AD/S-PUMA/57 Amdt 1 - Tail Servo-Control

The directive centres on three technical and regulatory concepts: (1) mechanical integrity of the tail servo-control assembly, specifically axial play of control levers on distributor shafts; (2) inspection and torque verification as corrective and preventive measures; and (3) time-limited compliance windows keyed to time-in-service or flying hours and to whether components are installed or held as spares.

Mechanical integrity: The immediate safety concern arises from a reported event where, after removal for repair, a control lever slipped along a distributor shaft and could have totally separated from that shaft, producing tail servo-control failure (Background). The directive therefore targets axial play of the two levers along the distributor shafts as the proximate hazard. The required manual check for absence of axial play is the primary diagnostic measure (Requirement, paragraph references to Eurocopter AS332 ASB 67.00.31.2/31.3/31.4/31.5).

Inspection and torque verification: The amendment retains the previously mandated one-time manual inspection and adds a tightening torque check and follow-up inspections. The torque check applies initially to servo-controls that have exceeded a specified cumulative time in service threshold of 535 hours at the effective date (Requirement). The ASB paragraphs identified in the Directive are the normative procedure references for how to perform those manual checks and torque checks. The Directive also requires torque checks on spare units prior to installation (Requirement).

Temporal and scope distinctions: The instrument differentiates between units already installed and spares, and between units above or below the 535 hours TIS threshold. Compliance windows are expressed in both TIS and flying hours: immediate short windows (for example within 15 hours TIS for units above 535 TIS), absolute TIS cut-off points (no later than 550 hours TIS for units under 535), and follow-up windows (135-165 flying hours after the relevant initial check). There is also a distinct requirement that if axial play is detected, replacement must occur prior to further flight (Compliance items 3, 4, 5). The Directive therefore imposes a mix of diagnostic, corrective and timing obligations tied to service life and operational metrics.

Regulatory cross-reference: The Directive explicitly refers to the French DGAC AD F-2005-137 and notes EASA approval No. 2005-6119 dated 27 July 2005. It also states that it supersedes an earlier instrument (UF-2004-197). These cross-references show the Directive is not standalone but built on prior foreign regulator action and European approval, and that it replaces previous domestic direction (Note and Background).

Operational consequence: Mechanically, the Directive mandates replacement of non-compliant servo-controls before further flight, creating a hard operational boundary: flights cannot legally continue with known axial play. For spares, checks must be completed before fitment, creating a barrier to using inventory without prior verification (Requirement; Compliance).

The Applicability clause identifies the directly affected parties: operators and maintainers of Eurocopter AS 332 L, L1, C, C1 and AS 332 L2 helicopters that are fitted with tail servo-controls P/N SC7251 before amendment J or P/N SC7270 before amendment F. That definition focuses effect on individual airframes whose fitted servo-controls match the listed part numbers and amendment status.

Operators: Aircraft operators that possess any of the listed AS 332 variants and that have the specified tail servo-controls installed are required to perform the inspections and checks and to replace any servo-control that fails the inspection prior to further flight. Operators therefore bear the operational impact of scheduling checks, grounding aircraft where required, arranging repairs or replacements, and managing compliance within the prescribed TIS and flying-hour windows (Requirement; Compliance).

Maintenance organisations and engineers: The technical tasks specified , manual checks for axial play, tightening torque checks, and replacements , fall to maintenance organisations and qualified maintenance personnel who must apply the procedures set out in the Eurocopter ASBs referenced by the Directive (Requirement). The ASB paragraph references (2.B.2, 2.B.3, etc.) indicate that specific procedures and torque values are contained in the manufacturer’s service information, which maintainers must follow.

Parts suppliers and stock managers: The Directive imposes an obligation on those holding spare tail servo-controls: spares must have the tightening torque check completed before installation after the effective date (Requirement). This affects inventory management, because spares that have not undergone the specified checks cannot legally be installed without first being requalified according to the Directive. Suppliers of parts will see demand for compliant units and potential returns or servicing of existing spares.

