AD/ERJ-190/20 - Outboard Slat Skew Sensor

The Directive rests on a small set of clearly stated concepts that determine scope, action, timing and technical reference.

Applicability concept

• The AD applies only to the listed ERJ-190 variants that are equipped with outboard slat skew sensors with P/N 1702286A or P/N 1702288A. Applicability is therefore conditional on both airframe model and installed equipment identification. If an airframe does not carry those part numbers, the AD’s requirements do not apply as written.

Operational check (OPC) concept

• The AD mandates an OPC as defined in the Directive: "A task to determine if an item is fulfilling its intended purpose. Since it is a failure finding task, it does not require quantitative tolerances." That definition limits the OPC to a pass/fail functional verification rather than a measurement to a tolerance band. The prescribed OPC must be performed "in accordance with Aircraft Maintenance Manual (AMM) Task 27-83-01-710-801-A".

Serviceable definition

• The AD defines "serviceable sensor" as one that has passed the Requirement 1 OPC. This ties the replacement eligibility for spare parts directly to the same OPC procedure, rather than to a broader overhaul, bench test or traceable life-limited metric.

Failure response concept

• If the OPC identifies a failure, the AD requires replacement with a serviceable sensor before further flight. There is no authorisation in the AD for operations with a failed sensor pending repair; the replacement must occur prior to the aircraft’s next flight.

Recurring interval concept

• The AD sets a compliance interval of 1,320 hours TIS initially (if not already done) and as the repeat interval. The interval is expressed in hours time in service, which structures maintenance planning around flight hours rather than calendar days or cycles.

Reference to technical source and foreign authority

• The AD gives a specific AMM task as the procedural reference and also notes "ANAC AD 2009-02-03 refers." The background explicitly credits ANAC reporting of occurrences and identifies the hazard sequence. The AD therefore blends domestic regulatory requirement with a foreign authority’s findings and a manufacturer/airframe technical manual procedure.

Safety rationale concept

• The background states the safety rationale: sensor failures have been found, and in combination with actuator structural failure and torque limiter failure, may result in slat detachment capable of damaging the horizontal stabilizer/elevator and affecting controllability. The Directive frames the OPC as corrective action intended to mitigate that chain of events.

Temporal and administrative facts

• The AD sets its effective date as 7 May 2009 and includes the date and delegate signature (26 March 2009). Those dates anchor compliance timing and administrative provenance.

These concepts determine the operational and maintenance consequences: identification of affected aircraft by part number, use of a pass/fail functional test from the AMM, replacement of any failed sensor before further flight, and repeat inspections at 1,320-hour TIS intervals. The AD does not specify repair procedures beyond replacement with a sensor that passes the OPC, nor does it include alternative methods of compliance, nor explicit recordkeeping or penalty clauses in the text supplied.

The Directive identifies a narrow class of affected parties and responsibilities.

Operators and aircraft owners

• The primary economic actors who must act are operators and owners of the listed ERJ-190 models that are fitted with the specified slat skew sensor part numbers. Because the AD’s applicability is explicitly conditional on the installed P/N, an operator that does not have P/N 1702286A or 1702288A installed is not subject to the Directive’s operational requirements. For those who do have those P/Ns installed, the Directive requires scheduling and performance of the OPC within the stated TIS interval and recurring thereafter.

Maintenance organisations and maintenance personnel

• The AD requires performance of a specific AMM task (27-83-01-710-801-A). That task will typically be performed by maintenance personnel authorised to work on Embraer ERJ-190 systems and who have access to the AMM. Maintenance organisations responsible for line or base maintenance must integrate the OP C into maintenance programmes and staffing, and must ensure that the personnel performing the AMM task understand that the OPC is a failure-finding, pass/fail check as stated.

Parts suppliers and inventory managers

• Because the Directive requires replacement "with a serviceable one" if a failure is found, parts management must account for serviceable spares. The AD defines serviceable as one that has passed the OPC, so spare parts policy must ensure that available sensors have been functionally checked, or that new sensors are managed so they pass the OPC prior to installation. Suppliers and supply-chain managers for those P/Ns may see demand for new units or for pre-tested spares.

