated on an ADC-85A part number 822-0370-113 or -123, verify and document the SB 58 incorporation date and evidence before treating the unit as exempt.

10. Record compliance steps and dates. The AD states the timing and effective dates for compliance: Requirement 1’s timing remains as per the original issue, and Requirement 2 is effective as of the amendment date. Document the dates of removal, repair/reprogramming, testing and reinstallation to demonstrate compliance within the AD’s stated windows.

Following these steps, performed in accordance with Rockwell Collins SB 62 and the Collins manuals, implements the AD’s technical requirements and addresses the unsafe condition described in the Background. Where maintenance, parts supply, or scheduling constraints exist, plan around the AD’s installation prohibition and consider application of the recommended placard per Operator Bulletin 99-7 as an interim measure pending completion of the remedial work.