QANTAS A380 Uncontained failure.
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The engine protection system is incorporated into the EEC. Its hardware performs the following functions:
LP and IP Rotor Overspeed protection...
LP and IP Rotor Overspeed protection...
But as we have previously discussed, a rapid N2 unspooling without like N3 change is indicative of mechanical failure (e.g. IPT detaching), and there seems to be the potential to "catch" this in the software before destructive overspeed occurs. In QF32's case, there is an apparent six-second window.
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Bear, thanks for the explanation of the EEC logic for a three spool engine.
Is this common on all three spool engines or unique to the Trent 900? It seems rather odd to me but I don't profess to understand the EEC logic on a 3 spool design.
The EEC settles on Fuel flow by sensing the RPM of the N3 ONLY. This seems counterintuitive, but may circuitously explain why the engine, at the threshold of Burst, was given additional Fuel.
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N3 Speed is furnished by the dedicated Alternator, which is powered through the gearbox by the HP Rotor. Two separate single Phase N3 windings supply N3 speed to each of the two channels in EEC. EEC utilizes this data to monitor speed, control the engine, and sense N3 Overspeed.
If there is a total loss of Shaft speed signals, EEC generates a "synthesized pair of shaft speed signals" (N1 and N2) for the cockpit, and uses N3 actual to "maintain transient Control." Turbine D, this is book on the TRENT 900, the others, I do not know.
If there is a total loss of Shaft speed signals, EEC generates a "synthesized pair of shaft speed signals" (N1 and N2) for the cockpit, and uses N3 actual to "maintain transient Control." Turbine D, this is book on the TRENT 900, the others, I do not know.
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The Video
Here we go...you will like this...
Captain Fantastic
Hell of a mess that engine made.
Holes all over the place.
Shame the Bayesian sophists were not on the 'plane.
This is as far as I go with this unless we get yet more WET replies.
This is where I and the BABUSHKA drive shafts of RR say a final goodbye.
Captain Fantastic
Hell of a mess that engine made.
Holes all over the place.
Shame the Bayesian sophists were not on the 'plane.
This is as far as I go with this unless we get yet more WET replies.
This is where I and the BABUSHKA drive shafts of RR say a final goodbye.
Last edited by DERG; 15th Feb 2011 at 10:22.
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Unlike some of the posters that imply that only the stockholders, investors, regulators and potential customers be satisfied, I believe the users, the paying passengers besides the flight crews also need to be completely assured of the safety after a near catastrophic event, such as this one, that occurred.
As to assurances, as pax, yes they would be nice, but I'd rather they didn't bother assuring me that the issue was fixed if, in fact, it isn't. From what's been discussed on this often fascinating thread, I'm not sure it is fixed, yet.
With an investor hat on, I think my biggest concern would be that even if the current AD regime has plugged the safety gap, how are RR making a profit on PBH contract on an engine that only does 70 cycles on the wing ? If the engine is safe but it and its contracts become a financial millstone round RR's neck, then it's no better for the company.
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It's all good
I see your vintage here on PPRuNe is about the same as mine. Funny, what drew me in was another TRENT goof. I still don't see any satisfaction re: the "Mystery Fuel" on BA038.
It is par for the course that given enough time, and sufficient urgency to travel, SLF pick up their carry-on, there teeny bottles, and launch. It truly is a safe way to mobilize, and it is also par for accident/incident threads to start loud, and end with a whimper.
Such is life in the big world of air travel. It isn't as safe as it could be, but it is very very safe, for all that. The sand in the knickers is it could be better. It is shy of the mark for defensible reasons, but I have never thought money should be in there, anywhere. Not even if facing Banko, as RR may well be. They have chosen the standard path, the way of least complaint, the way of wink and a nod with people who should be a bit more stern with the Corpos.
Nothing will ever diminish the level of sheer disaster QF32 faced that day in November. Nor will anything bring back the folks aboard AF447. We are entertaining mechanical doo doo, but Pilot Error is in there as well. Used to be, a Captain could tell Juan Trippe to pound sand, and date his wife on top of it. There was a goofy obeisance to, you know, authority.
Now, accountants dress in Pound Notes, or Franklins, and call themselves boss.
What utter bull****.
It is par for the course that given enough time, and sufficient urgency to travel, SLF pick up their carry-on, there teeny bottles, and launch. It truly is a safe way to mobilize, and it is also par for accident/incident threads to start loud, and end with a whimper.
