AD/S-62/11 - Main Rotor Brake Disc

The AD operationalises a small set of technical and procedural concepts to address a safety issue identified by the FAA and adopted by CASA. Those concepts, as set out in the text, are:

• Applicability by part number and model: The directive applies only to "Model S-62 series helicopters, equipped with part number S6235-20213 or part number 62350-22013-101 rotor brake discs" (Applicability). Compliance therefore depends on correct identification of the part number fitted to each helicopter.

• Mandatory part replacement: The AD requires replacement of an identified rotor brake disc part number S6235-20213 with a specified alternative, part number 62350-22013-101, and requires that replacement to be accomplished "in accordance with Paragraph 2 of Sikorsky Service Bulletin (SB) 62B35-13 or SB 62B35-13A" (Requirement, para 1). The AD thus delegates procedural detail for replacement to the manufacturer's service bulletin.

• Inspections focused on cracking and installation: After replacement, the AD mandates a "detailed inspection of the part number 62350-22013-101 rotor brake disc installation and a dye penetrant inspection of the rotor brake disc for cracking" aligned with Paragraph E(2) of Sikorsky Alert Service Bulletin 62B35-12, subject to two specific changes (Requirement, para 2). This creates a retention-inspection regime rather than a single replacement-only mandate.

• Technical tolerances and torque changes: The AD alters two technical parameters from the alert service bulletin: it specifies a minimum thickness for the new disc of .449 inches and directs that the attachment bolt torque be changed as described in Figures 1 and 2 of SB 62B35-13 (Requirement, para 2). Those technical numbers become the AD’s mandatory tolerances to which inspections and replacements must conform.

• Immediate action on detection: If "cracks are evident during any Requirement 2 inspection," the AD requires replacement "before further flight" and then a resumption of the Requirement 2 inspection schedule (Requirement, para 2). That creates an absolute stop-to-flight trigger in the event of cracking.

• Timing and recurrence: Timing is two-tiered. The initial replacement is due "unless already accomplished, before 30 April 2005" (Compliance, para 1). Inspections must be performed "before the accumulation of 120 flight hours since new or the last inspection" and "thereafter at intervals not to exceed 120 flight hours" (Compliance, para 2). This defines the immediate deadline and the ongoing frequency.

• Cross-references to other documents: The AD requires adherence to Sikorsky SBs for procedural detail and references an FAA AD (FAA AD 81-06-53 R1 Amdt 39-4303), while also invoking the helicopter's "applicable maintenance manual" for replacement steps where cracking is found (Requirement, para 2; Note). Thus the AD operates by binding operators to external technical documents rather than re-stating all technical procedures.

These are the primary operational constructs the AD creates. Each is anchored to explicit text in the AD and, in practical terms, converts manufacturer guidance and FAA direction into a CASA-mandated maintenance and inspection regime with specific tolerances and a defined inspection cycle.

The AD directly binds operators of Sikorsky S-62 series helicopters that have either of the two listed rotor brake disc part numbers installed. The Applicability paragraph states the affected fleet precisely: "Model S-62 series helicopters, equipped with part number S6235-20213 or part number 62350-22013-101 rotor brake discs." Any owner or operator of a helicopter that meets that description is subject to the AD’s mandatory requirements.

Maintenance organisations and certificated maintenance engineers (AMEs) will be operationally affected because the AD prescribes procedural actions to be carried out "in accordance with Paragraph 2 of Sikorsky Service Bulletin (SB) 62B35-13 or SB 62B35-13A" and inspection work "in accordance with Paragraph E(2) of Sikorsky Alert Service Bulletin 62B35-12" (Requirement). Those organisations must have access to the specified Sikorsky service documents and the helicopter’s "applicable maintenance manual" (Requirement, para 2) to perform the required replacement and inspections in compliance with the AD.

Parts suppliers and logistics functions within operators are implicated because the AD mandates a specific replacement part: operators must obtain part number 62350-22013-101 to replace part number S6235-20213 (Requirement, para 1). The AD also alters a technical parameter (minimum thickness .449 inches) and bolt torque settings (changed per Figures 1 and 2 of SB 62B35-13) that will affect procurement specifications and maintenance checks (Requirement, para 2).

