Qantas A380 uncontained #2 engine failure
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Mmurray said:
Dicks-airbus wrote:
Gosh! I think you must have stumbled on something here chaps - we ought to be told. Systematic disregard for standards and mission critical items at Rolls-Royce? Hold the press. 
I suggest you watch BBC2 'How to build a Jumbo Jet engine'. It may surprise you to learn that RR no longer hammer components out of red hot wrought iron with a club hammer - they have moved on. You would learn of machining Trent 1000 turbine blades - cast as a single crystal - to accuracies of about 3 microns.
I suspect every single employee at Rolls-Royce were as shocked and upset about that failure as Qantas and the people on the aeroplane. Unlike you Mr Mmurray, they are engineers - some of the world's finest and are probably as we write, working on the problem. That whatever happened was an aberration is certain, I'd bet that all of RR are determined to find out how, why and how to prevent it ever happening again is equally certain.
With this country, for the most part, having given up on making things, one of the few shining lights in creative engineering and successful marketing in trouble for whatever reason, is not a happy thought.
For what its worth, my support for Rolls-Royce and their beautifully engineered product is 100% - and I work for a competitor. 
Roger.
I'm no engineer but surely making an aircraft engine involves being able to machine parts better than this? Most DIYers could do a neater job than that.
Michael
Michael
If this is the way RR does QA we're in serious trouble.
I suggest you watch BBC2 'How to build a Jumbo Jet engine'. It may surprise you to learn that RR no longer hammer components out of red hot wrought iron with a club hammer - they have moved on. You would learn of machining Trent 1000 turbine blades - cast as a single crystal - to accuracies of about 3 microns.
I suspect every single employee at Rolls-Royce were as shocked and upset about that failure as Qantas and the people on the aeroplane. Unlike you Mr Mmurray, they are engineers - some of the world's finest and are probably as we write, working on the problem. That whatever happened was an aberration is certain, I'd bet that all of RR are determined to find out how, why and how to prevent it ever happening again is equally certain.
With this country, for the most part, having given up on making things, one of the few shining lights in creative engineering and successful marketing in trouble for whatever reason, is not a happy thought.
For what its worth, my support for Rolls-Royce and their beautifully engineered product is 100% - and I work for a competitor. Roger.
For "Flight Idle"
Jet Engines and Propulsion Systems For Engineers
Chapter 8-26
(pages 319-323 of pdf)
Jet Engines Engine
AXIAL BEARING THRUST CONTROL
Balancing the.axial thrust loads which develop in the flowpath and internal cavities of jet engines is critical to obtaining acceptable thrust bearing lives. Since the secondary systems air model includes all major cavities, a simple summation of pressure times projected area for all pertinent cavities will give the resultant load on all rotating hardware. Factoring in the compressor and turbine aerodynamic blade loads yields the axial forces on the engine thrust bearings.
HP Rotor Thrust Table 8.1 shows a schematic and tabulation of pressures, areas, and forces involved in obtaining me resultant loads on the high pressure rotor bearings of the CF6-80C engine at takeoff. Note that the resultant load (-4561 lb.) is small relative to the major cavity loads. This is typical of HP rotor bearing axial loads. Also, note that maximum cavity loads are substantially higher than either compressor or turbine total airfoil aerodynamic loads. Compare forces 104 and 114 with force 113 on Table 8.1. The accuracy of predicting these cavity pressures is a critical factor in predicting bearing loads.
Once the bearing load is predicted and determined to be too high for acceptable bearing life it can usually be adjusted to required levels by moving a critical seal to a larger or smaller diameter thus changing its projected area.. For instance, in Table 8.1, changing the diameter of the seal which affects forces 105 and 106 would be used to balance the load on the HP thrust bearing. In drastic cases if more adjustment is necessary, several seals or even turbine airfoil changes may be required to obtain desired bearing loads. Figure 8.24 shows a comparison of four different engines axial HP load and how they change with engine speed.
LP Rotor Thrust Prediction of the low pressure rotor thrust bearing load is generally much easier mainly due to the lower pressure levels involved. The principles remain the same. Figure 8.25 shows the low pressure rotor thrust for the same CF6-80C engine. Note that the predicted load is very close to the measured data presented in the figure.
