AD/CFM56/9 Amdt 1 - HPTR Fan Disk Inspection

The AD rests on a small set of interlocking technical and regulatory concepts that determine compliance obligations.

• Applicability by engine family and part number. The AD confines its scope to HPTR fan discs fitted in specified CFM56 engine variants (CFM56‑2, ‑2A, ‑2B, ‑3, ‑3B and ‑3C). It identifies the affected components by seven discrete part numbers and by serial numbers listed in Table 1 of the applicable CFMI Service Bulletin. Compliance therefore requires cross‑referencing an operator’s engine configuration and maintenance records with the part numbers and serial numbers in the SB Table 1 (Applicability; Requirement).

• Inspection method and procedural incorporation. The AD prescribes an eddy‑current inspection technique and incorporates manufacturer Service Bulletins by reference, instructing operators to perform inspections “in accordance with” the SB specified for the relevant engine family. The SBs cited carry specific dates and revision identifiers; the AD does not reproduce SB technical content but makes conformity to those SBs mandatory (Requirement).

• Removal from service criterion. The AD does not permit repair in the case of crack or gouge; any HPTR disc found cracked or gouged “are to be removed from service.” That is an absolute disposition instruction in the AD (Requirement).

• Timing and retrofit window. The AD establishes a short compliance window, requiring inspection within 30 days after the effective date unless the action was previously accomplished. The AD’s effective date is 6 July 2006; the signed document is dated 24 May 2006. The amendment also notes that the compliance period was revised to ensure that discs were not omitted due to an earlier typographical error in a part number (Compliance; Amendment note; signature block).

• Triggering incident and focus. The background explains the safety rationale: a routine shop eddy current inspection revealed a crack in a rim bolt hole; the crack initiated at a gouge produced by a drill break during manufacture. As drafted, the AD’s technical focus is therefore on bolt‑hole integrity and detection of cracks/gouges that may act as initiation sites (Background).

• Cross‑reference to another authority. The AD notes that DGAC AD 97‑327(B) “refers,” establishing a link to another airworthiness directive (Requirement, Note). The AD does not reproduce or explain the DGAC AD; it leaves operators to consult that instrument as applicable.

Taken together, these concepts mean the AD is component‑specific, procedure‑driven via incorporation of manufacturer SBs, short‑deadlined, and prescriptive on disposition. Compliance requires administrative steps (identification of affected serial numbers) and technical work (eddy‑current inspections per the SBs), plus removal of any non‑conforming parts.

The AD explicitly names the set of engine types and component part numbers to which it applies, thereby identifying who is directly impacted.

• Aircraft operators using CFMI CFM56 engines of the models listed (CFM56‑2, ‑2A, ‑2B, ‑3, ‑3B, ‑3C) will be affected where an aircraft’s HPTR fan disc matches one of the part numbers and serial numbers listed in Table 1 of the applicable CFMI Service Bulletin (Applicability; Requirement). For such operators, the AD imposes a mandatory maintenance action with a 30‑day compliance window.

• Maintenance organisations, heavy maintenance shops and approved maintenance providers that perform eddy‑current inspections and overhauls on the specified engines will be secondarily affected because the AD prescribes an inspection procedure to be performed “in accordance with” specific CFMI SBs. Those organisations must allocate resources to perform inspections within the timeframe and to document the results consistent with the operator’s regulatory obligations (Requirement; Compliance).

• Parts inventory managers and spare parts holders who stock HPTR fan discs with the listed part numbers must identify whether their inventory items match serial numbers in Table 1 and ensure that inventory parts are inspected or segregated as required. The AD’s removal‑from‑service instruction for cracked or gouged discs imposes a handling and disposition obligation for spare parts matching the affected serial numbers (Requirement).

• Manufacturers and component suppliers are implicated in a narrow sense because the AD incorporates CFMI Service Bulletins; the AD notes a manufacturing drill break as the genesis of a gouge that later initiated cracking (Background). The amendment also corrects a typographical error in a part number that could have led to omission of discs from inspection, which is an operational issue for supply chain and parts documentation (Amendment note).