Regulators and oversight personnel will be involved in verifying compliance, since the AD is issued by the Civil Aviation Safety Authority and is effective from 14 April 2005 (AD effective date). The signature block shows the AD is issued by a CASA delegate (David Villiers), which indicates the AD sits within CASA’s regulatory instruments and that CASA expects operators to comply with the listed technical and timing requirements (signature and date).

Finally, the AD makes an express reference to FAA AD 81-06-53 R1 Amdt 39-4303 (Note). Although the AD does not itself state the legal effect of that cross-reference, the inclusion signals that operators who are fleet-common with FAA-regulated operations or who rely on FAA material will need to consult that FAA AD as part of their information set. In short, affected parties include aircraft owners/operators, maintenance providers, parts suppliers, and regulator oversight functions , all insofar as they deal with S-62 helicopters carrying the listed part numbers.

Duties imposed by the AD are explicit and prescriptive. The AD creates three core duties for affected helicopters:

1. Replacement duty: "Replace part number S6235-20213 rotor brake disc with part number 62350-22013 -101 rotor brake disc in accordance with Paragraph 2 of Sikorsky Service Bulletin (SB) 62B35-13 or SB 62B35-13A" (Requirement, para 1). The duty is to fit the specified part and to follow the procedural steps set out in the indicated service bulletin paragraph.

2. Inspection duty: "Accomplish a detailed inspection of the part number 62350-22013-101 rotor brake disc installation and a dye penetrant inspection of the rotor brake disc for cracking; in accordance with Paragraph E (2) of Sikorsky Alert Service Bulletin 62B35-12 (except that the minimum thickness for the new disc is .449 inches and the attachment bolt torque is changed per Figures 1 and 2 of SB 62B35-13" (Requirement, para 2). The AD therefore mandates both an installation check and a non-destructive test (dye penetrant) for cracking, while specifying two mandatory deviations from the alert service bulletin.

3. Immediate corrective duty on detection: "If cracks are evident during any Requirement 2 inspection, before further flight, replace the disc in accordance with the applicable maintenance manual, and resume the Requirement 2 inspections" (Requirement, para 2). This duty requires removal from service and replacement prior to any further flight if cracking is found.

Timing duties refine when those actions must occur:

• Initial replacement: "Unless already accomplished, before 30 April 2005" (Compliance, para 1).
• Inspection schedule: "Before the accumulation of 120 flight hours since new or the last inspection. Inspect thereafter at intervals not to exceed 120 flight hours" (Compliance, para 2).

Rights set out or implied in the AD are procedural and limited to the technical routes the AD prescribes. The AD gives the operator the right to comply by following the specified Sikorsky service bulletins and the applicable maintenance manual. That is, the AD directs that the replacement be performed "in accordance with Paragraph 2 of Sikorsky Service Bulletin (SB) 62B35-13 or SB 62B35-13A" and inspections "in accordance with Paragraph E(2) of Sikorsky Alert Service Bulletin 62B35-12" (Requirement). The AD thereby confines the permissible means of compliance to those documents; operators do not have an implied right within the text to substitute alternative procedures unless those alternatives are themselves authorised by the manufacturer or regulator outside the AD text.

The AD does not specify formal waiver mechanisms, alternative method approvals, or administrative avenues for relief within its text. It does cross-reference other documents (Sikorsky SBs, the applicable maintenance manual, and FAA AD 81-06-53 R1 Amdt 39-4303), which operators may consult for further procedural detail, but the AD itself prescribes the precise duties and deadlines (Applicability; Requirement; Compliance).

Who decides: Compliance decisions about when and how to perform work subject to this AD rest with the operator and the certificated maintenance organisation, insofar as they are the parties responsible for executing maintenance actions "in accordance with" the cited service bulletins and maintenance manual. CASA, via the delegate who signed the AD, decides the content and mandatory nature of the requirements and the compliance timetable (signature block and effective date).

Recording and resumption: The AD mandates resumption of the inspection regime after any replacement triggered by detection of cracks (Requirement, para 2). While the AD does not prescribe a particular form of records, the requirement to resume inspections implies a continuing duty to monitor and maintain the inspection cycle.

The AD text itself does not set out criminal penalties, administrative fines, or detailed enforcement procedures. The instrument specifies mandatory technical and timing requirements but contains no penalty clause within the printed text. It simply states the operative requirements (Replacement; Inspections; Immediate replacement if cracks found), the applicability, compliance dates, and effective date (Applicability; Requirement; Compliance; "This Airworthiness Directive becomes effective on 14 April 2005").

