AD/SWSA226/84 Amdt 1 - Cargo Door Lower Belt Frames

The AD is built around a focused set of airworthiness concepts: targeted inspection, conditional repair or replacement, and mandatory reinforcement where no defects are found. The technical locus is the cargo door lower belt frames at the cargo latch receptacles, specified across six belt-frame locations. The AD treats those six frames as a group, using the phrase "all six belt frames" in the instruction to fit reinforcement doublers if no cracks are found.

Key referenced engineering and maintenance material are:

• Fairchild Aircraft SA226 Series Service Bulletin 226-53-007, issued 7 May 1981, revised 17 February 1992;
• Fairchild Aircraft SA227 Series Service Bulletin 227-53-003, issued 29 January 1986, revised 13 February 1986;
• SA226 / 227 Structural Repair Manual (SRM), Section 53-90-20, initial issue 1 March 1983, Revision 24 dated 27 August 1997;
• Fairchild Aircraft Approved Repair Procedure ARP 53-30-9701, dated 28 July 1997.

The AD separates routine mitigation from corrective action. The inspection, from Part A of the SBs, is the entry control measure; if cracks are present, the AD requires immediate corrective work tailored to location and damage; if no cracks are found, the AD requires a preventive reinforcement action, installation of reinforcement doublers per Part B of the SBs.

The AD is explicit about which frames require reinforcement doublers when cracked, and which require replacement with new-design frames without doublers. For belt frames at FS 438.060 and FS 491.060 the repair solution includes installing an angle (P/N 27-22206-009 or -010) and the reinforcement doublers (P/N 27-22206-007 and -008). For belt frames at FS 454.501, FS 455.726, FS 473.392 and FS 474.657 the mandated remedy is replacement with new-design frames P/N 27-22207-008, 27-22208-005, and 27-22207-007, and explicitly no doublers are needed for those replacements.

Another organising concept is the temporal compliance regime. The AD specifies three compliance time items: the inspection window (Requirement 1), a before-further-flight mandate for any required repairs following detection of cracks (Requirement 2), and a follow-up window to install reinforcement doublers where no cracks were found (Requirement 3). The AD further links itself to prior regulatory action by stating that compliance with cancelled AD/SWSA226/37 for SA226-AT and SA226-TC models constitutes compliance with this AD, and by referencing FAA AD 98-06-25.

Finally, the safety narrative underpinning the directive is recorded as a factual background: the FAA required actions following a flight decompression incident caused by fatigue at the bottom of a cargo door on a Model SA226-TC, and the AD records the hazard that door failure could cause decompression injury to passengers and substantial structural damage. The AD therefore pairs a narrow structural inspection and repair regime to a specific failure mode cited in the background.

The AD applies to specific Fairchild (Swearingen) SA226 and SA227 model aeroplanes and defined serial-number ranges. The AD lists the applicable models and serial numbers precisely. For SA226-AT, serial numbers AT001 through AT074 are listed; for SA226-TC, serial numbers TC201 through TC419; for SA227-AC, serial numbers AC406, AC415, AC416, AC420 through AC456, AC458 through AC469, and AC471 through AC478; and for SA227-AT, serial numbers AT423 through AT469. Operators and owners of any aircraft within those model and serial-number ranges are subject to the AD’s requirements.

Directly affected parties include the aircraft operators and those responsible for maintenance and continued airworthiness for those aircraft. The AD prescribes inspections and structural work to be performed in accordance with specified manufacturer service bulletins and SRM/ARP documents, therefore organisations performing the work must be able to apply or have access to that manufacturer documentation and to the necessary parts listed by part number. Where repairs require specific part numbers the operator is the de facto purchaser of parts and services required to comply.

Maintenance organisations and certificated engineers who carry out the inspection and corrective actions are affected because the AD requires the work to be done in accordance with the SBs and SRM/ARP referenced. The AD’s instruction that repairs must be accomplished "before further flight" where cracks are found will affect flight scheduling, as aircraft with detected cracks cannot lawfully continue operations until the mandated remedy is fitted; that operational outcome places scheduling and potential grounding costs on the operator.

There is also an indirect regulatory audience: holders of records for prior compliance with AD/SWSA226/37, as the AD states that compliance with that cancelled AD for SA226-AT and SA226-TC models constitutes compliance with this AD. That means an owner/operator can rely on past compliance with the cancelled AD to meet this AD’s requirements, where applicable.

