AD/EXTRA/10 - Fuselage Structure - Tail Spring Support

The Directive operates around a small set of technical and procedural concepts that determine operator obligations.

• Applicability: The AD specifies models and serial numbers. It applies to Model EA 300/L aircraft serial numbers 01-170, 172, 173, 1171 and 1174-1299; and Model EA 300/200 aircraft serial numbers 01-31 and 1032-1043 (Applicability table). That list is the gating criterion for whether an aircraft is subject to the AD.

• Service Bulletin as normative instrument: Compliance is prescribed by reference to EXTRA Service Bulletin No. SB-300-2-97 Issue B, PART I (inspection procedure) and PART II (modification). The Directive allows the use of “later EASA approved revision” of that Service Bulletin. Thus the Service Bulletin text , and any later EASA-approved revision , becomes the operative technical specification for inspections and modifications (Requirement 1-3; Notes).

• Two-tier action logic: The Directive sets up a conditional logic: inspect (PART I); if crack found, modify (PART II); if no crack, repeat inspections at a maximum interval (50 flight hours) until modification occurs. Modification per PART II terminates the recurring inspection requirement (Requirement 1-3; Note 1).

• Time-based and event-driven compliance triggers: The AD creates both immediate triggers (“Before further flight after 28 July 2009” for initial inspection; “Before further flight” for modification where cracks are found) and a recurring, flight-hours-based inspection interval (every 50 flight hours or at the next scheduled 50-hour inspection after the effective date) (Compliance).

• Reference to EASA AD: The Directive explicitly cross-references EASA AD 2009-0160 (Note 2). Operators are therefore pointed to EASA’s corresponding directive and to EASA approval of later Service Bulletin revisions, making EASA approval a relevant compliance hinge.

• Safety objective: The stated safety mechanism is prevention of tail landing gear separation caused by cracks in the tail spring support mounting base. The manufacturer’s information , that a redesigned support combined with a stiffer tail spring and rough-field use has produced cracking, including after a prior modification , is recited as the operational rationale for mandating inspections and modification (Background).

These concepts determine the compliance path and where costs and operational effects fall: identification of affected fleet members; obtaining and following the specified Service Bulletin (and any later EASA-approved revisions); carrying out and documenting inspections at short intervals; and modifying an airframe where cracking is detected (or electing to modify to eliminate the inspection burden).

The Directive affects three distinct groups by operation of the text.

• Aircraft owners/operators of the listed serial-numbered Extra EA-300 series aeroplanes. The Applicability table lists precise serial numbers for Model EA 300/L and EA 300/200 aircraft. Only aircraft whose serial numbers match the listed ranges are covered by the requirements. Operators must check their airframe serial numbers against the list to determine whether the AD applies (Applicability).

• Maintenance organisations, mechanics and engineers responsible for performing the inspections and modifications specified in EXTRA Service Bulletin No. SB-300-2-97 Issue B (or later EASA-approved revisions). The Directive requires inspections “in accordance with PART I” and modifications “as instructed in PART II”, making performance of those technical tasks the responsibility of maintenance personnel acting for the operator (Requirement 1-2). Where the modification is required before further flight, maintainers must schedule and perform the modification promptly.

• Any person charged with compliance verification and airworthiness oversight for the affected fleet. The AD creates recurrent inspection obligations (every 50 flight hours until modification) and a formal termination condition for those inspections (modification under PART II). That requires record-keeping and oversight by operators and maintenance record custodians.

The Directive does not name other affected parties in the text , for example, it does not identify suppliers of parts, nor does it create obligations for third-party regulators outside the issuing authority beyond the reference to EASA approvals and EASA AD 2009-0160 (Note 2). The Directive’s operational effect is concentrated on operators of the listed serial numbers and the maintenance resources they must employ to implement the inspection and modification instructions. The Directive also implicitly affects flight operations, because the initial inspection and any required modification are tied to “before further flight” prescriptions, and recurring inspections are tied to flight hours (Compliance).

Who pays and who bears operational disruption: the text requires actions by operators and maintainers; therefore the direct costs (labour for inspections, parts and labour for modification, and any aircraft downtime) fall on the aircraft owner/operator and the maintenance provider they engage. The document does not allocate or quantify costs, nor does it set out any compensation or support mechanism.

The Directive imposes specific duties and creates a limited set of operator entitlements by the terms of the text.

Duties

• Identify applicability: Operators whose aircraft serial numbers fall within the listed ranges must treat the AD as applying and proceed to compliance steps (Applicability).

