AD/DHC-1/13 - Flap Return Spring/Flap Check Cable - CANCELLED

The source text embodies a small set of concepts central to ADs and to the specific item at hand. These concepts are present explicitly in the text and should be treated as the document’s operative vocabulary.

• Airworthiness directive identification. The document is an AD and is identified as AD/DHC-1/13. The subject line identifies the affected component: "Flap Return Spring/Flap Check Cable." The entry also carries an administrative tag "10/2008," which in the document is associated with the entry date or issuance period.

• Requirement and cancellation. The entry plainly states "Requirement: CANCELLED." The cancellation is not a suspension or amendment; it is recorded as a cancellation effective 25 September 2008. The background explains why the original requirement existed and why the cancellation is asserted to be appropriate.

• Historical origin. The background says the AD "was raised in 1961 against De Havilland Technical News Sheet (TNS) DCH-1 Aust. No. 3 or Aust. No. 6." That ties the AD to a specific manufacturer service document (TNS) and to a specific historical remedial action.

• Safety failure mode. The original operational safety concern is described in clear mechanical terms: "a number of instances of flaps locking in the down position after failure of the flap return spring." That phrasing identifies both the component (flap return spring) and the symptom (flaps locking in the down position), and implies an associated inspection or modification of the flap check cable or the return spring mechanism.

• Compliance imperative. The background records that "Compliance was required forthwith." That phrase designates the original AD as having immediate mandatory effect on affected aircraft until cancelled.

• Administrative authorship. The cancellation is signed by a CASA delegate, David Villiers, and dated 15 August 2008. The effective cancellation date is given as 25 September 2008. Those entries locate responsibility for the administrative act within the Civil Aviation Safety Authority as represented by its delegate.

These concepts are the only normative building blocks present in the source. The document does not record technical content of the modification, the exact words of the TNS, compliance forms, penalty provisions, or continuing obligations beyond the cancellation statement and the background summary.

The text identifies a specific aircraft type and a subset of those aircraft as the population that was originally subject to the AD and thus affected by the cancellation. The subject line reads "De Havilland DHC-1 (Chipmunk) Series Aeroplanes" and the AD identifier is AD/DHC-1/13 with the caption "Flap Return Spring/Flap Check Cable." The background states that the AD was "raised in 1961 against De Havilland Technical News Sheet (TNS) DCH-1 Aust. No. 3 or Aust. No. 6" and that it required "a modification after a number of instances of flaps locking in the down position after failure of the flap return spring."

From the document itself, the primary affected parties at the time the AD was in force were operators, owners and maintainers of De Havilland DHC-1 (Chipmunk) series aeroplanes that fell within the scope of the relevant TNS (Aust. No. 3 or Aust. No. 6). The AD required those aircraft to be modified "forthwith" when it was originally raised. The cancellation entry asserts that the AD is "no longer required" on the basis that "all affected aircraft would have been modified by now." That phrasing presumes a cohort of "affected aircraft" that have been remediated.

The document does not list registration numbers, serial range, operators, or other identifiers. It does not specify whether limited categories of Chipmunks were excluded. The only explicit nexus in the source between the AD and aircraft is the reference to the De Havilland Technical News Sheet DCH-1 Aust. No. 3 or Aust. No. 6. Anyone seeking to establish whether a particular Chipmunk was covered by the original AD therefore needs to check whether that aircraft was within the scope of those TNS items; the AD text itself does not provide those scope criteria.

Administratively, the issuer is the Civil Aviation Safety Authority (CASA), represented by its delegate David Villiers. Those who would have been required to act while the AD was in force are private parties (owners, operators, maintenance organisations) responsible for the airworthiness of De Havilland DHC-1 aircraft. The cancellation relieves those parties, as of 25 September 2008, from the specific regulatory obligation imposed by AD/DHC-1/13, to the extent the document’s statement that the AD is cancelled is operative.

The source sets out a narrow universe of duties and rights as follows.

Original duty while the AD was in force. The background records that the AD "required a modification" and that "Compliance was required forthwith." That language establishes that, while AD/DHC-1/13 was active, the duty imposed on the owners/operators/maintainers of affected DHC-1 Chipmunks was to implement the specified modification without delay. The document does not reproduce the technical instructions of the modification; instead it references a manufacturer Technical News Sheet (TNS DCH-1 Aust. No. 3 or Aust. No. 6) as the originating document against which the AD was raised. Therefore, the enforceable duty when the AD was live was to carry out whatever modification the AD adopted or mandated, as described in the referenced TNS.