Such is life in the big world of air travel. It isn't as safe as it could be, but it is very very safe, for all that. The sand in the knickers is it could be better. It is shy of the mark for defensible reasons, but I have never thought money should be in there, anywhere. Not even if facing Banko, as RR may well be. They have chosen the standard path, the way of least complaint, the way of wink and a nod with people who should be a bit more stern with the Corpos.
Nothing will ever diminish the level of sheer disaster QF32 faced that day in November. Nor will anything bring back the folks aboard AF447. We are entertaining mechanical doo doo, but Pilot Error is in there as well. Used to be, a Captain could tell Juan Trippe to pound sand, and date his wife on top of it. There was a goofy obeisance to, you know, authority.
Now, accountants dress in Pound Notes, or Franklins, and call themselves boss.
What utter bull****.
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infrequentflyer789
Yes, as an investor, there is a big concern. First, to develop a new engine, certify it, and then put it on the wing of a new aircraft being certified usually involves an investment of $2B US. And then, the first engines are usually sold at a loss as you are not far enough down the learning curve to produce a profit. Then there is the matter of how big the program will be (there is competition), e.g., a large number of engines over a long period of time. And finally there is the matter of the "Total Care" program.
The engine service program (Total Care) is really (should be) the big money maker but it is based on an actuary type system, the expected performance of the engine in the field over a time period before significant servicing, repair or replacement parts are required. These contracts typically are 10 years or more and the amount charged per engine to the airlines doesn't go up much over time to cover the cost of a bad start.
So with the problems at the moment, there is a significant setback of the new engine sales break-even point and the service end of the business is getting hit with costs that were not expected. Both are negatives on the bottom line.
There is always the possibility that when all costs are added up and the program doesn't produce enough profitable sales in the long run, the money lost will never be recovered.
With an investor hat on, I think my biggest concern would be that even if the current AD regime has plugged the safety gap, how are RR making a profit on PBH contract on an engine that only does 70 cycles on the wing ? If the engine is safe but it and its contracts become a financial millstone round RR's neck, then it's no better for the company.
The engine service program (Total Care) is really (should be) the big money maker but it is based on an actuary type system, the expected performance of the engine in the field over a time period before significant servicing, repair or replacement parts are required. These contracts typically are 10 years or more and the amount charged per engine to the airlines doesn't go up much over time to cover the cost of a bad start.
So with the problems at the moment, there is a significant setback of the new engine sales break-even point and the service end of the business is getting hit with costs that were not expected. Both are negatives on the bottom line.
There is always the possibility that when all costs are added up and the program doesn't produce enough profitable sales in the long run, the money lost will never be recovered.
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Hi Turbine D
Appears you are one of the resident experts on engines. I understand the FAA's 2007's new ETOPS regulations require ETOPS certification even for four-engine airplanes if they will operate on ETOPS routes. I understand Boeing will be the first manufacturer to certify a four-engine airplane to ETOPS standards when it certifies the 747-8. I also learned from a book I recently read that Australia will require a similar certification for all airplanes including the 747, A380s in a few years. If so, reading your following comment:
Will this looming ETOPS certification further worsen the cost situation? Thanks for your expertise
Appears you are one of the resident experts on engines. I understand the FAA's 2007's new ETOPS regulations require ETOPS certification even for four-engine airplanes if they will operate on ETOPS routes. I understand Boeing will be the first manufacturer to certify a four-engine airplane to ETOPS standards when it certifies the 747-8. I also learned from a book I recently read that Australia will require a similar certification for all airplanes including the 747, A380s in a few years. If so, reading your following comment:
So with the problems at the moment, there is a significant setback of the new engine sales break-even point and the service end of the business is getting hit with costs that were not expected. Both are negatives on the bottom line.
There is always the possibility that when all costs are added up and the program doesn't produce enough profitable sales in the long run, the money lost will never be recovered.
There is always the possibility that when all costs are added up and the program doesn't produce enough profitable sales in the long run, the money lost will never be recovered.
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My old uncle was an elec engineer for WSTNGHSE/GE (dynamos/cmcl power) back in the 40s - 70s and, my-o-my, the stories, some hilarious, he used to tell about the bean counters v/v best engineering. Now, this latest discussion takes me back to his old words as well as reminiscences of my own revolving around an old axiom I sometimes used to hear in mx about aircraft returning to revenue just out of D Check.