Table 8.1 Variables Affecting Loads On High Pressure Rotor Bearings
NO Rt RO CHAM AREA PRESS FORCE
101 3.19 3.845 30 14.48 19.69 -285
102 3.845 4.840 33 27.16 33.07 -898
103 4.840 6.944 5 77.89 24.71 -1925
104 1 1 — — — +5783
105 7.640 11.825 7 253.92 364.65 +9332
106 6.375 7.650 36 55.70 102.82 +5727
107 4.650 6.375 59 59.75 22.75 +1359
108 4.000 4.650 41 17.66 26.65 +471
109 4.000 4.075 58 1,90 20.93 +40
110 4.325 5.050 62 21.35 21.32 -451
111 5.050 6.200 39 40.64 105.14 -4273
112 6.200 7.470 40 54.34 316.95 -1130£
113 7.470 4.040 10 448.39 253.99 -118879
114 1 1 — — — -31856
115 12.89 1.825 11 85.04 186.08 -17448
116 12.89 14.00 12 93.77 128.76 -8282
117 6.830 13.660 51 64.23 76.22 +41339
118 4.425 3.543 54 429.66 83.70 +7118
119 2.925 6.830 50 85.04 25.09 + 869
Jet Engines and Propulsion Systems For Engineers
Chapter 8-26
(pages 319-323 of pdf)
Jet Engines Engine
AXIAL BEARING THRUST CONTROL
Balancing the.axial thrust loads which develop in the flowpath and internal cavities of jet engines is critical to obtaining acceptable thrust bearing lives. Since the secondary systems air model includes all major cavities, a simple summation of pressure times projected area for all pertinent cavities will give the resultant load on all rotating hardware. Factoring in the compressor and turbine aerodynamic blade loads yields the axial forces on the engine thrust bearings.
HP Rotor Thrust Table 8.1 shows a schematic and tabulation of pressures, areas, and forces involved in obtaining me resultant loads on the high pressure rotor bearings of the CF6-80C engine at takeoff. Note that the resultant load (-4561 lb.) is small relative to the major cavity loads. This is typical of HP rotor bearing axial loads. Also, note that maximum cavity loads are substantially higher than either compressor or turbine total airfoil aerodynamic loads. Compare forces 104 and 114 with force 113 on Table 8.1. The accuracy of predicting these cavity pressures is a critical factor in predicting bearing loads.
Once the bearing load is predicted and determined to be too high for acceptable bearing life it can usually be adjusted to required levels by moving a critical seal to a larger or smaller diameter thus changing its projected area.. For instance, in Table 8.1, changing the diameter of the seal which affects forces 105 and 106 would be used to balance the load on the HP thrust bearing. In drastic cases if more adjustment is necessary, several seals or even turbine airfoil changes may be required to obtain desired bearing loads. Figure 8.24 shows a comparison of four different engines axial HP load and how they change with engine speed.
LP Rotor Thrust Prediction of the low pressure rotor thrust bearing load is generally much easier mainly due to the lower pressure levels involved. The principles remain the same. Figure 8.25 shows the low pressure rotor thrust for the same CF6-80C engine. Note that the predicted load is very close to the measured data presented in the figure.
Table 8.1 Variables Affecting Loads On High Pressure Rotor Bearings
NO Rt RO CHAM AREA PRESS FORCE
101 3.19 3.845 30 14.48 19.69 -285
102 3.845 4.840 33 27.16 33.07 -898
103 4.840 6.944 5 77.89 24.71 -1925
104 1 1 — — — +5783
105 7.640 11.825 7 253.92 364.65 +9332
106 6.375 7.650 36 55.70 102.82 +5727
107 4.650 6.375 59 59.75 22.75 +1359
108 4.000 4.650 41 17.66 26.65 +471
109 4.000 4.075 58 1,90 20.93 +40
110 4.325 5.050 62 21.35 21.32 -451
111 5.050 6.200 39 40.64 105.14 -4273
112 6.200 7.470 40 54.34 316.95 -1130£
113 7.470 4.040 10 448.39 253.99 -118879
114 1 1 — — — -31856
115 12.89 1.825 11 85.04 186.08 -17448
116 12.89 14.00 12 93.77 128.76 -8282
117 6.830 13.660 51 64.23 76.22 +41339
118 4.425 3.543 54 429.66 83.70 +7118
119 2.925 6.830 50 85.04 25.09 + 869
At the risk of continuing a potentially unpopular discussion on thrust loads, I confess my earlier simplistic analysis of fan loads appears to have been somewhat erroneous.
Apologies for questioning your input on this Barit1.
I would still like to better understand how the actual thrust forces do get transmitted to the pylon, as this now puzzles me somewhat if the anecdotal "80% of the thrust comes from the fan" is true.
I can understand the need to cancel thrust loads as much as possible on the HP spool which doesn't need to produce thrust as such - the link above does show how this is minimised by design.
It does seem somewhat different on the LP spool however. The link above on a CF6 (around 50,000lbs total thrust) still shows thrust loads of 15,000Ibs on the LP shaft at 3000rpm. This is still a large load, and hence far from being totally balanced by pressure loads on the disc faces, but admittedly this is far from the 30-40,000lbs I would have previously simplistically expected from such a high by-pass turbofan, assuming the fan produces most of the thrust.
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Facts
Landroger seems to have expressed the correct sentiment, in my view.