• Regulatory administrators: the AD is issued by the Civil Aviation Safety Authority through a named delegate. CASA, its delegates and the approval mechanisms for continuing airworthiness implement and enforce such directives, so CASA and its delegates are stakeholders in issuance and recordkeeping (signature block).

Who does not appear in the AD text: the AD does not specify consequences for third parties such as lessors, insurers, or passengers. It also does not explicitly address OEM warranty claims or compensation flows; it merely mandates inspection and removal from service of cracked or gouged parts.

In summary, the direct burden falls on operators and maintenance providers that possess HPTR discs of the listed part numbers and serial numbers installed in the specified engine variants, and on any entity holding such parts in inventory. The AD’s incorporation of particular SBs means those maintenance organisations must use the procedural content of the SB chosen for the engine family.

The AD sets out discrete duties for affected parties and leaves the remedial details to incorporated Service Bulletins. It does not create express procedural exceptions or carveouts in its own text.

Duties (explicit in the AD text)

• Identification: Determine whether installed or stocked HPTR discs are of the part numbers and serial numbers listed in Table 1 of the applicable CFMI Service Bulletin (Requirement; Applicability). The AD implicitly requires review of maintenance and inventory records to make that determination.
• Inspection method and standard: Perform an eddy current inspection of all identified HPTR discs “in accordance with” the relevant CFMI Service Bulletin for the engine variant (Requirement). The AD makes the manufacturer’s SBs the operative technical procedures for the inspection.
• Timing: Complete the inspection within 30 days after the effective date of the AD, unless the action was already accomplished prior to that date (Compliance). The AD’s effective date is 6 July 2006 (Compliance; signature block).
• Disposition of findings: Remove from service any HPTR discs that are found to be cracked or gouged during inspection (Requirement). The AD mandates removal; it does not provide for repair options within the AD text.
• Cross‑reference obligations: Where applicable, take account of any DGAC AD 97‑327(B) that “refers” in this AD (Requirement, Note). The AD does not further unpack that referral; it is an obligation to consider related directives.

Rights and limits (what the AD does not grant or stipulate)

• No explicit authorisation for alternative methods of compliance (AMOCs) appears in the AD text. The AD prescribes the SB procedures as the means of compliance and gives a fixed compliance window (Requirement; Compliance).
• The AD does not state any appeals process, waiver mechanism or formal exception in its own text. It does not expressly permit alternative inspection methods or deferral beyond the 30‑day period.
• The AD does not set out administrative remedies, penalties, or enforcement processes in its text. The issuing authority is identified (CASA, via a delegate), but the AD itself does not include enforcement sanctions or procedures (signature block; Penalties and enforcement section below).

Practical obligations arising from these duties

• Maintenance planning and scheduling will be necessary to meet the 30‑day window. Operators must locate and inspect relevant components and document the outcome.
• If a disc is removed from service because it is cracked or gouged, operators must follow their continuing airworthiness procedures for replacement, parts traceability and recordkeeping. The AD requires removal but leaves subsequent replacement and verification of compliance subject to routine maintenance and regulatory recordkeeping practice, as no further direction is provided in the AD text.

The AD’s amendment corrects a typographical error in a part number and states the compliance period was revised to ensure no discs were omitted from the AD’s coverage (Amendment note). That correction affects the duty of identification: operators and maintainers must ensure they use the corrected part number (1475M29P01 rather than the misprinted 147M29P01) when determining applicability.

The text of this AD does not include express penalties, monetary fines, or enforcement procedures. The document is an airworthiness directive issued by the Civil Aviation Safety Authority (CASA) and signed by a CASA delegate (James Coyne), but the AD itself contains only the safety requirement, the applicability, the mandated action, and the compliance timing (Requirement; Compliance; signature block).

