Qantas A380 uncontained #2 engine failure
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It's an admission they need (and more specifically in this case) a flight engineer in the normal crew complement!
Someone that actually knows how the machine works, so as to reasonably suggest to the Captain the best course of action during non-normal procedures, and more importantly, during one of these really unusual events where in depth knowledge of the airplanes systems can sometimes be the difference.
They were really lucky during this one, even though there were multiple flight crew up the front, they were all of similar experience levels, that of the pilot!
Of course, the additional 'elephant in the room' with a flight engineer aboard, is the extra eyes and ears up front, something not to be taken lightly as some do.
Yeah, I know you all will scoff at this 'old world', 'outdated idea' sort of thing, but nevertheless, the more we progress into the modern world of computerized aircraft, the more we need someone that has some idea what is actually happening.
You know, I've really noticed during the recent years when two-crew airplanes have become more common, it's only the two-crew pilots that 'don't need' an FE, the prior three-crew pilots seemed to recognize their worth, and most would retain them if they had the choice!
EW73
Someone that actually knows how the machine works, so as to reasonably suggest to the Captain the best course of action during non-normal procedures, and more importantly, during one of these really unusual events where in depth knowledge of the airplanes systems can sometimes be the difference.
They were really lucky during this one, even though there were multiple flight crew up the front, they were all of similar experience levels, that of the pilot!
Of course, the additional 'elephant in the room' with a flight engineer aboard, is the extra eyes and ears up front, something not to be taken lightly as some do.
Yeah, I know you all will scoff at this 'old world', 'outdated idea' sort of thing, but nevertheless, the more we progress into the modern world of computerized aircraft, the more we need someone that has some idea what is actually happening.
You know, I've really noticed during the recent years when two-crew airplanes have become more common, it's only the two-crew pilots that 'don't need' an FE, the prior three-crew pilots seemed to recognize their worth, and most would retain them if they had the choice!
EW73
Sky News - take it as you will - is reporting that the presence of the extra crew members on board played a significant role in bringing the situation under control. Quite what that infers, I'm not sure.
barit 1
Yes, I see. May I direct your attention to the "pocket" (seen in section only) that surrounds the aft bearing on three sides? It is comprised of the Shaft on one side, the "Fin" of the IPT, and an "L" shaped "ring" ? The Turbine appears sandwiched in between these shaft/shaft sections. It is in this portion of the Wheel/Shaft mate that I percieve the "Splines" to be located. Showing the Wheel as separate in this view, there can assumedly be no other way to locate the Joint. This is then where the accelerated wear must have occurred, and seemingly the only avenue for Oil to escape.
Am I making sense here?
Yes, I see. May I direct your attention to the "pocket" (seen in section only) that surrounds the aft bearing on three sides? It is comprised of the Shaft on one side, the "Fin" of the IPT, and an "L" shaped "ring" ? The Turbine appears sandwiched in between these shaft/shaft sections. It is in this portion of the Wheel/Shaft mate that I percieve the "Splines" to be located. Showing the Wheel as separate in this view, there can assumedly be no other way to locate the Joint. This is then where the accelerated wear must have occurred, and seemingly the only avenue for Oil to escape.
Am I making sense here?
Bear, it is OK to ask the questions, but where your posts leave a little to be desired is where you start to draw conclusions.
As posted above there is not enough detail to draw any of your conclusions.
Its not my picture by the way - it was posted earlier by another in the thread above - it is quite interesting though. My only observation is that RR appear to have done a good job, on a 6m long engine, of keeping the number of required bearings to a minimum.
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I don't know of a single airline pilot who wouldn't want a flight engineer on the flight deck, especially in the event of an emergency. I think you are mistaken if you feel pilots think F\Es are "old world" and "outdated". The only people who object are accountants.
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Here Here
Can think of many a good pilot who had is arse saved by the trusty FE
I also think that all A380 operators are looking closely at how the crew performed and where the SOP's were lacking.
Experience may be a good teacher. but she is also very expensive way to go.
The more that comes out about this situation the better controled will be the future operations.
Its about time that business's that have a safety element in its production or operations got rid of the dabling bean counters.
Regards
Col
Can think of many a good pilot who had is arse saved by the trusty FE
I also think that all A380 operators are looking closely at how the crew performed and where the SOP's were lacking.
Experience may be a good teacher. but she is also very expensive way to go.
The more that comes out about this situation the better controled will be the future operations.
Its about time that business's that have a safety element in its production or operations got rid of the dabling bean counters.
Regards
Col
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What do you think a flight engineer could have done better than 5 pilots ?
There are no more CBs left in the cockpit ! You can restart some of the computers.Nothing else to improve the situation.
Acting on more of 1000 CBs is via a computer and inhibited in flight.
Remaining old fashioned CBs are located in the lower avionic bay and in the upper emergency bay.Checked the FCOM abnormal/emergency procedures and found not one item telling you "open the hatch,walk into
bay xy and pull CB xy"
So for what reason you want an engineer on board ?
There are no more CBs left in the cockpit ! You can restart some of the computers.Nothing else to improve the situation.
Acting on more of 1000 CBs is via a computer and inhibited in flight.
Remaining old fashioned CBs are located in the lower avionic bay and in the upper emergency bay.Checked the FCOM abnormal/emergency procedures and found not one item telling you "open the hatch,walk into
bay xy and pull CB xy"
So for what reason you want an engineer on board ?
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no-hoper
While I have yet to crew an aircraft requiring a FE, one might think that the additional systems aware crew member could have handily assisted an already resource-strapped flight deck crew once the EICAS/ECAM began spewing forth multiple bad news messages willy nilly.