I doubt RR gave any thought to its share price when the failure happened - it just wanted to get to the bottom of things. It did so very quickly as best I can tell. RR could not, however, pre-empt the ATSB and I suspect the ATSB has had to wrestle with many of the same - intriguing - technical issues discussed in this forum.
As for 80% of the thrust coming from the 'big fan', I don't see what there is to question.
There are some technical aspects of the Trent 900 that might have given one pause for thought - they have been raised on this thread. What the ATSB has reported comes as a relief in some respects, although that is not to excuse the events that unfolded.
I doubt RR gave any thought to its share price when the failure happened - it just wanted to get to the bottom of things. It did so very quickly as best I can tell. RR could not, however, pre-empt the ATSB and I suspect the ATSB has had to wrestle with many of the same - intriguing - technical issues discussed in this forum.
As for 80% of the thrust coming from the 'big fan', I don't see what there is to question.
There are some technical aspects of the Trent 900 that might have given one pause for thought - they have been raised on this thread. What the ATSB has reported comes as a relief in some respects, although that is not to excuse the events that unfolded.
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We thought we had fixed it!
My background is in analysing 'in service' failures. Not aerospace but computers - in the days when they cost serious bucks!
We NEVER had a fault that manufacturing had not seen before and either believed ( or hoped!) was a one-off. When you stand up and put a production line on hold in the ramp-up phase of new product the political pressure is enormous. I have spent months finding the root-cause of problems only to have some guy, pass me a report in a bar, showing that the very same failure was seen in manufacturing months before. In parallel with his/her heroic action the boss' boss was trying to get me fired.
I doubt that any of this is truly news to RR as a whole.
We NEVER had a fault that manufacturing had not seen before and either believed ( or hoped!) was a one-off. When you stand up and put a production line on hold in the ramp-up phase of new product the political pressure is enormous. I have spent months finding the root-cause of problems only to have some guy, pass me a report in a bar, showing that the very same failure was seen in manufacturing months before. In parallel with his/her heroic action the boss' boss was trying to get me fired.
I doubt that any of this is truly news to RR as a whole.
As for 80% of the thrust coming from the 'big fan', I don't see what there is to question.
50,000lbs total thrust
High bypass fan (hence estimate "80% from fan")
= 40,000lbs thrust from fan
BUT
only 15,000lbs axial thrust loading on LP bearing according to the link
The question is...
How does the "other 25,000lbs" of thrust from the fan get transmitted to the pylon to push the aircraft along?
+1 on agreeing with Rogers post, to stay at least partly on topic.....
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How does the "other 25,000lbs" of thrust from the fan get transmitted to the pylon to push the aircraft along?
A similar process presumably happens for the other turbines and cavities. So directly or indirectly, that 25,000 pounds force acts on the IPT and HPT thrust bearings and on the front ends of the various cavities. As there is a small net force on the IPT and HPT thrust bearings, the vast majority of that force must presumably act on the front static parts of the cavities.
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Originally Posted by jfz90
The question is...
How does the "other 25,000lbs" of thrust from the fan get transmitted to the pylon to push the aircraft along?
How does the "other 25,000lbs" of thrust from the fan get transmitted to the pylon to push the aircraft along?
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The whole thing about exactly where the thrust comes from and how it gets transferred is not at all obvious.
If the engine is treated as a black box, basic formulae of "how much air (mass) enters at what speed and pressure" and "how much air (mass) exits at what speed and pressure" will give you the thrust.
But where exactly that thrust is generated, at what location in the engine, and how it's transferred to the rest of the aircraft structure, is a totally different story.
On Concorde, at supersonic cruise, about two-thirds (!) of the thrust came from.... the intakes.
Concorde engine intake "Thrust".
But even in a Trent, it's not the fan that's "dragging" the aircraft along by the shaft.
Unless you take all the pressure distributions into account, the discussion makes little sense.
CJ
If the engine is treated as a black box, basic formulae of "how much air (mass) enters at what speed and pressure" and "how much air (mass) exits at what speed and pressure" will give you the thrust.
But where exactly that thrust is generated, at what location in the engine, and how it's transferred to the rest of the aircraft structure, is a totally different story.
On Concorde, at supersonic cruise, about two-thirds (!) of the thrust came from.... the intakes.
Concorde engine intake "Thrust".
But even in a Trent, it's not the fan that's "dragging" the aircraft along by the shaft.
Unless you take all the pressure distributions into account, the discussion makes little sense.
CJ
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ATSB Preliminary (Factual) Report
The ATSB preliminary report is out. The investigation page can be found at Investigation: AO-2010-089 - Inflight engine failure - Qantas, Airbus A380, VH-OQA, overhead Batam Island, Indonesia, 4 November 2010 while a direct link to the preliminary report PDF is at http://www.atsb.gov.au/media/2888854...ort.pdf#page=0
I hope those who earlier in this thread were advocating a "get down quick" approach have a good read.