What the AD does state relevant to enforcement mechanics

• Issuance and authority: The AD is an instrument of CASA, signed by a delegate, which by its nature is a regulatory safety directive (signature block). The AD’s prescriptive language requires actions “in accordance with” specified CFMI Service Bulletins and sets an imperative to remove cracked or gouged discs from service (Requirement).
• Timing for compliance: The AD prescribes a 30‑day compliance period measured from the effective date (Compliance). The existence of a firm compliance date implies a regulatory obligation to be performed within that period.

Limitations in the AD text concerning enforcement

• No adjudicative or sanctioning text: The AD does not specify civil or criminal penalties for non‑compliance, nor does it describe administrative remedies or the enforcement channels CASA may use. The AD also does not identify any notification, reporting or certification form that operators must submit to CASA upon completion of the inspections or removal actions.
• No explicit AMOC process: The AD does not state an alternative method of compliance process or waiver procedure within its own text.

Consequences arising from these observations

• Because the AD is an airworthiness directive issued by CASA, compliance is mandated by the instrument as written. The AD’s lack of embedded penalties does not mean that non‑compliance has no regulatory consequences; it means that the AD text itself does not set them out. Any enforcement mechanisms, penalties or administrative steps presumably sit within the broader regulatory framework administered by CASA and related statutes or regulations, but those instruments are not reproduced or referenced beyond the issuance and signature in this AD.

Recommended administrative stance (based strictly on the AD’s text)

• Operators should treat the AD as a mandatory safety directive with a fixed compliance window and should document inspections and removals in their maintenance records. The AD’s absolute instruction to remove any cracked or gouged discs removes operator discretion in disposition of such parts.

In short, the AD prescribes mandatory actions and a timeframe but does not itself enumerate enforcement sanctions or procedural remedies; responsibility for enforcement and any sanctioning process appears to reside outside the text of the AD and within CASA’s broader regulatory functions.

The AD text itself is focused and narrowly framed; it incorporates and cross‑references other instruments, but it does not set out an interaction with broader legislation within its text.

Incorporation of manufacturer Service Bulletins

• The AD makes compliance dependent on following specific CFMI Service Bulletins for the relevant engine family, stating that inspections are to be “in accordance with” the identified SBs (Requirement). This creates a direct operational interaction between the AD and manufacturer technical documents: the SBs become the normative procedures operators must follow to satisfy the AD.

Cross‑reference to another airworthiness directive

• The AD notes that DGAC AD 97‑327(B) refers (Requirement, Note). The AD therefore connects to at least one other AD issued by a separate airworthiness authority (DGAC). The text does not explain the substance of DGAC AD 97‑327(B) nor how compliance with it aligns with the CASA AD; it simply acknowledges the reference. Practically, operators will need to consult the referenced DGAC AD if they are to consider the full set of applicable directives.

Amendment mechanics and documentation accuracy

• The AD contains an amendment correcting a typographical error in a part number. The correction (changing 147M29P01 to 1475M29P01) and the statement that the compliance period was revised to ensure no disks were omitted are internal document interactions: the amendment changes the content of an earlier AD text. This demonstrates that the AD interacts with its own prior versions through amendment to preserve coverage continuity and accuracy (Amendment note).

What the AD does not do in its text

• The AD does not reference specific Australian statutes, regulations, or administrative provisions beyond the issuing authority (CASA). It does not cite enabling legislation, enforcement regulations, or penalties. It does not provide explicit cross‑links to maintenance recordkeeping rules, certification of release to service requirements, or obligations vis‑à‑vis aircraft registration or continued airworthiness certification. Those interactions are likely governed by other instruments, but they are not recited in this AD.

Operational interaction consequences

• Because the AD requires compliance with CFMI SBs, operators must align internal maintenance procedures and recordkeeping with those manufacturer procedures to demonstrate compliance with the AD.
• The AD’s cross‑reference to a DGAC AD suggests there may be parallel or complementary requirements issued by other authorities; operators who operate internationally or who have parts subject to multiple directives should consult each applicable directive to reconcile obligations.

