AD/A109/63 - Battery Bus Circuit Breaker

The AD contains a small number of discrete, concrete concepts which govern its scope and execution. Applicability: the AD applies to Agusta A109E helicopters within a defined serial-number band and, for earlier serial numbers, only if equipped with certain kit part numbers. Specifically the AD applies to: all serial numbers up to and including S/N 11077 if equipped with kit part number P/N 109-0812-04-101, -103, -107 or -109; and serial numbers 11078 to 11758 inclusive, with three serial numbers explicitly excluded (S/N 11741, 11754 and 11757). This creates a two-tier applicability rule keyed to serial number and equipment fitment.

Requirement: the principal substantive obligation is to modify two electrical assemblies (P/N 109-0741-49 and P/N 109-0741-55) by installing the specified modification kit (P/N 109-0824-73-101). The modification details are not reproduced in full in the AD; instead, compliance is to be achieved by following the Agusta Bollettino Tecnico 109EP-98 dated 22 June 2009 or a later revision approved by EASA. The AD therefore incorporates by reference the Bollettino’s instructions as the method of compliance and permits later EASA-approved revisions to be used.

Technical change: the AD states the technical measure , replacement of a 35 Amp BATT BUS circuit breaker with a 50 Amp breaker and replacement of wires with oversized ones , as the engineered response to an identified root cause. The AD also records that Agusta developed a specific modification kit to implement this change.

Timing and enforceability: the AD imposes a concrete compliance window , within 50 hours time in service after the effective date of the AD but no later than 31 December 2009. The AD becomes effective on a specified date (7 July 2009). It also references EASA AD 2009-0137, indicating parallel or related regulatory action at EASA.

Authority and signatory: the AD document is signed and dated by James Coyne, Delegate of the Civil Aviation Safety Authority, establishing CASA as the issuing authority for the AD and identifying the date of signature (30 June 2009). The AD is titled AD/A109/63 and labelled “Battery Bus Circuit Breaker,” with the operational code “9/2009 DM.” These identifiers are part of the instrument’s administrative provenance.

In sum, the AD’s main concepts are a narrowly defined applicability, an express mandatory modification, a specified modification kit and Bollettino reference as the method of compliance, a short compliance window tied to hours-in-service or an absolute calendar date, and cross-reference to an EASA AD and EASA approval for later Bollettino revisions.

The AD applies only to Agusta A109E helicopters meeting the express applicability criteria set out in the instrument. That cohort is defined in two parts: first, all serial numbers up to and including serial number 11077, but only if those airframes are equipped with kit part number 109-0812-04-101, -103, -107 or -109; and second, serial numbers 11078 through 11758 inclusive, except for the explicitly excluded serial numbers 11741, 11754 and 11757. The AD therefore excludes A109E airframes outside those serial numbers and airframes within the first serial-number range that do not have the listed kit part numbers fitted. The AD’s text does not expand applicability to other Agusta A109 variants or non-A109 models.

Primary legal obligors under the AD are not named in the text beyond the issuing authority, but the requirement language (“Modify ... installing ... in accordance with the instructions of Agusta Bollettino Tecnico 109EP-98”) places a mandatory duty on the operator, owner or maintenance entity responsible for the affected aircraft to carry out the modification. The AD does not explicitly identify whether the operator, owner or another party holds the financial or logistical responsibility; the instrument simply prescribes the modification be accomplished within the prescribed timeframe. The issuing entity is the Civil Aviation Safety Authority, the AD is signed by a CASA delegate, and the AD explicitly refers to EASA for approval of later Bollettino revisions, thereby involving EASA as the technical approver of any later method-of-compliance revisions.

Maintenance providers and avionics technicians who perform the modification are directly implicated because the AD requires installation in accordance with Agusta’s Bollettino. That Bollettino will contain the engineering and procedural steps necessary to perform the modification. The AD therefore affects whoever has the authority to perform or authorise maintenance on the listed A109E helicopters, including organisations holding appropriate maintenance approvals. Part numbers appear prominently in the AD, so logistics personnel and procurement are affected: they must source the correct modification kit (P/N 109-0824-73-101) and ensure the specific assemblies (P/N 109-0741-49 and P/N 109-0741-55) are available for modification or inspected accordingly.

