AD/PA-38/16 Amdt 1 - Main Landing Gear Attach Bolts - Modification

Two core regulatory concepts are present in the AD text: a targeted applicability rule which identifies affected aircraft by model and serial number; and a mandatory compliance instruction which ties a specific service bulletin to a statutory directive.

Applicability is defined in a single sentence: "Applicability: All model PA-38-112 with S/Nos. 38-78A0001 to 38-82A0110." That defines the discrete population of aircraft to which the AD applies. The AD then identifies the technical document controlling the work as "Piper SB No. 673A." In AD practice, when an AD references a manufacturer's service bulletin and states it as the document, the implication in the AD text supplied is that the SB contains the technical method, parts, and any detailed steps required to comply.

The compliance timeframe in the AD is explicit and formulaic: "Unless already accomplished within 100 hours time in service after 31 December, 1982." The AD therefore establishes a performance window measured in hours time in service and tied to a calendar date. The phrasing implies that compliance within that hours block is mandatory unless the work was already performed prior to that compliance obligation coming into force.

The AD also contains a note which extends the obligation beyond those who have not carried out the earlier SB. The Note states: "Aircraft which have complied with SB673 are required to comply with SB.673A." That makes clear that an earlier action taken under SB673 does not relieve an operator from the later, superseding SB673A requirement. The AD’s background sentence explains why: SB673 is "superseded by SB673A", and SB673A "introduces new improved high tensile bolts and provides proper installation and torqueing procedures." The AD therefore converts what would otherwise be a voluntary or recommended manufacturer bulletin into a compulsory modification, as of the AD's terms.

The background also says the amendment "is reissued to avoid possible ambiguity." That signals that the textual form of Amdt 1 has been adjusted relative to an earlier draft or version in order to clarify scope or timing. The AD text supplied does not contain the original version that was being corrected, but the inclusion of that statement functions as the AD's own explanation for reissuing Amdt 1.

Finally, the AD links the technical measure to a safety objective by singling out the "Main Landing Gear Attach Bolts" as the locus of the directive. The AD does not in the supplied text detail failure modes, incidents, or quantified risk, but the structure , an aircraft-type specific directive requiring replacement or modification of a primary structural attachment bolt , indicates that the AD is intended to alter hardware and installation practice for the landing gear attach points, via the specific SB673A measures: extension of serial number effectivity, replacement with "improved high tensile bolts", and specification of "proper installation and torqueing procedures."

The AD identifies a narrow set of direct subjects: all PA-38-112 aeroplanes with serial numbers from 38-78A0001 to 38-82A0110. That is the universe of aircraft to which the directive is addressed, as shown by the line "Applicability: All model PA-38-112 with S/Nos. 38-78A0001 to 38-82A0110." Anyone owning, operating, maintaining or certificating those aircraft within Australia is directly affected by the directive because the AD makes compliance mandatory for that aircraft cohort under the Schedule of Airworthiness Directives heading.

Beyond owners and operators, entities that perform maintenance work on those aircraft are affected in that they must follow the specified service bulletin for the modification, where relevant documentation is indicated by "Document: Piper SB No. 673A." Maintenance organisations, maintenance personnel, and parts suppliers engaged in supplying the new "improved high tensile bolts" will be involved in executing the AD in practice. The AD text does not identify specific maintenance organisations or certificated personnel, nor does it impose explicit qualifications in the text supplied; it confines itself to the technical requirement and the reference to the SB document.

The AD also affects owners who previously complied with the earlier service bulletin. The Note in the AD states that "Aircraft which have complied with SB673 are required to comply with SB.673A." That creates a rework requirement for those who acted under SB673, as the superseding SB introduces different or additional parts and procedures.

The document’s background language about extending "serial number effectivity" has implications for aircraft owners outside the listed serial numbers where the SB673A may reach beyond the S/N range shown in the AD. The AD text supplied gives a specific S/N range for applicability, and also states that the SB "extends serial number effectivity." That suggests either that the service bulletin itself treats a different or larger S/N universe, or that SB673A explicitly enlarges the model/serial range compared with SB673. The AD as presented binds the specific S/N group, so practitioners must reconcile the AD’s S/N list with any broader S/N guidance inside SB673A.

Who pays: the AD does not set out cost recovery or funding. The practical allocation of costs is inferable from the AD structure. The directive requires the modification for the affected aircraft; the owner/operator is the party responsible for ensuring AD compliance. The AD text contains no financial assistance, no cost caps, and no imports of parts supply obligations. Therefore compliance costs: parts, labour and aircraft downtime will be borne by the operator or owner, and by any contracted maintenance provider for labour, unless commercial arrangements between parties allocate those costs otherwise. The AD text itself does not define those allocations.