I hope those who earlier in this thread were advocating a "get down quick" approach have a good read.
Last edited by pct085; 2nd Dec 2010 at 23:10.
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"I hope those who earlier in this thread were advocating a "get down quick" approach have a good read."
Flightsimmers. Nobody took them seriously, did they?
Flightsimmers. Nobody took them seriously, did they?
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JFZ90
Thirty Tonnes of the available 36 is converted from Thrust into Radial (Torque) Energy. (By the LPT).
This Power is translated forward to the Fan, where it reconverts to thrust.
The Fan doesn't necessarily need to be in front. It could as well be mounted behind the LP turbine, directly affixed to it, and turning Thrust into Fan Power.
If that was the configuration, is it easier to envision the Power pushing against the Pylon through the Engine's gas Pressure?
edit: The Stub Pipe has wear on its lip as well as the seeming eccentric bore. The end of the pipe looks a whole lot like half a line coupling, misjoined. Is this a component of an Oil Line?, Or simply a suck tube for oil scavenge? The reason I ask is that were it a line that loosed, the oil supply may have drowned the case, causing an immediate fire, whereas if a plugged return, the failure may have been less instant. If necessary, take a pill before reading this, as it involves an active imagination.
bear
Thirty Tonnes of the available 36 is converted from Thrust into Radial (Torque) Energy. (By the LPT).
This Power is translated forward to the Fan, where it reconverts to thrust.
The Fan doesn't necessarily need to be in front. It could as well be mounted behind the LP turbine, directly affixed to it, and turning Thrust into Fan Power.
If that was the configuration, is it easier to envision the Power pushing against the Pylon through the Engine's gas Pressure?
edit: The Stub Pipe has wear on its lip as well as the seeming eccentric bore. The end of the pipe looks a whole lot like half a line coupling, misjoined. Is this a component of an Oil Line?, Or simply a suck tube for oil scavenge? The reason I ask is that were it a line that loosed, the oil supply may have drowned the case, causing an immediate fire, whereas if a plugged return, the failure may have been less instant. If necessary, take a pill before reading this, as it involves an active imagination.
bear
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2.4 mm 3D Borescope - -Hmmm
I had decided not to log in and put a comment in - - but !
I was a trained specialist on the IPLEX 3D measurement system 5 years back - - and have kept up to date with new technology since then .
If I am still up to date , the IPLEX system only has 3D presentation by way of special Video Spectacles and I think it still remains a 2D "Screen" presentation system to this day .
I am almost sure that a 2.4 mm scope if used would only be a "Fiberscope" fitted with a TV Camera and then again it would only be 2D .
These Flexible Digital Image probes and Fiberscope's are extremely unhappy in Oily
locations - - - the Image is only good when the environment is very clean !
Perhaps its another manufacturers system - - but 3D display at even 4 mm would be fantastic and almost certainly an optical specialist "Only " tool.
I was a trained specialist on the IPLEX 3D measurement system 5 years back - - and have kept up to date with new technology since then .
If I am still up to date , the IPLEX system only has 3D presentation by way of special Video Spectacles and I think it still remains a 2D "Screen" presentation system to this day .
I am almost sure that a 2.4 mm scope if used would only be a "Fiberscope" fitted with a TV Camera and then again it would only be 2D .
These Flexible Digital Image probes and Fiberscope's are extremely unhappy in Oily
locations - - - the Image is only good when the environment is very clean !
Perhaps its another manufacturers system - - but 3D display at even 4 mm would be fantastic and almost certainly an optical specialist "Only " tool.
In post 1012 a passenger described flames he saw in the wing. I wonder if that explains the "dark residue" the ATSB found on the interior of the fuel tank. I guess we'll know for sure once they finish analyzing it.
Looking at the pic of the tube, it must be in the region of 20mm diameter, if the 5mm is a scale reference.
Are there any other views of it?
Are there any other views of it?
High resolution version of counter-bore problem as posted by ATSB
depending on your browser and system, you may need to click again in the resulting image to zoom to full pixel/pixel resolution.
I'm posting this as a link to the ATSB hosted copy rather than hosting it on my site for in-line display as I think the resulting image size would be too big. If the ATSB link turns out to be transient, I'll edit the post to point to my backup copy.
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The Australian Transportation Safety Board ATSB have released their preliminary report reporting, that the flight crew consisted of 5 pilots: the captain (PIC), the first officer (FO), a second officer (SO), a second captain undergoing training as a check captain (CC) and a supervising check captain (SCC) overseeing the training of the second captain.
The flight was planned to fly to the east of active Merapi volcano. The PIC was pilot flying in the left hand seat, the FO was in the right hand seat, the CC in the center observer's seat, the SCC in the left hand observer's and the SO in the right hand observer's seat.
