AD/PA-46/32 Amdt 1 - Control Wheel Attachment

The directive rests on a small number of interlocking technical and regulatory concepts drawn explicitly from its text.

• Unsafe condition and causal mechanism. The Background states the FAA investigation found a control wheel attachment screw had unscrewed from its nut plate so the control wheel spun freely, and the screw was too short and the nut plate lacked proper locking characteristics. The AD therefore targets fastening integrity at the interface between the control wheel and the control column (Background).

• Two-tier remedial approach. The mandated remedy is split into two discrete tasks tied to the manufacturer’s Service Bulletin No. 1139A: Part I focuses on inspection and, where necessary, replacement of the screw and/or nut plate and requires installation of the attachment screw with Loctite thread‑locking compound; Part II mandates installation of a retainer clip, part number 104687‑002 (Requirement 1(a)-(c); Requirement 2). The text ties the mandatory steps explicitly to the service bulletin parts (Requirement).

• Applicability and selective application. Applicability is expressed in two groups with specific model and serial number ranges. Group A covers certain serial ranges of PA‑46‑350P Mirage and PA‑46‑500TP Meridian aircraft; Group B covers later serial ranges. Part I is required for Group A aircraft except those already modified per SB No. 1139 dated 28 August 2003; Part II applies to both Group A and Group B (Applicability; Requirement 1 & 2).

• Compliance measured in flight hours. The AD sets short, time‑in‑service compliance windows: one action within 25 hours time in service after 11 August 2004 and the other within 100 hours time in service after 11 August 2004, and it states those compliance times remain unchanged (Compliance).

• Cross‑reference to other instruments. The AD explicitly cross‑refers to a corrected FAA Airworthiness Directive (FAA AD 2004‑14‑12 Amdt 39‑13721) and to New Piper Service Bulletins (SB No. 1139 dated 28 August 2003 and SB No. 1139A dated 9 April 2004). The amendment corrects the internal reference to the service bulletin to SB No. 1139A (Background; Note).

• Outcome required before further flight. Where inspections reveal nonconformance (insufficient thread engagement or inadequate nut plate locking), the AD orders replacement "before further flight," imposing an operational grounding until the defect is rectified on affected aircraft (Requirement 1(a)-(b)).

These core elements show the instrument’s mechanics: it identifies a fastening failure mode, mandates inspection criteria, orders replacement when thresholds are not met, prescribes a thread‑locking compound on reassembly, and requires addition of a retainer clip design feature for broader mitigation, all within short operational timeframes.

The directive identifies affected aircraft by model and serial number ranges split into Group A and Group B. The table in the applicability states:

• Group A aircraft:

  • PA‑46‑350P Mirage, serial numbers 4636132 through 4636344
  • PA‑46‑500TP Meridian, serial numbers 4697001 through 4697162

• Group B aircraft:

  • PA‑46‑350P Mirage, serial numbers 4636345 through 4636348
  • PA‑46‑500TP Meridian, serial numbers 4697163 through 4697174

These serial‑range lists identify the set of aircraft the AD directly regulates (Applicability). The practical effect of that mapping is that owners, operators, maintenance organisations and certificated aircraft maintenance engineers (AMEs) responsible for the specified serial numbers have mandated actions under the AD.

The directive further differentiates within those affected parties:

• Operators of Group A aircraft that have not already been modified in accordance with New Piper Service Bulletin No. 1139 dated 28 August 2003 must perform the Part I inspection and remedial actions. The AD explicitly exempts Group A aircraft that already carry the earlier SB No. 1139 modification from Part I, creating a records‑based entitlement to avoid duplication of work (Requirement 1, first clause).

• All operators of the Group A and Group B aircraft listed must install the retainer clip p/n 104687‑002 in accordance with Part II of SB No. 1139A dated 9 April 2004 (Requirement 2). Thus the retainer clip requirement applies to a wider set of owners/operators.

Who pays: the source does not set out cost allocation or funding; by the structure of the AD the immediate economic obligation to arrange the inspections, any part replacements (screw, nut plate), procurement of the retainer clip (part number specified), the Loctite thread‑locking compound and labour falls to the operator/owner of the affected aircraft who must comply “before further flight” where defects are found and within the specified hours for the mandated actions (Requirement; Compliance). The instrument does not specify subsidies, reimbursements or government cost contributions.

