Marketing v Safety then? Thanks for your rapid response.

bear

RR makes noise of its constant monitoring program. It is impressive on screen (video) but is essentially a real time ACARS, (shout out to AF447). With a minimum one minute lapse in sampling, it is about as helpful. Perhaps the profit is here, in the NEW, HIGH TECH! Power by hour format. Some of what was traditionally treated with serious professional scepticism has become marketing Fluff prior to proof.

bear

Anyone to support this view?
 

Why not put two T1000s inboard and two T800s outboard?

Ya know, that is not a bad idea. Wait, let's Roid 2, and 3, and eliminate 1, and 4, and .........wait, that's the 787.

No - derating increases engine life and higher power testing irons out problems earlier. :ok:

One hates it when hyperactive amateurs suffering from confirmation bias jump to conclusions beyond their competence or knowledge.:=

Good Nature
 

Hey we are trying to help RR out here...:)

Derate is identical to over-built. Shell makes excellent polymer, and adhesives, and used to do decent research in Emeryville. (:=)

(it was NOT easy synchronizing those fingers)

Derating also can be political; as such, it allows for "squishy" parameters, and "Test on Wing".

"Open 'er UP" can describe Throttle, and engine Case also.

bear

Price of Gas
 

:ugh:Gas costs $11 per US gall here in the UK.:ugh:

Yes DERG and Bearfoil, and those contributions are to this thread irrelavent like most of your posts.

'Trying to help Rolls Royce' - how arrogant is it possible to be?

I think ad hominem is not helpful, let's desist. Yes?

bearfoil;

RE "Test on Wing": You mean the thousands of hours and flight cycles accumulated in the AB flight test programme prior to entry into commercial service?

Engine Certification
 

DERG & Bearfoil
Design, Testing & Certification Requirements To Gain Engine Type Certification
I thought it might be interesting for you to see and browse the various requirements set forth by the US FAA to gain type certification for a turbine engine. Many of the questions being posed in recent posts are covered somewhere in this document. I would assume the European requirements are the same.

Electronic Code of Federal Regulations:

Also, there are Advisory Circulars that give guidance to specific topics. These are not mandatory as there may be other ways to demonstrate compliance to the specific topic. Examples are:

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/list/AC%2033-3/$FILE/AC33-3.pdf

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/list/AC%2033.14-1/$FILE/ac33.14-1.pdf

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/list/AC%2033.63-1/$FILE/AC33.63_1.pdf

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/list/AC%2033.27-1/$FILE/AC33-27-1.pdf

You will need to copy and paste the advisories into your browser to view them.

In another post I will talk more about modeling, analysis and monitoring.

Thank You Turbine D
 

I see the shell person has gone offline, you know we had a good run on here before that kind of intimidation. They actually have a USA 0800 nuber for bullies on line, but this web site is in the UK I think.

Maybe he knows the guy from QuinitiQ the " lube scientist" the former mine detection robotics salesmen.? Steve Lee he is called. Who knows?

Now too look at these new USA links. When I was searching Turbine it was notable that USA concerns readily accepted "modelling" as tool and not the exalted technique it appears to be overhere.

First Failure
 

The accident T972 did not comply with this for starters
http://rgl.faa.gov/Regulatory_and_Gu.../AC33.63_1.pdf

DERG

Yes, I noted the same thing (Shell Person). It's too bad some people play the "phantom" critic role and contribute nothing to the technical discussions of the day. :ugh:

HazelNuts39

"test on Wing". I think my comment was a bit flippant, I did not mean there was an actual recognized and formal test. I meant to characterise what some may see as a "De Facto" situation. A regime of rigid inspections enforced in an attempt to "monitor" known and potentially disastrous "unknown" conditions. The potential for disaster is patent in EASA's description of the "conditions". Down to a ten cycle inspection, known and very troubling wear could result in "Loss of the Aircraft".