Strange how theyd often suffer one or a half-dozen (sometimes big) grounding squawks right out of the box on their first revenue flight. Theyd sometimes wind up at some God forsaken downline station where youd have to send a half dozen guys, fix it or not, or get a waiver and crew together to ferry the thing to a place where it can be repaired.
The moral was something like, Theres never enough time or money to put it back together and test it right the first time, but, OH, YEAH, there was always plenty of both later on! Seems this sarcastic rule might be equally at home today within the hallowed halls of RR (or GE/Pratt/Snecma, etc) as well? I like to think not, at least not of the major safety compromising type... but then I think of my old uncle angrily grousing about beaner rule in the land of dynamo's.
Why I think maybe even Boeing corporate might be just a little upset with their own beaners now that weve witnessed all the "save a buck" international fiascos that have gone on in development and construction of that neat new airplane of theirs. So glad Im retired! LOL
Strange how theyd often suffer one or a half-dozen (sometimes big) grounding squawks right out of the box on their first revenue flight. Theyd sometimes wind up at some God forsaken downline station where youd have to send a half dozen guys, fix it or not, or get a waiver and crew together to ferry the thing to a place where it can be repaired.
The moral was something like, Theres never enough time or money to put it back together and test it right the first time, but, OH, YEAH, there was always plenty of both later on! Seems this sarcastic rule might be equally at home today within the hallowed halls of RR (or GE/Pratt/Snecma, etc) as well? I like to think not, at least not of the major safety compromising type... but then I think of my old uncle angrily grousing about beaner rule in the land of dynamo's.
Why I think maybe even Boeing corporate might be just a little upset with their own beaners now that weve witnessed all the "save a buck" international fiascos that have gone on in development and construction of that neat new airplane of theirs. So glad Im retired! LOL
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Unbalanced Rotors CF6-45/50
No sooner done with one unbalanced engine we move on to the next..
Recommendations without a MANDATE DIRECTIVE and of serious concern..in other words they can do as they please!
HEADS UP!
CF6-45/50
Note: This will test just how robust this site is to pressure from commercial interests at the expense of OUR Safety
"The first recommendation asks that the FAA require operators of aircraft equipped with a particular model engine to immediately perform blade borescope inspections (BSI) of the high pressure turbine rotor at specific intervals until the current turbine disk can be redesigned and replaced with one that can withstand the unbalance vibration forces from the high pressure rotor. The second recommendation asks the FAA to require the engine manufacturer to immediately redesign the disk. The NTSB issued an additional recommendation for a requirement that operators perform a second type of inspection and another recommendation related to the engine manufacturer regarding the installation of the replacement disk."
Document SB-10-20 May 27 2010. NTSB URGENT
More reading here:
Four Recent Uncontained Engine Failure Events Prompt NTSB to Issue Urgent Safety Recommendations to FAA @ AMTOnline.com Top News
and officail document here
http://www.ntsb.gov/recs/letters/2010/A-10-098-101.pdf
Recommendations without a MANDATE DIRECTIVE and of serious concern..in other words they can do as they please!
HEADS UP!
CF6-45/50
Note: This will test just how robust this site is to pressure from commercial interests at the expense of OUR Safety
"The first recommendation asks that the FAA require operators of aircraft equipped with a particular model engine to immediately perform blade borescope inspections (BSI) of the high pressure turbine rotor at specific intervals until the current turbine disk can be redesigned and replaced with one that can withstand the unbalance vibration forces from the high pressure rotor. The second recommendation asks the FAA to require the engine manufacturer to immediately redesign the disk. The NTSB issued an additional recommendation for a requirement that operators perform a second type of inspection and another recommendation related to the engine manufacturer regarding the installation of the replacement disk."
Document SB-10-20 May 27 2010. NTSB URGENT
More reading here:
Four Recent Uncontained Engine Failure Events Prompt NTSB to Issue Urgent Safety Recommendations to FAA @ AMTOnline.com Top News
and officail document here
http://www.ntsb.gov/recs/letters/2010/A-10-098-101.pdf
Last edited by DERG; 16th Feb 2011 at 08:27.
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DERG. Only last week you said -
And now?
Now as far as the claim that some of us are partisan, we are biased toward GE or RR..well I for one have learned enough on this thread to make an educated guess just which engine I would trust my life with.
