{"id":"F2009L01981","name":"AD/A330/88 Amdt 1 - Intermediate Pressure Turbine Overspeed Protection","slug":"ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":79190,"registerId":"commonwealth-F2009L01981-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Airbus Industrie A330 Series Aeroplanes","sectionType":"division","heading":"Airbus Industrie A330 Series Aeroplanes","content":"### Airbus Industrie A330 Series Aeroplanes\n\n| AD/A330/88 Amdt 1 | Intermediate Pressure TurbineOverspeed Protection | 6/2009 |\n| ----------------- | ------------------------------------------------- | ------ |\n\n| Applicability: | A330-243, -341, -342 and -343 models, all manufacturing serial numbers (MSN) except those on which Airbus modification 56722 has been embodied during production.                                                                                                                                                                                                                                                                                                     |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Perform a reprogramming of Data Entry Plug on both engines to activate Intermediate Pressure Turbine Overspeed protection function in accordance with the instructions of Airbus SB A330-73-3049 Revision 01 dated 13 November 2008 or later revision approved by the European Aviation Safety Agency (EASA).                                                                                                                                                         |\n|                | As the accomplishment of SB A330-73-3049 instructions has an operational consequence, the operator must contact Airbus to get the associated operational documentation.                                                                                                                                                                                                                                                                                               |\n|                | Modification of an aeroplane, prior to the effective date of this Amendment, in accordance with the instructions of SB A330-73-3049 original issue dated14 November 2007 is acceptable to comply with the requirements of this Amendment.                                                                                                                                                                                                                             |\n|                | Note: EASA AD 2009-0075 refers.                                                                                                                                                                                                                                                                                                                                                                                                                                       |\n| Compliance:    | No later than 31 July 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                           |\n|                | This Amendment becomes effective on 4 June 2009.                                                                                                                                                                                                                                                                                                                                                                                                                      |\n| Background:    | An operator of an A330 aircraft fitted with RR Trent 772 B engines experienced an engine #1 uncontained multiple turbine blade failure. Investigations have shown that High Pressure/Intermediate Pressure (HP/IP) oil vent tubes are prone to be affected by carbon deposit or to be damaged by their outer heat shields leading to a fire inside or outside the vent tube and resulting into IP Turbine (IPT) disc drive arm fracture and thus IPT disc over speed. |\n|                | If not corrected, IPT disc over speed could lead to an uncontained engine failure i.e. multiple turbine blade failure or HP/IP turbine disc burst, which would constitute an unsafe condition.                                                                                                                                                                                                                                                                        |\n\n|     | In order to protect IPT from over speed, the original issue of this Directive required the activation of the IPTOS protection function by DEP reprogramming, which consists in limiting the IPT speed (Engine Thrust) when overheat is detected in IPT, for all A330 aircraft fitted with RR Trent 700 engines and equipped with Multi Mode Receiver.              |\n| --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n|     | The original issue of this AD had a limited applicability due to Flight Warning Computer compatibility issue with aircraft not equipped with Multi Mode Receivers. Airbus has now developed a new Flight Warning Computer standard T2 whose embodiment is also possible on A330 aeroplane fitted with RR Trent 700 engines not equipped with Multi Mode Receivers. |\n|     | For these reasons, this Amendment retains the requirement of the original issue of this Directive and extends the applicability to all A330 aeroplanes fitted with RR Trent 700 engines. At the same time compliance is extended to 31 July 2009.                                                                                                                  |\n|     | The original issue of this Directive became effective on 28 August 2008.                                                                                                                                                                                                                                                                                           |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n24 April 2009","sortOrder":0},{"sectionNumber":"AD/A330/88 Amdt 1","sectionType":"part","heading":"AD/A330/88 Amdt 1","content":"## AD/A330/88 Amdt 1","sortOrder":1},{"sectionNumber":"Intermediate Pressure TurbineOverspeed P","sectionType":"part","heading":"Intermediate Pressure TurbineOverspeed Protection","content":"## Intermediate Pressure Turbine  \nOverspeed Protection","sortOrder":2},{"sectionNumber":"6/2009","sectionType":"part","heading":"6/2009","content":"## 6/2009","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This Amendment broadened the original Directive's scope. The original AD applied only to A330 aircraft fitted with Multi Mode Receivers because of Flight Warning Computer compatibility. The Amendment extends the requirement to all A330 aeroplanes fitted with Rolls‑Royce Trent 700 engines by noting Airbus has developed a Flight Warning Computer standard (T2) compatible with aircraft not fitted with Multi Mode Receivers, thereby increasing the population of affected aircraft. The Amendment also set a uniform compliance deadline (31 July 2009) and accepted prior accomplishment under the original service bulletin as compliant."