Regulator and certification bodies: The instrument is issued by the Civil Aviation Safety Authority, as evidenced by the signature of its delegate, James Coyne (2 September 2005). The directive also references actions by the French DGAC and an EASA approval number, indicating that the Australian regulator is adopting or aligning with foreign regulator findings or approvals. Those regulators are affected in terms of coordination and cross-reference (Note).

Flight crews and commercial operators: While the technical tasks fall to maintenance personnel, flight crews and operators will be affected operationally because detection of axial play requires replacement before further flight. The compliance windows measured in flying hours create scheduling constraints , flights may need to be cancelled or aircraft rotated to ensure adherence to the time windows (Compliance).

Insurance, leasing and asset managers: Although the Directive does not refer to commercial contracts, operators who lease AS 332 helicopters or who insure them will be affected indirectly by any grounding, maintenance costs, or parts replacement obligations. Parties responsible for continuing airworthiness under leasing arrangements will need to ensure compliance with the specified actions and timing.

Regulatory delegates and authorised persons: The instrument is signed by a CASA delegate. Parties interacting with CASA for clarification, approvals for method of compliance, or record acceptance will be dealing with CASA delegates or nominated approval authorities, though the Directive itself does not set out an approval process beyond mandating the ASB procedures.

Duties

• Perform a one-time manual check for absence of axial play of the two levers along the distributor shafts of the tail servo-control in accordance with the instructions described in paragraph 2.B.3 of Eurocopter AS332 ASB 67.00.31.2. This is mandated for applicable installed units (Requirement 1).

• For servo-controls that have accumulated more than 535 hours TIS since new at the effective date of the Directive, carry out the tightening torque check detailed in paragraph 2.B.2 of Eurocopter AS332 ASB 67.00.31.3, and perform the manual axial-play check in accordance with paragraph 2.B.3 of ASB 67.00.31.4 (Requirement 1).

• Replace the servo-control before resuming flights if axial play is found, as specified in paragraph 2.B.3 of ASB 67.00.31.5 (Requirement 1).

• For tail servo-controls held as spares, carry out the tightening torque check detailed in paragraph 2.B.2 of ASB 67.00.31 before they are installed (Requirement 1).

• Meet specific timing windows: for installed servo-controls with more than 535 hours TIS at the effective date of the original directive, conduct the torque check within 15 hours TIS after the original directive effective date; for installed servo-controls with less than 535 hours TIS, complete checks no later than 550 hours TIS since new. There are additional deadlines: “no later than within the 110 flying hours as from the effective date of this AD” for another item, and follow-up inspections/checks within 135-165 flying hours after the initial check (Compliance section).

• Do not install a spare unit without first completing the torque check; do not resume flights with a unit that fails the axial-play check until it has been replaced (Compliance items 4 and 5; Requirement).

Rights and implicit administrative matters

• The Directive does not set out express administrative appeal rights or approval pathways within its text. It references Eurocopter ASBs for procedural detail, so maintainers have the right to rely on the specified ASB procedures as the method of compliance. The ASB paragraphs cited provide the technical instructions that the Directive mandates be followed (Requirement).

• The Directive cross-references DGAC AD F-2005-137 and indicates EASA approval, which suggests that operators may consult those documents alongside the ASBs for additional or harmonised instruction. The Directive supersedes a prior instrument (UF-2004-197), and operators are obliged to comply with the current directive rather than the superseded one (Note; Background).

• The Directive creates an operational right of action to replace defective components: if axial play is found, the operator must remove and replace the servo-control before further flight. That is a mandatory remedial right the regulator has imposed to restore airworthiness.

Observable enforcement implications

• The Directive requires preventive and corrective maintenance actions within specified intervals. Although specific penalties or enforcement mechanisms are not spelled out in this text, the obligations create negative operational consequences for non-compliance: aircraft cannot continue to be flown if a detected axial play condition exists; spare components cannot be fitted without prior checks (Compliance items 3-5; Requirement).

• The manufacture’s ASBs are incorporated by reference as the technical standard. The right to use other methods of compliance or alternative procedures is not addressed in the text of this Directive; therefore, compliance with the exact ASB paragraphs cited is the mandated route within this instrument.

