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autothrust
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 11:18 am

Quoting XT6Wagon (Reply 94):
And you are full on nonsense, As far as I know, no airliner has EVER had a "open window" style failure at altitude.

Way offtopic, but thats wrong. British Airways Flight 5390 (BAC-111),the airplane suffered an explosive decompression when an improperly installed pane of the windshield blew out at 17,300 feet. The Captain was almost blown out of the plane.

http://en.wikipedia.org/wiki/British_Airways_Flight_5390
 
Viscount724
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 11:29 am

Quoting 777law (Reply 105):
fly around 100,000+ miles a year too and I totally agree. . . I'll take a 777 over an A330 / A340 any day of the week -- in fact, I purposely avoid airlines that fly 330's / 340's on the routes I fly. . . for me the 777 is more comfortable, quieter and an all around better product than the 330's / 340's. . . Like my signature says, "If it's not a Boeing, I ain't going!"

While I like the 777, I disagree that it's quieter than the A330/340, especially compared to the A340 which in my opinion is the quietest widebody. I find engine noise more noticeable on 777s especially when sitting near the engines. I recall one AF 772 flight CDG-IAD a couple of years ago where I was right next to the right engine and there was a noticeable minor vibration through the seat that seemed to be engine-related, almost like the engines weren't quite synchronized.

A330/340 also gives you just a 1 in 4 chance of a middle seat in Y class, not as good as the 767's 1 in 7 but better than the 777's 1 in 3 (1 in 2.5 on the few 777 operators with 10-abreast in Y on 777s, e.g. Emirates). And there's generally NO risk of a middle seat in business class on the A330/340 with the usual 2-2-2 layout, while many 777's are 2-3-2.

One factor in favour of the 777 (and 747) is it's slighly higher cruising speed than A330/340 (and B767). But that rarely means more than 10 or 15 minutes on typical US/Canada east coast-Europe sectors.

[Edited 2007-03-06 03:35:00]
 
XT6Wagon
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 11:30 am

Quoting Antskip (Reply 106):

I suppose the happy feeling that results from one knowing that statistically, once the twin is a single, the chances of failure of the last engine are twice as unlikely as the previous engine failure, might be encouraging (!). On the other hand, if it were to happen, that is the beginning of the end-game also. Using the same logic, a quad has three steps to the end-game, each statistically much less likely to happen: from a quad to a tri to a twin and finally to a single (though how able a quad on a single? -nowhere near the ability of a twin on a single, itself far inferior to a single on a single), then nothing. But the quad has two more levels of redundancy before it reaches the point of having the statistical advantage of a twin and, finally, a single.

But thats wrong. Your chance to see total engine failure on a twin engine after one fails is the same as your chance to see complete engine failure in a 4 engine once one of its engine fails. Its simply because multiple engine failures are almost always due to nothing in the engine itself. Its fuel, bad MX, volcanic ash, whatever. ETOPS is in many ways safer given the extra attention to engine MX, and the requirement that the engines on each wing are kept separate so you don't manage to have the same idiot install something wrong in both. But on your A340 you can have Mr HamfistMcIdiot install the same seal/fuel pump/oil fitting/whatever wrong on all 4 engines, thus causing all 4 to puke out mid-flight with no fault to the engine maker....
 
Pihero
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 9:40 pm

Quoting ConcordeBoy (Reply 91):
...the exact same thing that would've happened had it been a 3 or 4-engined aircraft suffering from a total flameout.

That's not the point. Read again.

Quoting XT6Wagon (Reply 94):
Please read how ETOPS works. I assume a quick 5min web search would get you plenty of non-biased sources.

The difference beteween you and I is that this is not a game to me. A second difference is that I trained for it and ETOPS also need to adhere to the "normal" regs, be them over performance or fuel planning or both at the same time.
Five minutes to get to grips with all the regs pertaining to fuel planning on ETOPS... I hope your pilots have done more than that.

Quoting Lemurs (Reply 95):
Your ETOPS arguments in this thread have revolved around the fact that you don't trust statisticians and statistics because you have a bad feeling about things

No, not really. I've seen too many occurences of a failure "that had a chance in 10 tothepowerofzillions " to happen...Some hapless pilot manages - not always - to come back...and there's hardly an excuse from those clever statisticians...

Quoting Pygmalion (Reply 101):
Any pilot that says he doesn't trust statistics should be raising goats not flying.

Funny you say that : I raise sheep and I'm a scout commissioner !

