Jump to Content
Download Final Report
[PDF: 20.17MB]
 
 
Alternate: [DOCX: 20.56MB]
 

What happened

On 4 November 2010, while climbing through 7,000 ft after departing from Changi Airport, Singapore, the Airbus A380 registered VH-OQA, sustained an uncontained engine rotor failure (UERF) of the No. 2 engine, a Rolls-Royce Trent 900. Debris from the UERF impacted the aircraft, resulting in significant structural and systems damage.
The flight crew managed the situation and, after completing the required actions for the multitude of system failures, safely returned to and landed at Changi Airport.

What the ATSB found

The Australian Transport Safety Bureau (ATSB) found that a number of oil feed stub pipes within the High Pressure / Intermediate pressure (HP/IP) hub assembly were manufactured with thin wall sections that did not conform to the design specifications. These non-conforming pipes were fitted to Trent 900 engines, including the No. 2 engine on VH-OQA. The thin wall section significantly reduced the life of the oil feed stub pipe on the No. 2 engine so that a fatigue crack developed, ultimately releasing oil during the flight that resulted in an internal oil fire. That fire led to the separation of the intermediate pressure turbine disc from the drive shaft. The disc accelerated and burst with sufficient force that the engine structure could not contain it, releasing high-energy debris.

What has been done to fix it

Following the UERF, the ATSB, Rolls-Royce plc, regulatory authorities and operators of A380 aircraft with Trent 900 engines took a range of steps to ensure that HP/IP hub assemblies with non-conforming oil feed stub pipes were identified and either removed from service, or managed to ensure their safe continued operation. Rolls-Royce also released an engine control software update that included an IP turbine overspeed protection system (IPTOS) that is designed to shut the engine down before the turbine disc can overspeed, in the unlikely event that a similar failure occurs.

Rolls-Royce has also made a range of changes to their quality management system to improve the way in which they manage non-conforming parts, both during the manufacturing process and when it has been identified that parts had unknowingly been released into service with non-conformances.

Safety message

The ATSB identified a number of issues during the manufacture of Trent 900 HP/IP hub assemblies that resulted in their release into service with non-conforming oil feed stub pipes. Those issues highlighted the importance of providing clear procedures during the manufacturing process and of personnel complying with those procedures. Even though modern civil turbine engines are very reliable, and UERFs are very rare events, the resulting damage from such a failure can be significant and the potential effects catastrophic. This accident represents an opportunity for the regulatory authorities to incorporate any lessons learned into their certification advisory material to enhance the safety of future aircraft designs.

 

ATSB media release 27 June 2013

• Audio of media conference 27 June 2013 - [Download MP3 MP3 21MB

Download Final Report
[PDF: 20.17MB]
 
 
Alternate: [DOCX: 20.56MB]
 
 

Initial recommendation for misaligned stub pipe counter-boring that led to reduced wall thickness

Safety Issue

Misaligned stub pipe counter-boring is understood to be related to the manufacturing process. This condition could lead to an elevated risk of fatigue crack initiation and growth, oil leakage and potential catastrophic engine failure from a resulting oil fire.

As a result of the identified critical safety issue, the Australian Transport Safety Bureau issues the following safety recommendation:

Safety Recommendation AO-2010-089-SR-012

The Australian Transport Safety Bureau recommends that Rolls-Royce plc address the safety issue and take actions necessary to ensure the safety of flight operations in transport aircraft equipped with Rolls-Royce plc Trent 900 series engines.


 

Airframe certification standards in the case of an uncontained engine rotor failure - EASA

Safety issue

The evolution of the current advisory material relating to the minimisation of hazards resulting from uncontained engine rotor failures was based on service experience, including accident investigation findings. The damage to Airbus A380-842 VH-OQA exceeded the modelling used in the UERF safety analysis and, therefore, represents an opportunity to incorporate any lessons learned from this accident into the advisory material.

ATSB safety recommendation AO-2010-089-SR-039

The Australian Transport Safety Bureau recommends that the European Aviation Safety Agency, in cooperation with the US Federal Aviation Administration, review the damage sustained by Airbus A380-842, VH-OQA following the uncontained engine rotor failure overhead Batam Island, Indonesia, to incorporate any lessons learned from this accident into the advisory material.


 

Airframe certification standards in the case of an uncontained engine rotor failure - US FAA

Safety issue

The evolution of the current advisory material relating to the minimisation of hazards resulting from uncontained engine rotor failures was based on service experience, including accident investigation findings. The damage to Airbus A380-842 VH-OQA exceeded the modelling used in the UERF safety analysis and, therefore, represents an opportunity to incorporate any lessons learned from this accident into the advisory material.

ATSB safety recommendation AO-2010-089-SR-040

The Australian Transport Safety Bureau recommends that the US Federal Aviation Administration, in cooperation with the European Aviation Safety Agency, review the damage sustained by Airbus A380-842, VH-OQA following the uncontained engine rotor failure overhead Batam Island, Indonesia, to incorporate any lessons learned from this accident into the advisory material.

