AD/AC/100 - Aileron Inboard and Centre Hinge Support Structure

The directive organises around a short set of tightly specified technical actions tied to a defined fleet. The main concepts present in the text are: applicability, a prescribed inspection method, referenced service bulletins as the procedural standard, conditional corrective action depending on inspection findings, a fixed compliance window, an effective date, and a stated safety rationale.

Applicability: The instrument expressly applies to "All Model 690, 690A, and 690B aircraft." The title header of the document also contains the label "Twin Commander (Gulfstream/Rockwell/ Aerocommander 500, 600 and 700) Series Aeroplanes" and repeats AD/AC/100 in various places; the text therefore presents both a specific model applicability statement and a series-title caption. The formal applicability language is the definitive line in the source.

Inspection method and reference standards: The directive mandates a "visually inspect, using fluorescent dye penetrant method" step and requires inspections be "in accordance with Twin Commander Aircraft LLC Alert Service Bulletin (ASB) 236A and ASB 238, both dated 21 December 2004, as applicable." The text therefore makes compliance conditional on following those ASBs as the procedural standard for inspection and corrective action.

Conditional corrective actions: The Requirement distinguishes two outcomes. If inspections reveal no cracks, the operator must "reinforce the support structures for the inboard and centre aileron hinge fittings that are crack free, in accordance with ASB 236A and 238, as applicable" before further flight. If cracks are evident, the operator must "replace and reinforce the cracked support structures for the inboard and outboard hinge fittings, in accordance with ASB 236A and ASB 238, as applicable" before further flight. The instruction "before further flight" is explicit and applies to both the reinforcement-after-clearance and replace-and-reinforce-if-cracked branches.

Compliance timing: The directive prescribes a compliance window: "Unless already accomplished, within 150 hours time in service or 12 months after 31 August 2006, whichever occurs first." The instrument also states its effective date: "This Airworthiness Directive becomes effective on 31 August 2006."

Safety rationale: The Background explains the risk driver: "The FAA received reports of cracks in the support structures for the inboard and centre aileron hinge fittings on both wings." The text links the inspection and corrective actions to the intended safety outcome: "to detect and correct cracks in the support structures, which could result in aileron failure. Aileron failure could lead to reduced controllability or loss of control of the aircraft."

Cross-reference to FAA: A Note in the Requirement section cites "FAA AD 2006-15-01 Amdt 39-14681." The ASBs named in the requirement are the operational documents the directive requires be followed.

Administrative metadata: The instrument is identified AD/AC/100, dated 9/2006, and signed by a delegate of CASA (David Villiers) on 21 July 2006. The effective date is 31 August 2006. These metadata locate the directive temporally and administratively in the source.

The source text limits substantive coverage to a defined set of aircraft and the actors responsible for their continued fitness for flight. The explicit Applicability entry states: "All Model 690, 690A, and 690B aircraft." That language makes the directive operative for every individual airframe of those models within the jurisdiction of the issuing authority.

The directive does not name individuals or types of persons (for example, operators, owners, maintenance organisations, or certifying staff) in the Applicability block. However, the Requirement directs physical inspection and repair work on the aircraft and sets operative actions "before further flight." Those actions must be completed in respect of the identified aircraft. Practical implementation will fall to the parties that control and maintain the listed aircraft; the source text itself does not allocate responsibilities among owners, operators, maintenance organisations, or certifying engineers using separate phrasing. In the context of the instrument, the duties are tied to the aircraft specified.

Both wings and specific structural elements are identified. The Requirement refers to "the support structures for the inboard and centre aileron hinge fittings on both wings" and (where cracks are found) to "replace and reinforce the cracked support structures for the inboard and outboard hinge fittings." Thus, the work concerns wing hinge-support structures for inboard, centre and,in the replace-if-cracked branch,outboard hinge fittings.

The directive references procedural documents produced by the manufacturer: Twin Commander Aircraft LLC Alert Service Bulletin (ASB) 236A and ASB 238, both dated 21 December 2004. Compliance must be "in accordance with" those ASBs, so recipients of the directive who will perform the inspections and corrective work must access and follow those ASBs.