Quoting Antskip (Reply 106):
I agree on "gut feelings" (though sometimes they can indicate something is not quite complete about the data one has available, so it urges one to open one's eyes further, re-look / seek further data). It is also a vague term which can mean everything from what is seems to mean, to uses of the rational intellect and imagination, which are a long way from the gut, and are the basis of all knowledge (and discussion). If "feeling' is the idea of blind passionate lack of knowledge, then I completely agree. There is no help there - it is a human physical response, not an act of vision (open-eyed clear reason).

May I give an example ?
Happened years ago...was flying a 737 over the arabian Gulf and lost an engine generator...
the check-liost called for transfers and an APU start to re-establish a normal distibution...Done...
Then, gut feeling hit : what if ?.. I could only lose a gen through an electrical fault inside... or I've lost the mrchanical link between the gen and the engine, i.e the gear box...if I don't disconnect the gen, I might end up with a nasty wheels-and-cogs salad down there...
HIT the GEN DISC !
Later, back to base, my gut feeling had been proven right. Could have lost a lot through fire...
But some clever ass will tell me that I had RWO fire extinguishers...Right ?
Antskip, thanks for some very thoughtful posts.
 
ConcordeBoy
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 10:09 pm

Quoting Pihero (Reply 110):
That's not the point. Read again.

I did, you have no (valid) point. Deal.
 
Pihero
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 10:27 pm

Quoting ConcordeBoy (Reply 111):
I did, you have no (valid) point. Deal.

This is what I wrote :

Quoting Pihero (Reply 87):
Did statisticians cover the human element involved in the AT 330 which lost all its fuel ? What would have happened had the plane kept its original - and much further north - track ?
And with an airplane lost in ETOPS conditions without any way of knowing what happened (there is an oceanic trench in that area ), would ETOPS still be as it is now ?

my point is that we'd have lost the airplane, with very remote chance of recovering it or at least the recorders.What would have been the result ? An EWTOPS airplane lost to unknown causes over the pond... I do not think ETOPS certs would have stayed the same.
Clear enough for you, now ?
 
PolymerPlane
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 11:13 pm

Quoting Pihero (Reply 110):
The difference beteween you and I is that this is not a game to me. A second difference is that I trained for it and ETOPS also need to adhere to the "normal" regs, be them over performance or fuel planning or both at the same time.
Five minutes to get to grips with all the regs pertaining to fuel planning on ETOPS... I hope your pilots have done more than that.

Jeez, there's no need to be such a jerk. Not everybody works in airline business. You don't need training to understand and read about ETOPS regulation... From FAA website:

the original 60 minutes rule (121.161), and I quote:

Quote:
(a) Unless authorized by the Administrator, based on the character of the terrain, the kind of operation, or the performance of the airplane to be used, no certificate holder may operate two-engine or three-engine airplanes (except a three-engine turbine powered airplane) over a route that contains a point farther than 1 hour flying time (in still air at normal cruising speed with one engine inoperative) from an adequate airport.

from the ETOPS advisory circular that governs ETOPS 180 min, (AC 124-42A)

Quote:
for the purpose of this AC, extended range operations are those flights conducted over a route that contain a point further than one hour flying time at the approved one-engine inoperative cruise speed (under standard conditions in still air) from an adequate airport

http://www.airweb.faa.gov/Regulatory...9ba00751c8c/$FILE/Pages%201-15.pdf

Quoting Pihero (Reply 112):

my point is that we'd have lost the airplane, with very remote chance of recovering it or at least the recorders.What would have been the result ? An EWTOPS airplane lost to unknown causes over the pond... I do not think ETOPS certs would have stayed the same.

It has not happened, so I can't speculate about it. But, according to your logic, if a 4 engine plane is lost in the middle of nowhere and you don't know what happened, all aircraft's regulation will be changed? maybe include 4 engine planes into "ETOPS" regulations?

Cheers,
PP
 
Pihero
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 11:30 pm

Quoting PolymerPlane (Reply 113):
Not everybody works in airline business. You don't need training to understand and read about ETOPS regulation...

You have just touched about 1/1000000000000000000000 of the subject.
Proof ? give me the basics -just the basics - of the flight planning of an ETOPS flight, say between LHR and EZE and another between LHR and HKG. What will you consider ? Where will your alternate be ? what will your options be in terms of systems failure ?
Unless you can answer that, your totally out of your depths here .
And by the way,what are you an engineer of ?
And ,yes, I'm a jerk because I know what I'm talking about. Unlike a few on this forum.
 
widebodyphotog
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RE: 777 Vs. A340 - AC CEO Comments