 

 
Download Interim Factual
[PDF: 319KB]
 
 
Alternate: [DOC: 256KB]
 

Interim Report Relased 18 May 2011

The Australian Transport Safety Bureau is investigating an occurrence involving a Qantas A380 aircraft that experienced an uncontained engine failure over Batam Island, Indonesia on 4 November 2010. The aircraft landed safely in Singapore having returned with the aircraft's No 2 engine shut down. There were no injuries.

The investigation team has inspected the damaged engine and components and determined the sequence of events that led to the failure of the engine disc.

The investigation is also examining the airframe and systems damage that resulted from the engine disc burst to understand its effect on those systems and the impact on flight safety. That includes their effect on the aircraft's handling and performance and on crew workload. A flight simulator program was used to conduct a number of tests in a certified A380 flight simulator. Analysis of the flight simulation test data is ongoing.

Download Interim Factual
[PDF: 319KB]
 
 
Alternate: [DOC: 256KB]
 
 
Download Preliminary Report
[PDF: 1.98MB]
 
 
Alternate: [DOC: 13.66MB]
 

Preliminary Report Released 3 December 2010

On 4 November 2010, at 0157 Universal Coordinated Time (UTC), an Airbus A380 aircraft, registered VH-OQA (OQA), being operated as Qantas flight 32, departed from runway 20 centre (20C) at Changi Airport, Singapore for Sydney, New South Wales. On board the aircraft were five flight crew, 24 cabin crew and 440 passengers (a total of 469 persons on board).

Following a normal takeoff, the crew retracted the landing gear and flaps. The crew reported that, while maintaining 250 kts in the climb and passing 7,000 ft above mean sea level, they heard two almost coincident 'loud bangs', followed shortly after by indications of a failure of the No 2 engine.

The crew advised Singapore Air Traffic Control of the situation and were provided with radar vectors to a holding pattern. The crew undertook a series of actions before returning the aircraft to land at Singapore. There were no reported injuries to the crew or passengers on the aircraft. There were reports of minor injuries to two persons on Batam Island, Indonesia.

A subsequent examination of the aircraft indicated that the No 2 engine had sustained an uncontained failure of the Intermediate Pressure (IP) turbine disc. Sections of the liberated disc penetrated the left wing and the left wing-to-fuselage fairing, resulting in structural and systems damage to the aircraft.

As a result of this occurrence, a number of safety actions were immediately undertaken by Qantas, Airbus, Rolls-Royce plc and the European Aviation Safety Agency. On 1 December 2010, the ATSB issued a safety recommendation to Rolls-Royce plc in respect of the Trent 900 series engine high pressure/intermediate pressure bearing structure oil feed stub pipes. In addition, the Civil Aviation Safety Authority issued a Regulation 38 maintenance direction that addressed the immediate safety of flight concerns in respect of Qantas A380 operations with the Trent 900 series engine. On 2 December 2010, Qantas advised that the requirements of Rolls-Royce plc Service Bulletin RB211-72-G595 would take place within the next 24 hours on engines in place on A380 aircraft currently in service, and before further flighton engines on aircraft not yet returned to service.

Download Preliminary Report
[PDF: 1.98MB]
 
 
Alternate: [DOC: 13.66MB]
 
 
 

To download an image click the download link then right-click the image and select save image as.

 

Safety issues

AO-2010-089-SI-01 - AO-2010-089-SI-02 - AO-2010-089-SI-03 - AO-2010-089-SI-04 - AO-2010-089-SI-05 - AO-2010-089-SI-06 - AO-2010-089-SI-07 - AO-2010-089-SI-08 - AO-2010-089-SI-09 - AO-2010-089-SI-10 - AO-2010-089-SI-11 - AO-2010-089-SI-12 - AO-2010-089-SI-13 -  

Initial recommendation for misaligned stub pipe counter-boring that led to reduced wall thickness

On 30 November 2010 the ATSB had, in close consultation with Rolls-Royce and the UK Air Accidents Investigation Branch, established that the occurrence was directly related to the fatigue cracking of an oil feed stub pipe within the No.2 engine’s HP/IP bearing support structure. The ATSB identified the following safety issue:

Safety issue
Misaligned stub pipe counter-boring is understood to be related to the manufacturing process. This condition could lead to an elevated risk of fatigue crack initiation and growth, oil leakage and potential catastrophic engine failure from a resulting oil fire.

  • During the manufacture of the HP/IP bearing support assembly fitted to the No. 2 engine (serial number 91045), movement of the hub during the machining processes resulted in a critically reduced wall thickness within the counter bore region of the oil feed stub pipe.
  • It was probable that a non-conformance in the location of the oil feed stub pipe interference bore was reported by the coordinate measuring machine during the manufacturing process, but that the non-conformance was either not detected or not declared by inspection personnel, resulting in the assembly being released into service with a reduced wall thickness in the oil feed stub pipe.
Issue Number:AO-2010-089-SI-01
Who it affects:Aircraft equipped with Rolls-Royce plc Trent 900 series engines
Status:Adequately addressed


 

Intermediate pressure turbine overspeed and burst following failure of drive arm due to internal engine fire

Following the separation of the IP turbine disc from the drive arm, the engine behaved in a manner that differed from the engine manufacturer’s modelling and experience with other engines in the Trent family, with the result that the IP turbine disc accelerated to a rotational speed in excess of its design capacity whereupon it burst in a hazardous manner.

