AD/EMB-145/3 - Pitot and TAT Current Sensor Relays

The central concept is the detailed inspection (DET). The AD defines DET as “an intensive examination of a specific item, installation or assembly to detect damage, failure or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate access procedures may be required.” This is a high‑scrutiny inspection, not a simple visual check. The AD targets current sensor relays: electromechanical components that monitor current in the pitot heater and TAT heater circuits. Poor electrical contacts in these relays or their sockets cause overheating, leading to smoke. The AD distinguishes between damaged and undamaged units. Damage is not defined further but presumably includes evidence of overheating, arcing, melted plastic, discolouration, or contact pitting. A key concept is re‑identification: if a socket is undamaged it must be reworked by replacing two contacts (A1 and C1), and then the socket part number changes from S500‑9140 to S500‑9140‑A and the electrical code changes from XK0053, XK0054, XK0064, XK0494 to XK1243, XK1242, XK1245, XK1244 respectively. This re‑identification ensures that the reworked sockets are distinguishable from original ones and that the aircraft wiring diagrams reflect the modification. Another concept is time in service: compliance for Requirements 1 and 3 is tied to “2 500 hours time in service after 21 December 2007 or before 21 December 2009, whichever occurs first.” Time in service is total flight hours, not calendar days. The AD also introduces the notion of before further flight: if a relay or socket is found damaged, replacement must occur before the aircraft next flies. This imposes immediate grounding risk for any aircraft found non‑compliant during the inspection. The directive is foreign‑sourced: it originates from a Brazilian ANAC AD (2007‑11‑04R1) and is adopted by CASA under delegation. The AD incorporates Embraer service bulletins by reference: SB 145‑30‑0052 for ordinary EMB‑145 models and SB 145LEG‑30‑0019 for Legacy executive jets. Operators must obtain and follow those bulletins for the detailed procedures; the AD itself only summarises the scope. The AD uses “Note 1” to clarify that the 145LEG series of bulletins applies only to Legacy executive jets, preventing confusion for operators of standard EMB‑145 aircraft. Note 2 provides the DET definition. Note 3 references the underlying ANAC AD. The applicability is limited by serial number blocks, but note the final block “145592 through 14500987” which appears to be a typographical error (possibly meaning 145592 through 145987). Operators must interpret the serial number range accurately.

The AD directly affects owners, operators and maintenance organisations of Embraer EMB‑145 series aeroplanes with serial numbers between 145002 and 145987 inclusive, subject to the three specified ranges. Aircraft outside those S/Ns are not required to comply. The title mentions EMB‑135 but the applicability clause only lists EMB‑145 models; EMB‑135 operators are not caught by this specific AD, though they may be subject to other directives. The AD also affects CASA itself as the issuer and enforcer; the AD is signed by a delegate of CASA. It affects the Brazilian ANAC insofar as the underlying AD is referenced. It affects Embraer as the manufacturer: the service bulletins are Embraer publications, and the AD relies on them for compliance methods. The AD affects parts suppliers who produce the replacement relays (CS500‑060‑D4A), sockets (S500‑9140‑A, S500‑9216), and contacts (M39029/92‑536). The AD may also affect aircraft insurers who may require evidence of compliance. Lessors and financiers may include compliance with all applicable ADs as a contractual condition. Pilots and flight crews are indirectly affected because the AD aims to reduce smoke‑on‑flight‑deck risks, improving safety but also imposing maintenance scheduling constraints. Regulatory auditors (CASA airworthiness inspectors) may check compliance records. The compliance burden falls heavily on small operators with limited fleets; the inspection requires specialised labour and parts, and the “before further flight” requirement can cause unexpected grounding if damage is found. The AD does not distinguish between commercial air transport, charter, or private operation; the applicability is by serial number only, so all operators of affected aircraft must comply regardless of usage. The AD also affects maintenance, repair and overhaul (MRO) facilities that perform the inspections and replacements; they must be familiar with the service bulletins and have the specified parts and training. Record‑keeping staff must update aircraft maintenance logs with the inspection results, part replacements, and re‑identification changes. The AD may also affect future buyers of affected aircraft, who will need to verify compliance before purchase.