Tue Mar 06, 2007 11:43 pm

Quoting Antskip (Reply 106):
The above is the sort of use of "hard facts" / statistics or whatever that is a problem. To argue that statistics shows (and so does logic) that having half as many engines halves the likelihood of engine failure is fraught with problems. The logic also means that a single is twice as unlikely to have engine failure as a twin. But the implication that having statistically half the chance of engine failure somehow makes a twin more than a match for a quad, in the safety stakes over areas far from land, is problematic. Though a single may be 4X as unlikely to have engine failure as a quad; if that were to happen, it is the end game for the single (now zero) there and then. Similarly, though a twin is statistically only half as likely to lose an engine as a quad, it then finds itself in the position of a single - with no redundancy left

What's problematic is that people are saying that there is a problem with ETOPS when there really is none. I mean you supported your assertion with the "straw man" argument of a single engine airplane having no redundancy after an IF. ETOPS regulations are about much more than engines. Well, there are no single engine airliners and none proposed... Redundancy is built in by ETOPS design meaning your have to design the plane to a potential ETOPS certification. This includes fire supression, electrical, and hydraulic systems in addition to propulsion. In the event of a single IFSD the ETOPS twin maintains redundancy of ancillary systems...

What is also problematic is ignoring that the practical application of ETOPS has resulted in no loss of life or aircraft to date. There are a great many things that bring planes down and ETOPS has never appeared on that list. That is not to say it never will, but by design and in practice you are more likely to takeoff and land at your planned destination flying in an ETOPS mission on an ETOPS certified twin than any other arliner. If ETOPS standards were not as high as they are then we'd see many many more engine failures, diversions, and most likely crashes. ETOPS certification is not an easy thing to do, you have to qualify and maintain the qualification for it. If you don't you lose it simple as that.

So what's the point of all this harrang about ETOPS safety? Would those opposed come out and say they wish to ban ETOPS operations and mandate that manufactures build airplanes with three or more engines? And why three our four why not six or eight engines for the ultimate in safety, comfort and piece of mind for all who fly...



widebodyphotog
 
Lemurs
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 12:11 am

Quoting Pihero (Reply 114):
And ,yes, I'm a jerk because I know what I'm talking about. Unlike a few on this forum.

You have yet to demonstrate that. You keep coming back to the same tired argument...you know better because your feelings and experiences say so. The fact that you are here talking to us demonstrates that you have managed to survive all these bad statistics...and the fact that no one to date has ever died on an ETOPS flight because of a dual-engine failure, suggest you're full of baloney still.

Self-righteous, but still baloney.
 
ConcordeBoy
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 12:41 am

Quoting Pihero (Reply 112):
I do not think

...no kidding.

Quoting Pihero (Reply 112):
Clear enough for you, now ?

That you have no valid point? Yeah, I said that the first time.

Say your scenario did take place with that flight..............
Aircraft goes down for initially-undetermined causes; justification to adjust ETOPS procedures per se, even temporarily? No. Historical precedent: MS990.

Aircraft later determined to have gone down due to a cause that would've crippled every aircraft in its situation regardless of engine count; justification to adjust ETOPS procedures? No.

[Edited 2007-03-06 16:46:50]
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 12:58 am

Quoting Antskip (Reply 106):
To argue that statistics shows (and so does logic) that having half as many engines halves the likelihood of engine failure is fraught with problems.

I don't believe that anyone has seriously argued that there is no risk in flying twins over large oceans; but the fact remains that we have been doing it long enough now to relegate the risk as being on the same order as being struck in flight by a meteorite. There has never been a jet transport that has suffered two unrelated engine failures on the same flight, and that includes all the quads flying before ETOPS was invented. That is why ETOPS was considered practical to begin with.

[Edited 2007-03-06 17:05:21]
 
Pihero
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 1:45 am

Quoting SEPilot (Reply 118):
There has never been a jet transport that has suffered two unrelated engine failures on the same flight, and that includes all the quads flying before ETOPS was invented

Not true. remember the plane between Porto Rico and Miami which lost all engines to oil starvation ? They were only saved by the crew insisting that grilling one engine was the better situation to a ditching.
Not to mention a well known 747 in volcanic ash. fortunately, they weren't in max ETOPS situations.

Quoting ConcordeBoy (Reply 117):
Aircraft later determined to have gone down due to a cause that would've crippled every aircraft in its situation regardless of engine count; justification to adjust ETOPS procedures? No.

You wouldn't have known what brought it down. And , yes, I believe that ETOPS rules would have been reviewed, at least for the public's benefit.

Quoting Lemurs (Reply 116):
no one to date has ever died on an ETOPS flight because of a dual-engine failure,

You really are full of yourself, and without a lot of justification, aren't you ?
For you - as for a lot of people lurking on this forum - ETOPS is just about being able to fly a given distance to a possible alternate in case of an engine failure.
Yeah ! You haven't considered all the implications of that engine loss, in terms of performance, terrain considerations...and so on...
Although I gave you the opportunity to learn further, you just came out with an extract of the FARs that only cover a one-engine diversion...and I told you that you need a lot more to study.
Face it, You haven't got the first clue on what you're talking about.
I grant you something, though : It won't be a dual engine failure that will be the original cause of a hull loss on ETOPS, that one is covered pretty well...
 