The directive text supplied does not specify monetary penalties, administrative sanction types, or the enforcement mechanism in statutory language. There is no express penalty schedule or reference to criminal or civil penalties contained in the document. The instrument does, however, impose mandatory operational requirements that, if not met, have immediate practical consequences for flight operations.

Enforcement by operational consequence: The Directive requires replacement of a servo-control before resuming flights if axial play is found (Requirement; Compliance item 4). That requirement creates an operational compliance boundary: detection of axial play requires remedial action prior to further flight. By its terms, airworthiness is restored only after replacement as specified in the manufacturer’s ASB. The practical effect is that non-compliance can, at minimum, result in grounding or withdrawal of the aircraft from service until the corrective action is performed.

Regulatory issuer and implied enforcement authority: The Directive is issued under the authority of the Civil Aviation Safety Authority, as shown by the signature block naming James Coyne, Delegate of CASA, dated 2 September 2005. While the Directive does not spell out sanctions, CASA, as the issuing regulator, would be the body through which regulatory compliance is monitored and enforced; the text itself does not describe CASA’s enforcement procedures or penalties.

References to other regulatory instruments: The Directive references DGAC AD F-2005-137 and EASA approval No. 2005-6119. Those referenced instruments may themselves carry enforcement consequences in their jurisdictions, but this Directive does not recite enforcement actions under those instruments or specify cross-border enforcement mechanisms. The Directive also supersedes UF-2004-197, indicating that compliance must follow the current Directive rather than the superseded instrument.

Record-keeping and proof of compliance: The Directive prescribes actions and timing windows but does not, in the supplied text, stipulate record-keeping requirements or documentary proof of completion. That absence means the Directive itself does not indicate how an operator should demonstrate compliance to the regulator. In practice, airworthiness oversight typically requires records, but such procedural or evidentiary requirements are not included in this document.

Summary: The instrument imposes mandatory technical and timing obligations and specifies conditions under which flight may not be resumed, but it does not on its face set out formal penalties or the administrative enforcement process. Enforcement implications are visible through imposed operational constraints and the regulator’s authorship, rather than through an express penalty regime within the text.

The Directive explicitly cross-references and aligns with foreign and European regulatory actions and replaces an earlier domestic directive. These cross-references are the primary textual evidence of legal interaction in the supplied material.

Cross-reference to DGAC and EASA: The instrument states “Note: DGAC AD F-2005-137 EASA approval No. 2005-6119 dated 27 July 2005 refers.” That shows the Directive is related to, and in part dependent upon, a French Direction Générale de l’Aviation Civile airworthiness directive and an EASA approval. The reference indicates regulatory coordination or harmonisation: Australian action is being taken in light of findings or approvals from foreign and regional regulators. The Directive does not set out the legal mechanism by which those foreign instruments are adopted domestically; the text simply references them as related authorities.

Superseding prior directive: The Directive states that it supersedes UF-2004-197 (Requirement and Background). That creates a temporal legal relationship: obligations under the current Directive replace those of UF-2004-197. Operators and maintainers must follow the present Directive’s requirements rather than the superseded one. The Directive also notes that the original issue became effective on 7 January 2005 and that this amendment becomes effective on 10 September 2005. Those dates create a timeline for the interaction between successive directives.

Incorporation of manufacturer service information: The Directive requires actions to be performed “in accordance with” specified paragraphs of Eurocopter AS332 ASBs (Requirement). This creates an interaction between regulatory mandates and manufacturer technical documentation. The ASBs are incorporated into the compliance obligation by reference to specific paragraphs (for example 2.B.2, 2.B.3, etc.). The Directive therefore interacts with contractual and technical regimes: maintainers must implement the manufacturer’s procedures to meet the regulator’s directive.

Operational compliance versus statutory enforcement: The Directive sets technical duties and timing windows but does not itself lay out enforcement mechanisms or penalties in the text provided. Interaction with the broader aviation safety legal framework is therefore implicit: operators will need to reconcile the Directive with other statutory obligations under the Civil Aviation safety regime (for example continuing airworthiness requirements), but those statutory obligations and enforcement powers are not detailed in this document.