The primary duty is on the operator or owner of an affected aircraft to ensure that the inspections, replacements and reworks required by the AD are completed within the specified compliance times. The operator must schedule the aircraft for a detailed inspection of the four relays and four sockets within 2,500 hours time in service after 21 December 2007 or by 21 December 2009, whichever is earlier. This is a hard deadline; failure to comply renders the aircraft non‑airworthy. If during that inspection any relay is found damaged, the operator must replace it with a new relay of the same part number before the next flight. If any socket is found damaged, the operator must replace it with a new socket (P/N S500‑9140‑A or S500‑9216) before the next flight. If a socket is undamaged, the operator must perform a rework: replace electrical contacts A1 and C1 with new ones, then re‑identify the socket with the new part number and electrical codes as specified. The operator must use the procedures in either Embraer Service Bulletin 145‑30‑0052 (for standard EMB‑145) or SB 145LEG‑30‑0019 (for Legacy jets), or later ANAC‑approved revisions. The operator has the right to use later revisions of those bulletins if they are approved by ANAC; the initial issue is not mandatory. The operator also has the right to reinstall undamaged relays (if they pass inspection). The operator has the right to choose which compliant socket part number to fit if replacement is needed (either S500‑9140‑A or S500‑9216). The operator has no right to defer the inspection beyond the compliance window, and no right to fly an aircraft with damaged relays or sockets discovered during inspection unless the replacement is accomplished. The AD does not explicitly grant an alternative method of compliance (AMOC) process, but since it is a CASA AD, operators can likely apply for an AMOC under Civil Aviation Regulations 1988 Part 21; the source does not mention this. The operator’s duty to record the work is implied: maintenance records must document the inspection, findings, part replacements, re‑identifications, and the service bulletin reference used. The AD does not specify a particular record format but standard maintenance release practices apply. The operator also has a duty to ensure that maintenance personnel performing the work are appropriately qualified and authorised under CASA regulations. The operator may engage a contracted MRO; the duty cannot be delegated but compliance can be performed by another entity. If the aircraft is sold, the previous operator’s duty may survive in the form of warranty or sale contract terms, but the AD duty runs with the aircraft registration.

The source itself does not list penalties; however, as an airworthiness directive issued under the Civil Aviation Act 1988 (Cth), non‑compliance is a breach of the Act and regulations. The Act provides for civil penalties of up to hundreds of thousands of dollars for corporations and individuals, criminal sanctions for reckless conduct, and administrative action including suspension or cancellation of an Air Operator’s Certificate, maintenance organisation approval, or aircraft certificate of airworthiness. Specifically, operating an aircraft that does not comply with an applicable AD is a contravention of Civil Aviation Regulation 1998 42.130 (and equivalent in the 1988 Regulations) and can result in enforcement action by CASA. The police may also be involved if the breach amounts to a safety risk. The AD gives CASA the power to direct the operator to ground the aircraft if non‑compliance is detected. The AD itself does not specify a fine amount, but under the Civil Aviation Act 1988 section 32, the maximum penalty for a contravention of a direction can be 250 penalty units for an individual (currently $55,000) and 1,250 penalty units for a corporation (currently $275,000), plus daily penalties for continuing breaches. The regulator may also issue infringement notices (on‑the‑spot fines) for less serious non‑compliance, typically around 12 penalty units. The AD does not create a private right of action for damages; only CASA can enforce it. However, if non‑compliance leads to an accident, the operator may face civil liability under common law or the Civil Aviation (Carriers’ Liability) Act 1959. The AD’s “before further flight” requirement means that any aircraft that has not completed the required replacement or rework after a finding of damage is unairworthy; flying it is a serious breach that could constitute an offence under section 20B of the Civil Aviation Act (reckless operation). Enforcement history: The source does not recount any prior litigation or enforcement actions related to this specific AD, but CASA’s general enforcement approach includes surveillance, audits, and targeted inspections. Operators should expect that compliance records will be checked during regular airworthiness reviews. If damage is discovered during an inspection, the operator must ensure no further flight without corrective action; failure to do so could lead to immediate enforcement including seizure of the aircraft.

This AD operates under the hierarchy of Australian aviation law. It is a directive issued by CASA under delegation under the Civil Aviation Act 1988 (Cth). It supplements existing regulations: the Civil Aviation Regulations 1998 (CAR 1998) and Civil Aviation Safety Regulations 1998 (CASR 1998) require that all mandatory continuing airworthiness information, including ADs, must be complied with. The AD has the force of law and takes precedence over any conflicting manufacturer’s recommendations or maintenance manual instructions. For example, if Embraer’s own maintenance planning document suggests a different inspection interval for the relays, the AD overrides it. The AD references Brazilian ANAC AD 2007‑11‑04R1; this AD is adopted by CASA as the local equivalent. Operators in Australia must comply with the CASA AD even if they have already complied with the ANAC AD, although in practice the requirements are identical. The AD incorporates by reference Embraer Service Bulletins 145‑30‑0052 and 145LEG‑30‑0019 (initial issue or later ANAC‑approved revisions). Those bulletins become mandatory for the specific actions described in the AD; other parts of the bulletins (e.g., optional modifications) remain non‑mandatory unless otherwise covered by another AD. The AD interacts with the Part 145 maintenance regulations: the work must be performed by a maintenance organisation approved under CASR Part 145 or by a person with appropriate certification under CAR 42. The AD also interacts with the aircraft’s type certificate data sheet; any part number changes (e.g., socket re‑identification) must be recorded in the aircraft records and may affect future parts ordering. The AD does not override the requirement to report defects under CAR 42.10: if damage is found, it may also need to be reported as an unairworthy condition. The AD does not deal with environmental laws, workplace health and safety laws, or competition laws. However, the disposal of old relays and sockets may be subject to hazardous waste regulations if they contain hazardous materials (the AD does not mention this). The AD also interacts with contractual laws: operators may have lease agreements that require compliance with all ADs. Failure to comply could constitute a breach of contract, giving the lessor rights to terminate or demand rectification. The AD does not interact with privacy laws, intellectual property laws, or criminal laws beyond aviation safety.

