AD/BEECH 55/97 - Circuit Breaker Toggle Switches

The Directive’s central technical concept is an equipment safety retrofit: removal of a set of older circuit breaker toggle switches (P/N range 35-380132-1 through 35-380132-53) and replacement with an improved part series (P/N range 35-380132-61 through 35-380132-113). The replacement must be completed using the procedures and parts specified in two manufacturer service bulletins: Hawker Beechcraft SB 24-3807 (May 2007) and Raytheon Aircraft Company (RAC) SB 24-3735 (August 2005). The AD makes later FAA-approved revisions of those service bulletins acceptable if they are approved as an AMOC to the related FAA AD (FAA AD 2008-13-17), thus tying compliance routes to FAA regulatory approvals.

Applicability is defined by model and serial number ranges shown in Table 1, and the Directive’s Applicability line makes clear it applies only where the older P/Ns are installed. The Table 1 content is part of the operative applicability: models listed include 95-B55, D55, E55, 58, 58P, 58TC, G58 (and serial number ranges specified) and the Directive’s Background extends the inventory of affected models to many other Beech models where reports were received. The hazard identified in the Background is overheating of circuit breaker toggle switches used “in various electrical systems throughout” a list of models; the failure mode identified is “smoke in the cockpit and the inability to turn off the switch.” The AD therefore frames the replacement as mitigation of a fire/smoke and loss-of-control-of-electrical-circuit risk.

Two compliance timing concepts are embedded: a time-limited retrospective compliance obligation (replace within 24 months of the AD’s effective date), and an ongoing prohibition on reinstalling the older P/Ns (no initial-fit or replacement-spare installation of P/Ns 35-380132-1 through -53). The AD also provides for recognition of “prior accomplishment” , if the service bulletin actions were already done, the Requirement is satisfied , and it explicitly recognises that the RAC service bulletin was issued in 2005 and may already have been accomplished.

Interoperability with FAA regulatory instruments is explicit: the AD references FAA AD 2008-13-17 and states that FAA-approved AMOCs to that FAA AD are acceptable for compliance with the Australian Directive. The Directive thus creates a compliance pathway that relies on FAA technical approval of service bulletin revisions.

Finally, the Directive is administrative in form: it was issued by CASA, signed by James Coyne as a delegate, a draft was posted for public comment on 9 July 2008 and “no comments or objections have been received” as of issuance.

Primary affected parties are owners and operators of the specific Beechcraft aeroplane models and serial number ranges listed in Table 1 where one or more circuit breaker toggle switches with P/N 35-380132-1 through 35-380132-53 are installed. The Applicability line states: “Aeroplane models and serial numbers listed in Table 1 that have any circuit breaker toggle switch with a part number (P/N) 35-380132-1 through 35-380132-53 installed.” Table 1 lists model identifiers (e.g. 95-B55, D55, E55, 58, 58P, 58TC, G58) with detailed serial number ranges. The Background paragraph expands the set of models in which the problem was reported, naming many Beech models including F33, F33A, F33C, G33, V35B, A36, A36TC, B36TC, 95-B55, D55, E55, A56TC, 58, 58P, 58TC, G58 and 77; that paragraph explains the FAA received reports of overheating across various electrical systems in those models. Practically, any operator of an aircraft listed in Table 1 must check whether the specified P/Ns are fitted.

Maintenance organisations, licensed aircraft maintenance engineers, and parts suppliers are also affected. Requirement 1 mandates replacements “as specified” in two named manufacturer service bulletins; the work must follow those SBs or later FAA-approved AMOCs. Requirement 2 imposes a supplier/maintenance obligation: “Circuit breaker toggle switches P/N 35-380132-1 through 35-380132-53 may not be installed on any aeroplane as an initial fit or as a replacement spare.” That forbids aircraft technicians and parts suppliers from fitting or providing the older P/Ns as replacements or initial installations on any aeroplane subject to the Directive.

Regulatory decision-makers are identified in the document: the Directive is issued by the Civil Aviation Safety Authority (CASA), with the signature block naming James Coyne as “Delegate of the Civil Aviation Safety Authority.” The Directive references FAA AD 2008-13-17 and ties acceptance of alternate compliance methods to FAA approvals, so holders of certificates and engineers will need to interface with FAA-approved AMOCs if they seek alternative technical compliance approaches.