Who decides: the directive is issued by the Civil Aviation Safety Authority and signed by a delegate, David Punshon, indicating the regulator has made the determination and established the compliance requirements and timeframes (David Punshon, Delegate of the Civil Aviation Safety Authority). Maintenance decisions on how to comply must follow Part I and Part II of New Piper SB No. 1139A dated 9 April 2004, which the AD expressly references as the procedural source for the required work (Requirement).

Affected service providers: certificated maintenance organisations and AMEs will be the parties to perform the inspections and fitting work; operators will need to maintain and present records that show whether a Group A aircraft has previously received SB No. 1139 dated 28 August 2003 to determine whether Part I applies (Requirement 1 exception).

The directive creates discrete duties for operators and maintenance providers of the listed aircraft. The instrument itself defines the duties by requirement and timing; it does not create express rights for third parties.

Explicit duties contained in the text:

• Inspection of control wheel attachment screw thread engagement. For applicable Group A aircraft (excluding those already modified to SB No. 1139 dated 28 August 2003), the operator must inspect the control wheel attachment screw for proper thread engagement, using the threshold provided in the AD: a minimum of one thread showing past the end of the nut plate. If inspection finds insufficient thread engagement, the screw must be replaced before further flight (Requirement 1(a)). The duty is both diagnostic (inspect) and corrective (replace if insufficient).

• Inspection of nut plate locking characteristics. The operator must inspect the nut plate for sufficient locking characteristics; the AD supplies a pass/fail metric: "If the screw can be fully inserted into the nut plate by hand (one thread showing past end of nut), then replacement of the nut plate is required before further flight" (Requirement 1(b)). This imposes a specific physical test and a replacement duty if the nut plate fails that test.

• Reassembly with thread‑locking compound. After inspection and any replacement, the operator must reassemble the control wheel and install the attachment screw using Loctite thread‑locking compound in accordance with Part I of SB No. 1139A (Requirement 1(c)). This creates a duty to use a specified fastening practice on reassembly.

• Mandatory installation of retainer clip part number 104687‑002. For both Group A and Group B aircraft in the applicability, the AD requires installation of the retainer clip p/n 104687‑002 in accordance with Part II of SB No. 1139A (Requirement 2). The duty encompasses procurement of the specified part and performing the installation to the manufacturer’s part II procedure.

• Timing duties. The AD prescribes time windows for compliance measured in hours time in service after 11 August 2004: one action within 25 hours and the other within 100 hours (Compliance). The text states these compliance times remain unchanged by the amendment, meaning operators are bound by the stated post‑11 August 2004 time windows.

Operational constraints arising from duties:

• "Before further flight" language. Replacement of screw or nut plate is required "before further flight" when defects are found (Requirement 1(a)-(b)). The duty therefore triggers an operational grounding for the affected aircraft until rectification is completed.

Rights or entitlements inferred from the text:

• Records‑based exception. The AD grants an exemption from Part I to Group A aircraft that are already modified per SB No. 1139 dated 28 August 2003. That exemption functions as a right to avoid repeating the Part I measures, contingent on the aircraft having been modified to that SB , a records and configuration entitlement reflected in the AD text (Requirement 1, opening clause).

• Procedural reliance on the service bulletin. The AD delegates the technical method for complying to the manufacturer’s SB No. 1139A (both Part I and Part II). Operators therefore have a defined path to compliance by following the SB parts cited (Requirement 1 & 2).

What the AD does not specify:

• The directive does not set out administrative appeals, mitigation, or alternative methods of compliance within the text provided. It does not specify acceptable substitutions for Loctite or alternative hardware beyond the specified part number, nor does it provide cost recovery or subsidy mechanisms. The AD also notes a cross‑reference to a corrected FAA AD and the manufacturer's SBs, but does not itself contain testing protocols beyond the pass/fail descriptions quoted (Requirement; Note; Background).

The text of the amendment supplies no detailed enforcement provisions, penalty schedules or explicit sanctioning language. The instrument carries typical formal indicia of a regulator's mandatory directive: it is issued by the Civil Aviation Safety Authority and signed by a delegate, and it sets mandatory actions and compliance timeframes for the specified aircraft (This Amendment becomes effective on 17 March 2005; David Punshon, Delegate of the Civil Aviation Safety Authority). Beyond that formal issuance, the document contains no section within its text that prescribes fines, licence suspensions, defect reporting penalties, or civil enforcement steps.