Regulators and auditors are implicated in two respects. First, CASA is the issuer and thus the regulator for Australian-registered aircraft; second, EASA is the body whose approval is required for later Bollettino revisions, thereby adding a technical regulator role. The AD also notes EASA AD 2009-0137 “refers,” suggesting that operators subject to EASA jurisdiction or oversight might be subject to linked or parallel requirements. The AD does not identify wider classes of stakeholders such as insurers, lessors, or third-party service providers, nor does it specify any reporting or certification steps post-modification within the AD text itself.

The AD articulates a single express duty and several procedural constraints and references which together form the required compliance regime. The central duty is mandatory: modify the fuselage electrical installation P/N 109-0741-49 and the overhead panel electrical installation P/N 109-0741-55 by installing the BATT BUS circuit breaker modification kit P/N 109-0824-73-101. The AD instructs that this installation must be carried out “in accordance with the instructions of Agusta Bollettino Tecnico 109EP-98 dated 22 June 2009 or later revision approved by the European Aviation Safety Agency (EASA).” That phrase has two practical effects: it delegates the technical method of compliance to the Bollettino, and it conditions acceptance of later procedural changes on EASA approval.

Timing is a key duty constraint. The AD requires compliance “Within 50 hours time in service after the effective date of this Directive but no later than 31 December 2009, whichever occurs first.” The effective date is stated as 7 July 2009. That creates a hard window defined by either accrued flight hours (50 hours TIS) or an absolute calendar deadline. The AD therefore imposes an operative urgency on affected operators to schedule and perform the modification promptly.

Rights and flexibilities are limited and explicitly circumscribed. The AD permits the use of a “later revision” of the Agusta Bollettino only if that revision has been approved by EASA. The AD thus grants a controlled path for amendments to the specified method of compliance, subject to external regulator approval. No other alternative methods of compliance, exemptions, or deferred compliance are offered within the AD text.

What the AD does not state is also a key procedural feature. The AD does not specify who pays for parts or labour, it does not outline record-keeping or certification entries to be made post-modification, and it does not include text on permissions for interim ferry flights or grounding procedures. The AD does not itself spell out enforcement remedies or penalties for non-compliance within its body. The instrument does, however, record its provenance and refer to related EASA action, signalling that the Bollettino’s instructions and any EASA decisions are integral to determining acceptable compliance activity.

Finally, the AD’s background note states the safety rationale that justifies the duty: the Type Certificate holder’s investigations identified inadequate functioning of the 35 Amp BATT BUS circuit breaker as the reason for an electrical failure, and the modification kit replaces the 35 Amp breaker with a 50 Amp breaker and oversized wires to prevent that unsafe condition. The background provides the policy justification the duty implements; however, the AD’s enforceable content is limited to the mechanical installation and the method-of-compliance reference.

The AD itself does not set out explicit penalties, monetary fines, or criminal sanctions for non-compliance within its text. The instrument records the issuing authority , the Civil Aviation Safety Authority , and is signed by a CASA delegate, indicating the directive’s regulatory provenance and that it is an enforceable airworthiness instrument issued by CASA. The AD states its effective date and compliance requirements, which is the standard form in which CASA and other civil aviation authorities issue mandatory airworthiness directives. However, within the text supplied there is no express provision detailing enforcement actions, civil penalties, administrative fines, suspension or revocation processes, or specific follow-up audit mechanisms.

Given that the AD is issued by CASA and becomes effective on a stated date, routine regulatory practice would ordinarily place operational responsibility on the aircraft operator or owner to ensure the AD has been complied with for the aircraft to remain airworthy. The AD requires the modification be completed within a given hours-in-service window or by an absolute date. Within the AD itself, there is no description of how CASA will verify compliance, whether operators must lodge a compliance report with CASA, or whether post-modification certification or a logbook entry is required by the AD text.

The AD references EASA in two ways: it refers to EASA AD 2009-0137 and permits later revisions of Agusta Bollettino Tecnico 109EP-98 only if approved by EASA. The interaction with EASA is procedural and technical rather than enforcement-specific in the text provided. The AD does not instruct that EASA will enforce compliance in Australia or that EASA will impose penalties.