Who decides: the AD places the substantive technical decision on the referenced service bulletin, "Piper SB No. 673A." That is the controlling technical document for what must be done. The AD issuer has chosen to require the SB’s measures; the operator or maintenance organisation must follow the SB to satisfy the AD. The AD text does not contain an administrative review or appeal procedure, nor does it state any alternative methods of compliance in the supplied text.

The AD text imposes a limited set of duties and defines a small amount of affirmative action. The central duty is to carry out the main landing gear attach bolts modification as described in the referenced document. The AD states that duty as follows: "Document: Piper SB No. 673A" and "Compliance: Unless already accomplished within 100 hours time in service after 31 December, 1982." Read together, those lines create the duty to perform the SB673A modification, unless the modification was already completed within the stated 100 hour window.

The AD also imposes a secondary duty on operators who previously complied with Piper SB673. The Note states: "Aircraft which have complied with SB673 are required to comply with SB.673A." That creates an affirmative duty to rework or to perform additional steps required by the superseding SB, even if the earlier SB was completed.

The AD’s technical content, as summarised in the background, imposes a further substantive requirement indirectly: the replacement or installation of "new improved high tensile bolts" and adherence to "proper installation and torqueing procedures." Although the AD text itself does not give the bolt part numbers or torque values, it makes those technical changes mandatory by referencing the SB and by stating the nature of the changes. Thus the duty includes using the improved bolts and following the installation and torqueing procedures in SB673A.

Rights: the AD text supplies no explicit rights such as an appeal route, relief from compliance, or permission for an alternative means of compliance. There is no textual provision within the supplied AD that allows operators to apply for an alternative method or to delay compliance beyond the "100 hours time in service" window. Practitioners should therefore treat the AD as setting firm, albeit narrowly described, obligations without an express rights framework included in the text.

Conditional exemptions: the AD contains a conditional exemption for aircraft that have already accomplished the work within the stated time window. The specific phrase is "Unless already accomplished within 100 hours time in service after 31 December, 1982." That functions as an exception: if the SB673A measures were already completed within that 100 hours time-in-service window, the owner/operator need not do further work. The Note, however, removes a different exemption: earlier compliance with SB673 is not an exemption from SB673A.

Record-keeping and evidence of compliance: the AD text itself does not lay out record-keeping requirements. Because the AD ties compliance to accomplishment of the SB work, demonstrating compliance will require access to evidence that the SB actions were completed within the stated hours window. The AD text does not, however, specify the form or repository for such proof.

Delegation and contractor duties: the AD text does not specify who must perform the modification. It points to the SB as the controlling technical document, implying that the modification must meet the SB instructions. The AD does not limit performance to particular certificated maintenance organisations in the text provided, and it does not specify who bears liability. Those matters are not addressed in the AD text supplied.

The AD text supplied does not set out any penalties, sanctions, or enforcement processes. The only enforcement-relevant indication in the document is its classification under the Commonwealth heading "Civil Aviation Regulations 1998, PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES." The AD itself contains no wording that specifies a penalty, a fine, a suspension, a remedial order, or an administrative process. The AD text does not include any compliance monitoring provisions or any process for the issuer to verify completion.

Because the AD text contains no express enforcement or penalty provisions, a practitioner relying solely on this document must treat enforcement mechanisms as not specified in the AD text supplied. The AD requires a modification be accomplished "within 100 hours time in service after 31 December, 1982" unless previously completed. The directive form creates a mandatory obligation for the affected aircraft under the Schedule of Airworthiness Directives heading, but the document does not itself describe how non-compliance will be detected or what penalty will follow.

Practical enforcement considerations that follow from the document’s structure, without being stated in it, include the following points. The AD makes compliance contingent on demonstrable accomplishment of SB673A. Therefore a lack of records showing accomplishment could be treated as a lack of compliance. The AD’s note that SB673 compliance does not satisfy SB673A means that maintenance history must be examined to determine whether the relevant improved-bolt installation and torqueing procedures of SB673A were followed, rather than merely noting that some earlier SB work was completed. That increases the evidentiary burden on owners/operators to show what specific steps were completed and which bolts were installed.

The AD text does not identify a date of effect beyond the compliance window tied to 31 December 1982 and does not specify how compliance will be confirmed. It also does not provide an express avenue for relief if, for example, parts are unavailable or if an operator cannot meet the hours window. Those matters are not addressed in the supplied document.