Change in duty on cancellation. The operative change is that the AD obligation has been cancelled as of 25 September 2008. The entry includes the single-line requirement status "CANCELLED" and the explicit sentence, "This AD is cancelled on 25 September 2008." That statement discharges the AD’s compliance duty prospectively from that date according to the instrument’s terms. The document does not specify whether the cancellation has any retrospective effect on compliance records, approvals, or other administrative actions. The text also does not reimpose any new duty.

Rights and entitlements embedded in the text. The document does not articulate rights in the sense of compensatory entitlements, exemptions, or appeals. It does, however, implicitly assign administrative authority to the CASA delegate to cancel the AD, evidenced by the signature block "David Villiers, Delegate of the Civil Aviation Safety Authority." That signature line indicates the decision-maker within the document’s administrative chain.

Ambiguities and silence. The source does not state what documentation or evidence will be accepted to show that an aircraft has been modified, nor does it state whether those modifications must be recorded to maintain an aircraft’s airworthiness, beyond the generic implication that modification was required when the AD was active. The document also does not state any continuing inspection requirement, non-mandatory recommendations, or conditions under which the AD might be reinstated.

In sum, the key duty originally was mandatory prompt modification as per the AD/TNS; the key change documented here is the cancellation of that duty as of 25 September 2008. The source contains no specified ancillary rights or procedural entitlements attached to the cancellation.

The source document explicitly records the administrative act of cancellation but contains no language about penalties, sanctions or enforcement mechanisms tied to AD/DHC-1/13. The entry’s content is limited to identification, background, the cancellation statement, and the signature of a CASA delegate. There is no statutory citation, no mention of penalty provisions, and no description of enforcement action or consequences for non-compliance in the text provided.

What the document does show about enforcement architecture is administrative authorship. It is signed by "David Villiers, Delegate of the Civil Aviation Safety Authority" and dated 15 August 2008. That signature identifies a CASA delegate as the administrative actor responsible for this notice. As a practical matter, in this document CASA is the administering authority that issued and later cancelled the AD; however the source contains no procedural or penal provisions.

Because the source does not set out sanctions, the reader must treat the cancellation text as an administrative record of status change only. The document states that the original AD required modification and that compliance was required "forthwith" when it was issued, which implies that, while that AD was active, some compliance enforcement regime applied; nevertheless, the AD as presented does not itself specify the enforcement instruments or penalties. The cancellation statement likewise contains no enforcement details.

If the user requires authoritative detail on penalties or enforcement mechanisms that would have applied while the AD was in force, or mechanisms for historical enforcement, the present source does not provide them. The text does establish agency ownership of the directive and the effective cancellation date, both of which are relevant to any enforcement analysis, but it supplies no penalty clauses, contravention provisions, or enforcement history in respect of AD/DHC-1/13.

The source explicitly connects the AD to De Havilland Technical News Sheet (TNS) DCH-1 Aust. No. 3 or Aust. No. 6 by stating the AD "was raised in 1961 against De Havilland Technical News Sheet (TNS) DCH-1 Aust. No. 3 or Aust. No. 6." That link is the only cross-reference to other technical or regulatory instruments contained in the text. The AD entry does not reproduce or restate the TNS content; instead it refers to those manufacturer documents as the origin for the required modification.

The document does not reference enabling legislation, CASA regulations, or other statutory provisions that give legal force to an AD, nor does it reference airworthiness standards or manual provisions. The only law-related institutional interaction shown in the source is the involvement of the Civil Aviation Safety Authority through its delegate, implying the AD process operates within CASA’s administrative framework; however, the text does not specify which statutory powers CASA exercised here.

Because the AD was "raised ... against" a manufacturer Technical News Sheet, the interaction mechanism in the source is therefore: manufacturer technical guidance (TNS) as the factual/technical basis, and an AD as the administrative instrument that required modification; the cancellation removes the AD requirement. The document does not clarify whether the TNS itself remains in force as manufacturer guidance, nor whether the TNS continues to carry any legal or contractual implications for maintenance or continued airworthiness; that is outside the explicit scope of the source.

The cancellation statement asserts that "As all affected aircraft would have been modified by now, this AD is no longer required." That is an express administrative assertion about the interface between prior regulatory compulsion and the present state of the aircraft fleet. The text therefore suggests a sequential interaction: manufacturer TNS -> AD requiring modification -> modifications carried out -> AD cancelled. Beyond that sequencing, the document contains no explicit statements about how the cancellation interacts with continuing airworthiness obligations under other regulatory instruments, with continuing manufacturer recommendations, or with any registry or approval requirements.