Where the AD is silent on penalties and enforcement measures, readers should note that enforcement may be governed by broader aviation law and regulatory frameworks outside the AD text itself, but those are not set out in this instrument. The AD’s text does not speak to third-party enforcement actions, insurance consequences, or contractual remedies that might follow failure to comply. The instrument’s practical force is that it prescribes an airworthiness modification, with a clearly stated compliance window and an authoritative method-of-compliance reference. The absence of penalty text in the AD means that any enforcement consequences rely on the wider legal and regulatory framework under which CASA operates rather than on provisions embedded in this AD document.

The AD explicitly references another regulatory instrument and a foreign regulator’s approval process, creating limited cross-jurisdictional and cross-instrument interaction within its text. It states “Note: EASA AD 2009-0137 refers,” and it conditions the acceptability of “later revision[s]” of Agusta Bollettino Tecnico 109EP-98 on approval by the European Aviation Safety Agency (EASA). That creates an interaction where the technical method of compliance is anchored to a manufacturer Bollettino whose subsequent revisions must be EASA-approved before they qualify under this AD. The AD thereby imports an external technical approval gate into its compliance pathway.

The AD is silent on interactions with statutes, regulations, or directives other than EASA AD 2009-0137 and EASA approval of Bollettino revisions. It does not cite specific Australian legislation, CASA regulations, aviation safety regulation provisions, or administrative law instruments. It does not reference civil liability laws, contract law, insurance law, or workplace health and safety laws. The AD likewise does not reference standards from standards bodies or other airworthiness codes beyond the Agusta Bollettino and the EASA AD.

Because the AD mandates modification of specific part numbers and assemblies, it interacts functionally with maintenance approvals, certificated maintenance organisations, and parts procurement channels. Those interactions are operational rather than textual in the AD: the AD requires parts with particular part numbers and that the modification be performed per the Bollettino, so the availability of parts, the authority of maintenance providers to perform modifications, and the process by which mechanical work is recorded will all determine how the AD operates in practice. However, the AD text itself does not specify how maintenance approvals or parts sourcing regulations operate; it simply sets the modification requirement.

Finally, the AD’s cross-reference to EASA embeds a mechanism for later technical change: later Bollettino revisions approved by EASA can serve as allowable methods of compliance. That creates a technical regulatory interface where an external authority’s approvals alter the AD’s internal compliance choices. Beyond those references, the AD does not delineate further interactions with other laws, national or international, within the supplied text.

The AD contains a limited administrative record in the supplied text. Its identifying code is AD/A109/63, titled “Battery Bus Circuit Breaker,” with operational marking “9/2009 DM.” It is dated 30 June 2009 and signed by James Coyne, Delegate of the Civil Aviation Safety Authority. The AD states that it becomes effective on 7 July 2009. The requirement references Agusta Bollettino Tecnico 109EP-98 dated 22 June 2009 as the instructional source for the modification, and it permits the use of “later revision[s]” of that Bollettino provided those revisions have EASA approval.

The document itself notes that “EASA AD 2009-0137 refers,” but it does not include EASA’s text or any further details of subsequent amendments to the AD in the supplied copy. There is no text in the AD indicating that it supersedes or amends any earlier AD, nor is there a list of amendments to this AD itself within the supplied material. The AD does not set out a statutory process for amendment beyond the standard instrument features: a defined effective date, specified requirement and compliance window, and an allowance for EASA-approved later revisions to the Bollettino to be used in meeting the AD.

Because the AD allows later revisions of the Bollettino only if approved by EASA, the AD effectively embeds a conditional amendment pathway for the method of compliance. That is, while the AD’s primary content is fixed in its text, practitioners may rely on a newer Agusta Bollettino revision if and only if that revision receives EASA approval. The supplied AD does not report any subsequent amendments to its own text, nor does it provide a revision log, rescission clause, or sunset clause beyond the compliance deadline for this specific modification.