The crew reported later, that following departure from Singapore's runway 20C and after retracting gear and retracting the flaps they were climbing at 250 KIAS through 7000 feet when they heard two almost coincident loud bangs. The PIC selected altitude hold and heading hold immediately on the master control panel and the first officer started his stopwatch. The crew observed a slight yaw, the airplane levelled off. The crew expected the autothrottle to reduce engine thrust however it became evident autothrottle was no longer active and the engine thrust was reduced manually in order to maintain 250 KIAS. Both flight directors remained available to the crew. An engine #2 overheat warning was displayed on the ECAM soon followed by multiple messages.
The crew actioned the engine overheat checklist which required the engine to be throttled back to idle and monitor the situation for 30 seconds. During those 30 seconds a PAN call was transmitted. The FO noticed a fire indication for engine #2 for about 1-2 seconds before the display returned to overheat. The crew elected to shut the engine down, following the shut down the ECAM indicated the engine had failed.
The crew assessed that there was serious damage and elected to discharge a fire bottle into engine #2, but contrary to their expectations they did not get indication that the bottle had discharged. They discharged again but again received no confirmation that the bottle had discharged. They then decided to discharge the second bottle into engine #2 but again received no confirmation. The crew elected to continue the checklist and noticed that #2 was shown failed, engines #1 and #4 in degraded mode, #3 was operating in alternate mode. The ECAM continued to show numerous messages.
The flight crew recalled they received the following failures:
- engine #2 failed
- engine #1 and #4 in degraded mode
- green hydraulics low pressure and low quantity
- yellow hydraulics engine #4 pump error
- failure of AC electrical busses 1 and 2
- flight controls in alternate mode
- wing slats inoperative
- ailerons partial control only
- reduced spoiler control
- landing gear control and indicator warnings
- multiple brake system messages
- engine anti-ice and air data sensor messages
- multiple fuel system messages including fuel jettison fault
- center of gravity messages
- autothrust and autoland inoperative
- #1 engine generator disconnected
- left wing pneumatic bleed leaks
- avionic system overheat
The crew discussed whether to immediately return to Singapore, climbing or holding and decided the best option was to maintain altitude while processing the ECAM messages.
The crew frequently assessed the fuel on board which was sufficient to complete the checklist procedures. The aircraft remained controllable. They advised ATC they would need about 30 minutes to process the ECAM messages and requested to hold for that period. Singapore cleared the flight for a holding east of Singapore, the flight crew advised however they needed to remain within 30nm of Singapore Airport in case they needed to land immediately. ATC advised that residents at Batam had found debris on the ground, then vectored the aircraft to a 20nm holding pattern east of Singapore Airport.
While the crew processed the ECAM messages the SO was dispatched to the cabin to assess the damage to the #2 engine. While he walked through the cabin a passenger, also Qantas pilot, pointed out that pictures from the vertical fin mounted camera suggested a fluid leak from the left hand wing. The SO walked down to the lower deck of the passenger cabin and observed damage to the wing and a fluid leak that appeared to be about 0.5 meters wide. He could not see the turbine area of the engine from any position in the cabin. The SO returned to the cockpit and reported his observations.
The crew stopped re-arranging the fuel system doubting the integrity of the system. They could not dump fuel due to the fuel jettison error message. The operator sent ACARS messages that they had received multiple ACARS messages indicating various system failures from the automatic reporting system, the crew was busy with the ECAM messages and found time to just acknowledge the ACARS transmissions.
The PIC and SSC made a number of announcements to the passengers advising that they had technical problems, they were working to address these issues and it would take some time to do so. Subsequently the SO and SSC went to the cabin frequently to check the left hand side of the aircraft and to provide feedback to cabin crew and passengers.
It took about 50 minutes to complete the checklist procedures associated with the ECAM messages. During that time the autopilot was engaged. The crew then assessed which systems were operative, degraded and failed and discussed the impact on landing performance. They also believed that engine #1 may have been damaged and discussed a number of concerns regarding fuel imbalances that had been indicated by the ECAM.
The crew determined their landing weight would be 440 tons, about 50 tons above maximum landing weight, and computed the required landing distance with the systems available. The computation showed, that a landing on runway 20C was feasable with 100 meters of runway remaining. The crew elected to proceed on basis of this computation and advised ATC accordingly. The crew advised further they needed emergency services at the upwind end of the runway, fluid was leaking from the left wing that was likely to include hydraulic fluid and fuel.
Prior to leaving the holding pattern the crew discussed controllability of the aircraft and performed a number of manual checks at the holding speed. The crew requested a 20nm final to runway 20C to commence from 4000 feet, ATC fulfilled that request.
While the crew began the approach and lowered flaps they conducted further controllability tests at the approach speed and decided the airplane was controllable. The landing gear was lowered using the emergency extension procedure, a further controllability check was conducted.