In sum, the AD interacts procedurally with manufacturer SBs and references another airworthiness directive, but it does not itself map onto or reproduce broader legislative enforcement or recordkeeping provisions within its text. Operators must therefore manage the interaction between this AD, the incorporated CFMI SBs and any referenced ADs outside the AD’s text.

This document is labelled AD/CFM56/9 Amdt 1 and carries an effective date of 6 July 2006 (title and Compliance). The signature block is dated 24 May 2006 and signed by James Coyne, identified as a delegate of the Civil Aviation Safety Authority (signature block). The AD text contains explicit self‑referencing amendment information.

Content of the amendment

• Corrected typographical error: The amendment corrects a typographical error in the part number listing for certain disks. The AD notes that the part number previously printed as 147M29P01 should have read 1475M29P01 (Amendment note). This correction is substantive to applicability because part number accuracy determines whether particular discs fall within the AD’s scope.

• Revised compliance period: The amendment states that the revised compliance period is intended to ensure that no discs have been omitted from the requirements of this AD due to the earlier typographical error (Amendment note). The AD therefore not only corrects a document error but also adjusts the compliance timing to maintain comprehensive coverage.

Referenced dates in the AD and SBs

• The AD incorporates CFMI Service Bulletins dated 14 January 1997 (CFM56‑2 SB No. 72‑817; CFM56‑3/‑3B/‑3C SB No. 72‑843) and 31 January 1997 (CFM56‑2A SB No. 72‑419 Revision 1; CFM56‑2B SB No. 72‑561 Revision 1) (Requirement). These SB dates are older than the AD amendment date and indicate the AD formalises a retrospective compliance requirement based on earlier manufacturer advice.

Relationship of the amendment to original AD

• The document is an amendment (Amdt 1) to AD/CFM56/9. The amendment corrects a misprint and ensures applicability is not unintentionally narrowed. The AD text indicates the amendment’s sole substantive corrections are the part number and the compliance period; it does not change the inspection method, the removal requirement, or the list of engine families.

Administrative chronology

• Signed 24 May 2006; amendment effective 6 July 2006; the AD requires inspections within 30 days after that effective date unless already accomplished (signature block; Compliance). The AD’s structure and wording imply an earlier AD/CFM56/9 existed with the typographical error; Amdt 1 replaces or corrects that earlier instrument.

What the amendment does not do

• The amendment does not add new part numbers beyond the corrected entry, does not change the list of engine variants subject to the AD, does not alter the required eddy current inspection method, and does not modify the mandated removal criterion. It corrects the textual accuracy of the component identification and clarifies the compliance timing to forestall omissions caused by the error.

For operators and maintainers, the amendment history means that they must ensure they reference the amended AD version and the corrected part number when determining whether their parts are affected.

The AD text contains no litigation history, no citations of judicial or administrative decisions, and no mention of disputes, appeals or legal proceedings. The instrument is a technical airworthiness directive with only implementation content, background factual statements, and a signature block; it does not record any litigation or adjudication associated with its issuance (entire AD text).

What the AD does provide instead of litigation entries

• A factual background: the AD explains the proximate cause for the directive , a crack found in a rim bolt hole during a routine shop eddy current inspection and an investigative finding that the crack initiated from a gouge caused by a drill break during manufacture (Background). The AD cites a DGAC AD (DGAC AD 97‑327(B)) but does not indicate whether that referral generated any dispute or litigation.

Implications of the absence of litigation information

• The absence of litigation material in the AD means that compliance practitioners cannot derive any case law, precedent, enforcement outcomes or contested interpretations from the text itself. There is no recorded contested ruling, variation or legal challenge included. The AD’s operational content stands alone in the document; any litigation history would need to be sought outside the AD in court records, tribunal decisions, or CASA administrative files , those materials are not part of this AD’s text.

Guidance for practitioners

• When advising clients or preparing compliance programmes, practitioners should note that this AD does not contain adjudicative history. If legal precedent or enforcement history is required to inform risk assessment (for example, past enforcement outcomes for AD non‑compliance), that material must be sought from external legal and regulatory records. The AD itself will not supply such litigation context.