Flight operations planners

• The compliance interval and the "before further flight" replacement requirement create constraints for dispatch and trip planning. Flight operations or dispatch teams must ensure aircraft are not scheduled for departure when an outboard slat skew sensor has failed an OPC; replacement must occur first.

Regulatory staff and authorised delegates

• The AD is issued under the Civil Aviation Safety Authority and signed by a delegate, James Coyne. Regulatory decision-makers and delegates within the authority are the issuing parties, and the AD itself stands as the instrument requiring compliance by the named operators. The AD also references ANAC AD 2009-02-03, which affects interactions with the Brazilian regulator and any bilateral coordination on continued airworthiness actions.

Manufacturers and type certificate holders

• Embraer as the manufacturer and the holder of the maintenance documentation is implicated because the AMM task specified is the procedural means of performing the OPC. The AD leverages the manufacturer's AMM rather than prescribing ad hoc procedures, so Embraer’s AMM content and clarity materially affect compliance costs and risk of misinterpretation.

Who is not affected

• Aircraft of the listed ERJ-190 models that do not carry the two specified slat skew sensor part numbers are not targeted by this Directive as rendered. The AD also does not apply to other aircraft types or to slat skew sensors with other part numbers, on the face of the text supplied.

In sum, affected parties are operators and maintenance organisations responsible for ERJ-190 aeroplanes with P/N 1702286A or 1702288A sensors; they must perform the AMM-prescribed OPC at the 1,320-hours TIS interval and replace any failed sensors prior to further flight. The Directive’s applicability by part number concentrates obligation on a subset of ERJ-190 fleet carrying those specific components.

The Directive imposes a small set of precise duties on operators and maintenance personnel; it does not state procedural rights, waivers or alternative methods of compliance within the text provided.

Duties

1. Perform the Operational Check (Requirement 1)

• Duty: Conduct an OPC of the outboard slat skew sensor P/N 1702286A or P/N 1702288A in accordance with Aircraft Maintenance Manual Task 27-83-01-710-801-A.
• Timing: Initially, if not previously done, within the next 1,320 hours time in service after the Directive’s effective date (7 May 2009); thereafter repeat at intervals not exceeding 1,320 hours TIS.
• Nature of the task: The AD’s Note 1 clarifies that the OPC is a failure-finding task that "does not require quantitative tolerances", meaning the maintenance action should determine whether the sensor performs its intended function rather than measure it against numeric tolerances.

2. Replace failed sensors (Requirement 2)

• Duty: If the Requirement 1 OPC identifies a sensor failure, replace the failed sensor with a "serviceable one" before further flight after the OPC.
• Serviceable definition: Note 2 defines a serviceable sensor as one that has passed the Requirement 1 OPC. Therefore, the replacement part must itself be functionally verified under the same AMM OPC procedure before it can be considered serviceable for installation.

3. Follow AMM procedure

• Duty: The OPC must be performed "in accordance with" the specific AMM Task referenced. This ties performance standards to the manufacturer's approved maintenance documentation.

4. Observe effective date

• Duty: The AD is effective 7 May 2009; compliance timing is determined relative to that effective date.

Rights and procedural gaps in the text

• No explicit rights for alternative methods of compliance (AMOC) or deviation are stated in the text provided. The Directive does not, in this excerpt, offer an avenue for operators to seek an alternate or equivalent procedure or an extension of the compliance interval; nor does it provide an express procedure for applying for such relief.
• No explicit rights to credit previous actions are articulated beyond the initial clause "If not previously accomplished" for Requirement 1, which implies that past performance of the OPC counts toward initial compliance if already done, but the AD does not prescribe how to demonstrate that prior compliance.
• The AD does not articulate recordkeeping requirements, so the Directive text as supplied does not state the documentation that operators must retain to demonstrate compliance. Practically, operators would be expected to follow normal maintenance recordkeeping standards, but the AD itself does not set that out in the provided text.

Delegation and issuing authority

• The AD is issued by the Civil Aviation Safety Authority and signed by a delegate, James Coyne. That signature identifies the issuing authority and the administrative provenance for the Directive.

Interplay between duties

• The AD links the definition of a "serviceable sensor" directly to the OPC, creating a circular but clear compliance requirement: only a sensor that has passed the OPC may be fitted to replace a failed sensor. The absence of provision for bench testing or other acceptance criteria in the AD means operators must apply the AMM OPC to spare sensors or otherwise ensure that spares are functionally verified.

