AD/A320/160 Amdt 1 - Cargo Compartment Heating Temperature Sensor

This Airworthiness Directive amendment (AD/A320/160 Amdt 1) requires a modification to the aft cargo compartment heating temperature sensor installation on certain Airbus A319, A320 and A321 series aeroplanes. The AD instructs operators to carry out the modification in accordance with the instructions given in Airbus Service Bulletin A320-21-1141, or a later revision of that SB provided it has been approved by the Direction Générale de l’Aviation Civile (DGAC) of France. The AD sets a compliance deadline of "Before 31 May 2007" and states the amendment became effective on 1 September 2005. It was issued by the Civil Aviation Safety Authority (CASA) delegate, David Villiers, on 22 July 2005.

Mechanically, the instrument changes the status of the sensor modification from recommended or advisory to mandatory for the aircraft to which the AD applies, unless the aircraft already has specific Airbus production modifications or service bulletin embodied during production or in service. The Directive explicitly excludes aeroplanes that, during production, incorporated Airbus modification 24486 (A319), 20084 (A320) or 22596 (A321), or that have embodied certain Airbus service bulletins whilst in service (A320-21-1140 for A319, A320-21-1048 for A320). The AD refers to a related DGAC AD (F-2004-123 R1) and notes EASA approval number 2005-5892 for that DGAC AD.

The stated safety rationale in the AD is that, during a fire containment capability evaluation of the cargo compartment of an A319, the halon extinguishing agent concentration fell below the required level because the rate of air renewal in the compartment was too high. An investigation identified two air leaks; one from the forward and aft cargo door water drain valves, and one from the aft cargo compartment temperature sensor installation. The AD makes the modification of the temperature sensor mandatory to prevent the second of those leaks. The amendment extends the earlier compliance date to 31 May 2007; the original AD first became effective on 30 September 2004.

This instrument therefore converts a manufacturer-recommended modification procedure into a mandatory modification for a specified set of airframes, unless those airframes already incorporate certain Airbus production modifications or earlier service bulletin embodiments. The operative instruction is the embodiment of SB A320-21-1141 (or later DGAC-approved revision) on or before the stated compliance date.

Applicability and exclusions

• The AD applies to A319, A320 and A321 series aeroplanes specified in the Applicability table, with explicit exclusions for aeroplanes that already have certain Airbus production modifications incorporated or particular Airbus service bulletins embodied in service. The AD text states: "applicability: A319, A320 and A321 series aeroplanes as follows, except those aeroplanes with Airbus modification 32616 incorporated during production or Airbus Service Bulletin (SB) A320-21-1141 embodied whilst in service" and then lists the specific production modifications and SBs that exempt certain subtypes (A319: modification 24486 or SB A320-21-1140; A320: modification 20084 or SB A320-21-1048; A321: modification 22596). The exclusion language is specific: incorporation during production or embodiment whilst in service.

Mandated technical action

• The core technical obligation is: "Modify the temperature sensor of the aft cargo compartment heating system in accordance with the instructions given in SB A320-21-1141 or later revision approved by the DGAC." The AD does not provide technical detail itself; it delegates the specific modification instructions to the Airbus service bulletin referenced, and it permits later revisions only if approved by DGAC.

Compliance timing and amendment effect

• The AD sets the compliance deadline "Before 31 May 2007." The amendment text states it "extends the compliance from 31 October 2006 to 31 May 2007," and that "This Amendment becomes effective on 1 September 2005." The original Directive became effective on 30 September 2004; the amendment therefore alters the compliance timetable while preserving the underlying requirement.

Safety finding that triggered the AD

• The AD records the DGAC's finding that, during a fire containment capability evaluation of an A319 cargo compartment, halon concentration decreased below the required concentration due to an excessive rate of air renewal. The investigation isolated two leak sources: water drain valves and the aft cargo compartment temperature sensor installation. The AD identifies the sensor leak as the specific subject of the mandatory modification.

Regulatory references and approvals

• The AD explicitly cross-references DGAC AD F-2004-123 R1 and notes EASA approval 2005-5892 for that DGAC AD. It also conditions acceptance of later revisions of the Airbus SB on DGAC approval.

Operators and owners of the identified Airbus airframes

• The immediate subjects are operators and owners of Airbus A319, A320 and A321 series aeroplanes that fall within the AD's applicability as printed. The AD lists the airframes and then carves out those that already have specified production modifications or SBs embodied. The text requires modification "Before 31 May 2007," which imposes a duty on whoever is responsible for the aircraft's continued airworthiness to ensure the modification is performed by that date.