The AD also references FAA AD 98-06-25, which indicates that regulators and entities tracking cross-jurisdictional airworthiness actions should note the linkage between the CASA AD and prior FAA action. Finally, the AD’s focus on specific fuselage-station locations and part numbers makes parts suppliers and repair-parts inventories relevant stakeholders, because compliance requires either fitting the listed retrofit parts or installing the listed new-design frames.

Duties imposed by the AD are concrete and procedural. The principal duties are:

• Inspect, per Requirement 1: Operators must inspect the cargo door lower belt frames at the cargo latch receptacles for cracks in accordance with Part A of the Accomplishment Instructions of Fairchild SB 226-53-007 (SA226) or SB 227-53-003 (SA227), as applicable. The SB numbers, issue and revision dates are specified in the AD text.

• Repair or replace, per Requirement 2: If cracks are found, operators must follow one of two location-dependent remedies. For belt frames at FS 438.060 and FS 491.060, the duty is to repair the belt frame by installing an angle P/N 27-22206-009 or 27-22206-010 in accordance with the SRM Section 53-90-20 or ARP 53-30-9701, and to fit reinforcement doublers P/N 27-22206-007 and -008 together with this repair. For belt frames at FS 454.501, FS 455.726, FS 473.392 and FS 474.657, the duty is to replace all four belt frames with new-design frames P/N 27-22207-008, 27-22208-005, and 27-22207-007, in accordance with the SRM or ARP; the AD states no reinforcement doublers are needed for those new-design replacements.

• Preventive reinforcement, per Requirement 3: If no cracks are found in all six belt frames during the inspection, operators must install reinforcement doublers in all six belt frames in accordance with Part B of the Accomplishment Instructions of the relevant SB.

Temporal duties are explicit: the inspection must be completed within the compliance window specified (the AD states "1. Within 500 hours time in service after 18 June 1998"); any required repairs following detection of cracks must be accomplished "before further flight"; and the installation of doublers where no cracks are found must be completed within 500 hours TIS after accomplishment of the Requirement 1 inspection.

Rights or compliance-relief provisions appearing in the AD are limited and concrete. The AD records that "Compliance with cancelled AD/SWSA226/37 for SA226-AT and SA226-TC model aeroplanes constitutes compliance with this AD." That is an explicit grandfathering-right for operators who complied with the earlier cancelled AD: their earlier compliance satisfies the current directive, for those models. The AD also references FAA AD 98-06-25, but does not convert that reference into any relief; it is a cross-reference rather than a stated right.

The AD does not, within the text provided, state alternative methods of compliance, approval pathways, or discretionary exemptions. It specifies that the work must be done in accordance with the named SBs and SRM/ARP documents, thereby limiting acceptable methods to those referenced service instructions unless an alternate method is otherwise approved by the regulator; the AD text itself does not set out any alternate-method approval procedure.

Who decides operationally: the aircraft operator must schedule and commission the inspections and any corrective actions; a maintenance organisation or certificated engineer will decide the technical execution within the constraints of the SBs and SRM/ARP. The CASA delegate issued the AD; the AD is the regulator's direction. The AD places the duty of adherence and scheduling on the operator and the technical responsibility of execution on the maintenance entity using the specified documentation.

The AD text supplied does not set out civil or criminal penalties, nor does it state an enforcement mechanism or penalty schedule. The instrument is an airworthiness directive issued by the Civil Aviation Safety Authority and signed by a CASA delegate, with an effective date specified. It sets mandatory technical and temporal requirements for the listed aircraft models and serial numbers, including a "before further flight" requirement for repairs where cracks are found, but the AD does not itself include language describing the penalties or sanctions that would follow non-compliance.

Enforcement implications that can be read directly from the AD’s wording are temporal constraints that affect operations. Specifically, Requirement 2 requires that when cracks are found the prescribed repair or replacement must be accomplished "before further flight." That expresses a regulatory limitation on the aircraft's operational status: an aircraft with identified cracked belt frames covered by the AD must have the mandated work done before it can fly again. The AD also sets inspection and installation time windows, creating mandatory scheduling obligations on operators.

The AD references prior and related regulatory actions. It notes that compliance with cancelled AD/SWSA226/37 constitutes compliance with this AD for certain models, and it references FAA AD 98-06-25. Those cross-references indicate regulatory interconnection, but the AD text supplied does not state how CASA will monitor compliance, or what formal enforcement steps CASA will take in cases of non-compliance.

Any practitioner reading this AD should therefore treat the AD’s duties as mandatory technical and temporal obligations, with the AD itself providing the scope and timeline. The document does not identify the enforcement mechanism, penalties or processes for alternative methods of compliance within its text; those matters, if relevant, would need to be identified in CASA guidance or other regulatory material outside the AD text provided here.