In summary, the AD imposes discrete duties: perform the AMM-specified OPC at 1,320-hour intervals; replace failed sensors with sensors that have passed that OPC; and ensure initial compliance within 1,320 hours TIS after the effective date if the check has not already been done. The AD text contains no explicit procedural rights for alternative compliance or recordkeeping within the supplied excerpt.

The text supplied for this Airworthiness Directive does not set out explicit penalty provisions or enforcement mechanisms within its wording. The Directive states the actions required and the effective date, but it contains no fines, sanctions, or administrative penalty clauses in the material provided.

What the Directive does provide that bears on enforcement practicalities

• Issuing authority and signature: The document is signed by James Coyne, identified as "Delegate of the Civil Aviation Safety Authority", dated 26 March 2009. That signature gives administrative provenance and indicates that the AD is an enforceable safety directive issued by the civil aviation regulator.
• Effective date and compliance timing: The AD declares an effective date of 7 May 2009 and prescribes mandatory compliance intervals (initial within 1,320 hours TIS, then recurring at intervals not to exceed 1,320 hours TIS). These temporal obligations are the determinative compliance metrics inspectors and auditors would use to assess whether an operator has met the Directive's requirements.

What is absent in the text provided

• No stated civil penalty, fine schedule, or criminal penalty language appears in the AD as given.
• No explicit inspection or audit regime is described in the AD text.
• No specific enforcement remedies (grounding, operational prohibition, certificate actions) are provided in the supplied text.

Operational significance of these absences

• Because the AD is an instrument of an aviation regulator, compliance assessment, enforcement, and potential sanctions would normally be managed under the regulator’s general enforcement, oversight and operator certification frameworks. The Directive itself, however, does not enumerate those mechanisms or penalties in the text supplied. Consequently, the AD gives clear technical and timing obligations but leaves detail on enforcement procedures and sanctions to the wider regulatory framework or to other communications from the authority not contained in the AD excerpt.

Implications for operators

• Operators must treat the AD’s prescriptive requirements (the OPC interval, AMM task reference, and replacement-before-flight rule) as mandatory obligations from the regulator, documented by the AD’s effective date and signature; operational and compliance risk arises if those obligations are not met. While the AD does not specify penalties, non-compliance would typically be addressed by the regulator through its supervisory and enforcement processes, which are not described in the AD excerpt.

In sum, the AD details the required technical actions and timing but does not, within this text, specify penalties or enforcement mechanisms; the practical enforcement context is therefore determined by the regulator’s broader enforcement powers and procedures, which are not set out in the material supplied.

The Directive explicitly references and interacts with two external sources of authority and procedure within the AD text: the Aircraft Maintenance Manual (AMM) task and a foreign airworthiness directive. There are no other statutes or legal instruments referenced in the text supplied.

Interaction with Aircraft Maintenance Manual (AMM)

• The AD requires the operator to perform the OPC "in accordance with Aircraft Maintenance Manual (AMM) Task 27-83-01-710-801-A 'Outboard Slat Skew Sensor - Operational Test'." This creates an operational interaction whereby the regulatory requirement is implemented via a manufacturer's maintenance procedure. The AMM is the technical source for how the OPC is executed; therefore, the AD depends on the AMM's procedural content for compliance. Procedurally, this means the AMM task becomes the functional method to satisfy the AD, and discrepancies between the AD and the AMM would likely need to be resolved by reference to the AD intent and the AMM details.

Reference to ANAC AD 2009-02-03

• The AD states "Note 3: ANAC AD 2009-02-03 refers." The background also explains that the Brazilian Agência Nacional de Aviação Civil (ANAC) advised occurrences of outboard slat skew sensor failure. The AD thereby incorporates or recognises a foreign regulator’s findings as the basis for the domestic directive. The explicit reference points to an operational interaction: the domestic regulator (the Civil Aviation Safety Authority) has used ANAC’s findings to justify the AD and directs operators to be aware of that foreign AD. This may have implications for operators whose type certificates, maintenance programmes or supply chains are connected internationally.