The approach speed was computed at 166 KIAS. The crew was aware that reverse thrust was available only from the #3 engine, no leading edge slats were available, there was limited aileron and spoiler control, anti-skid was restricted to the body gear only, there was limited nose wheel steering and the nose would likely pitch up on landing. An ECAM message indicated they could not apply maximum braking until the nose wheel was on the runway. The flaps were extended to position 3.
ATC vectored the aircraft for a 20nm final progressively descending the aircraft to 4000 feet, the PIC was aware that speed control was necessary to avoid an aerodynamic stall and a runway overrun. Consequently the PIC set engine #1 and #4 to symmetric thrust and controlled the speed of the aircraft with the #3 engine. The autopilot disconnected a number of times during the initial approach, the airspeed dropped to 165 KIAS. The PIC reconnected the autopilot a number of times but when the autopilot disengaged again at 1000 feet he decided to fly manually for the remainder of the flight. Due to the limited runway margin available the CC reminded the PIC that the landing had to be done without flare and there would be a slightly higher nose up attitude during touch down.
The flight crew briefed the cabin crew for a possible runway overrun and evacuation.
The airplane touched down on Singapore's runway 20C 109 minutes after departure and within 6 seconds the nose wheel touched down and maximum braking was applied, reverse thrust was selected on the #3 engine. The crew felt that initially the deceleration was slow but with maximum braking and reverse thrust the airplane began to decelerate. The PIC felt confident the airplane would stop on the runway after the airplane had decelerated to 60 knots, and moved engine #3 gradually out of maximum reverse thrust. Manual braking was continued and the airplane stopped about 150 meters before the runway end.
The crew then shut down the remaining 3 engines, the aircraft electrical systems went into a configuration similiar to an emergency electrical power mode which blanked most of the cockpit displays. Just prior to the displays going blank the crew observed the body gear temperature rising to 900 degrees C and above. After some confusion which of the VHF radios remained available the FO contacted fire services who requested engine #1 to be shut down. The crew replied engine #1 was already shut down but was advised that the engine continued to run. The crew recycled the engine #1 master switch, but the engine continued to run. The crew used the emergency shut off switch and fire extinguisher bottles, but the engine continued to run. The fire commander advised there was fuel leaking from the left hand wing, the FO advised of the hot brakes and requested fire retardant foam to be applied over that fuel. The fire commander complied with that request.
After assessing the checklists the crew decided the safest course of action would be to disembark the passengers through the right hand doors via stairs. A single door was elected so that the passengers could be counted and the other doors remained available should a rapid evacuation via slides become necessary.
Crew contacted the operator via mobile phone to check how to shut engine #1 down.
The first passenger disembarked through the #2 main deck forward door 55 minutes after landing, the last passenger disembarked about 1 hour later.
The crew was advised by the fire commander that 4 tyres of the left body gear had deflated. Further attempts to shut engine #1 down were without success, operator advice to activate a number of circuit breakers in the electronic bay also remained unsuccessful. Attempts were made to re-arrange the fuel supply in order to starve engine #1, however due to lack of electrical power that was not possible.
Finally the decision was made to drown the engine with fire fighting foam. The engine finally stopped about 127 minutes after landing.
No injuries occurred on board of the aircraft. Two persons received minor injuries on the ground at the Island of Batam.
The PIC had a total experience of 15104 hours thereof 570 on the A380, the FO had 11279 hours thereof 1271 hours on the A380, the SO had 8153 hours thereof 1005 on type, the CC had 20144 hours thereof 806 on the A380 and the SCC had 17692 hours thereof 1345 hour on type.
The flight was planned to fly to the east of active Merapi volcano. The PIC was pilot flying in the left hand seat, the FO was in the right hand seat, the CC in the center observer's seat, the SCC in the left hand observer's and the SO in the right hand observer's seat.
The crew reported later, that following departure from Singapore's runway 20C and after retracting gear and retracting the flaps they were climbing at 250 KIAS through 7000 feet when they heard two almost coincident loud bangs. The PIC selected altitude hold and heading hold immediately on the master control panel and the first officer started his stopwatch. The crew observed a slight yaw, the airplane levelled off. The crew expected the autothrottle to reduce engine thrust however it became evident autothrottle was no longer active and the engine thrust was reduced manually in order to maintain 250 KIAS. Both flight directors remained available to the crew. An engine #2 overheat warning was displayed on the ECAM soon followed by multiple messages.
The crew actioned the engine overheat checklist which required the engine to be throttled back to idle and monitor the situation for 30 seconds. During those 30 seconds a PAN call was transmitted. The FO noticed a fire indication for engine #2 for about 1-2 seconds before the display returned to overheat. The crew elected to shut the engine down, following the shut down the ECAM indicated the engine had failed.