In short, the supplied AD’s amendment history as documented here is minimal: issuance on 30 June 2009, effective 7 July 2009, method-of-compliance anchored to Agusta Bollettino 109EP-98 dated 22 June 2009, and an allowance for later EASA-approved Bollettino revisions. No further amendment entries or historical changes are included in the material provided.

The AD as supplied does not include any litigation history. There are no references in the text to legal proceedings, judicial review, appeals against the AD, or any court decisions involving this AD. The document records the technical background (an investigation by the Type Certificate holder identifying inadequate functioning of a 35 Amp BATT BUS circuit breaker) and administrative details (signatory, dates, part numbers), but it does not report disputes, enforcement actions, or litigation arising from the AD’s issuance.

The AD notes EASA AD 2009-0137 in a cross-reference but does not provide any judicial history related to that EASA AD within the text. The absence of litigation references in the AD means that, based on the supplied material, there is no documented case law or court rulings tied to this AD recorded here.

For readers seeking litigation history, the AD does not supply such information, and any search for cases, judicial review, or appeals against the AD would need to consult external judicial records, CASA administrative records, or public legal databases. The AD itself provides no narrative of legal challenges or outcomes, nor does it summarise enforcement proceedings, penalties applied, or compliance disputes. The instrument is silent on court interventions.

The AD contains several particulars that could trip up implementers if overlooked, and the text also omits items that users often expect ADs to state explicitly. First, applicability is precise and includes both serial-number ranges and fitment conditions. For airframes up to and including S/N 11077, the AD applies only if the airframe is equipped with kit P/N 109-0812-04-101, -103, -107 or -109. For S/N 11078 to S/N 11758 inclusive, the AD applies broadly except for three serials explicitly excluded (11741, 11754 and 11757). Mistakes in reading the serial-number matrix or in logging fitted kit part numbers could lead to unnecessary work or missed compliance.

Second, the AD requires work on two specific part-numbered assemblies: fuselage electrical installation P/N 109-0741-49 and overhead panel electrical installation P/N 109-0741-55. Implementers must verify those assembly part numbers on the aircraft to determine precisely what must be modified. The AD does not reproduce the Bollettino instructions, so following the AD requires access to Agusta Bollettino Tecnico 109EP-98 dated 22 June 2009 (or a later EASA-approved revision). Failure to use the correct Bollettino revision could create non-conformance with the AD.

Third, the AD permits use of a later Bollettino revision only if that revision is approved by EASA. The AD thereby places an approval gate on method-of-compliance changes. Practically, this means implementers cannot rely on an unapproved factory revision; they must confirm EASA approval status before adopting a later Bollettino version under this AD.

Fourth, timing is tight. The compliance window is “within 50 hours time in service after the effective date” but no later than an explicit calendar date, 31 December 2009. The effective date is 7 July 2009. The dual trigger (hours-in-service or the date) creates scheduling constraints: if an aircraft flies 50 hours quickly after 7 July 2009, the modification must be completed within that shorter window. The AD does not offer extensions, deferrals, or interim flight authorisations within its text.

Fifth, the AD does not state post-modification administrative steps such as logbook entries, certification by an authorised person, or mandatory notices to CASA. Implementers often expect an AD to specify required record-keeping, but this AD is silent in that respect. Those steps may nonetheless be required under other regulatory rules or ordinary maintenance practice, but they are not mandated within this AD text.

Sixth, the AD does not address supply-side constraints. It names the modification kit P/N 109-0824-73-101 and requires replacing hardware and wires, but it does not describe availability, lead times, or whether alternative parts are acceptable. Practitioners must therefore ensure they can source the exact kit and parts referenced.

Seventh, the AD’s background states the reason for the change is inadequate functioning of a 35 Amp breaker; the AD prescribes replacing it with a 50 Amp breaker and oversized wires. While the AD states the intended mitigation, it does not detail testing, validation, or qualification steps post-installation. Implementers should not assume additional testing requirements are specified in the AD itself.

Finally, enforcement and penalty mechanisms are not described in the AD. That absence may lead to uncertainty about reporting, certification, or exposure in the event of non-compliance. Implementers must be attentive to external CASA requirements and standard airworthiness record-keeping to ensure the regulatory basis for continued airworthiness is satisfied, because the AD itself does not list these administrative steps.