The source records that this AD was issued on 16 June 2008 and became effective on 23 June 2008. It does not include any earlier amendments to AD/EMB‑145/3 itself. However, it references ANAC AD 2007‑11‑04R1, which is an earlier directive from the Brazilian ANAC. The “R1” suffix indicates that the ANAC AD had been revised at least once before. The CASA AD does not state whether it supersedes any previous CASA AD on the same subject. The AD is identified as “8/2008 DM” in the top right corner; that may be an internal CASA reference number. The AD is not a re‑issue or amendment of any earlier CASA AD; it is a new directive. Operators should check whether any subsequent CASA ADs have amended or superseded AD/EMB‑145/3. The source text does not provide that information. The AD also does not list any prior applicable ADs on the same configuration, though it notes “ANAC AD 2007‑11‑04R1 refers” in Note 3. That may mean that the ANAC AD is the originating requirement, and the CASA AD adopts it with minor modifications. The service bulletins referenced (SB 145‑30‑0052 and SB 145LEG‑30‑0019) are initial issue; later revisions approved by ANAC are permitted. The AD itself does not specify which revision of those bulletins is current as of June 2008. Operators must use the latest ANAC‑approved revision at the time of compliance, but the AD explicitly allows “later revisions approved by the ANAC”. That gives flexibility. The AD includes no sunset date; it remains in effect until superseded or withdrawn. The source does not indicate any amendment process within the AD itself. Any future changes to the AD would presumably be made by issuing a new CASA AD that supersedes this one. The signature by James Coyne as Delegate of CASA indicates that the AD was legally made under the relevant delegation.

The source does not mention any litigation history associated with this specific AD. No court cases, tribunal decisions, or administrative appeals are cited. Given that it is a technical airworthiness directive, litigation is uncommon unless a party disputes the factual basis for the AD, the compliance deadline, or the extent of CASA’s authority to issue it. The Australian Administrative Appeals Tribunal may hear reviews of CASA decisions to issue ADs if an applicant can show standing, but such cases are rare. The Federal Court may also hear judicial review applications under the Administrative Decisions (Judicial Review) Act 1977. However, the source provides no information on any such proceedings. In practice, airworthiness directives are typically complied with without litigation because non‑compliance directly affects airworthiness and exposes the operator to grounding and financial penalty. It is possible that the underlying ANAC AD (2007‑11‑04R1) was subject to challenge in Brazil, but the source does not address that. The absence of cited litigation does not mean none has occurred; it simply means the source did not include any such history. Users of this deep dive should not assume the AD has never been challenged. The AD’s technical foundation (reports of smoke on flight deck) appears uncontroversial. No party is identified as having sought an alternative method of compliance or a waiver. The directive is straightforward and prescriptive, leaving little room for legal dispute. If a dispute were to arise, it would likely centre on whether the inspection was thorough enough or whether a particular socket was truly undamaged. The AD’s reliance on service bulletins for the method of compliance may also give rise to arguments about whether a particular deviation is permissible. Without any source‑grounded litigation history, the best statement is that the source records none.