The instrument explicitly connects to at least two other items of regulatory and manufacturer documentation. First, the AD states that "Compliance with cancelled AD/SWSA226/37 for SA226-AT and SA226-TC model aeroplanes constitutes compliance with this AD." That creates a direct statutory relationship with a prior CASA AD that has since been cancelled; for the two named SA226 sub-models, performance of the earlier AD’s requirements is treated as satisfying this AD. Practically, this means operators who can demonstrate compliance with the cancelled AD are not required to duplicate the work mandated here, at least to the extent the earlier AD covered the same work for those models.

Second, the AD refers to FAA AD 98-06-25 Amdt 39-10403. The AD’s background states that the FAA requires certain actions as a result of a decompression incident caused by fatigue at the bottom of a cargo door on a Model SA226-TC. The CASA AD therefore aligns its corrective requirements with FAA-identified risk and remedies. The AD is not a text of the FAA AD, but it references that FAA action as part of its background.

The AD also mandates work to be carried out "in accordance with" specified manufacturer service bulletins (SB 226-53-007; SB 227-53-003), SRM Section 53-90-20, and ARP 53-30-9701, all of which are manufacturer-issued documents. Those service and repair documents are technical sources that the AD incorporates by reference into the regulatory requirement. Compliance therefore requires operators and maintainers to follow both the regulator’s directive and the manufacturer’s designated procedures.

Outside the AD text provided there may be broader regulatory frameworks governing methods of compliance, approvals for alternate methods, and enforcement. This AD itself does not reproduce those frameworks, but it interacts functionally with them because it references prior CASA ADs and FAA ADs and requires compliance with specific manufacturer's technical publications. For operators and maintainers this means the AD is to be read as part of the network of airworthiness requirements: the CASA AD sets the legal obligation; the manufacturer documents prescribe the technical steps required to meet that obligation; and prior ADs may be relied upon where the AD expressly so provides.

In short, the AD creates direct obligations tied to specific service documents, references an earlier cancelled CASA AD as satisfying this AD for certain models, and situates itself in the technical lineage of an FAA AD prompted by a decompression incident. The AD text supplied does not change or restate broader aviation law, but it integrates with these other instruments by cross-reference and by incorporating the manufacturer’s service instructions as the method of compliance.

The document presented is AD/SWSA226/84 Amendment 1. The amendment is dated 17 June 2009 by David Villiers, Delegate of the Civil Aviation Safety Authority, and the AD states that "This Amendment becomes effective on 30 July 2009." The AD text explicitly states that "This AD is amended to reference relationship between this AD and cancelled AD/SWSA226/37." That sentence records the narrow purpose of the amendment: to clarify or record the relationship between AD/SWSA226/84 and the earlier cancelled AD/SWSA226/37.

The AD text also contains historical service-document dates that are relevant to the amendment’s technical content. It references Fairchild Aircraft SB 226-53-007 issued 7 May 1981 and revised 17 February 1992, and SB 227-53-003 issued 29 January 1986 and revised 13 February 1986. It references SRM Section 53-90-20 initial issue dated 1 March 1983 and Revision 24 dated 27 August 1997, and ARP 53-30-9701 dated 28 July 1997. These dates contextualise the technical instructions the AD mandates and indicate the vintage of the manufacturer material being incorporated.

The AD’s compliance section contains timeframes tied to a historical date: "Within 500 hours time in service after 18 June 1998" for the initial inspection. That places the nominal inspection compliance window starting from 18 June 1998, even though this Amendment becomes effective in 2009. The AD therefore records compliance obligations that reference prior regulatory timelines. The AD also notes that FAA AD 98-06-25 Amendment 39-10403 is relevant, which ties the CASA AD’s technical lineage back to the FAA action from 1998.

Aside from the explicit statement that the Amendment references a relationship with a cancelled AD and the effective date, the AD text does not list earlier amendment versions of AD/SWSA226/84; nor does it provide an amendment log beyond the statement that this instrument is Amdt 1 and the effective date. The AD does include a note that "This AD is amended to reference relationship between this AD and cancelled AD/SWSA226/37," which is the only described change recorded in the body of the AD provided.

Practitioners seeking the full amendment and revision trail should, based on the AD text, consult CASA records for AD/SWSA226/84 and the cancelled AD/SWSA226/37, and the FAA AD referenced, since the AD text signals the amendment purpose rather than reproducing a full historical sequence.