ConcordeBoy
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 2:04 am

Quoting Pihero (Reply 119):
Not to mention a well known 747 in volcanic ash.

Um, exactly what was unrelated (as specifically stated in the earlier post) or independent about that aircraft's powerplant flame-outs?

Quoting Pihero (Reply 119):
I believe that ETOPS rules would have been reviewed,

...the first two words indicate that statements' utter inconsequence to operational precedent/reality.
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 2:14 am

Quoting Pihero (Reply 119):
remember the plane between Porto Rico and Miami which lost all engines to oil starvation

I do not know of this, but it still does not apply. I said UNRELATED engine failures. Fuel starvation, oil starvation (assuming a common supply-also, was this a jet transport?) or flying through an ash cloud are related, and would happen with 2 or 200 engines. I would be interested in the details of this event, though. When was it, and what airline and type of plane?
 
Lemurs
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 2:23 am

Quoting Pihero (Reply 119):
Not true. remember the plane between Porto Rico and Miami which lost all engines to oil starvation ? They were only saved by the crew insisting that grilling one engine was the better situation to a ditching.
Not to mention a well known 747 in volcanic ash. fortunately, they weren't in max ETOPS situations.

What does a volcano have to do with ETOPS? A 4-holer losing all of it's engines because of a volcano outside of ETOPS routing is MORE screwed than a 2-holer. You're not gliding 5 hours back to anywhere except the ocean. I'd be interested in seeing the other incident you're talking about, because I have seen nothing of the sort. I don't think I'd be going out on a limb to say that any incident of the type you're talking about involving engine maint would be far less likely to occur under ETOPS regime because the same mechnic wouldn't be doing work on both engines, so he couldn't screw them both up.

You're talking big, but you're not demonstrating in what fashion ETOPS is unsafe or failing to account for flight factors.
 
PolymerPlane
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 2:38 am

Quoting Pihero (Reply 114):

And ,yes, I'm a jerk because I know what I'm talking about. Unlike a few on this forum.

Beautiful logic... I hope I don't have to meet a lot of people with this logic.

Quoting Pihero (Reply 114):
Proof ? give me the basics -just the basics - of the flight planning of an ETOPS flight, say between LHR and EZE and another between LHR and HKG. What will you consider ? Where will your alternate be ? what will your options be in terms of systems failure ?

So what? you just punch in your little computer and come up with the route and alternate? so much for being an expert...

You can't even build your own argument. Your argument is basically: if you don't know everything in flight planning, don't even talk to me. Why do you even contribute to a forum with 99.9% of the contributors do not have flight planning knowledge.

All your examples above about failure of an ETOPS flight were not related to the ETOPS performance itself, but to all airliners, be it twin, tri or quad jets.

Everybody should remember this: ETOPS flight is not intended to make the flight fail proof, but to bring the safety margin of a twin to at least as safe as a quad/trijet.

If a quad faces fuel starvation in the middle of nowhere, the most likely outcome is the same as a twin and vice versa.

Cheers,
PP
 
widebodyphotog
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 3:36 am

Gosh, the crisis mongers have really come out in force on this one. Here is something to think about though. Air transportation when you boil things down is inherently unsafe. I mean look at what we are doing. Rocketing through the sky at 550 mph at 35,000+ feet in a pressurized aluminum tube! This at a basic level is not safe. What has happened over the evolution of aviation is that hard lessons have been learned and technology has advanced in the direction of mitigating the risks involved in air transport. That is the best we can do as we can never eliminate risk of mechanical or human failure. You can implement redundancy ad infinitum at all levels of aircraft systems and it still would not significantly lower the relative risks that an aircraft takes on by simply leaving the ground. The safest thing to do is not to fly airplanes at all and then they would be perfectly safe inanimate objects. But that is not their purpose, their purpose is to fly and over time through those hard lessons and innovation we have achieved the level of safety we have to this day. Not perfect, but with a pursuit of achieving an ever diminishing risk level ETOPS has demonstrated its standards and application to be superior in many respects.

I find it shocking that people who are supposedly highly engaged in the air transport business would use non-sequiter and hyperbole in order to support an unsupportable premise. Quite astounding really. Volcanoes, broken windshields, running out of fuel...these occurrences effect aircraft equally regardless of the number of engines and could only be mitigated against by designing for those specific threats to safety which would again be without regard to the number f engines.