Maintenance organisations and technicians

• Because the AD requires embodiment "in accordance with the instructions given in SB A320-21-1141 or later revision approved by the DGAC," maintenance organisations that perform the modification must have access to, and be able to implement, the detailed procedures in that SB. The AD does not itself detail the tasks or tooling, so performing organisations must follow the SB and any regulatory approvals referenced.

Aircraft registrars and compliance auditors

• Airworthiness authorities, compliance auditors and continuing airworthiness management organisations who maintain compliance records will be affected in that they must confirm that aircraft subject to the AD have had the SB embodied or otherwise are excluded by virtue of the listed modifications or prior SB embodiment. The applicability language requires checking production modification incorporation and in-service SB embodiment records.

Pilot/operators with aircraft pending sale or lease

• For aircraft transfers during the compliance window, sellers, lessors and lessees must determine whether the aircraft are compliant, exempt, or require the modification prior to transfer; the AD's exclusions hinge on physical modifications or SB embodiment having been completed. The AD creates a discrete continuing airworthiness obligation that affects the transferability and required maintenance prior to operation.

Regulatory bodies and foreign authorities

• The AD references DGAC and EASA approvals and is itself a CASA instrument. DGAC is the foreign authority from which the underlying safety finding and SB approvals derive; EASA approval is referenced for DGAC AD F-2004-123 R1. The AD affects how CASA communicates and recognises DGAC-approved SB revisions.

Supply chain and spare parts providers

• The requirement to modify per the Airbus SB will create demand for the parts and kits specified in SB A320-21-1141. Suppliers of the sensor or sensor installation hardware, and logistics planners for scheduled maintenance, will be indirectly affected by the AD insofar as operators require parts to meet the compliance deadline.

Primary duty to modify

• The principal duty created by the AD is explicit: "Modify the temperature sensor of the aft cargo compartment heating system in accordance with the instructions given in SB A320-21-1141 or later revision approved by the DGAC." This is a mandatory technical obligation for each aircraft to which the AD applies, to be completed before the specified compliance date ("Before 31 May 2007").

Duty to determine applicability

• Operators and maintenance managers must determine whether each aeroplane is caught by the AD or excluded by the listed production modifications or prior SB embodiment. The AD’s applicability table lists the exclusions by modification number and SB number; accurate records and verification are therefore required before deciding whether to implement the SB.

Duty to use approved SB revisions

• The AD requires embodiment in accordance with SB A320-21-1141 or a later revision only if that later revision has been "approved by the DGAC." This creates a duty to ensure that any alternative or updated SB revision relied upon has the necessary DGAC approval before implementation.

Timing duty

• The AD prescribes a compliance timeframe, "Before 31 May 2007." This fixes a temporal obligation; aircraft operators who have not completed the modification by that date will not have complied with the AD.

Record-keeping and proof of compliance

• While the AD does not specify precise record-keeping language, the nature of airworthiness directives implies that operators must be able to demonstrate compliance. The AD’s requirements to modify per the SB and to observe the DGAC approval condition will necessitate maintenance records that show SB embodiment or the presence of the listed production modifications.

Rights or exemptions

• The AD supplies explicit exemptions in the Applicability table: aircraft with specified Airbus modifications incorporated during production or certain SBs embodied in service are not required to perform the SB A320-21-1141 modification because the equivalence has been recognised by the AD’s applicability language. The AD also allows reliance on later revisions of the referenced SB, but only if approved by DGAC; this provides some flexibility while requiring confirmation of foreign authority approval.

Obligation to follow an external document

No penalties specified in the AD text

• The AD text supplied does not set out penalties, fines or explicit enforcement mechanisms. The document records the requirement and the compliance date, and is signed by the CASA delegate, but it contains no cross-reference to statutory penalty provisions or enforcement procedures within the AD itself.

Enforcement implied by mandatory nature

• The AD converts a manufacturer instruction into a mandatory requirement for the applicability population, with a compliance deadline. Although the AD does not specify enforcement measures, the requirement itself implies that the responsible regulatory authority expects compliance. The AD provides no operational or administrative guidance about how CASA will monitor or enforce compliance, nor does it indicate remedial steps, exemptions, or appeals procedures within the AD text.

Role of DGAC and EASA approvals

• The AD references DGAC AD F-2004-123 R1 and notes EASA approval 2005-5892 for that DGAC AD. While this cross-reference situates the SB and its approvals within an international approval framework, the AD does not state how DGAC or EASA approvals interact with CASA's enforcement in Australian territory; it simply requires SB revisions to be DGAC-approved for them to be acceptable under the AD.

Practical enforcement implications

• Because the AD imposes an explicit compliance date ("Before 31 May 2007") and a specific action (embodiment of the SB or evidence of prior applicable modifications), enforcement in practice will likely require maintenance records demonstrating embodiment or exemption. The AD itself does not specify how CASA will verify compliance, how often, or what evidence will be required.