I remain troubled by what I see as distraction; an attempt to sever the "Oil Pipe" fiasco from the AD, a "May have resulted in..." going unaddressed (at least here), and data and comment by the manufacturer at fault taken at face value.

Perhaps I am completely off base. There may be too much discussion? I am simply mystified at some of what I am reading, and by the apparent lack of concern. This flight came within a speck of going down, and for reasons that were addressed by AD's in an ongoing and co-operative manner for an entire year.

Shell Management:

Spot on, SM. Almost every OEM has done it, or has wished they had.


NO! I don't see any of that on this thread, do you? :rolleyes:

On another thread there is mention of adding Shell Person to ones 'ignore list'. I just did that. Oh, and I added one other also. :O

Modeling, Analysis & Monitoring
 

DERG & Bearfoil

Modeling & Analysis

Today, every unique component in a new aircraft engine is designed using a 3D modeling program. There are no longer masses of 2D blueprints produced (except for special requests). 3D programs such as Unigraphics or Catia are widely used in the aircraft business. Upon completion of the component being designed on the computer, the electronic files are saved and passed on for various purposes to various entities:
1. In-house analysis groups that determine the designed component's suitability in meeting the various parameters basic to the design, e.g. fatigue life, vibratory stress limits, temperature parameters, weight limitations, etc.
2. Suppliers that will produce the basic component, casting, forging, inspection gauging, etc., who in turn will forward the electronic data to their suppliers that build the tooling that will produce the component.
3. Manufacturing Centers that will machine the components where the electronic data is programmed into the units that will be used to machine, produce and inspect the final product.
So modeling is today's way of life and it has reduced the number of mistakes that were common in the past. It is not to say there are not pit-falls, there can be as Airbus found out on the A-380 program. In their case, although one common program (Catia) was used to design the electrical wirings system for different sections of the fuselage, two different version were used and when it came time to put the sections together, the electrical wiring didn't go together causing a ~2 year delay.
So if you model every component in a turbine engine, is it possible to assemble all the components together on the computer to see what the engine looks like in total? Why yes it is and it has been done. Then, is it possible to look at the engine on the computer and run it and perform dynamic analysis of vibrations, pressures, temperatures, transient conditions, clearance controls, SFC, etc? Well, yes but, some things have to be done first. Since many of the analysis programs were developed at different times, the codes used do not mesh together at all. So if the individual codes were to be redeveloped using a common code an actual engine can be put through its paces on the computer while checking key metrics and engine behavior characteristics. Mind you, this can be all accomplished without buying or producing any physical parts. This is the direction engine design and manufacturing is headed, if not already there at this moment.

Monitoring

Aircraft engine producers have known for sometime that the money (profit) is not in the sales of the original engine (often they are sold at cost or below cost early in the program), but in the subsequent sales of spare parts or replacement parts. Today it takes an investment of $2B to develop and certify a new large turbofan engine and it takes a long runway program to break even. In the meantime, airlines worldwide struggle to make money with the ups and downs of fuel costs and revenue passengers in ever changing economic times. To cut costs, many have disbanded their engine overhaul shops and therein lies a new business for the OEM's, provide this service. To do it right, real time engine monitoring is a necessity to set realistic fees to provide this service (Power by The Hour, Total Care, whatever). And so you will see increasing levels of realtime downloading of engine operating parameters (as many as a hundred or more parameters) to both the airline and OEM's appraised of operating conditions while working together to keeps the engines performing and in the air, out of the overhaul shops as much as possible, a win-win situation for everyone.

This is how I see the engine business going forward in today's computer driven world.

I see
 

Yes I see clearly that will be the reality.

In my book this failure was something out of 100 year old accident report, something you would dig up in a mouldy old "Mechanical Eng Failures of 1911"

Whatever was the cause there was a HELL of a breakdown in communications and respect between the different parts of RR. and Airbus. They spent 15 months flight testing alone.