Honestly let's move on past this nonsense. The pertinent points of this thread have been completely lost. The substance of what AC's CEO is very relevant I think so let's get back to it.



-widebodyphotog
 
Pihero
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 4:00 am

Quoting PolymerPlane (Reply 124):
So what? you just punch in your little computer and come up with the route and alternate? so much for being an expert...

You too, then Mr Polymerplane ?
That sentence shows EXACTLY where this lot is in terms of knowledge of fuel planninmg procedures, let alone EWTOPS particulars.
No, even very big computers cannot begin to cover what we need to plan a route.

Quoting PolymerPlane (Reply 124):
Why do you even contribute to a forum with 99.9% of the contributors do not have flight planning knowledge.

I tried to have a civilised discussion, and ended up very soon on the receiving end of T7 lovers' flak (I put all twins in the same basket) and to be honest,nobody gives a damn. I gave a few - read above - the idea to look further than "ETOPs bla bla blah... single engine speed ...distance to a diversion....", and NO ! they are all so full of the certainty that statistics will save them ! To me, that's an attitude not different from a magic culture ( cargo cult type) :" I believe because statistics and statisticians say so". Pathetic. No one except Antskip has raised the idea that having a one in a million hour chance of getting an engine failure could mean that You could see TWO failures happening at the same time after two million hours of safe use...and still stay coherent with stats.

Quoting Lemurs (Reply 123):
any incident of the type you're talking about involving engine maint would be far less likely to occur under ETOPS regime because the same mechnic wouldn't be doing work on both engines, so he couldn't screw them both up.

Who in the hell gave you that idea ?

Quoting PolymerPlane (Reply 124):
your examples above about failure of an ETOPS flight were not related to the ETOPS performance itself, but to all airliners, be it twin, tri or quad jets.

Oh ! At least someone has noticed that ! That is my main point : focusing on just the engine failure scenario blinds you to the fact that there are a lot of failures that could mess up your day as much, if not more than just the loss of an engine. Plus the fact that being single engine ops is just the beginning of another kettle of problem situations that you have not considered at all , once again because most people think of ETOPS as "over water". Factor some high terrain in your engine failure...getting interesting isn't it ?

Quoting ConcordeBoy (Reply 120):
Um, exactly what was unrelated (as specifically stated in the earlier post) or independent about that aircraft's powerplant flame-outs?

And now semantics... My opinion is that : two failures, related or not, on a twin mean only one thing : It's going down and to hell with your semantics !

Regards
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 4:21 am

Quoting Pihero (Reply 126):
My opinion is that : two failures, related or not, on a twin mean only one thing : It's going down and to hell with your semantics !

That is quite correct, but the historical evidence shows this is almost as likely to happen on a quad as a twin, since with the advent of jets there just have not been any multiple INDEPENDENT engine failures (with the possible exception of the Puerto Rico-Miami flight you mentioned above that I am still waiting for details on). This is not a matter of statistics, it is a matter of historical record. Based on that historical record I for one would not have any hesitation to board (or to fly if the opportunity were to present itself) any ETOPS-certified twin airliner for any destination on earth. As I have previously said the chances of both engines failing for independent reasons is considerably less than for something like running out of fuel, flying through an ash cloud, or any number of other potential catastrophic events that would render the number of engines irrelevant. You obviously do not feel that way; you are certainly entitled to your opinion. But I daresay you are in the minority both among pilots and the travelling public. For the record, I am a private pilot who flies single engine planes, so perhaps I have a more cavalier attitude towards potential engine failure than many.

[Edited 2007-03-06 20:40:12]
 
ACDC8
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 4:22 am

Quoting BoomBoom (Reply 89):
It did not make it. It ran low on fuel and had to divert to MAN anyway.

Yet MAN is still quite a fair way's for it to have run on 3 engines (it lost the engine at LAX I believe). If the aircraft involved were a twin, it would have had (I'm assuming) to return to the airport.

Quoting BoomBoom (Reply 89):
BA came in for a lot of criticism for that decision.

I'm sure they did, however, I don't believe the crew did anything against company policy or any safety regulations. The media and public critisize airlines for lot's of things.
 
ConcordeBoy
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 4:35 am

Quoting Pihero (Reply 126):
My opinion is that

...provenly worthless? Yes, we can see that.

Quoting Pihero (Reply 126):
two failures, related or not, on a twin mean only one thing

...indeed; it means the exact same thing as X failures, related or not, on any jet powered by X number of engines---- with multiple independent failure, on all aircraft twinjet or not, to be of such improbability vis-a-vis all other potential operational hazards as to be rendered statistically insignificant.

Your willing ignorance to this (incredibly simple) concept is what separates opinions by the likes of you from statistically prudent and time-tested allotments by .....wait on it...... every significant CAAC operating in modern society.
 