International harmonisation and approvals: The EASA approval reference suggests the Directive is part of a broader international airworthiness process in which manufacturer service bulletins and national ADs are reviewed or approved by a regional authority. That regional approval is recorded in the Directive’s note, showing an interaction between domestic regulatory action and regional certification processes.

Practical implication for contractual regimes: Although the Directive does not mention leasing, warranty or supplier obligations, the requirement to perform checks on spares and to replace units that fail the checks will interact in practice with parts supply contracts, maintenance agreements, and continuing airworthiness responsibilities under aviation law. Those interactions are not detailed in the text, but the content of this Directive will need to be accommodated within those contractual and regulatory frameworks.

The supplied text records a discrete amendment history and supersession relationships within a short timeframe. The instrument on its face sets out the following history items:

• Original issue effective date: The Background notes that “The original issue of this Directive became effective on 7 January 2005.” That establishes the first iteration of the Directive and its effective date.

• Superseded instrument: The Directive states that it “supersedes UF-2004-197.” This identifies the immediately prior instrument that the present directive replaces, establishing the chain of directive versions operators must follow.

• DGAC and EASA references: The Note references DGAC AD F-2005-137 and EASA approval No. 2005-6119 dated 27 July 2005. That indicates that subsequent to the original issue, related foreign regulatory actions and regional approvals were recorded and incorporated into the amendment.

• This amendment’s effective date: The text explicitly says, “This Amendment becomes effective on 10 September 2005.” The signature block carries a date of 2 September 2005, indicating the delegate signed the amendment on that date and set an effective date eight days later.

• Content evolution: The Background describes how the amendment changes the original issue: “The original issue of this Directive required a one time manual inspection to ensure the integrity of the servo-control assembly. This amendment maintains the one time inspections, introduces follow up inspections and torque checks, and includes actions to be performed if tail servo-controls fail those checks detailed in this Directive.” That sentence supplies a succinct statement of the substantive change introduced by the amendment relative to the original AD.

• Referenced ASBs and procedural paragraphs: The Requirement and Compliance sections reference multiple ASB paragraphs (for example 2.B.2; 2.B.3; 2.B.4; 2.B.5 of the Eurocopter AS332 ASBs 67.00.31.x series). Although the directive text does not list revisions of those ASBs, the amendment’s practical effect is to incorporate additional procedural steps (torque checks and follow-ups) as set out in those ASB paragraphs.

• Inclusion of spare part requirements: The amendment explicitly adds a duty for tail servo-controls held as spares to undergo the tightening torque check before installation, an item that was not part of the original one-time inspection-only requirement. That change affects spares management practices post-amendment.

Taken together, these entries provide the immediate amendment history relevant to this directive: an original AD that mandated a one-time inspection, an identified safety event prompting further action, related foreign approvals, and an amendment (effective 10 September 2005) that preserved the original inspection while adding torque checks and follow-up inspections and adding spare-part verification requirements.

The supplied instrument contains no litigation history, citations to court decisions, or any mention of proceedings, appeals, or disputes. There are no judicial or administrative decisions recorded in the text that interpret, challenge, or affirm this Directive. The document’s Background, Requirement, Compliance, Note and signature elements do not reference any litigation or pending legal disputes.

Because no litigation is recorded in the source, the only available observations that can be grounded in the document are these:

• The Directive is issued by a regulatory authority (CASA delegate) and is framed as a compliance instrument that supersedes a prior directive (UF-2004-197). The text does not include appeal mechanisms, enforcement provisions, or adjudicative pathways; nor does it indicate any ongoing or previous legal challenges to the content or force of the directive.

• The Directive references a safety occurrence (a report following removal for repair that a control lever had slipped along the shaft; investigation revealed potential total separation), and it records the regulatory response in the form of a mandatory directive requiring inspections, torque checks and replacement where necessary. The text does not state whether the incident that prompted the Directive gave rise to litigation or claims against manufacturers, maintenance organisations, or operators.

• The Directive also references foreign regulator action and regional approval (DGAC AD F-2005-137; EASA approval No. 2005-6119). The document does not mention any legal disputes involving those referenced instruments.

