QANTAS A380 Uncontained failure.
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I suspect that if your location (Seattle) is accurate, you may very well be an RR employee, on assignment at Boeing, probably in support of the Trent 1000 on the Boeing 787. A clue is your use of the word "rubbish". In the States, we seldom use this word, but the word "refuge" or more commonly, "garbage".
With over 2500 posts, this thread is in reaction to a very, very near tragedy on the Qantas Airbus A-380 given the catastrophic failure of the Trent 972 engine. It is also a reaction to Rolls Royce's response to this event. The silence from Rolls Royce has been deafening.
Some of us have been in this aviation business for all our working careers in one role or another and because of the deafening silence from Rolls Royce, we speculate as to the cause/causes of this Trent 972 failure, whether or not there were specific indications that such a failure would eventually transpire, and whether or not corrective actions have actually taken place that don't require repeated inspections at short intervals among other things.
So, this thread is what it is, like it or not from your perspective. You can contribute but perhaps that may not be in your best interest, so the "silence is deafening" route may be your best alternative.
With over 2500 posts, this thread is in reaction to a very, very near tragedy on the Qantas Airbus A-380 given the catastrophic failure of the Trent 972 engine. It is also a reaction to Rolls Royce's response to this event. The silence from Rolls Royce has been deafening.
Some of us have been in this aviation business for all our working careers in one role or another and because of the deafening silence from Rolls Royce, we speculate as to the cause/causes of this Trent 972 failure, whether or not there were specific indications that such a failure would eventually transpire, and whether or not corrective actions have actually taken place that don't require repeated inspections at short intervals among other things.
So, this thread is what it is, like it or not from your perspective. You can contribute but perhaps that may not be in your best interest, so the "silence is deafening" route may be your best alternative.
Oh and whilst at it read the economist article and see what they feel about RR silence. I'm not convinced that I agree that RR should have been as silent as they have been but the aerospace industry appears satisfied.
The investors need only seek out technical based opinions beyond this from independent experts.
Since such experts are not in evidence in this thread (name, title, bio) then the technical design-redesign opinions expressed here are only to impress the browsing reader.
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U415967
'Having spent sometime reading this thread for the first time I am very disappointed by the amount of unsubstantiated rubbish that is spouted. RR have played this close to their chest publicly, but do any of you know what they have been doing with the airframers/airliners and authorities. Thought not.
Bearfoil, DERG, annex14 etc. some of the junk you are spouting as fact is unbelievably wrong. Anyone that believes your rants should think again.
Bearfoil where do you get your facts from, do you know anything about engines/EEC's, DEP's you posts are some of the worst I think I have ever read.'
I am saddened to read your post.
Perhaps if you followed this thread from the start you may have realised that there have been many genuinely knowledgeable and respected contributors who share a genuine concern for safety, and seek to identify the physics of the QF32 failure in order that 468 pax and flight crew might never be similarly endangered.
This forum is very unique in that it brings together those who fly the planes, and those who contribute to their construction and who advance the technology. This can only be good and potentially of enormous value, because no matter what our age - we can never cease to learn.
Of course in a public forum, there is bound to be a certain amount of 'noise'. But i think the pilots and engineers here are well able to filter that out? And in any event is there something bad about throwing thoughts around? I think it's called 'brainstorming'?
I think that perhaps I speak for all to say that you are welcome here if you believe you can contribute to the discussion and to an improved understanding in a positive way.
Personally, may I thank those who sit up front, and those who are engineers in whatever capacity on the ground for their constructive and well considered thoughts shared here.
Bearfoil, DERG, annex14 etc. some of the junk you are spouting as fact is unbelievably wrong. Anyone that believes your rants should think again.
Bearfoil where do you get your facts from, do you know anything about engines/EEC's, DEP's you posts are some of the worst I think I have ever read.'
I am saddened to read your post.
Perhaps if you followed this thread from the start you may have realised that there have been many genuinely knowledgeable and respected contributors who share a genuine concern for safety, and seek to identify the physics of the QF32 failure in order that 468 pax and flight crew might never be similarly endangered.
This forum is very unique in that it brings together those who fly the planes, and those who contribute to their construction and who advance the technology. This can only be good and potentially of enormous value, because no matter what our age - we can never cease to learn.