Because the AD is a CASA instrument and it is made effective with a delegate’s signature (David Villiers), the AD functions as an authoritative regulatory requirement within CASA’s airworthiness framework. The AD’s mandatory wording ("Replace ...", "Accomplish ...", "Inspect ...", "Before further flight, replace ...") indicates that non-compliance would mean the aircraft is not maintained in accordance with the AD. The AD does not, however, in its text specify the enforcement mechanism by which CASA would follow up non-compliance, the procedural steps for enforcement, or the sanctions applicable for failure to comply.

The AD also refers to FAA AD 81-06-53 R1 Amdt 39-4303 (Requirement Note), but it does not reproduce or restate any enforcement provisions that might be contained within that FAA AD. The interaction between CASA enforcement regimes and FAA enforcement regimes is not described in the AD.

In practice, the absence of prescribed penalties in the AD text does not mean there are no regulatory consequences for failing to comply; the AD should be read against the wider regulatory framework in which CASA issues ADs. However, because the source document provided here does not include those broader enforcement provisions, this note cannot specify the exact penalties, processes for enforcement, grounds for exemptions or alternative method of compliance approvals, or how CASA will administratively verify compliance. The AD itself is silent on these points.

The AD expressly incorporates and depends on several external technical documents as part of its operative requirements. It requires work to be done "in accordance with Paragraph 2 of Sikorsky Service Bulletin (SB) 62B35-13 or SB 62B35-13A" for the replacement task and also requires inspections "in accordance with Paragraph E (2) of Sikorsky Alert Service Bulletin 62B35-12" (Requirement, paras 1-2). Consequently, the AD operates by mandating compliance with manufacturer service bulletins and an alert service bulletin; those documents supply the procedural detail and are thus functionally part of the compliance regime established by the AD.

The AD also instructs that where cracks are found the disc must be replaced "in accordance with the applicable maintenance manual" (Requirement, para 2). This ties the AD to the helicopter’s maintenance manual and places the maintenance manual’s procedures within the chain of required compliance actions.

The AD references a FAA airworthiness directive: "Note: FAA AD 81-06-53 R1 Amdt 39-4303 refers." The AD does not reproduce the contents of that FAA AD, but the reference establishes a cross-jurisdictional link that operators may need to consider when reviewing the complete set of technical and regulatory expectations. The AD's text does not explain the legal consequences of the FAA AD in Australian regulatory terms, nor does it attempt to harmonise divergences; it only records that the FAA AD is referred to.

The AD is silent as to how it interacts with other specific Australian statutes, regulations, or civil aviation instruments beyond its own status as an Airworthiness Directive made effective by CASA. The AD does not state whether compliance with the AD leaves unaffected any other certification obligations, whether the AD modifies maintenance data approvals, or whether it creates rights of recourse against the manufacturer. Those matters fall outside the AD text as provided here.

In short, the AD creates a tripartite interaction: CASA’s directive imposes duties that must be executed pursuant to manufacturer service bulletins and the helicopter’s maintenance manual and points operators to an FAA AD for additional reference. The AD embeds these external documents as mandatory points of attachment for the technical steps and tolerances it prescribes.

The document provided is identified as AD/S-62/11 and dated 4/2005. It bears the delegate’s signature (David Villiers) and a preparatory date of 2 March 2005, with the instrument stated to become effective on 14 April 2005. The Compliance paragraph sets two temporal milestones: initial compliance "before 30 April 2005" unless already accomplished, and recurring inspection intervals "not to exceed 120 flight hours" (Compliance, paras 1-2). The AD text also includes an internal note that "FAA AD 81-06-53 R1 Amdt 39-4303 refers" (Requirement Note).

The AD text as provided does not include any explicit amendment history entries, prior versions, replacement texts, or superseded AD references (other than the FAA AD reference). There is no record in the instrument of prior Australian ADs that it amends or supersedes, nor is there a provision in the text that amends earlier CASA ADs. The identifier (AD/S-62/11) and the date code (4/2005) are the only edition indicators present.

The printed material repeats headings and the AD identifier several times (AD/S-62/11; Main Rotor Brake Disc; 4/2005), but these repetitions do not constitute an amendment history. No subsequent amendments, revocations, or update clauses are included in the text provided.