What is explicit:

• Mandatory corrective actions. The AD’s requirements are mandatory for the identified aircraft and contain clear deadlines measured in hours time in service and "before further flight" constraints where defects are found (Requirement; Compliance). The directive therefore establishes operational obligations likely to be enforced by the regulator, but the AD itself does not state the enforcement mechanism in this text.

What the instrument omits (and should be checked by operators):

• The AD does not state in its text whether failure to comply constitutes an offence under a particular statutory provision, or what penalties might follow from non‑compliance. It also does not specify whether CASA will issue notices to show cause, grounding orders, or accept alternative methods of compliance. The AD likewise does not describe any requirement to notify CASA after compliance or how compliance is to be recorded administratively.

Practical consequences for affected parties arising from these omissions:

• Because the AD mandates corrective work and timing but does not describe enforcement steps in the instrument, operators must assume the directive is binding and will be enforced through the regulator’s standard aviation safety enforcement framework, and should therefore proactively confirm reporting and recordkeeping expectations with CASA. The AD’s issuance by a CASA delegate and the "before further flight" replacement requirement make it prudent for owners and maintenance providers to document compliance actions and retain evidence of parts procurement and serial numbers of fitted parts, even though the AD text itself does not prescribe the post‑compliance administrative steps (Requirement; Compliance; This Amendment becomes effective on 17 March 2005).

• The AD does reference corrected FAA AD 2004‑14‑12 Amdt 39‑13721 and New Piper Service Bulletin No. 1139A, which contain procedural details that are necessary to execute the AD’s requirements; enforcement may depend on adherence to those referenced documents (Note).

Within the text provided, the amendment establishes its regulatory effect principally by cross‑reference to two external technical instruments and to the FAA corrective action. The document itself does not purport to restate or override broader aviation safety legislation; rather it operates as an airworthiness directive referencing manufacturer guidance and a related FAA AD.

Explicit cross‑references in the text:

• Manufacturer’s Service Bulletins. The AD requires procedural compliance "in accordance with Part I of SB No. 1139A dated 9 April 2004" for the inspection/repair and "Part II of SB No. 1139A dated 9 April 2004" for the retainer clip installation (Requirement 1 & 2). That means the legal force of the AD integrates the manufacturer’s SB as the method of performance; compliance requires following the SB instructions cited.

• FAA AD cross‑reference. The AD contains a Note that reads: "Corrected FAA AD 2004‑14‑12 Amdt 39‑13721 refers." The Background explains Amendment 1 was issued in response to the issue of a corrected copy of the related FAA AD, and that the only change required in this Directive was a textual correction to the service bulletin reference (Background; Note). This explicitly links the CASA AD to the FAA’s regulatory work on the same technical issue and indicates the CASA instrument implements substantially the same safety response tailored to the aircraft serial ranges listed.

Interactions to be inferred from the instrument’s structure:

• Incorporation by reference of manufacturer procedures. By directing operators to perform actions "in accordance with" specific parts of the service bulletin, the AD effectively makes those parts the required method to meet the regulator’s obligations under the AD. Operators must therefore treat the SB’s instructions as the compliance standard; any conflict between the AD and the SB is resolved in favour of the AD’s mandatory aspects, but the AD does not provide technical detail beyond its short summary statements, so adherence to the SB is necessary.

• Records and modification history matters. The AD’s Part I exception for Group A aircraft "already modified in accordance with New Piper Aircraft Service Bulletin (SB) No. 1139, dated 28 August 2003" means that prior compliance with the manufacturer’s older SB is relevant to the AD’s application. That creates an explicit dependency on aircraft modification history and the operator’s records to establish whether Part I duties apply (Requirement 1).

• No stated conflict resolution within the instrument. The text does not specify how to handle deviations from the SB (for example, non‑standard parts or alternative methods), nor does it reference an alternative method of compliance (AMOC) process within the AD text. Where a conflict arises between the AD and other legal obligations (for example, conflicting maintenance instructions), the AD does not lay out a formal resolution within its text; operators must therefore consult CASA or the SB for guidance and may need to seek approval for alternative methods of compliance outside the AD text.

What the AD does not specify in relation to other laws:

• The instrument does not cite specific legislative provisions under which CASA issues ADs, nor does it state the statutory enforcement powers or appeal avenues. It likewise does not set out how compliance with the AD should be recorded in maintenance logs or continuations of airworthiness records; those interactions will instead be governed by broader civil aviation law and maintenance recordkeeping rules which are not recited in this document.