In short, the AD contains no litigation history; it is a regulatory technical instrument that sets out a mandatory safety action and its factual basis, and it does not catalogue any subsequent or prior legal proceedings.

The AD’s concise text nonetheless contains several practical traps that may lead to inadvertent non‑compliance or operational disruption if overlooked.

Typographical correction risk

• The AD specifically corrects a prior typographical error in a part number (147M29P01 corrected to 1475M29P01). If operators or maintainers relied on the misprinted part number in earlier versions, some discs could have been omitted from inspection. Ensure the corrected part number is used in all queries and inventory checks; do not rely on earlier printed lists (Amendment note).

Serial number dependence

• Applicability is by part number and serial number as listed in Table 1 of the applicable CFMI Service Bulletin. The AD does not reproduce Table 1 in its text. Therefore, operators must consult the correct SB and the correct table for serial numbers; failure to consult the SB Table 1 may lead to missing affected discs (Requirement). Verify you are consulting the SB version that the AD calls up for your engine variant.

Engine‑variant specific SBs

• The AD references different SBs for different engine families, including specific revision and date numbers. Using the wrong SB (for example, applying the CFM56‑2 SB to a CFM56‑3 engine) risks incomplete compliance. The AD mandates compliance “in accordance with” the identified SB for each engine family, so ensure the SB variant matches the engine type in your fleet (Requirement).

Short compliance window

• The AD sets a 30‑day compliance window measured from the effective date (6 July 2006). Short windows compress maintenance schedules and may require deferment or prioritisation of planned work. If inspections are not already completed, operators must rapidly schedule eddy‑current testing; failure to meet the window could produce regulatory exposure even though the AD itself does not list penalties (Compliance).

Scope‑narrowing by part number precision

• The AD is narrowly focused on seven listed part numbers. If an operator has near‑equivalent parts with different part numbering conventions (for example, suffix differences, leading zeros, or variant marks), they must not assume equivalence; only the listed part numbers and the serial numbers in Table 1 are covered. Conversely, parts with alternate part numbers might still be covered by other directives or SBs; do not assume absence from this AD equals absence of risk.

Focus on bolt‑hole damage

• The AD background identifies a crack that initiated from a gouge in a rim bolt hole caused by a drill break during manufacture. The effect is that inspections should pay particular attention to bolt hole condition. However, the AD prescribes eddy‑current inspection per SB and does not itself expand scope to other potential defect locations; follow the SB instructions explicitly to ensure bolt holes and critical detail areas are inspected as required (Background; Requirement).

No repair instructions in AD

• The AD requires removal from service of cracked or gouged discs but does not specify repair options. If an operator finds a cracked or gouged disc, the AD does not provide an in‑text pathway for repair, disposition, return to service or parts replacement; this must be handled through normal maintenance procedures and any applicable SB or supplier instructions (Requirement).

Cross‑reference to DGAC AD

• The AD references DGAC AD 97‑327(B). If an operator relies on guidance or interpretations tied to that DGAC AD, they must verify applicability and content independently. The CASA AD does not restate the DGAC AD; it only notes the referral (Requirement, Note).

Documentation and recordkeeping

• The AD mandates inspection but does not specify a reporting format or the records that must be submitted to CASA. Ensure internal maintenance records capture the required identification, inspection results, serial numbers inspected, and any removal from service actions to demonstrate compliance if later queried by regulators or auditors.

Inventory and spares

• The AD’s reach includes spares and stock holdings of the listed part numbers and serial numbers. Parts managers must ensure these items are identified and inspected or segregated as necessary; overlooking inventory items may leave non‑airworthy parts available for fitment.

In short, small documentary details , part number precision, correct SB identification, serial number matching, the short compliance window, and bolt hole focus , are the key practical gotchas in this AD.