Issue Number:AO-2010-089-SI-02
Who it affects:Ownres and operators of Trent 900 engines
Status:Adequately addressed


 

Release of non-conforming oil feed stub pipes into service

Numerous other engines within the Trent 900 fleet were also found to contain a critical reduction in the oil feed stub pipe wall thickness.

Issue Number:AO-2010-089-SI-03
Who it affects:Rolls-Royce plc, owners and operators of Trent 900 engines
Status:Adequately addressed


 

Consultation between manufacturing engineers and design engineers to ensure maintenance of design intent

The engine manufacturer did not require its manufacturing engineers to consult with the design engineers to ensure that design intent would be maintained when introducing manufacturing datums.

Issue Number:AO-2010-089-SI-04
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Use of manufacturing stage drawings for the first article inspection

The procedure for the first article inspection process contained ambiguities that resulted in an interpretation whereby the use of the manufacturing stage drawings was deemed to be acceptable.

Issue Number:AO-2010-089-SI-05
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Culture of acceptance of ‘minor’ non-conforming components during manufacture at the Rolls-Royce Hucknall facility

A culture existed within the engine manufacturer's Hucknall facility where it was considered acceptable to not declare what manufacturing personnel determined to be minor non-conformances in manufactured components.

Issue Number:AO-2010-089-SI-06
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Difference between drawing datum and coordinate measuring machine datum

The coordinate measuring machine was programmed to measure the location of the oil feed stub pipe interference bore with respect to the manufacturing datum, instead of the design definition datum as specified on both the design and manufacturing stage drawings.

Issue Number:AO-2010-089-SI-07
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Expert review of statistical analysis in support of retrospective concessions

The engine manufacturer did not have a requirement for an expert review of statistical analyses used in retrospective concession applications.

Issue Number:AO-2010-089-SI-08
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Chief Engineer and Business Quality Director review of retrospective concessions

The engine manufacturer's process for retrospective concessions did not specify when in the process the Chief Engineer and Business Quality Director approvals were to be obtained. Having them as the final approval in the process resulted in an increased probability that the fleet-wide risk assessment would not occur.

Issue Number:AO-2010-089-SI-09
Who it affects:Rolls-Royce plc
Status:Adequately addressed


 

Reporting of significant non-conformances to the quality review board

The engine manufacturer’s group quality procedures did not provide any guidance on how manufacturing personnel were to determine the significance of a non-conformance, from a quality assurance perspective.

Issue Number:AO-2010-089-SI-10
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Classification of the HP/IP bearing support assembly

The manufacturer’s classification, relating to the criticality of failure, of the HP/IP bearing support assembly was inappropriate for the effects of a fire within the buffer space and hence, the requirement for an appropriate level of process control was not communicated to the manufacturing staff.

Issue Number:AO-2010-089-SI-11
Who it affects:Engine manufacturer Rolls-Royce plc
Status:Adequately addressed


 

Landing distance calculation at aircraft weights below the A380 maximum landing weight

The calculation method in the aircraft manufacturer’s landing distance performance application was overly conservative and this could prevent the calculation of a valid landing distance at weights below the maximum landing weight with multiple system failures.

Issue Number:AO-2010-089-SI-12
Who it affects:Airbus SAS and operators of A380 aircraft
Status:Adequately addressed


 

Airframe certification standards in the case of an uncontained engine rotor failure - EASA

The evolution of the current advisory material relating to the minimisation of hazards resulting from uncontained engine rotor failures was based on service experience, including accident investigation findings. The damage to Airbus A380-842 VH-OQA exceeded the modelling used in the UERF safety analysis and, therefore, represents an opportunity to incorporate any lessons learned from this accident into the advisory material.

Issue Number:AO-2010-089-SI-13
Who it affects:Airframe certification authorities
Status:Partially addressed

 

General details

Date: 04 Nov 2010 Investigation status: Completed 
Time: 0201 UTC Investigation type: Occurrence Investigation 
Location   (show map):overhead Batam Island, Indonesia Occurrence type:Engine failure or malfunction 
State: International Occurrence class: Technical 
Release date: 27 Jun 2013 Occurrence category: Accident 
Report status: Final Highest injury level: None 
 

Aircraft details

Aircraft manufacturer: Airbus Industrie 
Aircraft model: A380 
Aircraft registration: VH-OQA 
Serial number: 14 
Type of operation: Air Transport High Capacity 
Damage to aircraft: Serious 
Departure point:Singapore
Destination:Sydney, NSW
 
 
Share this page Provide feedback on this investigation
Last update 25 March 2014