In short, the AD operates through incorporation by reference to the manufacturer’s SB and aligns itself with the FAA’s corrected AD. The precise administrative and legal interplay with other aviation safety laws and enforcement mechanisms is not described within this instrument and must be understood by consulting CASA procedural guidance and the cited documents.

The instrument itself is an amendment labelled AD/PA‑46/32 Amdt 1, and the Background paragraph explains the reason for the amendment. The text states that Amendment 1 is issued in response to the issuance of a corrected copy of the related FAA AD (corrected FAA AD 2004‑14‑12 Amdt 39‑13721). The Background specifies that "the only part requiring correction of this Directive was Requirement 1. text, 'Part I of SB No. 1139 dated 9 April 2004' which was changed to 'Part I of SB No. 1139A dated 9 April 2004'." That is the only amendment recorded in the instrument’s text (Background).

Chronology evident from the text:

• Original service bulletin and earlier modification. The AD acknowledges an earlier New Piper Service Bulletin No. 1139 dated 28 August 2003, which, if installed on certain Group A aircraft, exempts those aircraft from the Part I inspection and replacement duty under this AD (Requirement 1 exception).

• Corrective service bulletin reference. The AD amends its internal cross‑reference to the manufacturer’s service bulletin from SB No. 1139 dated 9 April 2004 to SB No. 1139A dated 9 April 2004. The instrument indicates that Amendment 1 was issued to reflect the corrected FAA AD and thereby to correct the AD’s own reference to the updated service bulletin identifier (Background).

• Effectivity and signature dates. The amendment states it becomes effective on 17 March 2005 and is signed by the CASA delegate on 4 February 2005 (This Amendment becomes effective on 17 March 2005; David Punshon, Delegate of the Civil Aviation Safety Authority, 4 February 2005). The Background also ties the amendment to FAA AD corrections issued earlier (the FAA AD reference includes its amendment number).

What the amendment does not show:

• No other legislative history, successive amendments, or revocation language are contained in the provided text. The instrument does not list an original AD issue date in the body of this excerpt nor does it contain a serial revision log beyond the explanation that Amendment 1 corrected a specific internal reference. The AD’s own compliance times are stated to "remain unchanged by this issue" (Compliance), indicating that the amendment is limited in scope to textual correction rather than substantive timing changes.

Operators should therefore read this document as a narrowly drafted amendment whose stated purpose is the correction of the service bulletin citation in Requirement 1 to SB No. 1139A dated 9 April 2004 and whose effect otherwise maintains the AD’s original compliance timelines and safety requirements.

The document contains no information about litigation. It does not reference any court proceedings, administrative appeals, or legal challenges to the AD or its predecessor forms within the text provided.

What the AD does state that is relevant to legal context:

• The AD was issued by the Civil Aviation Safety Authority, signed by a delegate (David Punshon), and contains mandatory compliance language with deadlines and "before further flight" replacement requirements (This Amendment becomes effective on 17 March 2005; David Punshon, Delegate of the Civil Aviation Safety Authority). The presence of a regulatorally issued AD implies potential enforcement mechanisms under the regulator’s broader statutory framework, but the instrument does not record any legal disputes or litigation arising from its issuance.

What is absent and should be noted by readers:

• No mention is made of any appeals process, disputes, or precedent about the enforceability of the AD. The instrument does not document any stay of compliance, court injunction, or settlement. If a practitioner needs to know whether an AD has been contested successfully, whether civil penalties were imposed in disputed cases, or whether an alternative method of compliance was litigated, that information is not in this text and would need to be sought from CASA records, court registers, or other public sources beyond the AD itself.

• Because this excerpt includes only the amended AD text and its background, it lacks subsequent administrative or judicial history. For a complete picture of any litigation, practitioners must consult external legal and regulatory case records.

In sum, the provided document records no litigation history.

The AD’s brevity and reliance on external service bulletin text create several practical pitfalls and interpretation traps for operators and maintenance providers. The following points are grounded in the instrument’s wording and the mechanics it prescribes.

• Serial number specificity. The applicability is strictly delimited by serial number ranges for two PA‑46 model variants split into Group A and Group B. Operators should not assume model designation alone determines applicability; they must verify the airframe serial number against the ranges listed. Misreading the groups or serial ranges could lead to incorrect compliance or unnecessary work (Applicability).