• Initial inspection: For affected aircraft, the duty is to “Inspect the tail spring support in accordance with PART I of EXTRA Service Bulletin No. SB-300-2-97 Issue B, or later EASA approved revision” (Requirement 1). The Compliance section links this inspection to an immediate pre-flight obligation: the initial inspection must be done “Before further flight after 28 July 2009.”

• Modification if cracks detected: If any crack is detected during inspection, the operator must “modify the tail spring support structure as instructed in PART II” of the Service Bulletin (Requirement 2). The Compliance timing requires this modification to be completed “Before further flight” (Compliance).

• Recurring inspections: If no crack is found, the operator must repeat inspections “in accordance with PART I” within 50 flight hours or at the next scheduled 50-hour inspection after 28 July 2009, whichever comes first, and at intervals not to exceed 50 flight hours until the PART II modification is completed (Requirement 3; Compliance).

• Termination of recurring inspections upon modification: Completing the PART II modification terminates the requirement for the recurring 50-hour inspections (Note 1).

Rights or entitlements (as expressed or implied in the AD text)

• Use of later EASA-approved revisions: The AD allows the use of “later EASA approved revision[s]” of the Service Bulletin for inspection and modification instructions (Requirements and Notes). That gives operators the entitlement to rely on an updated, EASA-approved revision rather than strictly Issue B.

• Defined methods to terminate recurring obligations: The Directive explicitly provides a path to stop the recurring inspection burden, namely by undertaking the PART II modification (Note 1). That is an operational right , once modification is completed, recurring inspections per Requirement 3 are no longer required by this AD.

What the Directive does not say (limits to duties/rights in the text)

• No alternative means of compliance (AMOC) or exemption procedure is described in the text. The Directive does not provide an in-Directive mechanism to accept an alternative inspection technique or modification outside the referenced Service Bulletin.

• No specific record-keeping format, evidence of compliance, or administrative notification requirement is set out in the AD text itself.

Mechanically, therefore, duties are precise and technically bounded: inspect per PART I, modify per PART II if cracks found, repeat inspections until modification, and rely on EASA-approved revisions where appropriate. The Directive ties duties to flight status by using “before further flight” and a measurable recurring interval (50 flight hours), which creates operational constraints for operators.

The Directive itself, as reproduced, does not set out statutory penalties, fines, or the enforcement mechanisms to be used in the event of non-compliance. The published text specifies the requirements, the compliance timelines and the effective date, but it does not include express enforcement provisions or sanctions within the body of this document. The directive is signed by a Delegate of the Civil Aviation Safety Authority and states it "becomes effective on 28 July 2009" (Compliance; signature block). The only enforcement-related operational mechanism contained in the text is the prescriptive linkage of certain actions to flight status: initial inspections and any required modification are mandated to occur “before further flight” (Compliance). That linkage creates an operational constraint: unless inspections or modifications take place as required, the directives’ own terms would permit no further flight of the affected aeroplane insofar as compliance is concerned.

Practical enforcement implications arising from the Directive’s content (textually grounded)

• Immediate operational impediment: Requiring initial inspection “before further flight after 28 July 2009” and requiring modification “before further flight” if cracks are found effectively prevents the operator from lawfully flying the aircraft without performing the specified tasks, assuming the regulatory regime governing airworthiness requires compliance with such ADs (the Directive itself does not state that consequence; it sets the before-flight requirement).

• Recurrence obligation as ongoing compliance measure: The requirement to inspect at intervals not to exceed 50 flight hours until modification is completed creates an ongoing operational compliance obligation that an oversight authority or maintenance record audit could check.

What is not in the text

• The AD does not enumerate administrative procedures for CASA inspections, show-cause notices, suspension or revocation of certificates, or civil or criminal penalties. Absent such provisions in the Directive text, the publication does not itself define enforcement pathways or penalties. Any enforcement action, fines or administrative sanctions would need to be traced to other instruments or the general regulatory framework that governs airworthiness directives and operator obligations , such instruments are not included in the text supplied.

Operators and their advisers should therefore treat the Directive’s “before further flight” and recurring inspection prescriptions as mandatory technical obligations under the AD, and should be prepared for operational interruption and documentation demands. The Directive’s silence on penalties means that questions about sanctioning and enforcement procedures lie outside this text and would require reference to the broader regulatory framework not reproduced here.

The Directive expressly cross-references two external instruments: EXTRA Service Bulletin No. SB-300-2-97 (Issue B) with allowance for “later EASA approved revision[s]” and EASA AD 2009-0160 (Note 2). Those cross-references create a direct interaction with documents that are external to this AD.