Of course in a public forum, there is bound to be a certain amount of 'noise'. But i think the pilots and engineers here are well able to filter that out? And in any event is there something bad about throwing thoughts around? I think it's called 'brainstorming'?
I think that perhaps I speak for all to say that you are welcome here if you believe you can contribute to the discussion and to an improved understanding in a positive way.
Personally, may I thank those who sit up front, and those who are engineers in whatever capacity on the ground for their constructive and well considered thoughts shared here.
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Thank you for your very thoughtful post. Indeed, there are some of us that are trying to understand what caused the engine failure on the Qantas Airbus A-380 in the interest of passenger safety. 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. It has nothing to do with how far we may be removed from current technology as some have suggested but the honesty in dealing with what has taken place and assurances that it is not going to happen again. The problem is not with the aircraft, in fact, it saved the day. The problem is with the lack of assurance from the engine manufacturer that the problem has really been completely solved going forward. As I see it, I have yet to see any believable assurances, especially with remarks such as this from the very top of the organization:
Now we know this not true, there have been at least two, one occurring on August 30, 2010, out of San Francisco, a Trent 700 engine, also on a Qantas aircraft.
Re-arranging the deck chairs on the fore-deck, while the band plays on in the main lounge to comfort the stockholders, is not what this is about.
There is enough credible information on both sides of the pond to suggest that this event was not only predictable to occur at some time, but also preventable. It is with this in mind that we explore what happened and attempt to assemble some thoughts, ideas and our experiences as to the sequence of events leading to the failure and postulating what may need to be done to keep a replay from occurring.
It is nice that some of us are willing to share in this forum, while others, perhaps with even more knowledge, are willing to play the "I know more than you do, but I am not saying" role.
Thanks again,
Sir John Rose spoke publicly for the first time about the problems with its Trent 900 engine used on the Airbus A380, parts of which exploded last November on a Qantas flight from Singapore to Sydney.
The company said that such uncontained engine failures occur roughly once a year in the global civil aviation sector. Rolls-Royce last suffered such an engine fault in 1994.
The company said that such uncontained engine failures occur roughly once a year in the global civil aviation sector. Rolls-Royce last suffered such an engine fault in 1994.
Re-arranging the deck chairs on the fore-deck, while the band plays on in the main lounge to comfort the stockholders, is not what this is about.
There is enough credible information on both sides of the pond to suggest that this event was not only predictable to occur at some time, but also preventable. It is with this in mind that we explore what happened and attempt to assemble some thoughts, ideas and our experiences as to the sequence of events leading to the failure and postulating what may need to be done to keep a replay from occurring.
It is nice that some of us are willing to share in this forum, while others, perhaps with even more knowledge, are willing to play the "I know more than you do, but I am not saying" role.
Thanks again,
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... there have been at least two, one occurring on August 30, 2010, out of San Francisco, a Trent 700 engine, also on a Qantas aircraft.
The other related case was a T1000 on test bench, early Aug. 2010 IIRC.
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u416967 writes:
It is obvious that a lot of the newer "technologies" are little understood, particularly with regards oil temperature, oil systems and controls.
It is obvious that a lot of the newer "technologies" are little understood, particularly with regards oil temperature, oil systems and controls.
Let me qualify myself. I don't work in the aviation industry, I'm not a pilot.
Now, to take you to task for some of your earlier and rasher statements regarding the quality of this thread and those who drive it.
This thread has been both fascinating and an education for me as I have followed the discussion; the many contributory posters (bear, turbine, loma, et al) have brought forth valid information as well as insight.
Frankly, to walk into this discussion and call most of it rubbish or garbage does not add anything to its value, and if that is the best contribution you can make, I would suggest that you hold it for a cocktail lounge somewhere and argue over designer cocktails with those who haven't put a lot of effort into trying to discern exactly what caused an engine, one of the most-touted engines, of a 5-star engine builder to self-destruct on the wing of a Qantas flagship aircraft.
Before you decide to reply with some snarky comment to this post, I suggest you re-read this thread and all the links found herein. You might at that point decide that you were in fact completely wrong in classing most of this discussion as refuse.