• Records‑based exception for Part I. The AD exempts "aircraft listed in Group A that are already modified in accordance with the New Piper Aircraft Service Bulletin (SB) No. 1139, dated 28 August 2003" from Part I. That exemption is contingent on documented evidence of the earlier SB modification. Absent clear maintenance records, an operator cannot rely on the exemption and will need to perform Part I inspections and any required replacements (Requirement 1 opening clause).

• Ambiguous phrasing on the nut plate test. Requirement 1(b) states: "Inspect the nut plate for sufficient locking characteristics. If the screw can be fully inserted into the nut plate by hand (one thread showing past end of nut), then replacement of the nut plate is required before further flight." The parenthetical phrase and the phrase "fully inserted by hand" create an odd tension: "fully inserted by hand" suggests easy entry, while the parenthetical "one thread showing past end of nut" is precisely the minimum engagement metric stated elsewhere. Careful reading is required to reconcile the AD’s physical test with the intended pass/fail threshold. Operators should use the manufacturer’s SB text (Part I) for the definitive procedural description because the AD itself relies on the SB for the method (Requirement 1(b); Requirement 1(a) notes minimum one thread showing past end of the nut plate). The AD’s amendment corrected the SB citation to SB No. 1139A dated 9 April 2004, so practitioners should use that SB as authoritative for the exact inspection technique and acceptance criteria (Background).

• Different compliance windows. The Compliance section lists two timeframes after 11 August 2004: 25 hours and 100 hours time in service, and adds "The compliance times remain unchanged by this issue." The AD does not explicitly map which timeframe attaches to which Part of the SB in the compliance table verbatim here, but the surrounding structure implies the shorter 25‑hour window applies to the urgent inspection/replacement in Part I and the longer 100‑hour window applies to the retainer clip installation in Part II. Operators must consult SB No. 1139A to confirm procedural time allocation and plan maintenance scheduling accordingly (Compliance; Requirement).

• Product specificity with limited detail. The AD mandates installation of the retainer clip part number 104687‑002 and use of "Loctite thread‑locking compound" on reassembly. The AD does not specify Loctite grade or acceptable equivalents, nor does it supply installation torque values, removal procedures, or exact part specifications , those technical details are left to the referenced service bulletin. Operators must therefore obtain SB No. 1139A to ensure correct product selection and installation technique (Requirement 1(c); Requirement 2).

• Timing vs effective date. The AD’s compliance times are measured from 11 August 2004, yet the amendment becomes effective on 17 March 2005 and is signed on 4 February 2005. Practically, this means operators must check whether the 25‑ or 100‑hour windows have already elapsed since 11 August 2004 and act immediately if so. The AD itself notes the compliance times "remain unchanged by this issue," so operators cannot assume the amendment creates new time to comply (Compliance; This Amendment becomes effective on 17 March 2005).

• Cross‑reference to FAA AD. The Note states that "Corrected FAA AD 2004‑14‑12 Amdt 39‑13721 refers." Practitioners should not treat the AD as technically self‑contained; the FAA AD and the service bulletin likely contain further technical detail and context. Reliance on the AD alone risks missing necessary procedural detail contained in those referenced documents (Note; Background).

• "Before further flight" requirement. The AD requires replacement before further flight when insufficient thread engagement or inadequate nut plate locking is found. That operational constraint means aircraft may be grounded until parts and competent maintenance resources are available. Operators should plan for potential aircraft downtime and ensure access to the specified retainer clip part and authorised maintenance capability (Requirement 1(a)-(b)).

• Single‑screw attachment history. The Background identifies a prior incident involving a Model PA‑28‑181 where a single attachment screw unscrewed and allowed the control wheel to spin freely; the AD applies the risk insight to PA‑46 series aircraft. Given the gravity of the failure mode described, operators should not treat the AD’s required actions as optional mitigations (Background).

Given these features, the main operational "gotchas" are reliance on correct serial‑numbered applicability, requirement to provide documentary proof of prior SB compliance to claim exemptions, ambiguity in the terse AD wording that must be clarified by consulting SB No. 1139A, and the short compliance windows which may already have elapsed relative to the AD’s effective date.

The AD ties compliance explicitly to Part I and Part II of New Piper Service Bulletin No. 1139A dated 9 April 2004. The following stepwise approach takes the AD’s text at face value and sets out actions operators and maintenance providers must take, anchored to the AD language.