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My life
Forget
Profound question yes. I think the better question would be which airplane would I be happy to see my loved ones board. Or indeed any form of transport where I personally have no control over the machinery.
If that journey had to made I would chose which operator, which airline I would trust. There are very few operators which I would avoid. Now you will be asking why the f
does he just not answer the question!
Would I trust the RR T900 as it stands as of now in use with the operators who use it. Yes I would. Would I trust the CF6-45/50 with the operators who use it as of today. No I would not.
As for the T972 in use with Qantas, given the fact that it is replaced..we hope..every 70 cycles and the fact that there are four units on each A388. Yes I would.
What aircraft would I use if I had a free choice for the places my family is most likely to visit? That would be the BAe 146.
Profound question yes. I think the better question would be which airplane would I be happy to see my loved ones board. Or indeed any form of transport where I personally have no control over the machinery.
If that journey had to made I would chose which operator, which airline I would trust. There are very few operators which I would avoid. Now you will be asking why the f
does he just not answer the question!Would I trust the RR T900 as it stands as of now in use with the operators who use it. Yes I would. Would I trust the CF6-45/50 with the operators who use it as of today. No I would not.
As for the T972 in use with Qantas, given the fact that it is replaced..we hope..every 70 cycles and the fact that there are four units on each A388. Yes I would.
What aircraft would I use if I had a free choice for the places my family is most likely to visit? That would be the BAe 146.
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As for the T972 in use with Qantas, given the fact that it is replaced..we hope..every 70 cycles and the fact that there are four units on each A388. Yes I would.
What aircraft would I use if I had a free choice for the places my family is most likely to visit? That would be the BAe 146.
What aircraft would I use if I had a free choice for the places my family is most likely to visit? That would be the BAe 146.
I am not sure what documentation you are reading BUT whom is changing engines every 70 cycles.
To mention a BAE146 in regard to reliabilty and safety.
( Bring Another Engine ) 146.
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Thanks for returning to thread Bolty.
So they are not changing the T972s evey 70 cycles. Right.
Maybe they have changed the "chip" to back to the T970 specs?
As far as the 146 goes, as long as you choose your seat well, I believe it will get you there.
Has the 146 had an uncontained engine failure?
So they are not changing the T972s evey 70 cycles. Right.
Maybe they have changed the "chip" to back to the T970 specs?
As far as the 146 goes, as long as you choose your seat well, I believe it will get you there.
Has the 146 had an uncontained engine failure?
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Maybe they have changed the "chip" to back to the T970 specs
As far as the 146 goes, as long as you choose your seat well, I believe it will get you there.
If I were to choose my seat well for a "fruit bat" (Oz name for a 146) flight it would be in the terminal waiting for another type aircraft. ( I am probably being overly harsh)
Amongst us engineering types the BAE 146 is the only aircraft you have to check the front and back for bird strikes if reported. Boeing 744 is my pick,
Back to Trent failures.
I have a recollection of Cathy grounding its fleet of RR powered A330s.
Something about an angle gearbox failing structurally due to out-sourcing poor quality control in machining.
The CEO of Cathy grounded all its A330s where ever they were in the world as it was unable to predict a life span of the engines as some engines failed at 3000 hours and some close to 50.
This is a vague memory from the 90s but it would appear this type of trouble has struck before.
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Very much appreciate your view Bolty. Thanks for rejoining the thread.
Note: A new thread has been started in the Tech Log about the CF6-45/50 URGENT subject.
The relation to the T972 failure is: HARMONIC EXCITATION LEADING TO UNCONTAINED ENGINE FAILURE.
This is the math used
http://www.aerostudents.com/files/vi...Excitation.pdf
My guess is that RR and Schaeffer were not communicating effectively while these numbers were entered into the design specs.
There was one or many breaks in communication within or without RR during the design process. This would suggest that the design itself is inherently flawed OR that the manufacturing process cannot be configured to reproduce the design specifications.
Only one way this can happen: non communication or incompetent management.
Note: A new thread has been started in the Tech Log about the CF6-45/50 URGENT subject.
The relation to the T972 failure is: HARMONIC EXCITATION LEADING TO UNCONTAINED ENGINE FAILURE.
This is the math used
http://www.aerostudents.com/files/vi...Excitation.pdf
My guess is that RR and Schaeffer were not communicating effectively while these numbers were entered into the design specs.