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IP spool spline joint
IP spool spline joint, random thoughts. On the web there is a very good large format coloured picture of the Trent 500. On it you can see what apprears to be a splined joint adjacent to the most forward of the three thrust bearings. And there are ramp and notch features on it. I would assume that the spline is there so that the engine modules can be separated at that location. It may also function as a thermal expansion joint but there must be a way to transfer axial loads between the coupled shaft sections – perhaps the splines are shaped in a special way – helical spline joint coupling possibly.
I have mentioned before that it is unclear that the spline wear thing and the recent oil leak and fire thing are connected.
I have mentioned before that it is unclear that the spline wear thing and the recent oil leak and fire thing are connected.
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So for what reason you want an engineer on board?
When I look at a new 2-man cockpit and then an old flight engineers panel, I have to ask where did all that go. Sure that is now all controlled by onboard computers. But a computer can not reason. A computer can not think outside the box.
If there was an engineer with his panel on the Qantas A380 maybe he could have figured out how to shut down the No. 1 engine!
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Bearfoil,
The brown ring I would estimate is in the region between the IP and HP compressors.
I think the ball (thrust) bearings go LP, IP, HP from front to back. The LP shaft coupling seems to be slightly forwards of the LP thrust bearing and the IP shaft coupling slightly rearwards of the IP thrust bearing (in the same region as the brown ring?).
The brown ring I would estimate is in the region between the IP and HP compressors.
I think the ball (thrust) bearings go LP, IP, HP from front to back. The LP shaft coupling seems to be slightly forwards of the LP thrust bearing and the IP shaft coupling slightly rearwards of the IP thrust bearing (in the same region as the brown ring?).
I think this is the photo you refer to:
I don't think you can draw any conclusions about fire etc. from the coloration of the shaft.
Looking at this again...
...you can see the collocated HP and IP rear radial bearings would be completely sheilded from the LP shaft by the IP shaft. Hence if there were an oil fire here there would be no evidence on the LP shaft in the photo.
There is too little information here in the drawings and photos to draw any definative conclusions.
I don't think you can draw any conclusions about fire etc. from the coloration of the shaft.
Looking at this again...
...you can see the collocated HP and IP rear radial bearings would be completely sheilded from the LP shaft by the IP shaft. Hence if there were an oil fire here there would be no evidence on the LP shaft in the photo.
There is too little information here in the drawings and photos to draw any definative conclusions.
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I would say that the front LP bearing is mounted on the IP shaft so that the axial load that goes through the first bearing goes through the second bearing as well. In other words the IP bearing carries load from both the LP and IP shafts but the front bearing only carries the LP shaft load. It is not possible to have two thrust bearings connected by a single rigid shaft otherwise they fight each other.
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Hi all,
Not in an attempt to criticize the Quantas crew decision to wait that long before coming back to land (despite the uncertainty about the extent of the damages that impacted the wing structure) but to understand it, I was wondering if, amongst other reasons, it was partly due to the overweight which implied, added to the other failures, a landing distance required greater than the landing distance available.
Would someone know the LDR for an A380 that woulg return to land for a serious emergency (say an uncontrolled cabin fire e.g.) after a take-off at MTOW? And what would be the LDR at MLW ? To keep it simple, let's take a dry runway, at sea level, ISA and nil wind
Thanks
Not in an attempt to criticize the Quantas crew decision to wait that long before coming back to land (despite the uncertainty about the extent of the damages that impacted the wing structure) but to understand it, I was wondering if, amongst other reasons, it was partly due to the overweight which implied, added to the other failures, a landing distance required greater than the landing distance available.
Would someone know the LDR for an A380 that woulg return to land for a serious emergency (say an uncontrolled cabin fire e.g.) after a take-off at MTOW? And what would be the LDR at MLW ? To keep it simple, let's take a dry runway, at sea level, ISA and nil wind
Thanks
JFZ90
Isn't your conclusion that definitive conclusions can not be made, directly following a definitive conclusion drawn from the selfsame Pic?
Isn't your conclusion that definitive conclusions can not be made, directly following a definitive conclusion drawn from the selfsame Pic?
firstfloor
The Thrust from the LP Shaft is unidirectional, aft (by the pic). The IP Shaft can Thrust in both directions, hence its "capture" on both sides of each TB. ??
The Thrust from the LP Shaft is unidirectional, aft (by the pic). The IP Shaft can Thrust in both directions, hence its "capture" on both sides of each TB. ??
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727 spirit
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the LPT in diameter is smaller than the fan, so it must produce higher forces.
Pushing the LP shaft backwards.
Pushing the LP shaft backwards.
Just follow the forces
What you may actually mean is that in order to provide the torque needed by the fan due to smaller diameter the tangential forces on the turbine have to be higher than those on the fan. There is however no direct relationship between those tangential forces and the longitudinal forces on the shaft.
If this was true, then the LP compressor/shaft/turbine combination wouldn't produce any net forward thrust, and the fan would be useless (actually it would be producing drag!). The LP shaft is in one way or another anchored (via the thrust bearing) against the engine case, so if it actually pulls backwards as a whole, it pulls the engine case backwards and the aircraft it is attached to with it.
Just follow the forces
What you may actually mean is that in order to provide the torque needed by the fan due to smaller diameter the tangential forces on the turbine have to be higher than those on the fan. There is however no direct relationship between those tangential forces and the longitudinal forces on the shaft.
Just follow the forces
What you may actually mean is that in order to provide the torque needed by the fan due to smaller diameter the tangential forces on the turbine have to be higher than those on the fan. There is however no direct relationship between those tangential forces and the longitudinal forces on the shaft.
Its good here isn't it.