Functional interactions implied (but not specified in text)

• The AD’s requirement to perform the AMM OPC and to replace failed parts before further flight implies operational interactions with an operator’s maintenance programme, fleet scheduling, and parts management processes. Those interactions are technical and administrative rather than statutory, but they affect compliance with the AD.
• The AD does not, in the supplied text, specify how compliance with the AD will be recorded, nor does it prescribe interaction with continuing airworthiness records or with any specific maintenance approval processes. It therefore relies on existing maintenance and regulatory practices for those details.

What is not in the AD text

• No other domestic statutes, regulations, or compliance instruments are cited in the supplied text. The AD does not reference an alternate methods of compliance procedure, waiver processes, or the regulator’s enforcement statutes. It also does not state whether other domestic directives, notifications, or service bulletins supersede or complement this AD.

Practical consequence for operators

• Operators must align their maintenance practices with the AMM task to meet the AD’s requirements and must be aware of and review the referenced ANAC AD for further context or instructions. Any procedural or legal questions about alternatives to the AMM procedure, extensions to compliance intervals, or deviation would have to be resolved through the regulator’s normal channels, because the AD text itself does not provide those mechanisms.

In short, the AD interacts directly with the manufacturer’s AMM task as the implementation vehicle and acknowledges a related Brazilian ANAC AD as the originating safety advisory. It does not, in this text, reference other domestic legal instruments or provide process-level cross-references for deviations or enforcement.

The AD excerpt supplies a concise record of adoption and origins, but it contains no subsequent amendments or revision history in the text provided. The documentary facts present are as follows.

Issuance and effective date

• The AD is signed by James Coyne, Delegate of the Civil Aviation Safety Authority, with the signature date recorded as 26 March 2009. The AD itself states that it "becomes effective on 7 May 2009." Those two dates provide the administrative issuance timestamp and the operational effective date that frame compliance timing for operators.

Reference to foreign AD as antecedent

• The AD explicitly notes "ANAC AD 2009-02-03 refers" and the background states that ANAC advised occurrences of slat skew sensor failure. This indicates the AD’s immediate antecedent is a Brazilian ANAC AD issued earlier in 2009; the Domestic authority used that foreign AD and its safety data as the basis for mandating the OPC in Australia.

No amendments or revisions shown

• The provided text contains no subsequent AD number changes, no corrigenda, no superseding directives, and no later revision dates. It does not bear any annotations indicating amendment, revocation, extension, or refinement within the excerpt supplied.

No internal versioning within the AD excerpt

• The AD does not show versions of the AMM task or alternative procedures. It references a single AMM Task (27-83-01-710-801-A) and does not indicate any later revisions to that task within the supplied text.

Implications for research and compliance

• For an operator seeking full historical compliance context, the supplied AD gives only the original issuance signature date and the effective date, plus the reference to ANAC AD 2009-02-03. The absence of amendment records in the text suggests either that there were no subsequent amendments to this AD or that any amendments are not included in the material provided here. To confirm whether later amendments were issued, an operator would need to consult the regulator’s official AD database or subsequent communications, which are outside of the AD text excerpt.

Concluding note on amendment history as presented

• Based solely on the supplied document, the amendment history is limited to issuance by the Civil Aviation Safety Authority (delegate signature, 26 March 2009) and the effective date (7 May 2009), with a cross-reference to ANAC AD 2009-02-03 as the origin of the safety reporting that prompted this Directive. No further amendment details appear in the provided material.

The supplied Directive text contains no litigation history, case citations or references to legal proceedings. It does not identify any judicial reviews, appeals, or legal challenges pertaining to the AD. The document is a standards-style regulatory instrument that sets out required maintenance actions and their timing; the text provided does not report any dispute, administrative appeal, or court decision relating to this AD.

What the text does show

• The AD includes the safety background, technical requirements, AMM reference, affected part numbers, applicability by model, compliance intervals, and the issuing delegate’s signature and dates. It does not contain any language about contested matters or references to litigation.

Implications for users consulting this AD

• Because there is no litigation history included, users should treat the AD as an uncontested regulatory requirement at the time of issuance as reflected in the supplied document. If operators or other parties need to know whether the AD has been subject to legal challenge or whether enforcement actions have resulted in precedent, they would need to search external records or regulatory enforcement logs. Such searches are beyond the content of the AD text provided.