• Service Bulletin dependency: The AD makes the Service Bulletin the normative source for methods and technical detail. Compliance is defined as performing inspections “in accordance with PART I” and modifications per “PART II” of SB-300-2-97 Issue B, or later EASA-approved revisions (Requirement 1-3). This means that the technical content of the Service Bulletin (for example, inspection locations, non-destructive testing procedures, modification drawings, parts lists, torque settings) governs how the AD’s obligations are to be implemented. In effect, the AD delegates detailed technical standards to the Service Bulletin, and allows later EASA-approved revisions of that Bulletin to substitute for the Issue B text.

• Link to EASA AD: The Directive’s Note 2 states that “EASA AD 2009-0160 refers.” That implies that EASA has issued a corresponding AD and that EASA approvals of Service Bulletin revisions are relevant. The Directive therefore interacts with EASA processes: any later revision to SB-300-2-97 must be EASA-approved for it to be used under this AD, and operators are signposted to EASA AD 2009-0160 for further or corresponding direction.

• No other statutory cross-references present: The printed AD does not reference Australian Civil Aviation regulations, the legal framework for airworthiness directives, or other national statutory instruments. It also does not reference exemptions, alternative means of compliance, or appeal mechanisms. The only institutional signature is that of a CASA Delegate, which establishes the issuing authority for this document, but the AD text as provided does not set out the mechanics of how it sits within broader law.

Practical implications of the interactions stated

• Reliance on EASA approval: By permitting “later EASA approved revision[s]” the AD requires operators to ensure that any later Service Bulletin revision they use is EASA-approved, not merely published by the manufacturer. This creates a compliance dependency on EASA’s approval process and on access to EASA AD 2009-0160 to confirm approvals.

• Potential for multiple applicable documents: Where the Service Bulletin is revised and EASA issues related approval or amendments, operators must track both the Extra Service Bulletin revisions and EASA AD publications to ensure they are using an approved revision. The AD itself does not list or reproduce the technical content of SB-300-2-97; operators must obtain and follow the Service Bulletin.

• Termination mechanics: Because the AD states that modification per PART II terminates the recurring inspection requirement, the applicable modification standard is defined by the Service Bulletin revision in force and EASA approval status. That means the interplay determines when an operator can stop recurring inspections.

Where the AD is silent, interactions with other laws and administrative practices (for example, inspection of maintenance records by regulators, enforcement actions, or certification consequences for non-compliance) are not detailed in the text and would require reference to the broader regulatory framework outside this document.

The document as provided contains a single issuance and effective date. The AD is dated and signed by a Delegate of the Civil Aviation Safety Authority (David Villiers) on 23 July 2009, and states that it becomes effective on 28 July 2009 (signature block; Compliance). The title block identifies the AD as AD/EXTRA/10, Fuselage Structure - Tail Spring Support, 10/2009 DM.

What the text records about prior or later amendments

• The AD allows the use of “later EASA approved revision[s]” of Service Bulletin No. SB-300-2-97 (Requirement and Notes). That phrase anticipates future technical revisions to the Service Bulletin that are approved by EASA and which operators may use to comply with this Directive. It does not itself constitute an amendment to the AD text, but it creates a procedure for integrating later EASA-approved technical revisions into compliance.

• The AD notes that “Cracks have also been reported on aircraft already compliant with PART II of SB-300-2-97 Issue A” (Background). That historical observation indicates prior Service Bulletin iterations existed (Issue A) and that an aircraft previously modified under Issue A experienced cracking. The AD therefore responds to field experience post-Issue A and prescribes inspection and modification per Issue B or later EASA-approved revisions.

What the AD does not include

• The document does not include any record of amendments, supersessions, or revocations of earlier ADs beyond the contextual reference to Issue A of the Service Bulletin. It does not state that it supersedes a prior AD, nor does it list amendment dates subsequent to the effective date. The only temporal markers in the text are the signing date (23 July 2009) and the effective date (28 July 2009).

Operational practice

• To determine whether later amendments or superseding directives exist beyond this document, an operator would need to check the issuing authority’s AD database, the manufacturer’s service bulletin release history, and EASA’s AD records. Those sources are not reproduced in this text; the AD itself provides only the single issuance and an invitation to use later EASA-approved revisions of the Service Bulletin.