},"complexity_factors":["Short one‑issue Airworthiness Directive focused on a single technical fix (DEP reprogramming)","Single main service bulletin referenced: Airbus SB A330‑73‑3049 Rev 01 (or later EASA‑approved revision)","One clear exception: aircraft with Airbus modification 56722 embodied in production","Cross‑reference to EASA AD 2009‑0075 and to the original SB issue (14 Nov 2007)","Operational documentation requirement (operators must contact Airbus) introduces a procedural dependency on the OEM","Simple, single compliance deadline and effective date (no rolling phases or complex conditional timelines)"],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- Requires operators of certain Airbus A330 aeroplanes to reprogram the Data Entry Plug (DEP) on both engines so that the Intermediate Pressure Turbine Overspeed protection function (IPTOS) is active. This must be done following the instructions in Airbus Service Bulletin A330-73-3049 Revision 01 (or a later EASA‑approved revision). (Requirement)\n- Applies to A330-243, -341, -342 and -343 aeroplanes, all serial numbers, except those which already had Airbus modification 56722 installed during production. (Applicability)\n- If an operator already carried out the original issue of the service bulletin (issued 14 Nov 2007) before this Amendment came into force, that work complies with the Amendment. (Requirement)\n- Operators must contact Airbus for any related operational documentation because the software change has operational consequences (for example, changes to engine limits or procedures). (Requirement)\n- Compliance deadline: reprogramming must be done by 31 July 2009. This Amendment became effective on 4 June 2009. (Compliance)\n\n**Who is affected**\n\n- Primary: Operators and registrants of applicable A330 models fitted with Rolls‑Royce Trent 700 engines (except aircraft with Airbus mod 56722 fitted in production). They must schedule and pay for DEP reprogramming and update operational documentation/procedures as directed by Airbus. (Applicability, Requirement)\n- Secondary: Maintenance organisations and approved engineers who will perform the reprogramming and record the modification; Airbus and Rolls‑Royce as equipment/service bulletin authors and suppliers of any required software; regulatory authorities responsible for oversight. (Requirement)\n\n**Why it matters (stated purpose and safety mechanics)**\n\n- The stated reason: investigations after an uncontained turbine failure showed HP/IP oil vent tubes can become blocked or damaged, causing fire and subsequent damage that can fracture the IP turbine disc drive arm and induce an IPT disc overspeed. IPT disc overspeed can lead to uncontained engine failures (multiple turbine blade failure or disc burst). (Background)\n- The DEP reprogramming activates an IPT overspeed protection function that limits IPT speed (and thus engine thrust) when IPT overheat is detected, reducing the risk of IPT overspeed and consequent uncontained failures. The Amendment extends that protection to a broader set of A330 aeroplanes. (Requirement, Background)\n\n**Operational and compliance implications — concise analysis**\n\n- Who pays: aircraft operators bear the direct costs — ground time, technician hours, potential software charges, and any crew/operations training or procedural updates required by Airbus. (Requirement)\n- Who decides/implements: operators in conjunction with their approved maintenance organisations will implement the DEP reprogramming; Airbus provides the technical instructions and the operational documentation changes. The regulator enforces the AD compliance. (Requirement)\n- Behavioural change: operators must schedule a DEP reprogramming event for each affected aeroplane and update operational procedures. If not already done, some aircraft may also require embodiment of the Flight Warning Computer standard T2 or equivalent compatibility measures before the protection can be activated. (Background)\n- Trade‑offs and opportunity costs: the measure imposes modest short‑term costs (downtime and maintenance labour) in order to reduce a low‑probability, high‑consequence engine failure risk. There may be minor impacts on engine performance if the protection constrains thrust during an IPT overheat condition; operators must weigh routine dispatch impacts against the safety benefit. (Requirement, Background)\n- Implementation risk and compliance burden: the instruction references a specific Airbus service bulletin and requires contact with Airbus for operational documentation. That centralises technical control with Airbus for operational changes, which creates dependence on the OEM for approved procedures and could lengthen administrative lead time before affected aircraft return to service. (Requirement)\n- Concentrated benefits and diffuse costs: the safety benefit (reduced risk of uncontained engine failure) is diffuse and affects passengers, crew and the public; costs (maintenance, scheduling) are concentrated on individual operators. The change also concentrates technical authority with Airbus for the operational adjustments that follow software activation. (Requirement, Background)\n\n**Other practical notes**\n\n- If modification in accordance with the original (14 Nov 2007) issue of SB A330‑73‑3049 was already done before this Amendment, no further action is needed to comply. (Requirement)\n- The Amendment explicitly references EASA AD 2009‑0075. (Requirement)\n\n(References in parentheses point to the labelled sections of the directive: Applicability, Requirement, Compliance, Background.)"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"This Amendment expands the scope of the original 2008 directive. The original AD only applied to A330 aircraft equipped with Multi Mode Receivers due to Flight Warning Computer compatibility limitations. This version extends coverage to all A330 aircraft fitted with Rolls-Royce Trent 700 engines, regardless of Multi Mode Receiver fitment, following Airbus development of a compatible Flight Warning Computer standard (T2). The compliance deadline was also extended from the original date to 31 July 2009."},"complexity_factors":["Single technical requirement with clear cross-reference to Airbus Service Bulletin","Limited conditional logic: only two applicability criteria (specific models AND exclusion for modification 56722)","One grandfathering provision (acceptance of earlier SB revision)","Minimal defined terms — relies on external technical documentation (EASA AD, Airbus SB)","Short, self-contained instrument with straightforward compliance date","Operational consequence noted but delegated to external Airbus documentation rather than detailed in the instrument itself"],"plain_english_summary":"This AD mandates a safety software reprogram on Airbus A330s with Rolls‑Royce Trent 700 engines to enable Intermediate Pressure Turbine Overspeed Protection (IPTOS), preventing dangerous IPT overspeed and potential uncontained turbine failure following an incident. It affects A330-243/-341/-342/-343 aircraft unless Airbus mod 56722 was fitted at manufacture.\n\nOperators must apply the Airbus Service Bulletin and update flight manual data by the directive’s compliance date (31 July 2009); earlier compliance under the Nov 2007 instructions remains valid."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection","history":"/api/acts/ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection/history","analysis":"/api/acts/ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection/analysis","conflicts":"/api/acts/ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection/conflicts","importantCases":"/api/acts/ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection/important-cases","documents":"/api/acts/ad-a330-88-amdt-1-intermediate-pressure-turbine-overspeed-protection/documents"}}