Operators must treat this document, dated as above and effective 14 April 2005, as the operative AD until a later instrument expressly amends or revokes it. The AD’s internal references to Sikorsky service bulletins and the FAA AD may themselves have amendment histories, but those are not included in the text of this AD and are not summarised in the document provided.

The Airworthiness Directive text supplied does not include or reference any litigation, legal proceedings, judicial determinations, or case law. It does not cite any court decisions, nor does it assert that any specific legal challenge has been mounted against it. The document is a regulatory instrument recording technical requirements and compliance timing; it contains no litigation record.

Because the source is silent on litigation, there is no litigation history that can be reported from this AD itself. The AD does reference an FAA AD (FAA AD 81-06-53 R1 Amdt 39-4303) and Sikorsky service bulletins, but the AD does not indicate any court adjudications arising from those documents either. Any judicial or administrative proceedings concerning the AD, its enforcement, or the underlying technical issues are not mentioned in the text and therefore cannot be stated here.

Users seeking litigation history would need to consult external legal databases, CASA enforcement records, or court registries. None of those sources or any litigation references appear in the AD document provided.

The AD contains a number of points where operators and maintenance providers commonly make errors or where practical implementation raises issues. The following are concrete matters drawn from the AD text that require attention:

• Narrow applicability by part number. The AD applies only to helicopters "equipped with part number S6235-20213 or part number 62350-22013-101 rotor brake discs" (Applicability). Misidentifying the part number on an aircraft will lead to either unnecessary work or failure to comply. Operators must verify part numbers precisely; the AD’s language leaves little room for interpretation on that point.

• Replacement direction is to a part number that is also listed in the Applicability. The AD requires replacement of part S6235-20213 with part 62350-22013-101 (Requirement, para 1), yet the Applicability lists both part numbers as triggers. That suggests an aircraft fitted already with the new part number may still be caught by the AD and therefore subject to the inspection requirements. Operators should not assume that having part 62350-22013-101 fitted eliminates further duties; the AD explicitly requires inspections of the part number 62350-22013-101 installation and a dye penetrant inspection (Requirement, para 2).

• Mandatory deviations from the Alert SB. The inspection requirement is "in accordance with Paragraph E (2) of Sikorsky Alert Service Bulletin 62B35-12", but with two mandatory changes: "the minimum thickness for the new disc is .449 inches and the attachment bolt torque is changed per Figures 1 and 2 of SB 62B35-13" (Requirement, para 2). Implementers must ensure those two deviations are applied; following the Alert SB alone without applying these specified changes will not satisfy the AD text.

• Immediate "before further flight" replacement trigger. If cracks are found during any required inspection, the AD requires replacement "before further flight" (Requirement, para 2). That creates an immediate operational stoppage for that aircraft until replacement is accomplished. Operators must be prepared for removal-from-service, potential flight cancellations and logistics to obtain the replacement part.

• Timing narrowness for initial replacement. The AD requires the replacement "unless already accomplished, before 30 April 2005" (Compliance, para 1) and the AD itself takes effect on 14 April 2005. The window between effective date and the initial compliance date is short. Operators would need to schedule the replacement promptly within that timeframe.

• Recurring inspection cadence may affect utilisation. The AD requires inspections "before the accumulation of 120 flight hours since new or the last inspection" and thereafter "at intervals not to exceed 120 flight hours" (Compliance, para 2). Operators should integrate these checks into maintenance planning and logbooks to avoid missing the inspection window. Failure to track flight hours precisely against the inspection schedule would constitute non-compliance.

• Dependency on external documents. The AD delegates procedural detail to Sikorsky SB 62B35-13/13A and Alert SB 62B35-12, and to the "applicable maintenance manual" for replacement where cracking is found (Requirement). Those documents are external to the AD and may contain essential procedural steps, figures and torque values. Operators must obtain and strictly follow those documents as modified by the AD text.

• Reference to FAA AD without detail. The AD notes "FAA AD 81-06-53 R1 Amdt 39-4303 refers" (Requirement Note). The source AD does not reproduce that FAA AD’s content. Operators who rely on FAA guidance should obtain and review that FAA AD in full; omission of that step may leave gaps in understanding any additional recommended or required steps.

• Record-keeping expectations are implicit, not explicit. The AD directs actions and inspection cycles but does not specify the form of evidence or records to be maintained. Operators should nevertheless ensure that maintenance records clearly document compliance with the AD, the inspections, any findings of cracking, and any replacements done "in accordance with the applicable maintenance manual" as required by the AD (Requirement, para 2), because the AD itself will be enforced through CASA oversight mechanisms outside the text.