The Note also references a United States FAA airworthiness directive: "FAA AD 2006-15-01 Amdt 39-14681." That cross-reference means that operators and maintainers who also track FAA publications or operate internationally will find related obligations or guidance in that FAA AD.

In short, the text applies to all Model 690/690A/690B airframes listed. The persons and organisations that will need to act are those who operate, control or maintain those aircraft, and those who implement the ASBs cited. The instrument does not expressly name enforcement authorities beyond showing the delegate signature of the Civil Aviation Safety Authority, nor does it specify fines, remedial orders, or other sanctions in the text provided.

The directive contains a short list of specific duties and no explicit enumeration of rights. The duties are stated in the Requirement and Compliance blocks; the text does not articulate statutory rights, appeal procedures or exemption mechanisms.

Key duties stated in the instrument:

• Inspect: "Visually inspect, using fluorescent dye penetrant method, the support structures for the inboard and centre aileron hinge fittings on both wings, in accordance with Twin Commander Aircraft LLC Alert Service Bulletin (ASB) 236A and ASB 238, both dated 21 December 2004, as applicable." This is a mandatory inspection duty, with a prescribed non-destructive testing technique (fluorescent dye penetrant) and an express requirement to follow the ASBs.
• Reinforce if no cracks: "If no cracks are evident during the above inspection, before further flight, reinforce the support structures for the inboard and centre aileron hinge fittings that are crack free, in accordance with ASB 236A and 238, as applicable." This imposes an affirmative corrective action even where no defect is found.
• Replace and reinforce if cracks are found: "If cracks are evident during the above inspection, before further flight, replace and reinforce the cracked support structures for the inboard and outboard hinge fittings, in accordance with ASB 236A and ASB 238, as applicable." This requires replacement and reinforcement before the aircraft may next fly.
• Timing: "Unless already accomplished, within 150 hours time in service or 12 months after 31 August 2006, whichever occurs first." This sets a maximum delay from the effective date for completing the inspection and any required corrective work.

The directive does not specify rights such as the right to an administrative review, an appeal route, or a process for temporary relief or deferred compliance. It also does not state the allocation of costs. The text does not provide an express mechanism for alternative methods of compliance or for deviations from the ASBs. The only procedural reference is mandatory compliance "in accordance with" the two ASBs named.

The directive also contains a Note referencing FAA AD 2006-15-01 Amdt 39-14681; the Note does not create a duty in its own right within this instrument but points recipients to related FAA material. The Background section explains why the duties are imposed: reports of cracks and the potential for aileron failure which "could lead to reduced controllability or loss of control of the aircraft."

Because the instrument mandates actions "before further flight" in either the reinforcement or replace-and-reinforce scenarios, an immediate operational restriction is implicit in the textual instruction: aircraft identified that have not had the inspection and requisite remedial work completed cannot lawfully undertake subsequent flights until the directive's steps have been satisfied, insofar as the instrument's language is read literally. The text itself does not elaborate on the consequences of non‑compliance.

The source text does not include express penalty provisions or an enforcement regime. There are no fines, administrative sanction formulas, or criminal offence clauses written into the instrument as provided. The document does, however, contain administrative metadata: it is styled AD/AC/100, dated 9/2006, and signed by "David Villiers, Delegate of the Civil Aviation Safety Authority." It also states, "This Airworthiness Directive becomes effective on 31 August 2006."

From the content provided, the only explicit enforcement-related features are:

• the authority identification (a CASA delegate signed the instrument), and
• the language of mandatory action and explicit effective and compliance dates.

The text does not describe:

• any civil or criminal penalties for failure to comply;
• any process for notice, hearing or review if a person disagrees with the directive;
• any formal recordkeeping, audit, or reporting requirements beyond accomplishing the inspection and corrective works "in accordance with" the ASBs; or
• any procedural grace, provisional relief, or approved alternative methods of compliance.