Cheers!
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writes:
Rottenray, you have just stated that you have learnt most of what you know from this thread.
Rottenray, you have just stated that you have learnt most of what you know from this thread.
(for those who wish to fact-check, and for u415967 to review, this is the post...)
all that counts are the authorities and they will have all of the information around them
And the authorities never, ever have to enlist the help of outside talent - like engineers, experienced line mechanics, et cetera.
I will refrain from entering into any more discussions on this subject.
Carry on, guys - and thanks for the discussion so far!
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Junk
"Bearfoil, DERG, annex14 etc. some of the junk you are spouting as fact is unbelievably wrong. Anyone that believes your rants should think again."
The most unbelievable fact is how the RR management took the junk as presented by Oxford University and used it in a way that resulted in endangering the public. When the public buys a ticket to ride on these aircraft they do not believe they are entering a lottery.
The BBC interviewed an aerospace analyst last week who stated that "RR know they have a problem". Then we have the article in the THE ECONOMIST, a weekly once noted for its objectivity, that reads more like some thing from THE INVESTORS CHRONICLE.
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. Those of you who cannot make a judgement yet should reread this whole thread.
RR are taking a hell of gamble with people who place their trust in the T900s with their lives, not money as in the stock market, with life and limb. You think this is hyperbole...?
The most unbelievable fact is how the RR management took the junk as presented by Oxford University and used it in a way that resulted in endangering the public. When the public buys a ticket to ride on these aircraft they do not believe they are entering a lottery.
The BBC interviewed an aerospace analyst last week who stated that "RR know they have a problem". Then we have the article in the THE ECONOMIST, a weekly once noted for its objectivity, that reads more like some thing from THE INVESTORS CHRONICLE.
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. Those of you who cannot make a judgement yet should reread this whole thread.
RR are taking a hell of gamble with people who place their trust in the T900s with their lives, not money as in the stock market, with life and limb. You think this is hyperbole...?
Last edited by DERG; 14th Feb 2011 at 05:55.
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Suzeman- Just been advised that A380 VH-OQD on QF32 LHR - SIN has diverted into DXB. Not the same a/c as that involved at SIN, but obviously some problem that made the crew decide on this precautionary diversion.
A Qantas plane flying from London to Singapore was diverted out of Iraqi airspace on Monday, the Australian flag carrier said, after officials on the ground refused to recognise a pre-approved flight plan.
QF 32 had to divert to Dubai to refuel as a result, a Qantas spokesmodel told AFP, describing it as an "unusual" incident.
"The flight path was interrupted by Iraq Air Services who would not allow the aircraft into Iraq airspace due to them not recognising the authority (to enter) and the pre-approved flight path request," the spokesmodel said.
Qantas was now liaising with Iraqi authorities to determine why the plane had been denied entry
QF 32 had to divert to Dubai to refuel as a result, a Qantas spokesmodel told AFP, describing it as an "unusual" incident.
"The flight path was interrupted by Iraq Air Services who would not allow the aircraft into Iraq airspace due to them not recognising the authority (to enter) and the pre-approved flight path request," the spokesmodel said.
Qantas was now liaising with Iraqi authorities to determine why the plane had been denied entry
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Very good news Trent!
Barit
The stuff that the military do and the stuff the civil avaition does are connected intrinsically but are incomparable in terms of day to day routines. Is that not obvious Barit?
The problem arises when the UK Ministry of Defence people find themselves at the whim of Adam Smith. They suddenly realise that they have a bunch very greedy people to please, many with the morals of a rattle snake.
Indeed the public they once "served" are now seen as pawns in a game.
Of course Airbus, RR and almost all the big aircraft manufacturers have some income from military projects. These people are given only parts of the picture for reasons of security.
What they do not realise is that civil aviation has no "state secrets". In this sense firms like QuintiQ are immature and still unconnected with civil responsibility. viz. LITIGATION
Moreover we have evidence that the academics they employ readily provide them with ammunition to make probalistic projections about mechanical devices they really know SFA about.
Not military hardware, a civil airliner with over 450 people on board flying over populated communities.
OPEN TO FORUM
Some of you maybe asking IF the manufacturers know everything about the aircraft they sell.