The AD text provided does not record any litigation history. There are no references in the instrument to legal challenges, court decisions, administrative appeals, or other litigation connected to AD/SWSA226/84 Amdt 1. The only adjudicative or decision-making name present is that of David Villiers, a CASA delegate who signed the Amendment on 17 June 2009.

Because the AD text itself is silent on litigation, practitioners should treat the directive as a regulatory instrument whose compliance obligations are described in the document, and, if they require information about any legal challenges or precedential decisions interpreting the AD, they must search external legal and administrative records, which are not contained in the AD text provided. The AD does not specify dispute resolution mechanisms or appeal rights within its text; therefore any procedural rights or precedents would be found in CASA’s administrative law framework or broader aviation law, not in the AD itself.

The AD does reference other regulatory actions, namely the cancelled CASA AD/SWSA226/37 and FAA AD 98-06-25, but it does not record any adjudicated disputes regarding those instruments. If recorded legal history exists, it is not present within the supplied AD text.

Several interpretive and practical points in the AD can cause misunderstanding or operational friction unless read carefully.

1. Compliance windows reference a past date. The inspection requirement (Requirement 1) is to be done "Within 500 hours time in service after 18 June 1998." The Amendment is effective on 30 July 2009. That means the AD’s compliance windows refer back to 1998; practitioners must note that the AD explicitly uses the historical date as the compliance trigger. Operators who read only the Amendment’s effective date might miss that the inspection compliance window is anchored to 18 June 1998.

2. "Before further flight" is mandatory when cracks are found. The AD states for Requirement 2 that if cracks are found the prescribed repairs or replacements must be accomplished, and the compliance table item 2 states "Before further flight." That is an operational stop-gap: an aircraft with a detected crack in the covered belt frames must have the mandated remedy fitted before it can fly further. This is not couched as discretionary; it is a direct compliance timing instruction.

3. Part-number specificity matters. The AD names repair and replacement part numbers precisely. For repairs at FS 438.060 and FS 491.060 the permitted angles are P/N 27-22206-009 or 27-22206-010, and reinforcement doublers are P/N 27-22206-007 and -008. For replacements at four other FS positions the new frame P/Ns are 27-22207-008, 27-22208-005, and 27-22207-007. Using incorrect part numbers would not comply with the AD as written.

4. Location-specific remedies are not interchangeable. For the two FS locations (438.060 and 491.060) the AD requires repair with an angle plus reinforcement doublers. For the other four FS locations the AD requires replacement with new-design frames and explicitly states "No reinforcement doublers are needed for these four new design belt frames." Misapplying the replacement solution to the two FS locations, or omitting doublers where they are mandated, would not follow the AD.

5. "All six belt frames" language can be misunderstood. The AD repeatedly refers to "all six belt frames." The operator must inspect all six frames; if none are cracked then reinforcement doublers must be installed in all six frames per Part B of the SB. If some are cracked, the AD prescribes the repairs/replacements appropriate to the individual FS locations and, where the repair calls for doublers, the doublers must be fitted as part of that repair. The AD does not instruct that doublers be fitted only when every frame is crack-free; it separately prescribes doublers as part of the repair for two FS positions, and as a preventive installation where no cracks are found.

6. Manufacturer documentation version specificity. The AD names specific SB issues and revisions, SRM revision number and date, and an ARP date. Compliance requires following the specified SB/ SRM/ARP references. Operators who attempt to follow earlier or later versions without documented acceptance may stray from the literal AD text.

7. Relationship to cancelled AD. For SA226-AT and SA226-TC models the AD states that compliance with the cancelled AD/SWSA226/37 constitutes compliance with this AD. Operators must ensure they can document prior compliance with the cancelled AD if they intend to rely on that clause.

8. The AD does not state alternative-method approval in its text. The AD does not include an alternate methods-of-compliance clause in the provided text, so operators who wish to pursue an alternative repair or inspection method will need to refer to CASA’s broader procedures or guidance outside the AD to obtain approval, because such a pathway is not described in the AD itself.

9. Cross-jurisdictional references. The AD references FAA AD 98-06-25. That linkage is informational and part of the background; it is not a substitute for following the CASA AD. Practitioners should not assume that compliance with the FAA AD alone is sufficient unless expressly stated; the AD does not state that FAA compliance satisfies CASA obligations, except where it has explicitly stated compliance with a cancelled CASA AD does so.

10. No penalties stated. The AD imposes mandatory work and timing, but it does not set out penalties or enforcement steps in the instrument itself. Non-compliance consequences are therefore not described in the text and must be determined from wider regulatory sources.

These points are all grounded in the AD text and the precise language used. They represent places where misreading or partial reading of the AD could lead to operational non-compliance.