The Note referencing "FAA AD 2006-15-01 Amdt 39-14681" indicates an equivalent or related U.S. airworthiness directive exists, but the instrument does not include any express cross-border enforcement outcomes.

Because the text lacks penalty or procedural enforcement detail, the instrument's immediate public content obliges compliance through clearly worded technical commands and dates, while leaving any formal enforcement mechanisms, sanctions or administrative remedies unarticulated in the material supplied. Parties relying on this instrument will need to consult CASA's administrative practice or other legal sources (not contained in this text) for any enforcement process or sanctions that may be applied in the event of non‑compliance.

The source text references external technical and regulatory instruments but does not state broad interactions with other domestic statutes or regulations. Two types of external references appear in the document:

1. Manufacturer service bulletins as prescriptive technical standards. The Requirement ties the inspection and corrective work directly to Twin Commander Aircraft LLC Alert Service Bulletin (ASB) 236A and ASB 238, both dated 21 December 2004, by requiring that the inspections and actions be "in accordance with" those ASBs. Practically, the ASBs become the operative technical procedure set that recipients must follow for both inspection technique and reinforcement or replacement methodology.

2. A United States airworthiness directive. The Requirement contains a Note: "Note: FAA AD 2006-15-01 Amdt 39-14681." This cross-reference identifies an FAA instrument covering similar or related defects. The source text does not elaborate the legal relationship between the FAA AD and the present instrument; it merely cites the FAA document by number.

The directive does not explicitly refer to, quote, or amend any other Australian legislation, regulation, or instrument in the text provided. It does not identify specific parts of domestic aviation regulations, certification rules, or any statutory instrument it amends. It does not describe how compliance with the ASBs aligns with other maintenance, continuing airworthiness, or operations rules in Australian civil aviation law.

The document’s administrative signature indicates issuance by a delegate of the Civil Aviation Safety Authority, which situates the instrument within CASA’s administrative competence as reflected in the heading and signature. The text does not identify any overlap, inconsistency procedures, or primacy rules vis-à-vis other Australian regulatory instruments.

Therefore, on the face of the text, the directive interacts with two categories of external materials: the manufacturer ASBs that define the technical steps required, and the FAA AD referenced in the Note. The text does not set out how it displaces, supplements, or coordinates with other domestic legal obligations; that coordination is not described within the supplied material.

The instrument supplied contains limited internal amendment-history metadata. The document identifies itself as AD/AC/100 and bears date markers and related document identifiers. The specific items in the source relevant to amendment history are:

• Document identifier and month/year: AD/AC/100, 9/2006 appears on the header line.
• Issue/signature date: signed by David Villiers, Delegate of the Civil Aviation Safety Authority, on 21 July 2006 (the signature line in the source).
• Effective date: "This Airworthiness Directive becomes effective on 31 August 2006."
• Compliance schedule relative to the effective date: the Compliance section prescribes completion "within 150 hours time in service or 12 months after 31 August 2006, whichever occurs first," unless already accomplished.
• References to manufacturer service bulletins that predate the AD: ASB 236A and ASB 238, both dated 21 December 2004, are the procedural standards required by the directive.
• Note referencing a related FAA document: "FAA AD 2006-15-01 Amdt 39-14681."

The text does not include any later amending entries, consolidated versions, or notation of prior versions of AD/AC/100. The only older dates present are the ASBs dated 21 December 2004 and the FAA AD reference number indicating a 2006 FAA action. The document also reproduces AD/AC/100 and the title in multiple places, and repeats the 9/2006 date in several header fragments. Those repeated lines appear to be formatting or layout duplication within the supplied source rather than substantive amendments.

There is no textual history in the material provided that shows corrections, replacements, or later amendments to this particular AD. The instrument as supplied is a single edition with an issue date (21 July 2006) and an effective date (31 August 2006), directing compliance within a defined period after the effective date. The source does not contain any subsequent amendment notation.