The AD text contains no litigation history. It does not identify any judicial decisions, appeals, administrative challenges, or disputes arising from this Directive. There are no case names, references to appeals, or notes of legal proceedings in the document.

What the absence of litigation history in the AD means for users

• The document does not record that the Directive was the subject of any legal challenge up to the date of issue. It does not provide any precedent or authoritative litigation context to inform how courts, tribunals or other decision-makers have interpreted the AD’s obligations or any associated disputes.

• Any legal questions about the AD’s interpretation, enforcement, or validity would therefore need to be researched outside the text , by checking court records, tribunal determinations, or regulatory appeal decisions , because nothing in this AD records or purports to summarise litigation outcomes or procedural objections.

Practical consequence

• Advisors reviewing the AD for legal risk or potential disputes must treat the Directive solely as a prescriptive airworthiness instrument with the content in the text. If concerns exist about enforceability, applicability to a particular serial-numbered aircraft, or the sufficiency of the Service Bulletin instructions as a means of compliance, those are matters for operational resolution or for legal challenge under broader administrative law processes outside the AD. The AD contains no internal litigation or appeal roadmap.

This section highlights textually grounded pitfalls, ambiguities and operationally consequential details drawn from the AD text that can cause non-compliance or operational disruption if overlooked.

• Serial-number precision and gaps: The Applicability table lists specific serial number ranges for two models. Operators must match their aircraft serial numbers exactly against the lists. The ranges are non-contiguous in places (for example, 01 through 170, 172, 173, 1171, 1174 through 1299 for EA 300/L). Small transcription errors or misunderstandings about how serial numbers are presented on logbooks or plates could lead an operator to mis-assess applicability. The AD itself provides the only applicability list in the text.

• Reliance on an externally authored Service Bulletin: All inspection and modification methods are specified by reference to PART I and PART II of SB-300-2-97 Issue B or later EASA-approved revisions. The AD does not reproduce the Service Bulletin. Operators must obtain the correct Service Bulletin and ensure they use an Issue B copy or an EASA-approved later revision. Using an unapproved “later” revision or a manufacturer-only revision that lacks EASA approval would not meet the AD’s textually stated option.

• EASA approval requirement for later revisions: The AD permits “later EASA approved revision[s]” only. If the manufacturer publishes a technical change that has not been EASA-approved, the AD does not authorise use of that change. Operators must check EASA approval status, not merely the publisher’s change list.

• Interpretation of “before further flight”: The Compliance section requires certain actions “Before further flight” (initial inspection if flight occurs after 28 July 2009; and modification if cracks are found). That phrase is operationally strict in the Directive’s wording but not further defined in the text. Practically, operators must not fly again without completing the specified step, but the AD does not supply a tolerance period, an allowance for ferry flights, or an administrative exemption. If parts, tooling or a qualified maintenance resource are unavailable, the aircraft could be grounded.

• Timing for the recurring inspection: Requirement 3 is to be done “Within 50 flight hours or at the next scheduled 50-hour inspection after 28 July 2009, whichever occurs first,” and then “at intervals not to exceed 50 flight hours; until modification ... as instructed in PART II.” Operators must therefore reconcile scheduled maintenance intervals with actual flight-hour accrual. For aircraft that fly infrequently, the “within 50 flight hours” trigger could be a long calendar period; for high-utilisation aircraft it may be weeks. Misreading the “or at the next scheduled 50-hour inspection” phrasing could lead to an unnecessary delay or premature inspection.

• Termination of inspections only by PART II modification: The AD states that PART II modification terminates the recurring inspections (Note 1). If an operator performs an alternative repair or enhancement not described in PART II, the AD provides no textual basis for terminating inspections. Absent any alternate approval pathway in the AD, the operator remains bound to recurring inspections unless and until the PART II modification (or an EASA-approved alternative reflected in the Service Bulletin) is completed.

• Prior compliance under Issue A not necessarily sufficient: The Background explicitly notes cracks have been reported on aircraft already compliant with PART II of SB-300-2-97 Issue A. The AD therefore signals that earlier modifications under Issue A did not eliminate cracking risk. Operators who migrated their aircraft under Issue A might still be subject to the AD’s inspection obligations unless they complete PART II per Issue B or a later EASA-approved revision. Failure to appreciate this could lead to a false sense of security.

• No express record-keeping or reporting requirement in the text: The AD does not state how inspections or modifications are to be documented or reported. Best practice would be to document inspection results and modification completion; the AD text, however, provides no format or submission destination. This silence means operators must rely on prevailing maintenance and regulatory record practices outside the AD.