In short, the AD imposes mandatory work but supplies no textual enforcement or penalty provisions. Any enforcement procedures, certified processes for verification, or sanctioning mechanisms would need to be located in other instruments or in administrative practice outside the text given.

The supplied document sits under the Commonwealth header specifying "Civil Aviation Regulations 1998, PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES." The AD text itself interacts directly with manufacturer documentation by superseding and referencing service bulletins. Specifically, the AD text states "Piper SB673 is superseded by SB673A" and it identifies "Document: Piper SB No. 673A" as the controlling technical source. The AD therefore operates by incorporating a manufacturer’s technical directive into the Schedule of Airworthiness Directives framework.

The AD text does not identify any other statutory provisions, regulatory exemptions, or cross-references to other parts of the regulations. The only explicit cross-document interaction the AD supplies is the relationship with the previous service bulletin SB673, and the directive that those who complied with SB673 must now comply with SB673A. Absent additional text, no other regulatory instruments are invoked or modified in the supplied AD.

Because the AD is titled and formatted as part of the "Schedule of Airworthiness Directives", it presumably forms part of a body of ADs applied to aircraft under the Civil Aviation Regulations heading used at the top of the document. The AD text provided does not, however, include any express statement about whether compliance with SB673A substitutes for other maintenance obligations, or whether it interacts with continuing airworthiness obligations beyond the immediate modification. The document does not state whether accomplishment of SB673A must be entered into maintenance logs or how it interacts with maintenance release procedures.

The most direct interaction spelled out in the text is between the earlier manufacturer action and the new, mandatory converter: SB673 has been superseded by SB673A, and the AD binds SB673A to the listed aircraft. That creates a temporal and substantive interaction: earlier compliance under SB673 is insufficient, because SB673A introduces "improved high tensile bolts" and "proper installation and torqueing procedures". The AD therefore mandates a change from the previously acceptable technical practice to the new technical practice specified in SB673A.

The AD does not address whether alternative methods of compliance are permissible, or whether an equivalent bolt and torque procedure not listed in SB673A would be acceptable. The AD text references the SB as the controlling document; so for the purposes of this AD the SB is the technical standard. Any interaction with other regulatory obligations, such as airworthiness certification, maintenance release or continuing inspection regimes, is not detailed in the AD text supplied.

The AD is presented as "AD/PA-38/16 Amdt 1." The AD text contains a short amendment history description in the Background paragraph. That background states the following:

• "Amdt 1 to AD/PA-38/16 is reissued to avoid possible ambiguity." That indicates that Amdt 1 was reissued rather than being a first-time issuance or a mere correction; the AD explains the reissue's purpose as clarifying ambiguity.

• "Piper SB673 is superseded by SB673A." That records a discrete change in the manufacturer's technical guidance from SB673 to SB673A.

• The background further states that SB673A "extends serial number effectivity, introduces new improved high tensile bolts and provides proper installation and torqueing procedures." Those three items constitute the substantive changes that underlie the amendment.

The AD text does not provide prior versions or dates of initial issue except insofar as the compliance window is tied to a calendar date, "after 31 December, 1982." The AD does not list the original issue date of AD/PA-38/16 nor does it provide a version history or a list of changes beyond the single Amdt 1 reissue and the supersession of SB673 by SB673A.

The compliance clause "Unless already accomplished within 100 hours time in service after 31 December, 1982" suggests that the AD relates to actions within the early 1980s. The AD does not provide any later amendments, revocations, or further supersessions in the text supplied. No subsequent amendments or revocations are mentioned.

Practitioners should interpret the amendment history as confined to the single reissue of Amendment 1, which was reissued to remove ambiguity and to bind SB673A in lieu of SB673. The AD text does not provide a running amendment ledger, and it does not list the specific differences between SB673 and SB673A beyond the three points already quoted. The AD does not include the exact language of SB673A, nor does it include an attachment of the SB itself.

The supplied AD text contains no litigation history, no references to judicial decisions, and no citations to administrative appeals or disputes. There are no case names, no mentions of proceedings, and no summary of any enforcement action arising from AD/PA-38/16 Amdt 1. The document is strictly a directive and explanatory note; it does not narrate any legal challenges or rulings.

Given the absence of litigation material in the AD text, the document does not provide any judicial or tribunal interpretation that might clarify compliance obligations, enforcement scope, or the meaning of ambiguous language. The line in Background that says the Amdt "is reissued to avoid possible ambiguity" suggests that ambiguity existed in an earlier version, but the AD text does not record any dispute or case law that arose from that ambiguity.