Finally, the source records that a draft was posted on CASA’s internet site on 9 July 2008 and “no comments or objections have been received by CASA” up to issuance. That indicates the public consultation stage recorded in the document attracted no responsive input as of the signing date, but it does not remove the compliance obligations set out in the operative Requirements.

The Directive imposes two primary duties on affected operators and maintenance parties and provides a limited compliance pathway linked to manufacturer service bulletins and FAA AMOCs.

Duties

• Identification duty: Operators must determine if their aeroplane(s) are listed in Table 1 and whether any installed circuit breaker toggle switch has P/N 35-380132-1 through 35-380132-53. The Applicability clause conditions the AD’s scope on both model/serial number and installed part numbers.

• Replacement duty (Requirement 1): Unless previously accomplished, replace all circuit breaker toggle switches P/N 35-380132-1 through 35-380132-53 with improved P/Ns 35-380132-61 through 35-380132-113, “as specified in Hawker Beechcraft Recommended Service Bulletin SB 24-3807, Issued: May 2007 and Raytheon Aircraft Company (RAC) Recommended Service Bulletin SB 24-3735, Issued: August 2005.” The Directive’s language makes the SB procedures the specified method of accomplishing the replacement.

• Prohibition duty (Requirement 2): Do not install the older P/Ns (35-380132-1 through -53) on any aeroplane as an initial fit or as a replacement spare. The timing clause for this duty is “Before further flight after the circuit breaker toggle switch has been replaced in accordance with Requirement 1,” creating an immediate operational constraint following replacement work.

• Timing duty: Comply with Requirement 1 within 24 months after the AD’s effective date (the AD “becomes effective on 25 September 2008” and the Compliance line states the time limit). This creates a retrospective compliance window that operators must observe.

Rights and pathways

• Prior accomplishment: The AD explicitly recognises “prior accomplishment,” meaning if the service bulletin actions have already been carried out, the Requirement is satisfied. That reduces duplication where operators already implemented the retrofit under earlier service bulletins.

• AMOC acceptance: The Directive allows later revisions of the listed service bulletins to be acceptable, but only where those later revisions are “approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-17.” This gives operators a specific rights-based pathway to use revised manufacturer instructions, but makes acceptance contingent on FAA approval as an AMOC to the identified FAA AD. The AD’s text states such FAA-approved SB revisions are “considered acceptable for compliance with the equivalent Requirements of this Directive.”

• Reference to FAA AD: The Directive includes a Note pointing to FAA AD 2008-13-17 Amdt 39-15580. This links the Australian AD to the FAA’s regulatory instrument and indicates that the FAA’s compliance structure and AMOC process are relevant to Australian compliance choices under this Directive.

Procedural context

• The AD was posted as a draft for comment on 9 July 2008 and the final was issued 8 August 2008 and became effective 25 September 2008. The signature is by a CASA delegate. The Directive therefore imposes binding duties from its effective date as set out in the Compliance lines.

All the duties, rights and pathways above are taken directly from the AD’s Applicability, Requirement, Compliance, Background and Note passages.

The Directive text itself does not set out specific monetary penalties, sanctions or enforcement procedures. The document is an Airworthiness Directive issued by CASA and states the AD “becomes effective on 25 September 2008,” signed by James Coyne as “Delegate of the Civil Aviation Safety Authority.” The AD contains operative Requirements and compliance timelines but does not include a penalty schedule, compliance inspection regime, or enforcement mechanisms in the body of the text provided.

From the text it is possible to identify enforcement-related facts that arise from the AD’s structure:

• The AD is an official CASA directive with an effective date; compliance is therefore an obligation imposed under CASA’s regulatory framework. The document’s formal character and signature indicate an administrative instrument, and the Compliance paragraph establishes mandatory timelines.

• The AD ties acceptable alternative compliance methods to FAA approval of revised service bulletins as AMOCs. That creates a technical compliance gate: operators seeking to use revised SBs must obtain FAA AMOC approval for those SB revisions to have the AD’s stated acceptability.