The AD prescribes a concrete, limited set of steps and references for compliance. Follow these steps as set out in the AD text.

1. Determine applicability. Confirm whether the helicopter is an Agusta A109E and verify the serial number. If the serial number is S/N 11077 or below, confirm whether the aircraft is equipped with kit part number 109-0812-04-101, -103, -107 or -109; the AD applies only in that situation. If the serial number falls between 11078 and 11758 inclusive, the AD applies except for S/N 11741, 11754 and 11757 which are specifically excluded.

2. Acquire the required kit and documentation. The AD specifies the BATT BUS circuit breaker modification kit P/N 109-0824-73-101. Also obtain Agusta Bollettino Tecnico 109EP-98 dated 22 June 2009, which the AD identifies as the instructions for modification. If a later revision of that Bollettino is to be used, ensure that revision has been approved by the European Aviation Safety Agency (EASA), because the AD allows later revisions only if EASA-approved.

3. Schedule the work within the AD’s timeframe. The AD requires completion within 50 hours time in service after the AD’s effective date, or no later than 31 December 2009, whichever occurs first. The AD becomes effective on 7 July 2009. Accordingly, determine the aircraft’s time-in-service accumulation and schedule the necessary maintenance to meet the earlier of the two limits.

4. Perform the modification per the Bollettino. The AD requires modification of fuselage electrical installation P/N 109-0741-49 and overhead panel electrical installation P/N 109-0741-55 by installing kit P/N 109-0824-73-101 and replacing the 35 Amp BATT BUS circuit breaker with a 50 Amp breaker and replacing the wires with oversized ones as specified in the Bollettino instructions. The AD does not reproduce the Bollettino’s step-by-step instructions, so compliance requires strict adherence to the Bollettino’s procedures.

5. Use authorised personnel and approved facilities. Although the AD does not explicitly state maintenance authority requirements, the modification deals with primary electrical safety and airworthiness-related hardware. Standard aviation practice requires that such work be performed by appropriately authorised maintenance organisations or certificated persons, and operators should ensure the technicians carrying out the work are authorised under relevant maintenance regulations. The AD itself, however, does not specify those authorisations.

6. Confirm acceptance criteria. The AD mandates the installation “in accordance with the instructions” of the Bollettino. Confirm that the Bollettino’s acceptance criteria are met, and, if using a later EASA-approved Bollettino revision, retain documentation of EASA approval.

7. Record compliance. The AD does not state the exact post-modification administrative steps, but operators should make appropriate entries in the aircraft maintenance logbooks and retain records of parts used (including kit P/N), Bollettino revision applied, and the person or organisation that performed the work. Because the AD is an airworthiness instrument issued by CASA, operators should ensure their airworthiness records show compliance with AD/A109/63 as of the relevant date to support continued airworthiness.

8. Cross-reference related ADs. The AD notes “EASA AD 2009-0137 refers.” Operators should consult that EASA AD as relevant technical or administrative context in case it contains complementary instructions or clarifications. If any ambiguity exists between the Bollettino and the AD, the AD’s text and the Bollettino instructions (as approved by EASA where relevant) govern compliance.

9. Retain proof of compliance for regulatory review. Although the AD does not set out a reporting requirement, CASA or other authorities may request evidence of compliance in the course of audits or inspections. Maintain invoices, kit serial/part numbers, Bollettino copies, EASA approvals for later revisions if used, and logbook entries.

10. If unsure, seek clarification from CASA or Agusta. The AD identifies CASA as the issuing authority and Agusta as the Type Certificate holder and Bollettino issuer. The AD does not provide a contact or procedure for deviations or alternative method approvals beyond the EASA approval pathway for Bollettino revisions; accordingly, operators who need to deviate from the AD’s prescribed method should seek formal clarification or approval from the appropriate regulator.

Note: The AD does not indicate who bears costs for parts, labour, or logistics, nor does it set out penalties; compliance planning therefore needs to address procurement, scheduling, and record-keeping obligations under the operator’s normal regulatory obligations in addition to the AD’s explicit mechanical requirement.