Audit and oversight considerations

• The absence of enforcement detail in the AD means that compliance checking will rely on existing CASA processes for continuing airworthiness oversight and record audit. The AD provides the mandatory technical trigger; the mechanisms for verification and potential consequences for non-compliance are not stated here.

No penalties or enforcement procedures in-source

• In summary, the AD does not state civil or criminal penalties or administrative processes; it sets the mandatory technical requirement and deadline, but leaves enforcement and penalty regimes outside the text of the AD as presented.

Cross-reference to foreign airworthiness actions

• The AD explicitly refers to DGAC AD F-2004-123 R1 and notes that EASA approval 2005-5892 applies to that DGAC AD. The interplay is therefore multi-jurisdictional: the technical instructions in the Airbus SB are conditioned on DGAC approval, and CASA’s AD references those foreign authority actions. The AD thus recognises the role of DGAC and EASA in approving the technical content of the SB and its revisions.

Delegation of technical detail to manufacturer SB

• The AD does not contain the technical modification instructions itself; it operationalises Airbus Service Bulletin A320-21-1141 by making it mandatory for affected aircraft. This pattern is common in continuing airworthiness regulation: the regulator mandates a manufacturer’s service bulletin or an AD from another authority. The AD therefore interacts with the contractual relationship between owners/operators and manufacturers: the SB remains the source of technical detail, while CASA’s AD makes it mandatory for Australian applicability.

Interaction with production modification records

• The AD’s applicability/exclusion regime depends on production modifications incorporated during manufacture (modification numbers such as 24486, 20084, 22596, 32616) and on SBs embodied whilst in service. That means maintenance recordkeeping regimes and production history run sheets will be relevant to determine regulatory obligations. The AD thus interacts with the administrative law of aircraft recordkeeping and continuing airworthiness documentation.

No statutory enforcement text included

• The AD does not itself cite enabling legislation within its text, nor does it specify enforcement procedures or penalties. It therefore relies on the existing regulatory framework and CASA’s general powers for any enforcement action, but the AD does not describe those powers or their procedural mechanics. Any interaction with other laws (administrative or criminal penalty regimes) is outside the AD text presented here.

International acceptance of approvals

• By conditioning the acceptance of later SB revisions on DGAC approval and by noting EASA approval of the DGAC AD, the instrument creates a path for international technical acceptance: if DGAC (and EASA via approval) accepts a revision, CASA’s AD accepts that DGAC-approved revision for compliance purposes. This creates an interaction whereby foreign authority approvals are a prerequisite to the domestic acceptability of SB revisions.

Original AD issue

• The AD notes that the "original issue of this Directive became effective on 30 September 2004." That original directive mandated modification of the temperature sensor to prevent the identified sensor-related air leak.

This amendment details

• The document before you is Amendment 1 of AD/A320/160. The amendment "extends the compliance from 31 October 2006 to 31 May 2007." The amendment itself "becomes effective on 1 September 2005," and the AD record is dated 22 July 2005 (signed by the CASA delegate).

Reason for amendment

• The amendment extends the compliance date; the AD text states: "This Amendment extends the compliance from 31 October 2006 to 31 May 2007." The AD does not give any further administrative reasons for the extension within its text.

Relationship to DGAC and EASA approvals

• The AD includes a note: "DGAC AD F-2004-123 R1(EASA Approval 2005-5892) refers." That ties the historical chain of regulatory action to a DGAC AD, which itself had EASA approval. The AD indicates that the DGAC action is the origin of the safety finding and of the service bulletin's instructional basis.

Prior actions identified in Background

• The Background section recounts that, during testing, a halon concentration fell below the required level in a containment evaluation, and an investigation identified two leak sources, one of which is the aft cargo compartment temperature sensor installation. The original issue of the Directive mandated the temperature sensor modification to prevent that leak. The amendment keeps that mandate but extends the compliance timeframe.

No further amendments recorded in the supplied text

• The supplied text lists only the original issue and this Amendment 1. No other amendments, revocations, or superseding actions appear within the provided document. The AD instructs compliance with SB A320-21-1141 "or later revision approved by the DGAC," indicating that future approved SB revisions may be acceptable for compliance, but no further CASA amendments are recorded in the supplied material.

Dates and timeline summary

• Original AD effective: 30 September 2004 (original issue).
• Amendment 1: effective 1 September 2005; AD dated 22 July 2005 signed by CASA delegate.
• Compliance date as amended: Before 31 May 2007 (extension from 31 October 2006).

No litigation or case law referenced in the AD

• The text of AD/A320/160 Amdt 1 contains no references to litigation, judicial review, court orders, or legal challenges. It records only the regulatory action, the background investigative findings, and the amendment to the compliance date.