There was one or many breaks in communication within or without RR during the design process. This would suggest that the design itself is inherently flawed OR that the manufacturing process cannot be configured to reproduce the design specifications.
Only one way this can happen: non communication or incompetent management.
Last edited by DERG; 16th Feb 2011 at 15:35. Reason: additional
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Bolty McBolt
I believe DERG has quoted press releases that Qantas made earlier this year in connection with an affidavit at a court against RR. Reason beside many other items was the RR - information/recommendation/ mandation what so ever one may call it - that using the T972īs with 540 psi at p30 - as I understand the max. perm. TOP - would make it necessary to change engines - even "mod C " after 75 such cycles.
This information was posted in this thread before and untill now it has not come to public that this restriction was lifted.
So if you write that QF flies daily A 380 service to LAX that either implicates that these flight are narrowly controlled and after 75 cycles the mentioned engine change silently takes place, or there is another modification made on that engine - probably called "mod D" - that has eliminated the concerns that led RR to issue such a severe restriction.
Never the less in my opinion you`re sounding very confident - overconfident may be ?? - having in mind the fact that the spline AD is still valid and even the newest engines must be inspected after 200 cycles and follow on at 100 cycles. (s.a. EASA AD-No: 2010-0242 R1)
Could it be that the members of this net simply have missed an important change in regulatory paperwork for the daily usage of the RR T972 ??
This information was posted in this thread before and untill now it has not come to public that this restriction was lifted.
So if you write that QF flies daily A 380 service to LAX that either implicates that these flight are narrowly controlled and after 75 cycles the mentioned engine change silently takes place, or there is another modification made on that engine - probably called "mod D" - that has eliminated the concerns that led RR to issue such a severe restriction.
Never the less in my opinion you`re sounding very confident - overconfident may be ?? - having in mind the fact that the spline AD is still valid and even the newest engines must be inspected after 200 cycles and follow on at 100 cycles. (s.a. EASA AD-No: 2010-0242 R1)
Could it be that the members of this net simply have missed an important change in regulatory paperwork for the daily usage of the RR T972 ??
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Hi avgenie,
Having read through the new ETOPs plan for 3 or 4 engine aircraft, it seems to me that most of the responsibilities will be on the operators (airlines) that fly these long over water routes. Route planning and diversion planning becomes a more demanding issue than what it has been. I don't see it as a big cost item for an engine manufacturer unless there are unforseen problems that develop in revenue service.
For new aircraft/engine combinations, ETOPs is generally applied for and demonstrated during the certification phase. Since most airlines establish contracts for the aircraft and engines separately, I would bet there will be penalty clauses established should either fall short and the contracted ETOPs rating is not achieved or becomes reduced because of problems. This is where the bottom-line of either manufacturer could be impacted depending who has the problem and how long it takes to resolve it.
There is another large customer today, leasing companies. They buy airplanes and engines and lease them to various airline. Since these deals are very complex and vary considerably it is hard to tell how this change will affect them.
Having read through the new ETOPs plan for 3 or 4 engine aircraft, it seems to me that most of the responsibilities will be on the operators (airlines) that fly these long over water routes. Route planning and diversion planning becomes a more demanding issue than what it has been. I don't see it as a big cost item for an engine manufacturer unless there are unforseen problems that develop in revenue service.
For new aircraft/engine combinations, ETOPs is generally applied for and demonstrated during the certification phase. Since most airlines establish contracts for the aircraft and engines separately, I would bet there will be penalty clauses established should either fall short and the contracted ETOPs rating is not achieved or becomes reduced because of problems. This is where the bottom-line of either manufacturer could be impacted depending who has the problem and how long it takes to resolve it.
There is another large customer today, leasing companies. They buy airplanes and engines and lease them to various airline. Since these deals are very complex and vary considerably it is hard to tell how this change will affect them.
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Forgive me for repeating this post I made in the other thread on 3 December.
Believe me my question is NOT intended in any way to provoke any sort of argument because I am totally ill equipped to have an argument with anyone . But I do wonder sometimes if Rolls Royce make aero engines these days or just assemble them --they seem to buy in bits from all over the world. Does this strain quality control?
When I was a kid the impression was that they made everything -even all nuts and bolts--from alloys they made themselves in their own foundries. They had, it seemed, total control.
Who made the apparently crude oil pipe for them?