The crew assessed that there was serious damage and elected to discharge a fire bottle into engine #2, but contrary to their expectations they did not get indication that the bottle had discharged. They discharged again but again received no confirmation that the bottle had discharged. They then decided to discharge the second bottle into engine #2 but again received no confirmation. The crew elected to continue the checklist and noticed that #2 was shown failed, engines #1 and #4 in degraded mode, #3 was operating in alternate mode. The ECAM continued to show numerous messages.
The flight crew recalled they received the following failures:
- engine #2 failed
- engine #1 and #4 in degraded mode
- green hydraulics low pressure and low quantity
- yellow hydraulics engine #4 pump error
- failure of AC electrical busses 1 and 2
- flight controls in alternate mode
- wing slats inoperative
- ailerons partial control only
- reduced spoiler control
- landing gear control and indicator warnings
- multiple brake system messages
- engine anti-ice and air data sensor messages
- multiple fuel system messages including fuel jettison fault
- center of gravity messages
- autothrust and autoland inoperative
- #1 engine generator disconnected
- left wing pneumatic bleed leaks
- avionic system overheat
The crew discussed whether to immediately return to Singapore, climbing or holding and decided the best option was to maintain altitude while processing the ECAM messages.
The crew frequently assessed the fuel on board which was sufficient to complete the checklist procedures. The aircraft remained controllable. They advised ATC they would need about 30 minutes to process the ECAM messages and requested to hold for that period. Singapore cleared the flight for a holding east of Singapore, the flight crew advised however they needed to remain within 30nm of Singapore Airport in case they needed to land immediately. ATC advised that residents at Batam had found debris on the ground, then vectored the aircraft to a 20nm holding pattern east of Singapore Airport.
While the crew processed the ECAM messages the SO was dispatched to the cabin to assess the damage to the #2 engine. While he walked through the cabin a passenger, also Qantas pilot, pointed out that pictures from the vertical fin mounted camera suggested a fluid leak from the left hand wing. The SO walked down to the lower deck of the passenger cabin and observed damage to the wing and a fluid leak that appeared to be about 0.5 meters wide. He could not see the turbine area of the engine from any position in the cabin. The SO returned to the cockpit and reported his observations.
The crew stopped re-arranging the fuel system doubting the integrity of the system. They could not dump fuel due to the fuel jettison error message. The operator sent ACARS messages that they had received multiple ACARS messages indicating various system failures from the automatic reporting system, the crew was busy with the ECAM messages and found time to just acknowledge the ACARS transmissions.
The PIC and SSC made a number of announcements to the passengers advising that they had technical problems, they were working to address these issues and it would take some time to do so. Subsequently the SO and SSC went to the cabin frequently to check the left hand side of the aircraft and to provide feedback to cabin crew and passengers.
It took about 50 minutes to complete the checklist procedures associated with the ECAM messages. During that time the autopilot was engaged. The crew then assessed which systems were operative, degraded and failed and discussed the impact on landing performance. They also believed that engine #1 may have been damaged and discussed a number of concerns regarding fuel imbalances that had been indicated by the ECAM.
The crew determined their landing weight would be 440 tons, about 50 tons above maximum landing weight, and computed the required landing distance with the systems available. The computation showed, that a landing on runway 20C was feasable with 100 meters of runway remaining. The crew elected to proceed on basis of this computation and advised ATC accordingly. The crew advised further they needed emergency services at the upwind end of the runway, fluid was leaking from the left wing that was likely to include hydraulic fluid and fuel.
Prior to leaving the holding pattern the crew discussed controllability of the aircraft and performed a number of manual checks at the holding speed. The crew requested a 20nm final to runway 20C to commence from 4000 feet, ATC fulfilled that request.
While the crew began the approach and lowered flaps they conducted further controllability tests at the approach speed and decided the airplane was controllable. The landing gear was lowered using the emergency extension procedure, a further controllability check was conducted.
The approach speed was computed at 166 KIAS. The crew was aware that reverse thrust was available only from the #3 engine, no leading edge slats were available, there was limited aileron and spoiler control, anti-skid was restricted to the body gear only, there was limited nose wheel steering and the nose would likely pitch up on landing. An ECAM message indicated they could not apply maximum braking until the nose wheel was on the runway. The flaps were extended to position 3.
ATC vectored the aircraft for a 20nm final progressively descending the aircraft to 4000 feet, the PIC was aware that speed control was necessary to avoid an aerodynamic stall and a runway overrun. Consequently the PIC set engine #1 and #4 to symmetric thrust and controlled the speed of the aircraft with the #3 engine. The autopilot disconnected a number of times during the initial approach, the airspeed dropped to 165 KIAS. The PIC reconnected the autopilot a number of times but when the autopilot disengaged again at 1000 feet he decided to fly manually for the remainder of the flight. Due to the limited runway margin available the CC reminded the PIC that the landing had to be done without flare and there would be a slightly higher nose up attitude during touch down.