No reported appeals, revocations or stays in the supplied text

• The AD does not indicate that it has been subject to appeals, stays, or revocation proceedings. It does reference DGAC AD F-2004-123 R1 and EASA approval 2005-5892, but those are regulatory approvals, not litigation.

Implication for the reader

• Because the supplied document contains no litigation history, researchers and practitioners should not assume existence of court decisions affecting this AD from this text alone. Any litigation or disputes arising from enforcement or compliance would be outside the supplied document and are not recorded here.

Applicability hinges on specific modification and SB numbers

• The AD’s applicability excludes aircraft that have certain Airbus production modifications or service bulletins embodied in service. The exact identifiers are: Airbus modification 32616 incorporated during production, or Airbus SB A320-21-1141 embodied whilst in service; plus, for subtypes: A319 with Airbus modification 24486 incorporated during production or SB A320-21-1140 embodied whilst in service; A320 with Airbus modification 20084 or SB A320-21-1048 embodied; A321 with Airbus modification 22596 incorporated during production. Failure to correctly read maintenance and production records may lead an operator to mistakenly believe an aircraft is exempt when it is not, or vice versa. The AD’s exemptions are narrowly worded and depend on physical incorporation during production or specific SB embodiment while in service.

SB revision acceptance conditional on DGAC approval

• The AD allows compliance via "SB A320-21-1141 or later revision approved by the DGAC." That means operators cannot rely on arbitrary later SB revisions unless the DGAC has approved them. A later Airbus SB revision without DGAC approval would not satisfy the AD as printed. Operators must therefore check DGAC approval status before implementing an updated SB.

Compliance deadline extended but finite

• The amendment extends the compliance date to "Before 31 May 2007." That is an absolute deadline in the AD. There is no text in the AD that offers phased compliance, waivers, or interim operating limitations. Operators who delay must ensure the modification is completed by this date.

The AD addresses one identified leak source only

• The Background states two leak sources were identified: water drain valves and the aft cargo temperature sensor installation, and that the original Directive rendered mandatory the modification "to prevent the second air leak." That implies the AD specifically addresses the sensor leak, not necessarily the water drain valve leak. The AD text does not require modification of water drain valves; operators should not assume the AD deals with all cargo compartment leakage issues.

No penalties or enforcement mechanisms described

• The AD contains no enforcement or penalty clauses. Practitioners should not interpret the absence of such clauses as meaning non-compliance has no consequences; however, any enforcement actions, penalties or regulatory consequences are not described in this AD and would need to be sourced elsewhere.

Step 1 , Establish applicability

• Check each aircraft’s production records and maintenance logbooks to confirm whether any of the listed production modifications were incorporated during manufacture (Airbus mod numbers 24486 for A319, 20084 for A320, 22596 for A321, or 32616 referenced in the opening applicability clause), or whether the listed Airbus service bulletins were embodied whilst in service (A320-21-1140 for certain A319s, A320-21-1048 for certain A320s, or SB A320-21-1141 itself embodied). The AD’s Applicability table is the determinative text for exclusions; confirm by documentary evidence that the relevant mod or SB was incorporated.

Step 2 , If not excluded, obtain the SB and DGAC approval status

• If the aircraft is within the AD’s scope, obtain Airbus Service Bulletin A320-21-1141 and any later revisions. Verify whether a later revision exists and whether that revision has been approved by the DGAC. The AD permits embodiment of a later revision only if "approved by the DGAC." Do not rely on unapproved revisions for compliance.

Step 3 , Plan and schedule embodiment before the compliance date

• The AD deadline is "Before 31 May 2007." Schedule the modification in a maintenance window that allows the SB to be embodied per its technical instructions. Arrange parts, tools and suitably qualified personnel or an approved maintenance organisation to perform the work per the SB instructions.

Step 4 , Implement the technical modification per the SB instructions

• Carry out the modification "in accordance with the instructions given in SB A320-21-1141 or later revision approved by the DGAC." Since the AD delegates the technical steps to the SB, follow every procedural, inspection, calibration and test requirement in the SB to ensure correct embodiment.

Step 5 , Record completion and retain evidence

• Upon completion, record SB embodiment clearly in the aircraft maintenance log, identifying the SB number and revision and any DGAC approval of the revision, or record the applicable production modification number if that is the basis for exemption. Keep copies of work orders, parts invoices, release-to-service documentation and any DGAC approval letters for the SB revision if relied upon.

Step 6 , Verify continued airworthiness conformity

• Confirm that the modification and any tests are complete and that the aircraft meets the intended fire containment capability improvements specified in the SB. The AD’s background identified halon concentration loss due to air renewal; although the AD does not mandate a verification test, operators should ensure the aircraft’s continued airworthiness acceptability following the modification.