This link is interesting:
AvioConsult - Aircraft Expert and Consultant - Home Page
This will take a couple of hours to fully digest but is well worth reading.
Barit
The stuff that the military do and the stuff the civil avaition does are connected intrinsically but are incomparable in terms of day to day routines. Is that not obvious Barit?
The problem arises when the UK Ministry of Defence people find themselves at the whim of Adam Smith. They suddenly realise that they have a bunch very greedy people to please, many with the morals of a rattle snake.
Indeed the public they once "served" are now seen as pawns in a game.
Of course Airbus, RR and almost all the big aircraft manufacturers have some income from military projects. These people are given only parts of the picture for reasons of security.
What they do not realise is that civil aviation has no "state secrets". In this sense firms like QuintiQ are immature and still unconnected with civil responsibility. viz. LITIGATION
Moreover we have evidence that the academics they employ readily provide them with ammunition to make probalistic projections about mechanical devices they really know SFA about.
Not military hardware, a civil airliner with over 450 people on board flying over populated communities.
OPEN TO FORUM
Some of you maybe asking IF the manufacturers know everything about the aircraft they sell.
This link is interesting:
AvioConsult - Aircraft Expert and Consultant - Home Page
This will take a couple of hours to fully digest but is well worth reading.
Last edited by DERG; 14th Feb 2011 at 09:17. Reason: additional
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CF6-45/50 Uncontained Failures
Good information on other uncontained failures. They can occur more frequently on engines that are nearly 40 years old and for one reason or another, are not well maintained. Now, I don't want you to think that I am making this up or a "sciolist" as you like to put it. So here are the facts, read on:
AD Aimed At Delinquent CF6 Operators | AVIATION WEEK
By the way, the CF6-45 engine was designed for the Boeing 747-100SR (short range), especially for ANA and their short routes inside Japan. Just thought you would like to know.
AD Aimed At Delinquent CF6 Operators | AVIATION WEEK
By the way, the CF6-45 engine was designed for the Boeing 747-100SR (short range), especially for ANA and their short routes inside Japan. Just thought you would like to know.
Last edited by Jetdriver; 14th Feb 2011 at 14:03.
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I wasn't counting the Trent 1000. The second one I was referring to was this one: http://www.ntsb.gov/ntsb/GenPDF.asp?...04IA002&rpt=fa
FAA Airworthiness Directive
During 2004, an incident was reported involving uncontained multiple intermediate-pressure (IP) turbine blade release on a Trent 700 engine. The blade release was the result of an overspeed of the IP turbine rotor that was initiated by an internal fire in the high-pressure/intermediate-pressure (HP/IP) bearing chamber. Post-incident analysis and investigation has established that blockage of the HP/IP turbine bearing oil vent tube due to carbon deposits was a significant factor in the failure sequence. The Trent 800 has a similar type design standard to that of the Trent 700 and has also been found in service to be susceptible to carbon deposits in the oil vent tube.
FAA Airworthiness Directive
During 2004, an incident was reported involving uncontained multiple intermediate-pressure (IP) turbine blade release on a Trent 700 engine. The blade release was the result of an overspeed of the IP turbine rotor that was initiated by an internal fire in the high-pressure/intermediate-pressure (HP/IP) bearing chamber. Post-incident analysis and investigation has established that blockage of the HP/IP turbine bearing oil vent tube due to carbon deposits was a significant factor in the failure sequence. The Trent 800 has a similar type design standard to that of the Trent 700 and has also been found in service to be susceptible to carbon deposits in the oil vent tube.
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Rolls Royce and The Economist.
Readers will note that THE ECONOMIST ran a very subjective and somewhat biased story about the future of RR.
Rolls-Royce: Per ardua | The Economist
It is no suprise to learn that a non executive CHAIRMAN of RR is: SIR SIMON ROBINSON
"Appointed to the Board in 2004 and appointed Non-executive Chairman in January 2005. He is the founder member of Simon Robertson Associates LLP and a non-executive director of HSBC Holdings plc, Berry Bros & Rudd Ltd, and The Economist Newspaper Limited.