OldAeroGuy
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 4:43 am

Quoting Pihero (Reply 119):
Quoting SEPilot (Reply 118):
There has never been a jet transport that has suffered two unrelated engine failures on the same flight, and that includes all the quads flying before ETOPS was invented

Not true. remember the plane between Porto Rico and Miami which lost all engines to oil starvation ? They were only saved by the crew insisting that grilling one engine was the better situation to a ditching.
Not to mention a well known 747 in volcanic ash. fortunately, they weren't in max ETOPS situations.

Both of these events involved related failures.

The Eastern Airlines L-1011 oil starvation incident involved maintenance action. The same maintenance crew, working on all three engines, didn't install O-rings on the oil drain plugs when changing oil.

The BA 747 loss of all engines was of course related to encountering volcanic ash.

Interestingly, neither of these events involved a Twin.

Statistically, based on operational events, the most likely reasons to lose all thrust are fuel exhaustion and volcanic ash encounters. Both of these events are independent of number of engines.
 
PolymerPlane
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 4:46 am

Quoting Pihero (Reply 126):
You too, then Mr Polymerplane ?

I have never claimed that I am an expert.

Quoting Pihero (Reply 126):
Plus the fact that being single engine ops is just the beginning of another kettle of problem situations that you have not considered at all , once again because most people think of ETOPS as "over water". Factor some high terrain in your engine failure...getting interesting isn't it ?

So, are you saying we should all fly at least tri jet? even flying not under ETOPS rule, i.e. 60 min, you will still encounter these problems. Add into equation the lower quality standard of maintenance and parts on non ETOPS twin, you're screwed.

Just remember how dangerous it is flying a twin when you fly in a 737 or A320 or any other twin in that matter.

Quoting Pihero (Reply 126):
You could see TWO failures happening at the same time after two million hours of safe use...and still stay coherent with stats.

actually it's one in a trillion. heck, I'll take my chance in any plane at that probability.

Quoting Pihero (Reply 126):
Plus the fact that being single engine ops is just the beginning of another kettle of problem situations that you have not considered at all , once again because most people think of ETOPS as "over water". Factor some high terrain in your engine failure...getting interesting isn't it ?

So, are you saying that when considering ETOPS regulations and ops this factors aren't taken into account? If not, then I don't think you need that much expertise to plan a route.

Quoting Pihero (Reply 126):

And now semantics... My opinion is that : two failures, related or not, on a twin mean only one thing : It's going down and to hell with your semantics !

So, are you saying if a twin went into a volcano it won't restart, or there's 100% chance if another quad fly into a volcano it will restart?
are you also saying that if a quad have fuel or oil starvation it's not going down?

Basically just change whatever you've been saying about twin to quad or about quad to a twin and you'll still get the same result.

Quoting Pihero (Reply 126):
That is my main point : focusing on just the engine failure scenario blinds you to the fact that there are a lot of failures that could mess up your day as much

Yes, and a lot of other failures, without respect to however many engines you're flying on, can mess up your day.
Maybe we should list other incident/accidents that brings quad down, and discuss them just like you discuss about twin on ETOPS.

If you still think that your quad is much much much much safer than an ETOPS twin, that's fine. I don't really care, cause your opinion is not going to cause more engine failure on ETOPS flight. However, FAA and EASA feel differently, and I have put my ass on planes that depend on them too much to really worry about it.

Cheers,
PP

[Edited 2007-03-06 20:50:31]
 
BoomBoom
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:03 am

Quoting ACDC8 (Reply 128):
I'm sure they did, however, I don't believe the crew did anything against company policy or any safety regulations.The media and public critisize airlines for lot's of things.

It wasn't just the media and the public:

Quote:
Aviation officials in England and the United States are looking into the incident, and two retired jumbo-jet pilots now serving as air safety consultants said they were amazed at the decision to continue the flight.

''It's not impossible for him to make it, but he'd be a fool to try it,'' said Barry Schiff, a former TWA pilot. ''That decision just doesn't make any sense.''

Mel Heflinger, who used to fly 747s for United Airlines, said, ''I think he really stretched his luck to try to make the whole trip on three engines.''

''We are concerned,'' said Laura Brown, a spokeswoman for the Federal Aviation Administration. She said officials were determining whether any federal regulations were violated.

http://www.tribuneindia.com/2005/20050302/world.htm#5

The FAA proposed fining BA $25,000, far less than the cost the airline might have incurred by dumping 30,000 of fuel, and the $275,000 in compensation to passengers under European Union rules if the flight was more than five hours late.