Users requiring litigation or case law that addresses enforcement, interpretation, or challenges to this AD should note that the present text does not supply any such material. Any search for litigation outcomes, administrative reviews, or court challenges would need to consult external legal databases, regulatory records, or tribunal decisions, none of which are contained in the supplied document.

The directive text contains specific technical, temporal and interpretive details that create several practical pitfalls for operators and maintainers. The following items are drawn directly from the document and highlight areas where mistakes or misunderstandings are likely.

Part-number and amendment-status specificity: Applicability is limited to helicopters fitted with tail servo-controls P/N SC7251 before amendment J or P/N SC7270 before amendment F. That language requires attention to both part number and the internal amendment or revision status of the part. Operators who track components by part number only may overlook the “before amendment” qualifying language. Misidentifying the amendment status of a servo-control could lead to non-applicability being mistaken for applicability, or vice versa.

Multiple overlapping compliance metrics: The Directive uses both “time in service since new” (TIS) thresholds and flying hours counted from an effective date. For example, an installed servo-control that had accumulated more than 535 hours TIS at the effective date of the original Directive must have a torque check within 15 hours TIS; those with less than 535 hours must be checked no later than 550 hours TIS since new. Separately, another item requires action “no later than within the 110 flying hours as from the effective date of this AD,” and follow-up inspections are required “within a period of 135 to 165 flying hours following” the earlier checks. Operators must carefully track both cumulative TIS and flying hours since effective dates to ensure compliance. Confusing these metrics or applying the wrong window is a likely operational error.

Reference to manufacturer ASB paragraphs: The procedures required by the Directive are given by reference to specific paragraphs of Eurocopter AS332 ASBs (for example 2.B.2; 2.B.3; 2.B.4; 2.B.5). The Directive does not reproduce the technical steps or torque values; it mandates following those ASB paragraphs. Maintenance staff who do not have the correct ASB documents or who misapply the paragraph references may not perform the mandated procedures correctly. Access to the correct ASB revision that corresponds to the paragraph citations is therefore critical.

Spare management trap: The Directive requires that tail servo-controls held as spares undergo the tightening torque check detailed in the ASB before installation. This requirement means that spares in inventory may not be immediately serviceable without prior verification. Operators who assume that spares can be fitted at short notice risk non-compliance if those spares have not been checked in accordance with the Directive.

Replacement before flight: If axial play is found on inspection, the Directive requires replacement before resuming flights. That creates an immediate operational constraint: aircraft with a failed servo-control condition cannot legally continue flight operations until the mandated replacement is effected. Operators must plan for potential grounding and parts availability in their compliance planning.

Ambiguity on record-keeping and alternative compliance: The Directive does not specify record-keeping requirements or whether alternative methods of compliance or equivalent procedures may be approved. Without explicit text, operators should not assume there is flexibility beyond the ASB procedures cited. Failure to document compliance to regulator expectations, even where physical actions were taken, could create later compliance disputes.

Timing alignment between original and amended directives: The Compliance section references the “effective date of the original issue of this Directive” for certain windows (for example the 15-hour TIS window for >535 hours units). Operators must be precise about which effective date applies to each compliance window,some deadlines are measured from the original issue, others from the amendment effective date. Misaligning these dates will create incorrect compliance calculations.

Lack of penalties or enforcement detail in the text: The absence of explicit enforcement provisions in the document is itself a gotcha. Operators may be uncertain about the consequences of late compliance or may expect the directive to include administrative appeal or rectification procedures. Because the directive text is silent on these procedural matters, operators should presume the obligations are binding and seek clarification from CASA where needed.

The Directive prescribes a sequence of technical actions, timing constraints and replacement rules. The following compliance checklist follows directly from the Requirement and Compliance sections and from the ASB paragraph references in the Directive. It is framed as a practical operational sequence that implements the instrument’s mandatory steps.

1. Identify affected aircraft and components: For each AS 332 L, L1, C, C1 or L2 helicopter in the fleet, determine whether the tail servo-control installed is P/N SC7251 before amendment J or P/N SC7270 before amendment F (Applicability). Confirm the amendment/revision status of the part to establish applicability.