Limitations based on supplied material

• The absence of litigation history in this AD does not mean none exists; it solely means the AD excerpt provides no information on litigation. Any further inquiry into disputes, legal interpretations, or judicial treatment of the AD would require sources outside the text supplied.

The Directive’s short text contains several operational and interpretative pitfalls that operators and maintenance organisations should be alert to. These are concrete matters grounded in the AD wording.

Applicability by part number

• Gotcha: The AD applies only to aeroplanes "equipped with the outboard slat skew sensor part number (P/N) 1702286A or P/N 1702288A." Operators must verify installed equipment P/Ns precisely. Misidentifying the installed sensor P/N could lead to incorrectly assuming the AD does or does not apply. Inspectors and maintainers must check the actual part numbers on the installed sensors or parts records rather than relying on aircraft model alone.

OPC definition limits the test

• Gotcha: The AD’s Note 1 defines the OPC as a failure-finding task that "does not require quantitative tolerances." That means the AMM OPC is a pass/fail functional check, not a detailed calibrated measurement to a tolerance band. If maintenance personnel mistakenly treat the OPC as a precision measurement task, they may expend unnecessary resources or misclassify outcomes. Conversely, interpreting "no quantitative tolerances" too loosely could permit insufficient testing. Operators must follow the AMM Task content to apply the pass/fail criteria intended by the AMM.

Serviceable definition and spare parts management

• Gotcha: Note 2 defines a "serviceable sensor" as one that has passed the Requirement 1 OPC. That creates an operational loop: spares must be functionally checked (via the AMM OPC) before being considered serviceable for installation. Organisations that assume a new, out-of-box sensor is automatically serviceable could be non-compliant unless the sensor actually passes the OPC. Inventory procedures must therefore account for pre-testing spares, or the installation process must include an OPC on the spare prior to fitting.

Replacement-before-flight requirement

• Gotcha: Requirement 2 requires replacement "before further flight after the Requirement 1 OPC is accomplished" when a failure is found. This leaves no allowance for deferred rectification or ferry flights to a maintenance base under operational waivers in the AD text provided. Operators must have replacement parts or contingency plans; otherwise a failed OPC will ground that aircraft for further flight until rectified.

Reliance on AMM task

• Gotcha: The AD mandates performing the OPC "in accordance with" a specific AMM Task (27-83-01-710-801-A). If operators rely on alternative procedures, test benches, or different documentation, those approaches are not authorised within the AD as supplied. Any alternative would require engagement with the regulator outside the AD text.

Timing and record of prior compliance

• Gotcha: The AD states initial compliance "if not previously accomplished, within the next 1,320 hours TIS after the effective date." It implies credit for earlier performance but does not explain how to document or demonstrate prior compliance. Operators who performed ad hoc checks prior to the effective date must have clear records available to demonstrate that the AMM OPC was performed to the required standard.

Potential misinterpretation of "before further flight"

• Gotcha: The phrase "before further flight after the Requirement 1 OPC is accomplished" could raise operational questions about flights performed after a successful OPC when no failure was found. The AD requires only replacement if a failure is found; where no failure is found, the aircraft is permitted to continue until the next scheduled OPC interval. Ensure clarity in operational control: a failure necessitates immediate replacement; a pass permits continued operation subject to interval constraints.

ANAC AD reference

• Gotcha: Note 3 says "ANAC AD 2009-02-03 refers." Operators should obtain and read the referenced ANAC AD for supplementary technical detail or context, because the domestic AD relies on ANAC’s reporting as the safety justification. Failure to consult the referenced AD may omit important contextual information.

No stated alternative methods of compliance or penalty clauses

• Gotcha: The supplied AD does not describe an AMOC process or specify enforcement penalties. If an operator needs relief or a different inspection methodology, the AD text does not outline the process or criteria for seeking it. Operators should engage with the regulator to clarify alternatives or relief mechanisms.

In summary, the principal operational gotchas are precise P/N applicability, the OPC’s pass/fail nature, the serviceable definition tying spares to the same OPC, the replacement-before-flight constraint, and the AD’s reliance on the AMM and ANAC AD for procedural and contextual detail. These points require careful procedural alignment in maintenance planning, parts management and dispatch decision-making.