The flight crew briefed the cabin crew for a possible runway overrun and evacuation.
The airplane touched down on Singapore's runway 20C 109 minutes after departure and within 6 seconds the nose wheel touched down and maximum braking was applied, reverse thrust was selected on the #3 engine. The crew felt that initially the deceleration was slow but with maximum braking and reverse thrust the airplane began to decelerate. The PIC felt confident the airplane would stop on the runway after the airplane had decelerated to 60 knots, and moved engine #3 gradually out of maximum reverse thrust. Manual braking was continued and the airplane stopped about 150 meters before the runway end.
The crew then shut down the remaining 3 engines, the aircraft electrical systems went into a configuration similiar to an emergency electrical power mode which blanked most of the cockpit displays. Just prior to the displays going blank the crew observed the body gear temperature rising to 900 degrees C and above. After some confusion which of the VHF radios remained available the FO contacted fire services who requested engine #1 to be shut down. The crew replied engine #1 was already shut down but was advised that the engine continued to run. The crew recycled the engine #1 master switch, but the engine continued to run. The crew used the emergency shut off switch and fire extinguisher bottles, but the engine continued to run. The fire commander advised there was fuel leaking from the left hand wing, the FO advised of the hot brakes and requested fire retardant foam to be applied over that fuel. The fire commander complied with that request.
After assessing the checklists the crew decided the safest course of action would be to disembark the passengers through the right hand doors via stairs. A single door was elected so that the passengers could be counted and the other doors remained available should a rapid evacuation via slides become necessary.
Crew contacted the operator via mobile phone to check how to shut engine #1 down.
The first passenger disembarked through the #2 main deck forward door 55 minutes after landing, the last passenger disembarked about 1 hour later.
The crew was advised by the fire commander that 4 tyres of the left body gear had deflated. Further attempts to shut engine #1 down were without success, operator advice to activate a number of circuit breakers in the electronic bay also remained unsuccessful. Attempts were made to re-arrange the fuel supply in order to starve engine #1, however due to lack of electrical power that was not possible.
Finally the decision was made to drown the engine with fire fighting foam. The engine finally stopped about 127 minutes after landing.
No injuries occurred on board of the aircraft. Two persons received minor injuries on the ground at the Island of Batam.
The PIC had a total experience of 15104 hours thereof 570 on the A380, the FO had 11279 hours thereof 1271 hours on the A380, the SO had 8153 hours thereof 1005 on type, the CC had 20144 hours thereof 806 on the A380 and the SCC had 17692 hours thereof 1345 hour on type.
Join Date: Oct 2008
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ATSB Pictures
Just released ATSB pictures of damage to OQA on news.com.au
(don't know if these have been posted here before)
Qantas A380 | Qantas Explosion | News.com.au
(don't know if these have been posted here before)
Qantas A380 | Qantas Explosion | News.com.au
ATSB Preliminary Report
Qantas continues to take the line that this was a "new engine" and thus responsibility rests elsewhere.
Looking at page 14 we see that the engine has 6,314 hours in total and that it was removed in August 2009 and repaired in a Singapore workshop. I am not implying that repair was in any way related to the QF32 uncontained failure, as it sounds like a different area of the engine.
But I don't think that it is wise for Qantas to keep using the "new engine" defence when it has had that many hours and one shop visit.
Looking at page 14 we see that the engine has 6,314 hours in total and that it was removed in August 2009 and repaired in a Singapore workshop. I am not implying that repair was in any way related to the QF32 uncontained failure, as it sounds like a different area of the engine.
But I don't think that it is wise for Qantas to keep using the "new engine" defence when it has had that many hours and one shop visit.
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The flight data recorder shows, that engine #2's oil temperature and pressure values began to deviate from the other engine values 3:35 minutes after the aircraft became airborne. 37 seconds later the engine #2 N3 vibrations increase, the N3 indications fluctuate, 1 second later the N1 and N2 indications begin to decrease, N3 increases. 8 seconds after the vibrations began to increase N3 reaches 98% and started to reduce, engine #2 fuel flow reduces, N1 and N2 rpms decrease rapidly, a second later the overheat warning activates, another second later master warning and master caution illuminate, 2 seconds later (12 seconds after the vibrations increased) the turbine disk liberates at an altitude of 7250 feet evident by the failure of multiple systems at that point
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Why did the management systems not recognize these events (note the 37 seconds later!) and prevented further damage by shutting down the engine?
My reading of that para shows how short the timescale was of any indications of the problem, and no indication that any were "out of limits". I doubt you could even rely on the above quoted FE to notice these in that timescale, and pretty sure even if (s)he had noticed, no shutdown would have occurred prior the event.
NoD