• The AD does not specify consequences for non-compliance within the text supplied. It also does not specify a process for CASA to verify completion (for example, inspection or documentation requirements), nor does it record any specific enforcement notices or penalty amounts.

Readers should therefore note the document imposes mandatory technical and timing duties, but the text does not itself state the enforcement instruments (such as notices, suspension of certificates or fines). Enforcement typically flows from CASA’s broader legislative powers and enforcement policies rather than from the AD textual content; however, those broader powers are not contained in the source provided and therefore are not described here.

The AD explicitly interacts with United States FAA regulatory instruments and manufacturer service bulletins. The Directive references FAA AD 2008-13-17 (Amdt 39-15580) and ties acceptability of later service bulletin revisions to FAA approvals. The text states: “Later revisions of the above SBs, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-17, are considered acceptable for compliance with the equivalent Requirements of this Directive.” The AD also includes a Note: “FAA AD 2008-13-17 Amdt 39-15580 refers.” That creates an explicit cross-reference to FAA regulatory action.

The Directive requires compliance “as specified in Hawker Beechcraft Recommended Service Bulletin SB 24-3807, Issued: May 2007 and Raytheon Aircraft Company (RAC) Recommended Service Bulletin SB 24-3735, Issued: August 2005.” By specifying these manufacturer SBs as the method for accomplishing the required replacement work, the AD integrates those technical documents into the legal compliance regime. It also allows later revisions of those SBs to be used if they have FAA AMOC approval.

The Background notes the AD “follows the intent of the FAA Directive” but modifies the FAA's compliance timeline, extending the compliance period by 13 months relative to the FAA’s final compliance date of 6 August 2009 (the AD extends to 25 September 2010). That illustrates a mechanism whereby CASA aligns with FAA technical findings but exercises discretion on compliance timing.

The AD’s linkage to FAA ADs and FAA-approved AMOCs effectively delegates part of the technical review function to FAA processes: operators seeking to rely on a later revision of a service bulletin must ensure that revision has FAA AMOC approval in relation to FAA AD 2008-13-17. The Directive thereby establishes an acceptance relationship between CASA’s AD compliance routes and FAA AMOC approvals.

The source does not reference any Australian statutes, regulations or instruments other than the CASA signature block and the posting for public comment on CASA’s internet site. It does not include cross-references to Australian Civil Aviation safety regulations or enforcement statutes within the text provided. Any interaction with other Australian laws or CASA’s enforcement powers is not set out in the supplied document.

The source provides a narrow amendment history relevant to the Directive’s genesis and timing, and it documents the service bulletin issuance dates that underpin the AD’s technical requirements.

Key timeline items in the source:

• RAC Service Bulletin SB 24-3735 was issued in August 2005. The AD notes the RAC SB “was issued in 2005 and may have already been accomplished,” which is the basis for recognising “prior accomplishment” as satisfying Requirement 1 where applicable.

• Hawker Beechcraft Recommended Service Bulletin SB 24-3807 was issued in May 2007. The AD specifies this SB together with the RAC SB as the specified procedures for replacement.

• The FAA issued AD 2008-13-17, amendment number 39-15580; the AD references that FAA AD in its Note and links the Australian compliance pathway to FAA AMOC approvals for later SB revisions. The AD does not itself reproduce amendment details of FAA AD 2008-13-17 beyond the reference.

• CASA posted a draft of this Directive for public comment on 9 July 2008. The final Directive text is dated 8 August 2008 with the effective date of 25 September 2008. The AD states “no comments or objections have been received by CASA” as of the date it was made.

• The AD states it “extends compliance by 13 months until 25 September 2010,” relative to the FAA’s final compliance time of 6 August 2009. The Compliance paragraph in the Directive sets the required compliance for Requirement 1 “Within the next 24 months after the effective date of this Directive.” Given the effective date of 25 September 2008 stated elsewhere in the document, that yields the 25 September 2010 deadline referenced in the Background narrative.

• The AD allows “Later revisions of the above SBs, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-17,” to be used as acceptable compliance methods. This creates an ongoing mechanism for amendment of the procedural route to compliance via FAA AMOC approvals.

The document does not record any subsequent amendments to the AD itself, nor does it list later CASA-issued revisions. The record within the source therefore captures issuance, the incorporated SB dates, linkage to the FAA AD and the stated extension of the FAA compliance deadline by CASA.