For practitioners seeking litigation or precedent on the meaning or enforceability of this AD, the supplied document contains nothing to that effect. Any such history would need to be located in other sources outside the AD text given here.

The AD text contains several features that may create practical pitfalls for owners, operators, and maintenance providers. These are matters to note when interpreting obligations and planning compliance. All points here are grounded in the AD text supplied.

1. Serial number specificity and the "extends serial number effectivity" language. The AD labels its applicability as "All model PA-38-112 with S/Nos. 38-78A0001 to 38-82A0110." At the same time, the Background notes that SB673A "extends serial number effectivity." That can create a trap: if SB673A, the controlling technical document, lists a different or broader list of serial numbers than the AD, a practitioner must reconcile the AD’s specific S/N list with the SB’s effectivity statement. The AD itself binds the S/N range it states, but it also says the SB extends effectivity; that could cause confusion about whether aircraft just outside the AD’s listed S/Ns are intended to be subject to the SB requirements.

2. Earlier compliance under SB673 does not finish the matter. The Note states: "Aircraft which have complied with SB673 are required to comply with SB.673A." Operators who believe their maintenance history exempts them because they followed SB673 will need to re-examine whether the earlier work matches SB673A’s improved bolt specification and torqueing procedures. The practical consequence is potential rework even for aircraft with ostensibly recent service history.

3. Compliance timing phrasing. The compliance clause reads "Unless already accomplished within 100 hours time in service after 31 December, 1982." The construction ties an hours-in-service window to a calendar date. The Background’s statement that the amendment was "reissued to avoid possible ambiguity" signals that the original text may have been misunderstood. Operators must therefore document when the SB work was done relative to the 31 December 1982 benchmark and relative to 100 hours time in service, to demonstrate that the work was accomplished within the stated window, if that is relied upon to claim compliance.

4. The AD references SB673A for the technical details but does not reproduce them. The AD requires the use of "new improved high tensile bolts" and "proper installation and torqueing procedures" as per SB673A, but the AD text supplied does not include part numbers, torque values, or installation drawings. Implementing the AD therefore requires obtaining SB673A. Failure to consult the SB will prevent proper compliance because the AD intentionally delegates the technical specifics to the service bulletin.

5. No listed enforcement or appeal process. The AD contains no express penalty or enforcement provision. The absence of specified enforcement mechanisms in the AD text may leave owners uncertain about proof of compliance required by regulators or third parties. That lack of specification is a procedural gotcha: operators must retain clear records showing SB673A compliance since the AD itself does not say how compliance is to be evidenced.

6. Possible mismatch between maintenance practice and AD wording. The AD’s demand for "proper installation and torqueing procedures" as a substantive change may mean that superficial checks or torque inspections are insufficient if the SB calls for bolt replacement and specific installation steps. Operators who think a simple torque check satisfies the AD may be mistaken if SB673A prescribes bolt replacement plus torque values.

7. Timing of parts availability. The AD requires "new improved high tensile bolts," but the AD text does not specify part sourcing, lead times, or alternative parts. If the improved bolts were not readily available at the time the AD became effective, an operator could encounter practical difficulty meeting the "100 hours time in service after 31 December, 1982" deadline. The AD text does not provide relief for such supply issues.

8. Record sufficiency where earlier work was done. When asserting that SB673 work was previously completed, operators must be able to show that the earlier work matches what SB673A requires. The AD text’s explicit note that SB673 compliance does not obviate SB673A means records of parts used and installation procedures will be pivotal. Partial or ambiguous records can create compliance disputes, and the AD text does not prescribe the form of evidence required.

9. Narrowness of aircraft identification. The AD is expressly limited to PA-38-112 models with the specified S/N range. Operators of other PA-38 variants or adjacent serial numbers must not assume they are covered by this AD. Conversely, if SB673A does in fact extend effectivity beyond those serial numbers, operators must identify whether subsequent ADs or other documents incorporate that broader scope. The AD text supplied contains no such follow-on instruments.

10. Reissue language indicating prior ambiguity. The statement that "Amdt 1 ... is reissued to avoid possible ambiguity" warns that the current text was intended to clarify. Practitioners should be conscious that earlier communications or versions could have been inconsistent and should not rely on outdated memoranda or prior drafts.

Each of these gotchas flows directly from the language appearing in the AD and the interplay between the AD and the referenced service bulletin. Because the AD delegates technical specifics to the SB, failure to obtain and follow SB673A is the most practical source of non-compliance risk.