The AD provides a concise, prescriptive compliance pathway. The following steps distil the Directive’s requirements into an operational checklist while staying strictly within the AD’s text and its referenced AMM task.

1. Determine applicability

• Verify whether each ERJ-190 in the fleet is installed with an outboard slat skew sensor P/N 1702286A or P/N 1702288A. The AD applies only to aeroplanes equipped with those part numbers and to the listed ERJ-190 models (ERJ 190-100 ECJ, ERJ 190-100 IGW, ERJ 190-100 LR, ERJ 190-100 STD, ERJ 190-200 IGW, ERJ 190-200 LR and ERJ 190-200 STD). Operators must confirm installed P/Ns through parts plates, maintenance records or physical inspection.

2. Schedule initial OPC within the specified initial window

• If the Requirement 1 OPC has not already been accomplished, schedule and perform it within the next 1,320 hours TIS after the AD’s effective date (7 May 2009). For aircraft that already performed a functionally equivalent AMM task prior to the AD, maintain documentary evidence showing that the AMM Task 27-83-01-710-801-A was performed to accept credit as "previously accomplished", since the AD allows initial compliance to be satisfied if already completed.

3. Perform the OPC using the AMM task

• Conduct the operational check exactly "in accordance with Aircraft Maintenance Manual (AMM) Task 27-83-01-710-801-A 'Outboard Slat Skew Sensor - Operational Test'." Because the AD defines the OPC as a failure-finding task that does not require quantitative tolerances, follow the AMM's pass/fail criteria rather than seeking measurement tolerances absent from the task instructions.

4. If the OPC finds a failure, replace before further flight

• If the Requirement 1 OPC identifies an outboard slat skew sensor failure, do not operate the aeroplane for further flight until the failed sensor is replaced with a "serviceable one." Note 2 specifies that a serviceable sensor is one that has passed the Requirement 1 OPC. Thus, ensure any replacement sensor has been functionally verified under the AMM OPC prior to installation.

5. Integrate the 1,320-hour recurring interval into maintenance planning

• Schedule subsequent OPCs at intervals that do not exceed 1,320 hours TIS. Update line/base maintenance schedules and maintenance control logs to ensure that inspections do not lapse beyond that interval.

6. Manage spares in accordance with the AD’s serviceable definition

• Treat spare sensors as serviceable only after they have passed the OPC. Ensure that stock management and parts procurement account for the need to verify spares using the AMM OPC before declaring them serviceable and using them as replacements.

7. Consult ANAC AD 2009-02-03 for context (as referenced)

• The Directive expressly notes that "ANAC AD 2009-02-03 refers" and the background references ANAC reporting. Operators should obtain and review ANAC AD 2009-02-03 to ensure they are aware of any additional technical details or observations that informed the domestic AD, noting that the domestic AD relies on those occurrences for its safety justification.

8. Document proof of compliance

• While the AD text does not specify recordkeeping requirements, good practice is to log each OPC, its outcome, the identification of the sensor (P/N and serial number), and any replacement action taken, with dates and signatures of maintenance personnel. Given the AD’s requirement that failed sensors be replaced before further flight, maintain documentation demonstrating that any replacements were done after a failed OPC and that replacement sensors passed the OPC before installation (as per the AD’s serviceable definition).

9. Clarify alternative procedures with the regulator if needed

• The AD text does not provide an alternative methods of compliance procedure. If an operator believes another inspection method or interval is appropriate, or if operational constraints necessitate an alternative approach, seek formal guidance or authorisation from the regulator, because the AD itself does not prescribe an alternate compliance mechanism within the supplied text.

10. Ensure operational control and dispatch alignment

• Ensure that flight operations and dispatch are aware of the before-flight replacement requirement. Dispatch must not authorise flights for aircraft with a failed OPC unless replacement has been completed and the replacement sensor has passed the OPC, per the AD.

By following these steps and strictly using the AMM Task 27-83-01-710-801-A for the OPC, and by respecting the 1,320-hour intervals and the "replace before further flight" rule for failures, operators will meet the AD’s expressed requirements. The AD’s effective date (7 May 2009) establishes the baseline for timing; operators must account for whether initial OPCs were performed prior to that date to claim credit.