He is a director of The Royal Opera House Covent Garden Limited and a Trustee of The Eden Project and the Royal Opera House Endowment Fund. He is the former President of Goldman Sachs Europe Limited, a former non-executive director of the London Stock Exchange, Invensys plc (formerly BTR plc), Inchcape and a former chairman of Dresdner Kleinwort Benson."
HSBC is one of two clearing banks for RR.
Futhermore HELEN ALEXANDER a non excutive director of RR also has connections with THE ECONOMIST:
"Appointed to the Board in September 2007. Helen Alexander was Chief Executive of The Economist Group from 1997 until July 2008, having joined the company in 1984. She has an MBA from INSEAD. She was Managing Director of The Economist Intelligence Unit from 1993 until the end of 1996"
Source:
Rolls-Royce Group plc
65 Buckingham Gate, London SW1E 6AT. Company number 4706930,
UK VAT number GB 345 8860 22.
Rolls-Royce: Per ardua | The Economist
It is no suprise to learn that a non executive CHAIRMAN of RR is: SIR SIMON ROBINSON
"Appointed to the Board in 2004 and appointed Non-executive Chairman in January 2005. He is the founder member of Simon Robertson Associates LLP and a non-executive director of HSBC Holdings plc, Berry Bros & Rudd Ltd, and The Economist Newspaper Limited.
He is a director of The Royal Opera House Covent Garden Limited and a Trustee of The Eden Project and the Royal Opera House Endowment Fund. He is the former President of Goldman Sachs Europe Limited, a former non-executive director of the London Stock Exchange, Invensys plc (formerly BTR plc), Inchcape and a former chairman of Dresdner Kleinwort Benson."
HSBC is one of two clearing banks for RR.
Futhermore HELEN ALEXANDER a non excutive director of RR also has connections with THE ECONOMIST:
"Appointed to the Board in September 2007. Helen Alexander was Chief Executive of The Economist Group from 1997 until July 2008, having joined the company in 1984. She has an MBA from INSEAD. She was Managing Director of The Economist Intelligence Unit from 1993 until the end of 1996"
Source:
Rolls-Royce Group plc
65 Buckingham Gate, London SW1E 6AT. Company number 4706930,
UK VAT number GB 345 8860 22.
Last edited by DERG; 14th Feb 2011 at 18:23.
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what do you want to say, really?
U415967:
looks like you may have not spent too much time reading all this forum before starting to write
And possibly that is why RR is currently at 3rd iteration (C) of the solution for fixing the T9 - right? So who was accepting the previous iterations? RR by itself or the authorities? I understand thay you are aware that the authorities would not exist if not the big companies who do operate on this market. Just read what Derg has posted a moment ago about 'unbiased' opinion by the economist..
in your reading you must have somehow omitted some of the French reports where raison d'etat was definitely more important than other facts - see Habsheim and recent Concorde crash...
If you really know more than prove it or quit writing unsubstantiated opinions.
I am sorry but we are trying to stick to discussing the problems with Trent 900 and not healing some sore personal egos
History has proven that those who really know either keep doing or keep quiet
Welome to PPRuNe
looks like you may have not spent too much time reading all this forum before starting to write
I am not here to cause arguments or to give you my opinion on the matter, as it doesn't count, all that counts are the authorities and they will have all of the information around them. The fact that the A380 with Trent 900 engines are flying shows that all of the authorities are happy with the explanation given for the unfortunate accident that occurred on the QANTAS A380.
I know that you are all intelligent people, so I suggest that you start to believe what is in the ATSB reports and any other accident report there is, as usually they aren't incorrect.
- see Habsheim and recent Concorde crash...
I am sorry if people don't value my opinion, however I know for a fact that most of the speculation on here is incorrect in some way. I will not be giving more details but suffice to say, I do know what I am talking about on this and am close to it unlike most other posts on here, especially those by the vociferous few.
I am sorry but we are trying to stick to discussing the problems with Trent 900 and not healing some sore personal egos
History has proven that those who really know either keep doing or keep quiet
Welome to PPRuNe
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Derg:
exposing such information to public poses a threat to national security
Now you can understand why some countries do close internet access at all - remember what some BIG money makers say - big money like it quiet.
thanks for this info
exposing such information to public poses a threat to national security
Now you can understand why some countries do close internet access at all - remember what some BIG money makers say - big money like it quiet.
thanks for this info
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DERG
Nice background information, one could have expected such a vitae.