1. Confirm applicability.

   • Verify the aircraft model and airframe serial number against the applicability table. The AD applies to specific serial ranges of PA‑46‑350P Mirage and PA‑46‑500TP Meridian in Group A and Group B (Applicability).
   • If the aircraft is in Group A, check maintenance records to establish whether it was already modified in accordance with New Piper SB No. 1139 dated 28 August 2003. Where that prior SB is recorded as installed, Part I obligations do not apply to that aircraft (Requirement 1 opening clause).

2. Obtain the referenced service bulletin.

   • Acquire New Piper Service Bulletin No. 1139A dated 9 April 2004 and review Part I and Part II instructions in full. The AD requires work "in accordance with" those parts, so the SB is the procedural authority for the inspections and installations (Requirement 1 & 2; Background).

3. Schedule and perform Part I actions where applicable.

   • For Group A aircraft that are not already modified under SB No. 1139 dated 28 August 2003, conduct the required inspection of the control wheel attachment screw for proper thread engagement, applying the AD’s stated acceptance threshold ("minimum one thread showing past the end of the nut plate") (Requirement 1(a)).
   • Replace the attachment screw before further flight if the thread engagement is insufficient (Requirement 1(a)).
   • Inspect the nut plate’s locking characteristics. If the screw can be fully inserted into the nut plate by hand (parenthetical in the AD: "one thread showing past end of nut"), replace the nut plate before further flight (Requirement 1(b)). Use the SB’s detailed procedure for the intended test method and pass/fail criteria.
   • Reassemble the control wheel onto the control wheel shaft and install the attachment screw using Loctite thread‑locking compound, as required by Part I of the SB (Requirement 1(c)). The SB should specify the recommended Loctite type, torques and any other installation details.

4. Schedule and perform Part II actions for both Group A and Group B aircraft.

   • Install retainer clip part number 104687‑002 in accordance with Part II of SB No. 1139A. Procurement of the exact part number is required by the AD; installation must follow the SB’s specified method (Requirement 2).

5. Observe the compliance windows.

   • Ensure the Part I action (inspection/replacement/Loctite reassembly) is completed within the AD’s urgent timescale, stated as "within 25 hours time in service after 11 August 2004" where that requirement applies (Compliance). If the aircraft has already accrued more than 25 hours since 11 August 2004, treat the requirement as immediately due.
   • Ensure the Part II action (retainer clip installation) is completed within the AD’s timeframe, stated as "within 100 hours time in service after 11 August 2004" (Compliance). Again, if the aircraft has already exceeded that interval, proceed immediately.

6. Maintain documentary evidence.

   • Record inspection findings, part numbers of any replaced screw or nut plate, the part number of the fitted retainer clip (104687‑002), and the Loctite product used. Because Part I exemptions are contingent on prior SB No. 1139 installations, retain records proving prior modification where applicable (Requirement 1; Requirement 2).
   • Document the hours time in service at which compliance work was performed, and if the "before further flight" condition arose, document the grounding duration and maintenance actions taken.

7. Use qualified personnel and authorised procedures.

   • The AD requires specific hardware and a thread‑locking compound and references the manufacturer’s SB for the installation method. Use appropriately qualified maintenance engineers and follow the SB instructions exactly to ensure compliance with the AD’s mandatory language (Requirement 1 & 2).

8. Coordinate with the regulator if uncertain.

   • Where ambiguity arises (for example, precise interpretation of the nut plate test phrasing in the AD, acceptable Loctite grade or alternative parts), operators should consult CASA or follow any procedures outlined in SB No. 1139A for alternative methods of compliance; the AD text itself does not specify alternative approvals (Background; Requirement).

9. Consider operational scheduling and parts availability.

   • Given the "before further flight" replacement requirement for failed inspections and the short compliance windows measured from 11 August 2004, plan for the potential immediate need to source part 104687‑002, replacement screws and nut plates, and to perform the maintenance without delay (Requirement 1(a)-(b); Requirement 2; Compliance).

In sum, strict adherence to the steps in Part I and Part II of New Piper SB No. 1139A dated 9 April 2004, within the AD’s stated hours thresholds and with careful retention of records (particularly where prior SB No. 1139 dated 28 August 2003 modifications are claimed), is the compliant pathway outlined by the AD. The AD’s text is intentionally concise and delegates the technical detail to the SB; therefore obtaining and following that SB is indispensable.