2. Determine TIS and effective-date windows: For each affected servo-control, determine cumulative hours time in service (TIS) since new as of the effective date of the original Directive (7 January 2005) and calculate flying hours since the effective date of this AD where relevant. This will establish whether the servo-control is above or below the 535 TIS threshold and which compliance windows apply (Compliance).

3. Obtain the referenced ASBs: Secure the Eurocopter AS332 Alert Service Bulletins specified in the Directive and identify the exact paragraphs cited: 2.B.2 for tightening torque checks, 2.B.3 for the manual axial-play check, and 2.B.4 and 2.B.5 where referenced for further detail. The Directive requires procedure execution “in accordance with” these ASB paragraphs (Requirement). Do not attempt to reconstruct torque values or step sequences from memory; follow the ASB text.

4. Perform initial checks within the specified windows:

   • For servo-controls with more than 535 hours TIS at the original effective date, carry out the tightening torque check (ASB 2.B.2) and the manual axial-play check (ASB 2.B.3) within 15 hours TIS after the original effective date.
   • For servo-controls with less than 535 hours TIS, perform the checks no later than when the servo-control reaches 550 hours TIS since new.
   • Complete any other item required “no later than within the 110 flying hours as from the effective date of this AD” within that 110 flying-hour window (Compliance).

5. Apply corrective action if axial play is detected: If the manual check reveals axial play, replace the servo-control before resuming flights, following the replacement procedure cited in paragraph 2.B.3 of the ASB and any associated instructions. Do not return the helicopter to service until replacement is completed (Requirement; Compliance item 4).

6. Follow-up inspections: After completing the initial checks, schedule and complete the follow-up inspections or torque verifications within 135 to 165 flying hours following the earlier checks as specified:

   • For units with more than 535 hours TIS at the effective date, complete the follow-up inspection 135-165 flying hours after the check in Requirement 2.
   • For units with less than 535 hours TIS at the effective date, complete the follow-up 135-165 flying hours after the torque check specified in Requirement 2 (Compliance item 3).

7. Check spares before installation: For tail servo-controls held as spares, perform the tightening torque check (ASB paragraph 2.B.2) before installing the spare in an aircraft after the effective date of the Directive. Do not install spares that have not undergone this check (Requirement; Compliance item 5).

8. Maintain operational planning for downtime: Because the Directive requires replacement before further flight if axial play is found, plan for potential aircraft grounding and parts procurement. Ensure access to replacement servo-controls that conform to the part-number amendment requirements or obtain appropriately amended/inspected units as necessary.

9. Seek clarification from regulator where necessary: The Directive references manufacturer ASB paragraphs and cross-references foreign regulatory action. If there is ambiguity about interpretation, timing calculations, or permissible methods of compliance, consult CASA (the issuer of the Directive) for clarification. The Directive itself does not include alternative methods of compliance or recordkeeping instructions, so regulatory guidance should be sought where operators need an approved alternative or confirmation of acceptable evidence.

10. Document actions in maintenance records consistent with normal continuing airworthiness practice: While the Directive does not specify recordkeeping requirements within the supplied text, the required technical actions and the timing windows mean operators will need contemporaneous maintenance records to establish when checks and replacements were completed and to prove compliance if asked by the regulator. Use the ASB references and the Directive’s compliance windows as the basis for entries in the aircraft’s maintenance log.

11. Coordinate with parts suppliers: Where spares are involved, ensure suppliers can attest to prior torque checks where applicable, or arrange for torque checks to be performed prior to installation. Given the spares-check requirement, inventorymarked “serviceable” prior to the Directive may not be serviceable without rechecking.

12. Replace or upgrade uncontrolled parts: If servo-controls are found to be non-compliant and replacements are fitted, confirm that replacement parts do not meet the “before amendment” exclusion (i.e., fit updated servo-controls where possible) to avoid future applicability. The Directive does not prescribe acceptable replacement part amendment status; ensure replacements are in serviceable and compliant form.

By following the steps set out above and executing the ASB-referenced procedures within the specified windows, operators and maintenance organisations implement the mandatory measures the Directive prescribes. The Directive itself specifies the ASB paragraphs and the compliance timing; adherence to those references is the required route to compliance.