The AD prescribes a compact compliance path. The following stepwise checklist translates the AD’s text into operational steps operators and maintenance providers should follow to satisfy the directive.

1. Confirm applicability to your fleet

• Identify aircraft with CFMI CFM56‑2, ‑2A, ‑2B, ‑3, ‑3B or ‑3C engines.
• For each engine, identify whether the installed HPTR fan disc has a part number listed in the AD: 1475M29P01, 1475M29P02, 9514M69P01, 9514M69P04, 9514M69P05, 9514M69P06, 9514M69P09 (Applicability; Requirement).
• Verify serial numbers for each disc against Table 1 in the applicable CFMI Service Bulletin (the AD makes serial numbers in Table 1 decisive) (Requirement).

2. Obtain the correct Service Bulletin

• For each affected engine variant, obtain the CFMI SB specified in the AD and the correct revision/date:
  • CFM56‑2: SB No. 72‑817 dated 14 January 1997;
  • CFM56‑2A: SB No. 72‑419 Revision 1 dated 31 January 1997;
  • CFM56‑2B: SB No. 72‑561 Revision 1 dated 31 January 1997;
  • CFM56‑3/‑3B/‑3C: SB No. 72‑843 dated 14 January 1997 (Requirement).
• Confirm that the SB Table 1 used to identify serial numbers is that which the AD references.

3. Schedule and perform eddy‑current inspections

• Plan to perform eddy‑current inspections of all identified HPTR discs in accordance with the procedures and parameters set out in the applicable CFMI SB (Requirement).
• Complete inspections within 30 days after the AD’s effective date unless the inspection was already accomplished before that date (Compliance). The AD effective date is 6 July 2006 (Compliance).

4. Focus on bolt hole and rim areas

• The AD’s background highlights a crack initiated from a gouge in a rim bolt hole due to a manufacturing drill break; ensure the eddy‑current inspection per the SB covers bolt hole rim areas and any gouge‑prone features identified in the SB (Background; Requirement).

5. Disposition non‑conforming discs

• Any HPTR disc found to be cracked or gouged during inspection must be removed from service (Requirement). Document the removal, segregate the part, and follow your organisation’s procedures for replacement and for traceability of removed parts.

6. Recordkeeping and proof of compliance

• Record serial numbers inspected, the inspection date, the SB used (including revision/date), the inspection results and any removal actions taken. Although the AD does not set a specific reporting form, maintain these records to demonstrate compliance if required by CASA or for internal audit.

7. Verify part number correction

• Ensure the corrected part number 1475M29P01 is used in all parts queries and records; do not rely on the earlier misprint 147M29P01 (Amendment note). Reconcile inventory and maintenance records against the corrected part number to avoid omissions.

8. Consider cross‑referenced directives

• The AD notes DGAC AD 97‑327(B) “refers.” Consult that DGAC AD if relevant to your parts, operations or international oversight arrangements to ensure any overlapping requirements are met (Requirement, Note).

9. Communicate with stakeholders

• Notify relevant maintenance providers, logistic personnel, parts managers and airworthiness staff of the need to inspect and, if necessary, remove affected discs. Coordinate with heavy‑maintenance shops to meet the 30‑day window and to ensure the SB procedure is understood and applied.

10. Plan for parts replacement and serviceability

• Anticipate supply chain and lead time issues for replacement HPTR discs if removals from service occur. The AD requires removal but does not provide in‑text replacement or repair routes; plan replacement procurement and installation under normal continuing airworthiness procedures.

Notes and cautions

• Do not substitute another inspection method or deviate from the SB procedure without an authorised alternative method of compliance; the AD itself prescribes the SBs as the means of compliance (Requirement). The AD does not state an AMOC process within its text.
• The AD provides no explicit reporting or notification form to CASA. Maintain clear internal documentation to enable prompt response to regulatory queries.

By following these steps , identify, obtain SB, inspect per SB within 30 days, remove any cracked or gouged discs, and document actions , an operator or maintainer will have performed the actions the AD requires in its text.