• Cross-reference to EASA AD: The AD notes that EASA AD 2009-0160 refers. Operators must obtain and read the EASA AD to confirm any cross-jurisdictional compliance expectations, but the AD does not reproduce EASA AD content. Failure to consult the EASA document may overlook relevant further guidance or differences.

These “gotchas” arise directly from how the AD frames applicability, the way it delegates technical content to a Service Bulletin, the timing language used for inspections and modifications, and the AD’s silences on record-keeping, alternative compliance and enforcement mechanics.

The AD prescribes a narrow and actionable path to compliance. The following steps are a practical checklist, strictly derived from the AD text, for operators and maintenance personnel to follow.

1. Confirm applicability

   • Check the aircraft model and serial number against the AD’s Applicability list: Model EA 300/L serial numbers 01-170, 172, 173, 1171, 1174-1299; Model EA 300/200 serial numbers 01-31, 1032-1043. If the aircraft serial number appears in those ranges, the AD applies (Applicability).

2. Obtain the referenced Service Bulletin and any relevant EASA AD

   • Acquire EXTRA Service Bulletin No. SB-300-2-97 Issue B, specifically PART I (inspection procedures) and PART II (modification instructions).
   • Determine whether any “later EASA approved revision” of SB-300-2-97 exists and is EASA-approved. If a later EASA-approved revision is to be used, ensure the EASA approval is verified; the AD allows later EASA-approved revisions as compliance instruments (Requirement 1-3; Note 2).
   • Obtain and review EASA AD 2009-0160, which the AD references (Note 2).

3. Perform the initial inspection as required

   • Carry out the inspection of the tail spring support in accordance with PART I of SB-300-2-97 Issue B or the later EASA-approved revision (Requirement 1).
   • Timing: initial inspection must be done “Before further flight after 28 July 2009” (Compliance). If the aircraft has not flown since that effective date, the inspection must occur prior to the next flight.

4. If cracks are found, modify immediately

   • If any crack is detected during inspection, implement the PART II modification instructions from SB-300-2-97 Issue B or the EASA-approved later revision (Requirement 2).
   • Timing: the Directive requires the modification to be completed “Before further flight” (Compliance). Schedule and perform the modification without returning the aircraft to flight until the modification is complete.

5. If no cracks are found, implement recurring inspections

   • If inspection reveals no cracking, schedule recurring inspections “in accordance with PART I” of the Service Bulletin (Requirement 3).
   • Timing: accomplish the first recurrence “Within 50 flight hours or at the next scheduled 50-hour inspection after 28 July 2009, whichever occurs first,” and thereafter at intervals not to exceed 50 flight hours until the PART II modification is completed (Compliance).

6. Use modification to terminate recurring inspections

   • Completing the PART II modification as instructed terminates the recurring 50-flight-hour inspection requirement under this AD (Note 1). If electing to eliminate the recurring inspections, ensure the Part II modification used is the version set out in the SB Issue B or a later EASA-approved revision that the AD authorises.

7. Document all actions

   • While the AD text does not specify record-keeping procedures, document the inspection findings, dates, flight hours at inspection, and any modifications carried out. Maintain copies of the specific Service Bulletin revision used and EASA approval documentation where applicable because the AD’s compliance condition depends on using Issue B or an EASA-approved later revision.

8. Plan for operational impact

   • Because the AD ties work to “before further flight,” be prepared for potential grounding of the aircraft while awaiting inspections, parts, or qualified maintenance personnel. If cracks are found, modification must be completed before the aircraft flies again.

9. Keep track of Service Bulletin and EASA updates

   • Monitor the manufacturer for Service Bulletin revisions and EASA for approvals and related ADs. The AD allows later EASA-approved revisions to be used for compliance; therefore, an operator may be able to rely on a later EASA-approved revision if and when it is issued.

10. Seek clarification if needed

• The AD text does not provide an alternative compliance pathway or detail enforcement procedures. If an operator considers an alternative inspection technique or modification not described in the authorised Service Bulletin, seek formal confirmation or approval through the relevant airworthiness authority or via consultation with the manufacturer and EASA. The AD itself does not include an AMOC procedure.

Following these steps will satisfy the explicit prescriptions contained in the AD: initial inspection per PART I before next flight after 28 July 2009, immediate modification before flight if cracks are found per PART II, and recurring 50-flight-hour inspections until modification is completed. All procedures must be performed in accordance with the Service Bulletin revision that is either Issue B or later with EASA approval, in line with the Directive’s text.