As I read the unfolding story on this thread this question of mine nags at me more and more. Is there inherent danger in buying in parts from all over the world instead of making them yourself?
And please can I ask another question?
Why do RR need so many different engines? It seems like every new plane has to have its own engine type. Someone on this or the other thread has already asked why RR do not replace the 900 on the A380 with two pairs of different proven reliable engines to give the same thrust.
Same as before I am not trying to stir anything at all. I am just SLF whose father worked at RR for 40 years in Experimental Dept at Sinfin.
Believe me my question is NOT intended in any way to provoke any sort of argument because I am totally ill equipped to have an argument with anyone . But I do wonder sometimes if Rolls Royce make aero engines these days or just assemble them --they seem to buy in bits from all over the world. Does this strain quality control?
When I was a kid the impression was that they made everything -even all nuts and bolts--from alloys they made themselves in their own foundries. They had, it seemed, total control.
Who made the apparently crude oil pipe for them?
As I read the unfolding story on this thread this question of mine nags at me more and more. Is there inherent danger in buying in parts from all over the world instead of making them yourself?
And please can I ask another question?
Why do RR need so many different engines? It seems like every new plane has to have its own engine type. Someone on this or the other thread has already asked why RR do not replace the 900 on the A380 with two pairs of different proven reliable engines to give the same thrust.
Same as before I am not trying to stir anything at all. I am just SLF whose father worked at RR for 40 years in Experimental Dept at Sinfin.
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You ask good questions, no apologies required.
I think the total vertical integration business model dates back to the start of mass production automobile manufacturing. In the US, Henry Ford had and made everything required to produce a car or truck in his own factory.
The same was true during the war years, both in the US and in the UK n the manufacture of aircraft engines. However, with the advent of the jet engine and the globalization or reach of businesses, the vertical model began to fall away. One reason might be specialization where smaller external companies invested both in technology and manufacturing capability to produce certain items of good quality and lower costs than what could be manufactured in-house. Larger companies were tempted to go outside for items as it saved financial resources that would be required to update equipment and manufacturing processes to remain cost competitive. In the end, only the most highly technical items and processes remain in-house. The less technical items can be purchased outside satisfactorily with good quality oversight and planning. Today, this has spread globally as business deals are made to sell product while some of the product content is made in the buyer's country. It does require a good quality organization worldwide and sometimes, on site daily depending on the product being produced. It is also important to have a good technical capability plan and assessment team in place to assure capability before orders are placed. So, yes, Rolls Royce, GE, Pratt & Whitney and others have become more focused on design and assembly of engines and less involved in actual parts manufacturing. The key to success is not skimping on quality oversight no matter where parts are produced.
I will answer the engine question in another post.
I don't know the answer to who produced the stub pipe, but I understand the latest engine revision doesn't have the stub pipe component at all.
You ask good questions, no apologies required.
But I do wonder sometimes if Rolls Royce make aero engines these days or just assemble them --they seem to buy in bits from all over the world. Does this strain quality control?
When I was a kid the impression was that they made everything -even all nuts and bolts--from alloys they made themselves in their own foundries. They had, it seemed, total control.
When I was a kid the impression was that they made everything -even all nuts and bolts--from alloys they made themselves in their own foundries. They had, it seemed, total control.
The same was true during the war years, both in the US and in the UK n the manufacture of aircraft engines. However, with the advent of the jet engine and the globalization or reach of businesses, the vertical model began to fall away. One reason might be specialization where smaller external companies invested both in technology and manufacturing capability to produce certain items of good quality and lower costs than what could be manufactured in-house. Larger companies were tempted to go outside for items as it saved financial resources that would be required to update equipment and manufacturing processes to remain cost competitive. In the end, only the most highly technical items and processes remain in-house. The less technical items can be purchased outside satisfactorily with good quality oversight and planning. Today, this has spread globally as business deals are made to sell product while some of the product content is made in the buyer's country. It does require a good quality organization worldwide and sometimes, on site daily depending on the product being produced. It is also important to have a good technical capability plan and assessment team in place to assure capability before orders are placed. So, yes, Rolls Royce, GE, Pratt & Whitney and others have become more focused on design and assembly of engines and less involved in actual parts manufacturing. The key to success is not skimping on quality oversight no matter where parts are produced.
I will answer the engine question in another post.
I don't know the answer to who produced the stub pipe, but I understand the latest engine revision doesn't have the stub pipe component at all.