Compliance with this AD, as stated in the document, requires completing the main landing gear attach bolt modification using Piper Service Bulletin No. 673A within the stated time window unless the work was already accomplished within that window. The AD gives specific, orderly steps implied by its text. The following actions derive directly from the AD content and from the obligations the AD imposes.

1. Determine applicability. Review the aircraft’s serial number and model. The AD applies to "All model PA-38-112 with S/Nos. 38-78A0001 to 38-82A0110." Confirm the aircraft’s serial number falls within that inclusive range. If it does not, the AD, as presented, does not apply to that aircraft.

2. Obtain Piper SB No. 673A. The AD identifies "Document: Piper SB No. 673A" as the controlling technical document. The AD text does not reproduce the SB, so obtaining the full SB673A is an essential compliance step. SB673A will contain the part numbers for the "new improved high tensile bolts", installation steps, torqueing values, and any special tooling or inspection steps required.

3. Check prior maintenance history. Review maintenance records for evidence that SB673A work was already completed within the relevant time window. The compliance clause reads "Unless already accomplished within 100 hours time in service after 31 December, 1982." If the SB673A work was completed within that window, no further action is required under the AD. If only SB673 (the earlier bulletin) was completed, the Note makes explicit that "Aircraft which have complied with SB673 are required to comply with SB.673A." In that case, SB673 compliance does not satisfy the AD; SB673A must be completed.

4. Schedule and execute the SB673A work. If the aircraft is applicable and SB673A has not been completed within the stated window, arrange for the work to be performed. The AD mandates the use of the "new improved high tensile bolts" and "proper installation and torqueing procedures" as specified in SB673A. The AD does not limit who may perform the work in its text, but the technical steps must follow the SB. Ensure that the bolts used match the part specification in SB673A and that torqueing is performed to the SB’s specified values and procedures.

5. Document the work. The AD itself does not provide a form or repository for evidence, but the AD’s compliance requirement is contingent on showing that SB673A has been accomplished. Create and retain maintenance records that show the work performed, the parts installed (including part numbers or description of the "improved high tensile bolts"), the torque values applied, the date and time in service at the work’s completion, and the identity of the person or organisation that performed the work. These records will be necessary to demonstrate compliance to any third party or regulator, because the AD text does not describe alternative proof standards.

6. Reconcile serial number effectivity. The AD indicates SB673A "extends serial number effectivity." Review SB673A to confirm whether it applies to additional serial numbers beyond those listed in the AD. If the SB applies to a broader S/N set, record why the AD’s applicability is limited to the listed S/Ns, and seek clarification from the issuing authority or the manufacturer if there is uncertainty.

7. Follow SB technical details exactly. The AD requires the "proper installation and torqueing procedures" from SB673A. That means any deviation from the SB’s steps, such as using a different torque value or an alternate bolt not specified in SB673A, could be inconsistent with the AD as written. If an alternative method is being considered, do not assume it satisfies the AD absent an express allowance in the AD; the AD text does not provide for alternative methods.

8. Verify time-in-service compliance outcomes. If relying on the "Unless already accomplished within 100 hours time in service after 31 December, 1982" clause to claim prior compliance, confirm and verify the aircraft’s time in service at the date of the work. The AD ties the 100-hour measurement to the date "after 31 December, 1982." Recordkeeping should make clear whether the work was done within that hours bracket.

9. Maintain awareness of further ADs or communications. The AD text supplied is limited to Amdt 1 and the immediate supplanting of SB673. It does not provide later amendments or revocations. Consequently, periodically check for any subsequent ADs or updates that may alter the obligation. The AD text itself contains no schedule or mechanism for later change.

10. When in doubt, consult the SB and the issuing authority. Because the AD delegates technical detail to SB673A and because the AD text notes that Amendment 1 was reissued "to avoid possible ambiguity," any ambiguity encountered in reconciling the AD text and the SB should be referred to the issuer or to the aircraft manufacturer for clarification. The AD text does not describe an administrative appeal process, but direct clarification will reduce the risk of incorrect compliance.

These compliance steps flow directly from the wording of the AD. The essential task is to perform the SB673A-referenced modification for the stated serial-numbered aircraft, unless the work was already performed within the 100 hours time-in-service window after 31 December 1982. Proper documentation of parts and torque procedures will be required to show that the AD has been met, because the AD itself places the technical detail in the SB and does not provide alternative compliance pathways in the supplied text.