The AD contains several potential traps for the unwary. First, the compliance deadline is not simply a single date. Requirement 1 (inspection of relays) and Requirement 3 (inspection of sockets) must be completed by the earlier of after 2,500 hours time in service since 21 December 2007 or by 21 December 2009. This means an aircraft that accumulates hours slowly must still comply by the calendar deadline. Conversely, an aircraft that flies a lot may reach the hour limit before the calendar date; operators must track hour accumulation carefully from 21 December 2007. The AD effective date (23 June 2008) is not the starting point for counting hours; the starting point is 21 December 2007 (the effective date of the ANAC AD). Any hours flown after that date count. Second, the “before further flight” requirement for replacements (Requirements 2 and 4) applies immediately upon finding damage during the inspection. This can cause an aircraft to be grounded unexpectedly if spare parts are not on hand. Operators should pre‑order relays and sockets to avoid downtime. Third, the re‑identification of undamaged sockets is mandatory even if the sockets appear serviceable. Simply reinstalling them after inspection without replacing contacts and re‑identifying would not comply. The new electrical codes (e.g., XK1243 instead of XK0053) must be changed on the aircraft wiring diagrams, labelling, and in the maintenance records. Failure to update the codes could confuse future maintenance. Fourth, the AD only applies to EMB‑145 models in the listed serial number ranges. EMB‑135s are not covered despite the title. Operators of EMB‑135s should not rely on this AD; they must check if a separate AD applies. Fifth, the service bulletins are incorporated by reference; operators must obtain the correct bulletin for their aircraft variant. Using the wrong bulletin (e.g., using SB 145‑30‑0052 on a Legacy jet) may lead to incorrect procedures. Sixth, the AD does not specify a grace period for discovering non‑compliance. If an operator has not performed the inspection by the deadline, the aircraft is immediately non‑airworthy, regardless of whether the operator was unaware of the AD. Seventh, the AD allows later revisions of the service bulletins approved by ANAC, but not revisions approved only by Embraer. Operators must verify that any revision they use has explicit ANAC approval. Eighth, the definition of “detailed inspection” requires “surface cleaning and elaborate access procedures may be required.” Operators must budget for access labour; the inspection is not a quick visual check. Ninth, the part number for replacement relays is CS500‑060‑D4A; using a different part number even if electrically equivalent is not permitted unless an AMOC is granted. Tenth, the AD does not explicitly state that the inspections are one‑time only or recurring; reading the compliance paragraph says “If not previously accomplished” for both Requirements 1 and 3, suggesting that after initial compliance, no further action is required unless future ADs mandate repeat inspections. However, the AD does not contain a repeat interval; it appears to be a one‑time modification campaign. Operators must still monitor for any subsequent ADs.

To comply with AD/EMB‑145/3, an operator of an affected EMB‑145 aircraft should follow these steps. Step 1: Determine applicability. Look up the aircraft serial number and confirm it falls within the listed ranges: 145002 through 145362, 145364 through 145590, and 145592 through 14500987 (interpreted as up to 145987). Step 2: Obtain the correct Embraer Service Bulletin. For standard EMB‑145, use SB 145‑30‑0052 initial issue or later ANAC‑approved revision. For Legacy executive jets, use SB 145LEG‑30‑0019. Step 3: Schedule the detailed inspection. The inspection must be completed by the earlier of 2,500 hours time in service after 21 December 2007 or 21 December 2009. Calculate the aircraft’s hours flown since 21 December 2007 and the hours remaining. Ensure the inspection is done before that limit. Step 4: Perform the detailed inspection. As defined, this is an intensive examination of relays K0053, K0054, K0064, K0494 and sockets XK0053, XK0054, XK0064, XK0494. Use good lighting and possible access aids. Look for evidence of overheating, damage, failure, or irregularity. Follow the service bulletin procedures. Step 5: Decide based on findings. For relays: if undamaged, reinstall. If damaged, replace with new relay P/N CS500‑060‑D4A before further flight. For sockets: if undamaged, rework by replacing electrical contacts A1 and C1 with new ones (P/N M39029/92‑536). After rework, re‑identify the socket part number to S500‑9140‑A and change electrical codes from XK0053 to XK1243, XK0054 to XK1242, XK0064 to XK1245, and XK0494 to XK1244. If socket is damaged, replace with new socket P/N S500‑9140‑A or S500‑9216 before further flight. Step 6: Document all work. Record in the aircraft maintenance log the date, hours at inspection, service bulletin reference, part numbers installed, re‑identification changes, and any findings. If damage was found, note the corrective action. Step 7: Update aircraft records. Ensure wiring diagrams, maintenance manuals, and parts lists reflect the new electrical codes and part numbers for reworked sockets. Step 8: Retain evidence of compliance. Keep copies of the service bulletins used, work orders, and logbook entries. This may be requested during a CASA audit or airworthiness review. Step 9: Monitor for future ADs. Although this AD appears to be a one‑time requirement, operators should check for any superseding ADs or repeated inspection requirements. Step 10: Consider economic impact. Budget for labour (several hours per aircraft), parts (relays ~$100‑$200 each, sockets ~$500‑$1,000, contacts ~$20), and potential aircraft downtime if grounding is required during parts procurement. Pre‑ordering parts reduces downtime risk.