The source contains no litigation history. It records administrative steps leading to issuance , a draft posting for public comment on 9 July 2008 and a statement that “no comments or objections have been received by CASA” as of the date the Directive was made. The document is dated 8 August 2008 and signed by James Coyne as Delegate of CASA. Beyond that administrative record, there is no mention of petitions, legal challenges, appeals, tribunal decisions or court cases in the provided text.

Because the Directive cross-references FAA AD 2008-13-17, any litigation or challenge relating to the FAA AD or the underlying service bulletins is outside the scope of the source and not recorded here. The AD does not include procedural instructions for review or appeal of the Directive itself, nor does it list any dispute resolution or enforcement action history.

Practitioners should therefore treat this source as containing no litigation history; any further enquiry into challenges or judicial review would require search of CASA records, court databases, or later CASA publications, which are not present in the supplied text.

Several practical interpretation and implementation pitfalls arise directly from the text.

1. Wording inconsistency in the Background paragraph. The Background states: “This Directive follows the intent of the FAA Directive, requiring the replacement of circuit breaker toggle switches with a P/N 35-380132-1 through 35-380132-53.” That phrasing, taken at face value, would read as requiring replacement with the older P/N range. However, the operative Requirements clearly require replacement of the older P/Ns 35-380132-1 through 35-380132-53 with improved P/Ns 35-380132-61 through 35-380132-113. The Requirements and Compliance paragraphs are the operative obligations: follow the Requirements language when deciding compliance steps. The Background sentence therefore appears to contain a drafting inconsistency; the Requirements control the legal duty.

2. Applicability conditional on installed parts. The AD’s Applicability line limits the Directive to “Aeroplane models and serial numbers listed in Table 1 that have any circuit breaker toggle switch with a part number (P/N) 35-380132-1 through 35-380132-53 installed.” That means an aircraft on the model/serial list but without the older P/Ns fitted is outside the AD’s active scope. Operators need to inventory installed P/Ns rather than rely solely on model/serial listing.

3. Serial number parsing required. Table 1 lists models and serial-number ranges in non-standardised typography (e.g. “TC-1936 through TC-2456” and composite ranges like “TH-2126, TH-2127, TH-2131 through TH-2134, … TH-2143 through TH-2150”). Accurate identification requires careful matching of an aircraft’s serial group to the listed ranges. Practitioners should not assume all aircraft of a given model are included.

4. Timing and extension nuances. The AD extends compliance beyond the FAA’s final compliance time; the AD’s Compliance section requires action “Within the next 24 months after the effective date of this Directive,” and the Background notes the extension by 13 months until 25 September 2010 versus the FAA’s 6 August 2009 final compliance date. Operators relying on FAA timeframes must confirm CASA’s timeline in this AD.

5. AMOC dependence on FAA approval. The AD accepts later revisions of the SBs only if they are “approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-17.” That acceptance is conditional on FAA administrative action; CASA does not unilaterally accept every SB revision. Operators who want to rely on revised SB procedures must ensure those revisions have FAA AMOC approval related to FAA AD 2008-13-17 , do not presume an SB revision is automatically acceptable to CASA.

6. Replacement prohibition timing scope. Requirement 2 states that P/Ns 35-380132-1 through -53 “may not be installed on any aeroplane as an initial fit or as a replacement spare.” The Compliance note for Requirement 2 reads “For Requirement 2 - Before further flight after the circuit breaker toggle switch has been replaced in accordance with Requirement 1.” That is functionally an immediate operational prohibition once replacements are done, but it may create questions for maintenance that occurs prior to AD compliance or for spares inventories. Operators should ensure spares with the older P/Ns are not installed after the relevant replacement work and must adjust procurement practices to avoid obtaining prohibited P/Ns for fitted use.

7. Documentation and demonstration of “prior accomplishment.” The AD allows prior accomplishment to satisfy Requirement 1, referencing that the RAC SB was issued in 2005 and “may have already been accomplished.” The AD does not prescribe what documentary evidence suffices to prove prior accomplishment. Operators should retain records of SB compliance and parts installed to demonstrate that a replacement was previously completed in accordance with the specified SBs.