However, allow me to remember you to the saying that "caution is the safer part of bravery".Or with other words, I fear that you are opening another "broadside".
So better lets exchange these kind of info in pmīs or mails ??
And as barit1 has stated in another context - always check your six
However, allow me to remember you to the saying that "caution is the safer part of bravery".Or with other words, I fear that you are opening another "broadside".
So better lets exchange these kind of info in pmīs or mails ??
And as barit1 has stated in another context - always check your six
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Hahah they will send the UK FSB after me?
Thanks for your concerns. I was born on the west side of the iron curtain and I uphold the values of freedom. The day we become scared is the day we have lost that freedom. 165 million people died in war last century and another 469 people almost died as a consequence of this nonsense with the RR engine. Nah...these folks do not scare me.
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Sorry for the delay, here is a summary of EEC controls re: shutdown in flight. (T9).
The engine protection system is incorporated into the EEC. Its hardware performs the following functions:
LP and IP Rotor Overspeed protection.
LP Turbine Overspeed protection.
Thrust control malfunction protection.
EEC monitors LP and IP compressor shaft speeds (N1, N2). this is done via a Phonic wheel on the shaft of each, forward of the Ball bearings. If speeds of these shafts are above an indexed value, the engine is shutdown. The LP Compressor shaft is also compared constantly with LP Turbine module, and if discrepant, the engine is assumed to have had a shaft loss, and the powerplant is shutdown.
Thrust Control Malfunction (TCM)
EEC monitors engine thrust, both Turbofan Power ratio, (TPR), and N1 Speed. If either exceeds commanded values by an indexed limit, TCM prot operates by reducing Power, or it will shut the engine down, depending on Airspeed and altitude. Flight Controls Primary Computer (Prim), provides a discrete signal hardwired to the EEC active channel, which then allows engine shutdown.
Each channel of the EEC has a hardware protection which is separate from all other EEC functions. Comparators determine if an overspeed or TCM have passed threshold; if a fuel cutoff or reduction is set, Programmable Array Logic (PAL) functions alert the opposite channel, and if both channels agree, a signal is sent to the protection motor in the HydroMechanical Unit (HMU).
If in degraded operation, (power supply or processor failure), shutdown can be commanded by one PAL.
One other thing. The LP and IP shaft speed is sensed by Phonic wheels, the HP shaft speed is derived from the actual RPM sensed at the Alternator, off the Gearbox drive. 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.
Seems relatively Human exclusive to me.
The engine protection system is incorporated into the EEC. Its hardware performs the following functions:
LP and IP Rotor Overspeed protection.
LP Turbine Overspeed protection.
Thrust control malfunction protection.
EEC monitors LP and IP compressor shaft speeds (N1, N2). this is done via a Phonic wheel on the shaft of each, forward of the Ball bearings. If speeds of these shafts are above an indexed value, the engine is shutdown. The LP Compressor shaft is also compared constantly with LP Turbine module, and if discrepant, the engine is assumed to have had a shaft loss, and the powerplant is shutdown.
Thrust Control Malfunction (TCM)
EEC monitors engine thrust, both Turbofan Power ratio, (TPR), and N1 Speed. If either exceeds commanded values by an indexed limit, TCM prot operates by reducing Power, or it will shut the engine down, depending on Airspeed and altitude. Flight Controls Primary Computer (Prim), provides a discrete signal hardwired to the EEC active channel, which then allows engine shutdown.
Each channel of the EEC has a hardware protection which is separate from all other EEC functions. Comparators determine if an overspeed or TCM have passed threshold; if a fuel cutoff or reduction is set, Programmable Array Logic (PAL) functions alert the opposite channel, and if both channels agree, a signal is sent to the protection motor in the HydroMechanical Unit (HMU).
If in degraded operation, (power supply or processor failure), shutdown can be commanded by one PAL.
One other thing. The LP and IP shaft speed is sensed by Phonic wheels, the HP shaft speed is derived from the actual RPM sensed at the Alternator, off the Gearbox drive. 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.
Seems relatively Human exclusive to me.