The fact that we have only TWO main supliiers viz GE and RR does not, in my view, help the civil aerospace industry. The fact that we have TWO sets of environmental protection targets to meet does not help.

The EADS set up in my view has many other cultural/language problems to over come as you highlighted with the simple connector variance.

Unlike MIT which is very much an egalitarian our top academic facilities are distant from reality, insular and less approachable. Our military facilities in Europe have been decimated and in that process we lost many skills that so could easily prevent this accident.

I'm tired. If the shell person comes back tell him I use pure virgin olive oil in summer and mix it with a little kerosine in winter. That usually is enough to move 'em on.:E

commotion
 

Was a bit on "idle" for a while. Now I have a problem to cope with all the scientific and engineering entries. But what now I have clearly in mind is, all that is necessary to make a new engine running as planned and predicted and sold to a customer is at place, ready to be adopted and used. Or not ??
Like to quote DERG first.
quote:
Whatever was the cause there was a HELL of a breakdown in communications and respect between the different parts of RR. and Airbus. They spent 15 months flight testing alone.

Very correct !! But what makes you believe they also tested engine vibration in flight ??? What would you say if that wasn´t done probably since the very early RB 211´s or the Trent 500´s ?? What if there already some results came to be known and set aside because they didn´t "fit" the economical targets ? Probably also the pride of some desighners or engineers ??

I know, these are very hypothetical remarks and questions. But imagine if my blind shots turn out to be point hits !!
If that would be true, no silly oil stubb problem or bearing chamber vent or support structure enforcement would help. It ends in something that we might see in about 15 - 18 month, if everyone works as expected.

Perhaps if the hyperbole, conjecture, accusations and outright drama could be toned down or even dispensed with, this might become an interesting thread. As it is there's a whiff of Jerry Springer about it.

That certain participants set out from a conclusion rather than attempting to arrive at one, doesn't do much for quality either.

computer modelling
 

There is always the possibility of modelling a complete engine, but in my experience in another field total modelling is not always helpful and indeed can be misleading. I found computer models to be very helpful when applied in smaller ways that permitted understanding of the results, in the same way that simple maths provides a better understanding than a complete math model. The models are always to some extent idealised and I doubt whether vibrations could be effectively modelled because there are so many random elements to include. And random is difficult for computers because they suppose that random is actually random whereas in reality it is not, a Monte Carlo type programme is drastically over-pessimistic when compared with other engineering techniques such as rss, which allows for the statistical improbability of everything being on the very worst limit in any one product.

With apologies for uk english spelling.

DERG wrote under the header First Failure as follows, today at 12:38:

This is a 15-page document. Four pages in at paragraph 2.3.c there seems to me to be a failure to comply, in the matter of the spline damages. The AD's concerning this problem seem to identify it as having the potential to cause uncontained failure of major components of the turbine engine. The AD's further prescribe a program of extensive and frequent inspections, which at one time were down to every second cycle. What is the margin of safety in an every second cycle inspection program? Or for that matter, in an every 20-cycle inspection program-- is this the current revised inspection frequency possible under that program? (I'm having a little trouble keeping up, the changes come so fast.)

In any case, this handling of this spline problem appears to be either an "Engine design or operating restriction(s) that allow(s) and manage(s) accumulation of high-cycle fatigue damage for [a] component, [which is] not acceptable if the failure of that component would cause a hazardous engine effect. ..."

This would appear to preclude the operation of the Quantas 380's as now configured into LAX. I note that Qantas' appears to have no intent of doing so.

Have I missed something?

OE

OE,

As I understand it, Qantas cannot fully utilise the A380 out of LAX as it did before the failure. RR is only allowing a derated engine at the present.

Mike

"Very correct !! But what makes you believe they also tested engine vibration in flight ??? What would you say if that wasn´t done probably since the very early RB 211´s or the Trent 500´s ?? What if there already some results came to be known and set aside because they didn´t "fit" the economical targets ? Probably also the pride of some desighners or engineers ??"