Quote:
British Airways and the CAA both argued that the rules the carrier had to meet were Britain's, not those of the U.S. agency that was accusing the carrier of flying an "unairworthy" plane. "There's a slightly gray area," says Sir Roy McNulty, chairman of the CAA. "It's rare for an issue like this to come up. By and large, the FAA and we are perfectly aligned."

In the end, the nations avoided a fight over jurisdiction with a compromise. The U.S. acknowledged that international law gave Britain's CAA oversight of British Airways, and the CAA told the U.S. the airline had agreed to change its procedures for when an engine was out, at least while flying in U.S. air space.

http://online.wsj.com/article/SB115896261643871721.html
 
ACDC8
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:18 am

Quoting BoomBoom (Reply 132):
British Airways and the CAA both argued that the rules the carrier had to meet were Britain's, not those of the U.S. agency that was accusing the carrier of flying an "unairworthy" plane. "There's a slightly gray area," says Sir Roy McNulty, chairman of the CAA. "It's rare for an issue like this to come up. By and large, the FAA and we are perfectly aligned."

In the end, the nations avoided a fight over jurisdiction with a compromise. The U.S. acknowledged that international law gave Britain's CAA oversight of British Airways, and the CAA told the U.S. the airline had agreed to change its procedures for when an engine was out, at least while flying in U.S. air space.

Then they were not in any violations. Am I then correct with my original question (reply 84), quad's do have more options as oposed to twins when it comes to engine out scenarios?
 
robsawatsky
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:41 am

Quoting Pihero (Reply 126):
I tried to have a civilised discussion, and ended up very soon on the receiving end of T7 lovers' flak (I put all twins in the same basket) and to be honest,nobody gives a damn. I gave a few - read above - the idea to look further than "ETOPs bla bla blah... single engine speed ...distance to a diversion....", and NO ! they are all so full of the certainty that statistics will save them ! To me, that's an attitude not different from a magic culture ( cargo cult type) :" I believe because statistics and statisticians say so". Pathetic. No one except Antskip has raised the idea that having a one in a million hour chance of getting an engine failure could mean that You could see TWO failures happening at the same time after two million hours of safe use...and still stay coherent with stats.

Statistics are the only reliable means to predict potential future outcomes - it is most certainly not "magic culture". Probability and statistics is a field of science, not magic, religion or guesswork. It predicts outcomes based upon previous observations and previously proven mathametics. Anecdotal evidence and emotions are not the basis for determining safe operating and maintenance procedures. Your statement about "TWO failures" only demonstrates that you do not have the most basic understanding of probability and statistics.

The fact that we haven't seen a trail of devastation related to 2 vs 4 engine operations anywhere is validation of the methods used by the aviation industry and regulators to provide us with safe aircraft.
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:52 am

Quoting Robsawatsky (Reply 134):
The fact that we haven't seen a trail of devastation related to 2 vs 4 engine operations anywhere is validation of the methods used by the aviation industry and regulators to provide us with safe aircraft.

More than that, we haven't seen a SINGLE case of an accident in a twin that would not have happened had there been more engines.
 
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:52 am

Quoting ACDC8 (Reply 133):
Then they were not in any violations.

The were not in any violations of of BA company policy or CAA rules. However, the FAA wanted to fine them or operating an "unairworthy" plane.

Quoting ACDC8 (Reply 133):
Am I then correct with my original question (reply 84), quad's do have more options as oposed to twins when it comes to engine out scenarios?

Yes and no, because CAA told the U.S. the airline had agreed to change its procedures for when an engine was out, at least while flying in U.S. air space.

Quads have more options in an engine out scenario, but this doesn't overcome the disadvantages of quads. Twins are clearly superior, which is why the 777 outsells the A340 by such a large margin and Airbus is planning to replace the A340 with a twin A350.
 
jacobin777
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 6:42 am

Quoting Pihero (Reply 119):
Quoting SEPilot (Reply 118):
There has never been a jet transport that has suffered two unrelated engine failures on the same flight, and that includes all the quads flying before ETOPS was invented

Not true. remember the plane between Porto Rico and Miami which lost all engines to oil starvation ? They were only saved by the crew insisting that grilling one engine was the better situation to a ditching.
Not to mention a well known 747 in volcanic ash. fortunately, they weren't in max ETOPS situations.

Quoting ConcordeBoy (Reply 117):
Aircraft later determined to have gone down due to a cause that would've crippled every aircraft in its situation regardless of engine count; justification to adjust ETOPS procedures? No.

You wouldn't have known what brought it down. And , yes, I believe that ETOPS rules would have been reviewed, at least for the public's benefit.