In short, the source shows a narrow, explicit interaction between this AD and specified De Havilland Technical News Sheets; it does not document interactions with broader statutory instruments, civil liability regimes, or airworthiness certification processes.

The document itself contains a succinct amendment history limited to two temporal nodes and a reference point.

1. Origin: The background states the AD "was raised in 1961 against De Havilland Technical News Sheet (TNS) DCH-1 Aust. No. 3 or Aust. No. 6." That sentence serves as the origin point for AD/DHC-1/13. The source does not supply the exact date in 1961 or the serial text of the original AD as issued at that time. It does, however, attribute the AD’s origin to 1961 and to the manufacturer TNS documents referenced.

2. Cancellation: The AD entry carries the administrative tag "10/2008" and plainly records "Requirement: CANCELLED" with the explanatory sentence "This AD is cancelled on 25 September 2008." The signature block shows the document was signed by David Villiers, "Delegate of the Civil Aviation Safety Authority," and dated 15 August 2008. Those entries establish that the instrument recording the cancellation was executed on 15 August 2008 and records the cancellation as taking effect on 25 September 2008.

The source does not contain intermediate amendments, revisions, superseding ADs, corrigenda, or re-issues. There is no record here of any prior amendment to AD/DHC-1/13 after its original 1961 issuance, and there are no later amendments beyond the 2008 cancellation. The only textual note that reflects change is the final status line "Requirement: CANCELLED."

The document also does not include an explicit transitional or savings provision addressing the legal status of earlier compliance acts taken under the AD; nor does it provide a historical registry of compliance certificates or notations against specific aircraft. The only historical claim beyond the issuance and cancellation dates is the administrative statement that "As all affected aircraft would have been modified by now, this AD is no longer required." That is an asserted state of fleet repair, offered as the factual basis for cancellation.

Therefore, the amendment history contained in the source is limited to: original raising of the AD in 1961 (per the background), and formal cancellation as recorded in the 2008 entry effective 25 September 2008 with signature dated 15 August 2008.

The source contains no litigation history. It does not identify any court proceedings, appeals, judicial reviews, or disputes concerning AD/DHC-1/13, its content, enforcement, validity, or cancellation. The document is purely an administrative note: it identifies the AD, summarises its genesis and purpose, declares its cancellation, and is signed by a CASA delegate.

Because no judicial or tribunal actions are recorded in the text, a reader should treat the absence of litigation references as an absence of recorded litigation within this source. The source itself does not assert that there was or was not litigation, nor does it summarize any legal challenges or adjudications relating to the AD. If litigation history is material for a client or researcher, it is not contained in this document and would require independent verification in judicial databases or administrative records outside the present text.

The cancellation statement and signature imply final administrative action as of the dates shown, but the source does not indicate whether the cancellation was contested, whether it followed any administrative review, or whether any external party objected. The document does not record any outstanding notices, appeals, or proceedings connected to AD/DHC-1/13.

In short, the document provides no litigation history; it records only administrative action. Any inquiry into litigation pertaining to AD/DHC-1/13 must therefore proceed to court records, CASA files, or other archival sources not included in the supplied text.

The source contains a few points of potential misunderstanding or operational subtlety that users must treat as issues to check rather than as settled facts.

• Cancellation date versus signature/publication date. The document is signed and dated 15 August 2008 by the CASA delegate, while the cancellation is recorded as effective "on 25 September 2008." A reader may mistakenly assume the cancellation was effective on the signature date; the text specifies a later effective date. Any operational action that depends on the precise effective date must therefore use 25 September 2008 as stated in the entry, and not 15 August 2008.

• Scope of "affected aircraft." The background states the AD was "raised in 1961 against De Havilland Technical News Sheet (TNS) DCH-1 Aust. No. 3 or Aust. No. 6" and that "Compliance was required forthwith." However the AD entry does not reproduce the scope language from the original AD or the TNS; it therefore does not provide serial numbers, registration ranges, or other scope-limiting criteria. A user should not assume from the statement "all affected aircraft would have been modified by now" that every individual Chipmunk is covered without checking service and maintenance records or the original TNS and AD text.