Oh I think they tested vibration OK during the 15 months. But I bet the test engines were EAs or 970s not 972s. Humanity is far from perfect I agree.

"This would appear to preclude the operation of the Quantas 380's as now configured into LAX. I note that Qantas' appears to have no intent of doing so."

Qantas depended on getting an A388 that was fit for the purpose. They have to operate the A388. The B74 fleet is being over worked as it is trying to fill the gap. Qantas is not the culprit.

"Perhaps if the hyperbole, conjecture, accusations and outright drama could be toned down or even dispensed with, this might become an interesting thread. As it is there's a whiff of Jerry Springer about it."

You hit the nail on the head. Confrontation with the truth and dealing with issue. Nothing more dramatic than a plane with 469 people on it circling around while the pilots try and work out why the engine exploded.

This thread seems interesting enough for the many visitors who come here. Rolls Royce were incompetent in so many ways way above the level of Jerry Springer, a documentary media program more akin to the Discovey Channel would be appropriate.

Ther is always Al Jahzeera, they did a good job digging out the B737 build fiasco.

Old Engineer

Good to have you back! It has been awhile since your last post, must be the winter weather...

I thought it would be interesting to post the certification requirements as presented in the US FAA regulations. You have noted a particular item that stands out and DERG did the same. I am sure there are more that seem applicable. As I see it, the OEM (original engine manufacturer) meets with the government regulator and submits a process for certifying a subject engine. During that meeting or subsequent meetings, it is decided exactly what the requirements will be for certification. Is it a totally new engine? If so, it requires all of the steps outlined for approval. Is it a derivative engine or growth engine from an existing family? Well, maybe this will be required but this will be waived based on history. And then the certification process begins and proceeds to engine type certification. Keep in mind that even if you go through a flight demonstration program on a different aircraft and a 150 hour endurance demonstration in a test cell, not all the potential problems may have surfaced or have been wrung out. So then, the engine receives its type certification, deemed to be flight worthy, and is ready for the real application, lets say on the A-380 aircraft.

The aircraft certification program is focused on the aircraft, although the same regulatory agency is in charge, just a different set of people and expertise are highly involved. So then, if during this aircraft certification program there are engine abnormalities along the way, how are they handled? What if there are, during the course of flight testing (1-2 yrs.), an abnormal number of engines removed off wing for various unnamed problems, beyond planned engine removals? Assume a significant number. Where do responsibilities rest, with the OEM, with Airbus, with the governmental regulatory agency? How was it handled? In my mind, this is where the breakdown occurred on the 900 and A-380. It wasn't during the original engine certification process, except for possible should have done but didn't possibilities. There was a lot of pressure by the producers to deliver the goods to the customers as the program was significantly behind schedule, viability of businesses rode on a favorable outcome of the flight test and aircraft certification program, so how were technical problems with the engines handled by the regulatory agency during the aircraft certification phase? I will let this up to the individual's imagination, I have mine.

Turbine D

The Key Document Faa A.c. 33.63-1
 

http://rgl.faa.gov/Regulatory_and_Gu.../AC33.63_1.pdf

OLD ENGINEER
Much appreciate your help here. The link you posted up in #357 did not connect so I reposted it.

The clue to the failure of the T1000 test on Aug 4 2010 is in this document.

U.S. Department of Transportion FAA ADVISORY CIRCULAR of July 25 2007 initiated by ANE-10. Adivisory Circular # 33.63-1

DERG, If you wish to selectively quote from
The Key Document Faa A.c. 33.63-1, then perhaps you should also give consideration to paragraph 2b. on the first page. ie.
I should think that TCDS NUMBER E00075EN is the FAA's position on the Trent 970/972 engine.

However , if it happens that you are on the FAA board, then please accept my apologies.

mmciau,30 Jan 2011.Wrong. The majority of QFA 380's are cleared for Full Power Take-offs out of KLAX or anywhere. This I know, from 1st hand experience.