These are not speculative risks; each flows directly from the textual requirements, timing, and cross-references that the AD establishes.

This section sets out a practical sequence of actions an operator or maintenance organisation should take to comply with the AD, strictly reflecting the AD’s text and its specific cross-references.

1. Confirm applicability. Inspect the helicopter’s parts and logbook to determine whether the main rotor brake disc installed is part number S6235-20213 or part number 62350-22013-101 (Applicability). The AD’s duties attach only if one of those part numbers is fitted.

2. Obtain the referenced documents. Acquire Sikorsky Service Bulletin 62B35-13 or 62B35-13A (Paragraph 2), Sikorsky Alert Service Bulletin 62B35-12 (Paragraph E(2)), and the helicopter’s applicable maintenance manual. The AD makes compliance contingent on performing work "in accordance with" those documents (Requirement, paras 1-2).

3. Schedule and perform the mandated replacement. Where the helicopter is fitted with part number S6235-20213, replace it with part number 62350-22013-101 "in accordance with Paragraph 2 of Sikorsky Service Bulletin (SB) 62B35-13 or SB 62B35-13A." The AD requires this replacement "unless already accomplished, before 30 April 2005" (Requirement, para 1; Compliance, para 1). Document the replacement in the aircraft’s maintenance records.

4. Perform the required inspections. After replacement (or where the helicopter already has part 62350-22013-101 fitted), "accomplish a detailed inspection of the part number 62350-22013-101 rotor brake disc installation and a dye penetrant inspection of the rotor brake disc for cracking; in accordance with Paragraph E (2) of Sikorsky Alert Service Bulletin 62B35-12" (Requirement, para 2). However, apply the AD’s two specified modifications to that Alert SB: ensure the new disc meets the minimum thickness of .449 inches, and apply the attachment bolt torque changes as specified in Figures 1 and 2 of SB 62B35-13 (Requirement, para 2).

5. Act immediately on detection of cracking. If any inspection required by Requirement 2 reveals cracking, "before further flight, replace the disc in accordance with the applicable maintenance manual, and resume the Requirement 2 inspections" (Requirement, para 2). Record the finding, the immediate grounding action, and the subsequent replacement work in the maintenance log.

6. Observe the inspection interval. The AD requires that initial and routine inspections be timed "before the accumulation of 120 flight hours since new or the last inspection. Inspect thereafter at intervals not to exceed 120 flight hours" (Compliance, para 2). Integrate this interval into the aircraft’s maintenance scheduling and flight hour tracking systems so that no inspection window is missed.

7. Record compliance. While the AD does not set a prescribed form of evidence, operators should create a clear audit trail showing (a) date and nature of replacement work (including part numbers changed), (b) inspection dates, methods used (dye penetrant), results, and any corrective action taken, and (c) references to the specific paragraphs of the Sikorsky SBs and the maintenance manual relied upon, as modified by the AD’s specified tolerance changes (.449-inch minimum thickness; bolt torque per SB 62B35-13 figures).

8. Review FAA AD reference. The AD notes "FAA AD 81-06-53 R1 Amdt 39-4303 refers" (Requirement Note). Operators should obtain and review that FAA AD for any additional technical content or clarifications that may be relevant to the aircraft and its parts, while ensuring that the actions taken comply with the Australian AD’s explicit modifications.

9. Allocate parts, labour and scheduling. The AD’s timing provisions (initial replacement before 30 April 2005, 120 flight-hour inspection intervals) mean operators should plan parts procurement and maintenance slots promptly to meet short initial deadlines and recurring inspections. The AD requires specific torque settings and thickness verification, so tooling and measurement capacity must be checked as part of planning.

10. Maintain readiness to remove from service. The AD’s "before further flight" replacement requirement on detection of cracks means maintenance organisations and operators must have procedures to ground the aircraft immediately, obtain replacement parts and effect the replacement, and then resume the inspection regimen. This should be reflected in operational contingency plans.

Following these steps will ensure that the specific procedural and timing requirements set by the AD are observed. All actions must be documented in the aircraft’s maintenance records and carried out "in accordance with" the named Sikorsky documents and the applicable maintenance manual, subject to the AD’s specified technical changes.