The AD sets a clear, three-step compliance pathway tied to specified time limits and technical references. Below is a stepwise operational checklist grounded in the AD text for an operator or maintenance organisation to follow.

1. Confirm applicability. Identify whether the aircraft is within the listed models and serial-number ranges in the AD: SA226-AT (AT001-AT074), SA226-TC (TC201-TC419), SA227-AC (AC406, AC415, AC416, AC420-AC456, AC458-AC469, AC471-AC478), SA227-AT (AT423-AT469). If the aircraft is not listed, the AD does not apply as written.

2. Obtain the referenced documentation. Acquire the correct service bulletin for the model:

   • SA226: Fairchild SB 226-53-007, issued 7 May 1981, revised 17 February 1992; and
   • SA227: Fairchild SB 227-53-003, issued 29 January 1986, revised 13 February 1986. Also obtain SRM Section 53-90-20 (initial issue 1 March 1983; Revision 24 dated 27 August 1997) and ARP 53-30-9701 dated 28 July 1997, since the AD requires work to be performed in accordance with those documents.

3. Schedule and perform Requirement 1 inspection. Carry out the inspection of the cargo door lower belt frames at the cargo latch receptacles for cracks, in accordance with Part A of the Accomplishment Instructions of the appropriate service bulletin. Note the AD’s compliance timing: Requirement 1 must be done "Within 500 hours time in service after 18 June 1998." Record the inspection findings carefully, as the next required actions depend on whether any cracks are found.

4. If cracks are found, follow Requirement 2 and do not fly until repaired. For any cracked belt frames take the location-specific steps mandated:

   • For belt frames at FS 438.060 and FS 491.060: Repair the belt frame by installing angle P/N 27-22206-009 or 27-22206-010, and fit reinforcement doublers P/N 27-22206-007 and P/N 27-22206-008, in accordance with SRM Section 53-90-20 or ARP 53-30-9701. The AD specifies that the reinforcement doublers "are also needed together with this repair."
   • For belt frames at FS 454.501, FS 455.726, FS 473.392 and FS 474.657: Replace all four belt frames with new-design frames P/N 27-22207-008, P/N 27-22208-005, and P/N 27-22207-007, respectively, in accordance with SRM Section 53-90-20 or ARP 53-30-9701. The AD states that "No reinforcement doublers are needed for these four new design belt frames." Comply with the AD’s timing: the compliance table states that repairs following detection of cracks must be accomplished "Before further flight." Record the work carried out, part numbers used, and reference the specific SRM/ARP procedures followed.

5. If no cracks are found in all six belt frames, follow Requirement 3. Install reinforcement doublers in all six belt frames in accordance with Part B of the Accomplishment Instructions of SB 226-53-007 or SB 227-53-003, as applicable. The compliance timeline is "Within 500 hours time in service after accomplishment of the Requirement 1 inspection." Ensure the reinforcement doublers used match the part numbers set out in the service instructions and the AD where specified.

6. Document compliance and parts fitted. Maintain maintenance entries and records documenting the inspection date, findings, the SB/Part A or Part B steps followed, the SRM or ARP used, part numbers installed, and the sign-off by the authorised maintenance certifier. If relying on prior compliance with cancelled AD/SWSA226/37 for SA226-AT or SA226-TC aircraft, retain evidence demonstrating that compliance, because the AD expressly states that compliance with the cancelled AD constitutes compliance with this AD for those models.

7. Plan for parts and maintenance downtime. The AD’s remedial actions require specific parts (listed part numbers for angles, reinforcement doublers, new-design frames). Operators should source the listed parts and schedule the maintenance intervention. Where cracks are present, repairs must be done before further flight; plan for aircraft downtime accordingly.

8. Maintain traceability to the AD. When completing work, reference AD/SWSA226/84 Amdt 1 in maintenance records so that the inspection and any corrective actions are traceable to the CASA directive.

9. If an alternative method is proposed, pursue CASA approval outside the AD text. The AD itself does not state an alternate-method-of-compliance procedure. If an operator wishes to use an alternative repair or inspection method, they should consult CASA’s procedures for approval of alternative methods of compliance and obtain formal approval prior to relying on an alternative.

10. Monitor for further regulatory guidance. The AD references FAA AD 98-06-25 and a cancelled CASA AD. Operators should check CASA and manufacturer channels for any follow-up guidance, SB revisions, or service letters that might affect the technical or procedural means of complying with this AD.

Following these steps will implement the AD’s requirements as published. The operator bears responsibility for scheduling, financing and executing the inspections, replacement or repair work and for recording compliance evidence.