TRENT972

Keep reading your referenced selection. 2b is a rough reiteration of the Authority the FAA exerts on compliance issues. It is essentially a "Heads Up" to the applicant.

It is a statement for clarification, and as such leaves purposeful and narrow openings for latitude in following the process. If you know dogs: Not a "Collar", per se, but a "choke chain".

Advisory? Absolutely. Also a SUPERVISORY. The FAA hasn't the equipment or the talent the manufacturer does, so the FAA allows the Company to do all the research and development. Also, of course, the manufacturing of components.

If you know flying: "Pull Up, Terrain".

TRENT Cleared by whom?

Trent 972
 

Thanks for that. I am not on the FAA board. I think the engineering is relatively simple when you compare it to the social structures that gate keep the blaming and shaming.

Why are some flights on QFA12 done with B74s?

Bearfoil, you will note that the TCDS NUMBER E00075EN predates Faa A.c. 33.63-1

Quote:

---

It is essentially a "Heads Up" to the applicant.

---

What applicant? Certification was already accepted. That horse had already bolted.
To argue that the development of the engine could comply with an advisory standard (that may have already been completed to an acceptable alternative) after FAA acceptance of the Trent certification, is an unworthy argument.

Quote:

---

TRENT Cleared by whom?

---

1.Rolls Royce
2. QANTAS
3. The Aircraft Flight Manual
4. Airbus FCOM
5. Me, as I pushed the Thrust Levers to TOGA on take-off out of LA, recently.

If you know flying "Pull your head in" - but I doubt you will.

Bearfoil: OMG ! Now, THAT is funny! :}

Trent 972
 

Why are some flights on QFA12 done with B74s?

DERG, I'm not a scheduler, so I can't answer that question. My best guess is that it takes about 40 hours for a 380 to do a SYD or MEL - LAX return flight and we don't have enough 380's to operate 2 daily by 7 days a week, services to LAX, as yet. (and keep them on the SIN/LHR flights as well)

Trent972

Much Respect, Captain, F/O. I have to assume then that all the Authorities are satisfied. I don't see any listed as to compliance with The Certificate as regards unlimited operation. AD? Certainly you missed the most important ones, the FAA 337 or waiver? Share with us the Mechanicals?? Loads?? Calcs?? Limits??

Head withdrawn into Carapace.

bear

Bear, The ol' FAA 337 - wherein one must
Now which A380 sports an American N registration? Bueller, Bueller ....Anyone?
The answer to your last question is commonly known as MOD C (all 4 engines)- no restrictions to use of.

Trent 972 At least some of us understand what you are saying. Thanks!:ok:

Of course some others contributors are overspeeding, beyond their fatigue life...:uhoh:

Cosy Relationships
 

Bear...going back to your theory of group think. It seems the FAA and the EASA rubber stamp each others work. The FAA relies on the data produced by RR because it has been approved by the EASA.

As TURBINE D asks
"Where do responsibilities rest, with the OEM, with Airbus, with the governmental regulatory agency? How was it handled? In my mind, this is where the breakdown occurred on the 900 and A-380".
and

"viability of businesses rode on a favorable outcome of the flight test and aircraft certification program"

No business had more to loose than Qantas. The SIA CEO has made noises last week wanting an answer from RR, he is a very patient man in my opinion.

I don't think the ATSB has the resources to nail down if this was a design fault in the T900 series itself but I do expect the ATSB to report, without any regard to the happy relationship the FAA has with EASA or RR or anybody else.

It could well be that RR cannot balance this T900 and the misbored pipe did it us a big favour.

As TURBINE D states:

"so how were technical problems with the engines handled by the regulatory agency during the aircraft certification phase? I will let this up to the individual's imagination, I have mine."

If the failure was due to a faulty oil pipe..then fine.

Shell Management
What oil do you recommend for the 180C mean temps in this T972?
Maybe you have an additive?