8. Unspecified enforcement mechanism. The AD sets obligations but does not include enforcement or penalty text in the supplied source. Operators should not assume the AD contains its own penalty schedule; compliance expectations are mandatory, but enforcement occurs through CASA’s broader regulatory powers, not through clauses in this AD text.

Each of these points derives from text in the Applicability, Requirement, Compliance and Background passages of the Directive and reflects potential practical pitfalls for operators, maintenance organisations and parts suppliers.

Follow the Directive’s operative statements exactly; the source provides a clear sequence and conditional acceptance steps.

1. Identify applicability. Check whether your aeroplane’s model and serial number appear in Table 1 of the Directive. The Applicability text conditions the AD on the presence of any circuit breaker toggle switch with P/N 35-380132-1 through 35-380132-53. If your model/serial is not in Table 1, the Directive does not apply as written. If it is, proceed to step 2.

2. Inventory installed parts. Inspect the aeroplane and confirm whether any circuit breaker toggle switch installed has a P/N in the range 35-380132-1 through 35-380132-53. Only aircraft on Table 1 that have those P/Ns installed are within the AD’s active scope.

3. Establish whether prior accomplishment applies. If replacement work consistent with the specified service bulletins has already been done on the aeroplane, the AD recognises “prior accomplishment” and Requirement 1 is satisfied as stated in the Directive. Retain documentary proof of the prior compliance , records of parts replaced and SB references , so compliance can be demonstrated.

4. If replacement is required, use the specified procedural documents. Requirement 1 mandates replacement “as specified in Hawker Beechcraft Recommended Service Bulletin SB 24-3807, Issued: May 2007 and Raytheon Aircraft Company (RAC) Recommended Service Bulletin SB 24-3735, Issued: August 2005.” Perform the work in accordance with the procedures and parts lists in those SBs, and ensure the replacement parts used are P/N 35-380132-61 through 35-380132-113 as required.

5. Observe the compliance time. The Directive requires Requirement 1 actions to be completed “Within the next 24 months after the effective date of this Directive.” The AD’s effective date is 25 September 2008. Work must therefore be done by 25 September 2010 unless already accomplished. Plan maintenance resources and procurement of improved P/N parts accordingly to meet that window.

6. Do not reinstall older P/Ns. Requirement 2 states “Circuit breaker toggle switches P/N 35-380132-1 through 35-380132-53 may not be installed on any aeroplane as an initial fit or as a replacement spare.” Ensure procurement and parts inventory practices prevent fitting of the older P/Ns. The Compliance note for Requirement 2 specifies the timing: this prohibition applies “Before further flight after the circuit breaker toggle switch has been replaced in accordance with Requirement 1.”

7. If relying on later service bulletin revisions, confirm FAA AMOC approval. The Directive permits later revisions of the named SBs “approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-17” to be used as acceptable compliance. If you intend to use a later SB revision rather than the SB editions expressly named in the Directive, obtain documentation of FAA AMOC approval in relation to FAA AD 2008-13-17 and retain that approval evidence with maintenance records.

8. Record keeping. Although the AD does not provide a specified form for record-keeping in the supplied text, demonstrate compliance by retaining (1) parts-sourcing documentation showing use of P/N 35-380132-61 through -113, (2) maintenance release showing work was done in accordance with the specified SBs or FAA AMOC, and (3) serial number identification showing the aircraft was within Table 1 applicability. If relying on prior accomplishment, keep the documentation evidencing that earlier work.

9. Communicate to maintenance and supply chains. Advise maintenance personnel and spares suppliers not to install older P/Ns (35-380132-1 through -53) as initial fit or replacement spares. Update procurement specifications, store inventories and maintenance procedures so that only allowable P/Ns are fitted post-compliance.

10. Monitor for FAA AMOCs or CASA further guidance. Given the AD’s conditional acceptance of later SB revisions with FAA AMOC approval, practitioners should monitor FAA AD 2008-13-17 AMOC decisions and relevant SB revisions if they prefer to use a later SB revision. Also track any subsequent CASA communications that might alter compliance routes; the Directive itself accepted AMOCs only if approved by the FAA.

All steps above correspond to the Applicability, Requirement, Compliance and AMOC acceptance language in the Directive text.