• Present-tense assertion versus verifiable fact. The cancellation rationale is phrased as an assertion: "As all affected aircraft would have been modified by now, this AD is no longer required." The modal claimant "would have been" is not an absolute certified fact in the text; it is an administrative assertion supporting cancellation. If a regulator or operator needs to verify whether a particular aircraft was modified, the AD text does not supply that verification; maintenance logs or other documentary proof will be necessary.

• Lack of reproduced technical instructions. The AD references De Havilland TNS documents but does not reproduce the technical instructions, parts, or procedures. For historical compliance or maintenance audit purposes, the absence of the technical instructions in the AD entry means an auditor cannot verify what modification was required from this text alone.

• No penalties recorded here. Because the source contains no penalty provisions, a reader cannot rely on this document alone to determine the consequences of non-compliance while the AD was in force, or whether any civil or administrative penalties were applied historically. That information is absent from the source.

• Potential survivals outside the AD. The cancellation removes the AD obligation but the document does not say whether the manufacturer TNS remains an active service document or whether contract terms, operational approvals, or insurance conditions might still require the modification or equivalent measures. The cancellation does not, within this text, extinguish any non-AD legal or contractual obligation that may have existed separately.

• Administrative authorisation not reproduced. The source shows the delegate signed the cancellation, but the text does not include the regulatory provisions empowering the delegate to cancel an AD. Thus, if proof of statutory authority is required, that must be obtained from other regulatory materials.

Each of the above is a "gotcha" because the text either omits specifics or uses phrasing that can be misread. The document’s brevity makes cross-checking with original TNS documents, maintenance records, and CASA administrative files advisable before taking operational or legal positions based solely on this entry.

The document records that AD/DHC-1/13 is cancelled effective 25 September 2008. If compliance is being considered in relation to the AD as it stands in this source, the mechanical compliance position is as follows:

• Prospectively, after the cancellation date stated in the document, there is no active AD obligation under AD/DHC-1/13 recorded here. The entry explicitly states "Requirement: CANCELLED" and "This AD is cancelled on 25 September 2008." Therefore, insofar as compliance with AD/DHC-1/13 is concerned, there is no outstanding AD-imposed modification requirement after that effective cancellation date according to this document.

• Historically, when the AD was in force it required a modification and "Compliance was required forthwith." That means that until cancellation those owners and operators of affected Chipmunks had an immediate duty to carry out the modification described by the AD (which referenced TNS DCH-1 Aust. No. 3 or Aust. No. 6).

Recommended verification steps grounded in the text. Because the cancellation relies on the administrative assertion that "all affected aircraft would have been modified by now," actors should validate that assertion for any aircraft where proof of modification matters (for airworthiness records, sale, transfer, liability, or insurance considerations). The source text does not provide documentary proof of modification for any particular aircraft. Reasonable steps, consistent with the content of the source, include:

• Check maintenance and airworthiness records for the specific aircraft to confirm whether the modification referenced by the originating TNS and mandated by the AD was carried out and properly recorded while the AD was live. The AD text itself does not record those entries.

• Confirm the exact scope of the original AD and the TNS referenced (DCH-1 Aust. No. 3 and Aust. No. 6) where necessary. The AD text links to those TNS numbers; the procedural detail and applicability will be contained in those technical documents that the AD referenced, not in this cancellation entry.

• Note the dates in this instrument: the signature is dated 15 August 2008 and the cancellation is recorded as effective 25 September 2008. Use the effective cancellation date for any regulatory timing questions.

When to re-inspect or remediate. The source gives no continuing inspection or remedial obligation, so any decision to re-inspect, retrofit or otherwise act after cancellation would be a matter of operator judgment, manufacturer recommendation, or other regulatory documents, none of which are included in this text. If a regulator, purchaser or maintenance organisation requires verifiable evidence of modification, the source suggests that evidence will not be contained in the AD cancellation entry but must be sought in maintenance logs, airworthiness records or the original TNS and AD documents.

Administrative follow-up. The source shows the action was taken by a CASA delegate. If an interested party needs formal confirmation beyond the text supplied here , for example a certified cancellation notice, confirmation that an aircraft was removed from AD tracking, or the original TNS instructions , those documents must be requested from CASA or obtained from De Havilland service archives. The AD entry itself provides the AD identifier AD/DHC-1/13 and the TNS references, which are necessary reference points for such requests.

In short, complying with the current state recorded in this document requires no additional action under AD/DHC-1/13 after 25 September 2008, but verifying historical compliance and evidencing it for present purposes will require examination of maintenance records and the original TNS or AD texts, none of which are reproduced in this cancellation entry.