The source text contains no record of litigation, disputes or judicial consideration of this instrument. It does not refer to any court decisions, administrative appeals, requests for review, or injunctions in relation to AD/AC/100. No cases are named in the material.

The only external document cited by number is "FAA AD 2006-15-01 Amdt 39-14681," which is referenced as a Note in the Requirement block. The supplied text does not state that the FAA AD has been litigated, nor does it include any judicial history regarding either the FAA AD or ASB 236A/238. The ASBs themselves (Twin Commander Aircraft LLC Alert Service Bulletin 236A and 238, both dated 21 December 2004) are cited as technical instructions; the document does not indicate any legal challenge to those ASBs.

Given the absence of litigation references, the instrument as provided does not document any court or tribunal proceedings affecting its validity, scope or enforcement. The source provides no accounts of contested compliance, enforcement actions, or judicial rulings.

Several features in the source text could create practical ambiguities, operational constraints or administrative risks for recipients. These are drawn directly from the language and structure of the instrument.

1. Title versus applicability mismatch. The top of the source includes the caption "Twin Commander (Gulfstream/Rockwell/ Aerocommander 500, 600 and 700) Series Aeroplanes," whereas the Applicability block plainly states "All Model 690, 690A, and 690B aircraft." Recipients should note that the Applicability paragraph is the operative specification in the text. The repetition of different model-series descriptions in header lines and multiple repeats of AD/AC/100 may cause confusion about which airframes are captured by the directive.

2. "Visually inspect, using fluorescent dye penetrant method." The inspection instruction pairs "visually inspect" with a specific non-destructive test method: fluorescent dye penetrant. Recipients must follow ASB 236A/238 "as applicable" for procedural detail. The directive does not set out step-by-step inspection technique or acceptance/rejection criteria itself; those are in the ASBs named. That means access to the ASBs is necessary to understand exactly how to conduct the mandated inspection and how to interpret results.

3. Reinforcement required even when no cracks are found. The Requirement states that if no cracks are evident, the operator must nevertheless "reinforce the support structures for the inboard and centre aileron hinge fittings that are crack free" before further flight. This is a mandatory preventive reinforcement, not merely a watch-and-wait instruction. It creates immediate action and cost even for airframes with no observed defects.

4. "Replace and reinforce" phrasing expands work if cracks exist. Where cracks are evident, the instruction is to "replace and reinforce the cracked support structures for the inboard and outboard hinge fittings." The introduction of "outboard hinge fittings" in the replace clause differs from the inspection target (which was "inboard and centre aileron hinge fittings") and therefore may lead to broader corrective work than the inspection target suggests. The directive uses both "centre" and "outboard" terminology in different clauses; recipients must ensure they apply the correct scope of replacement and reinforcement to the affected fittings as per ASB guidance.

5. "Before further flight" strictness. Both remedial branches include "before further flight." The directive therefore imposes an operational limitation: until the inspection and any required reinforcement or replacement are completed, the aircraft cannot fly. The source does not provide a grace mechanism or temporary relief in-flight; compliance must be achieved before resuming flight operations.

6. Timing wrinkle. The Compliance window is "within 150 hours time in service or 12 months after 31 August 2006, whichever occurs first." For aircraft with low utilisation, the 12-month calendar limit may be the binding deadline; for high-utilisation aircraft, the 150 hours threshold may be the controlling metric. The "unless already accomplished" clause can relieve aircraft that have completed the work earlier.

7. Absence of explicit enforcement/penalties or alternative compliance provisions. The text does not set out penalties, appeal routes, or approved alternative methods of compliance. The directive therefore places operational requirements on operators without detailing administrative remedies or alternative pathways in the instrument itself.

8. Dependency on outside documents. The technical instructions must be done "in accordance with" ASB 236A and 238. Those ASBs are not reproduced in the text. Operators and maintainers must obtain and follow the ASBs to perform the mandated tasks correctly; the directive does not reproduce the technical content or acceptance standards.

9. Multiple repetitions and formatting noise. The source contains repeated headings and lines (repeated "AD/AC/100", repeated "9/2006", and duplicated title lines). Administrative confusion could arise if operators or maintenance records reference header text rather than the explicit Applicability and Requirement paragraphs.

Each of these points is traceable to the language and structure of the supplied instrument and may affect implementation planning, procurement of parts or services, scheduling of maintenance to avoid grounding, and interpretation of which fittings must be replaced or reinforced.

The source-prescribed steps to achieve compliance are compact and explicit. The following is a direct, staged reading of the Requirement and Compliance language from the instrument, expressed in procedural order as required by the text.

1. Confirm applicability. Check whether the airframe is listed in the Applicability paragraph: "All Model 690, 690A, and 690B aircraft." If the aircraft appears in that list, the directive applies. Note the document’s header also contains other model-series text; rely on the Applicability clause for operative scope.

2. Obtain the referenced technical documents. The Requirement mandates inspections and corrective work be carried out "in accordance with Twin Commander Aircraft LLC Alert Service Bulletin (ASB) 236A and ASB 238, both dated 21 December 2004, as applicable." Obtain copies of ASB 236A and ASB 238 and use them as the procedural standard for inspection, reinforcement and replacement actions.

3. Schedule and perform inspection within the compliance window. Unless already done, carry out the inspection "within 150 hours time in service or 12 months after 31 August 2006, whichever occurs first." The inspection must be a "visual inspect, using fluorescent dye penetrant method" targeting "the support structures for the inboard and centre aileron hinge fittings on both wings." Follow the dye‑penetrant technique and acceptance criteria set out in the ASBs.

4. Interpret inspection results and implement the corresponding remedial branch. The directive requires two alternative paths depending on the inspection outcome:

   • If no cracks are evident: before further flight, reinforce the support structures for the inboard and centre aileron hinge fittings that are crack free, following ASB 236A/238 "as applicable."
   • If cracks are evident: before further flight, replace and reinforce the cracked support structures for the inboard and outboard hinge fittings, following ASB 236A/238 "as applicable."

5. Do not operate the aircraft until remedial action is completed. The directive uses the phrase "before further flight" for both remedial outcomes. Complete the reinforcement or replacement-plus-reinforcement before operating the aircraft again.

6. Document the work performed. While the instrument does not itself specify recordkeeping requirements, the practical implementation to demonstrate compliance will require maintaining maintenance records showing the inspection method (fluorescent dye penetrant), reference to the ASB used (236A or 238), the results of the inspection (no cracks or cracks found), and the reinforcement or replacement work performed and sign-off by appropriate maintenance personnel. The text’s lack of explicit recordkeeping language means recipients should rely on normal maintenance record practices to evidence compliance, referencing the specific directive language and the ASBs named.

7. Consider cross-reference materials. The Requirement contains a Note: "FAA AD 2006-15-01 Amdt 39-14681." Review that FAA AD if operating in jurisdictions where that AD is relevant or if seeking supplementary guidance. The twin ASBs dated 21 December 2004 are the operative service instructions for technical practice.

8. Check whether the work has already been accomplished. The Compliance entry begins "Unless already accomplished," so if the inspection and any appropriate reinforcement/replacement work have already been performed in accordance with ASB 236A/238, no further action is required within the compliance window.

9. Plan parts and maintenance capability. Replacement and reinforcement may require specific structural parts and qualified maintenance capability. The text does not list parts or certifications; the ASBs and the operator’s maintenance organisation will determine required components and competencies.

10. Note dates. The directive "becomes effective on 31 August 2006," and the compliance metrics are relative to that date. For record clarity, maintain dates of inspection and remedial work and cite the AD/AC/100 identifier in maintenance records.

These compliance steps follow directly from the instrument’s Requirement, Compliance, Applicability, and Note language. The document does not provide alternative methods of compliance, explicit exemptions, or penalty language; compliance therefore means completing the inspection and the required reinforcement or replacement in accordance with the cited ASBs and within the specified time window.