Quoting Lemurs (Reply 116):
no one to date has ever died on an ETOPS flight because of a dual-engine failure,

You really are full of yourself, and without a lot of justification, aren't you ?
For you - as for a lot of people lurking on this forum - ETOPS is just about being able to fly a given distance to a possible alternate in case of an engine failure.
Yeah ! You haven't considered all the implications of that engine loss, in terms of performance, terrain considerations...and so on...
Although I gave you the opportunity to learn further, you just came out with an extract of the FARs that only cover a one-engine diversion...and I told you that you need a lot more to study.
Face it, You haven't got the first clue on what you're talking about.
I grant you something, though : It won't be a dual engine failure that will be the original cause of a hull loss on ETOPS, that one is covered pretty well...

you point out to two anomalies...one probably has a 50,000x greater chance of being killed in a vehicle accident, myocardial infarction/natural death, etc. than over the probability of losing a life in an aviation accident (don't know what the real numbers are) or in an "ETOPS-related" accident....its practically zero....

Quoting ACDC8 (Reply 128):

Yet MAN is still quite a fair way's for it to have run on 3 engines (it lost the engine at LAX I believe). If the aircraft involved were a twin, it would have had (I'm assuming) to return to the airport.

...if it were a twin, it had a less possible chance of "engine-out".... Wink

...even if it had to return, the benefits far outweigh the consequences....
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 6:48 am

Quoting Jacobin777 (Reply 137):
you point out to two anomalies...one probably has a 50,000x greater chance of being killed in a vehicle accident, myocardial infarction/natural death, etc. than over the probability of losing a life in an aviation accident (don't know what the real numbers are) or in an "ETOPS-related" accident....its practically zero....

The historical chance of being killed in an ETOPS accident is exactly zero.
 
jacobin777
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 6:54 am

Quoting SEPilot (Reply 138):
Quoting Jacobin777 (Reply 137):
you point out to two anomalies...one probably has a 50,000x greater chance of being killed in a vehicle accident, myocardial infarction/natural death, etc. than over the probability of losing a life in an aviation accident (don't know what the real numbers are) or in an "ETOPS-related" accident....its practically zero....

The historical chance of being killed in an ETOPS accident is exactly zero.

we're basically saying the same thing.... Wink
 
antskip
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 7:04 am

Thanks everyone for so many helpful comments! I learn so much in these threads, wherever they go. Like anyone, I learn most when I find that I am wrong. XT6Wagon in particular: you gave me a new perspective that I really appreciated - changed my whole way of looking at twins versus quads.

Quoting Robsawatsky (Reply 134):
Statistics are the only reliable means to predict potential future outcomes ...Probability and statistics is a field of science...It predicts outcomes based upon previous observations and previously proven tmathametics.

Statistics are a means of prediction based on the extension into the future through the understanding of regularities of past events, but they are not the only means of preventing accidents any more than they create opportunities - or design flying machines. Statistics as an empirical science (knowledge based on the expectation that past events will reoccur in the future in a predictable manner) - is an "after the event" science - a "a posteriori" science. But modern science, and modern technology, have been founded for centuries as well on a "before the event" science - "a priori" / Rational science - the comprehension of universal principles not dependent on empirical data, on past events, but a science of the possible. Statistical and empirical science is a handmaiden to rational science / knowledge.

The trouble about an attitude that just depends only on past / empirical events for learning is that many of the worst accidents happen "out of the blue", did not happen before...it is as if we all wait for the "unforeseeable" disaster to happen, so that a statistically viewable can emerge for us to learn from it. But that isn't the only way to avoid malfunction.
 
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 7:21 am

Quoting Antskip (Reply 140):
The trouble about an attitude that just depends only on past / empirical events for learning is that many of the worst accidents happen "out of the blue", did not happen before...it is as if we all wait for the "unforeseeable" disaster to happen, so that a statistically viewable can emerge for us to learn from it. But that isn't the only way to avoid malfunction.

It is true that statistical and probability analysis only looks at what has happened before, while many accidents happen for the first time, as you say "out of the blue", but the fact that it is now safer to fly halfway around the world (or farther) than it is to cross the street in front of your house is because we have done so much analysis of past accidents and tried to implement procedures to reduce the chances of the same type of accident happening again. The accident record proves that this approach has been successful. Of course, accidents will continue to happen, and there will be a first time for many of them. Who, for example, would have predicted that the fan disk on a DC-10 center engine would disintegrate and take out all the hydraulics with it? Obviously this was something that was not forseen. Likewise the Boeing designers never envisioned a situation where the 737 rudder could have an uncommanded hardover. But these events have not happened again (once the 737 problem was identified, at least.) The point of this is that the possibility of a twin engine airliner losing both engines is something that is obvious, and so extraordinary efforts have been taken to prevent that from happening, and so far have been successful. Obviously it still has a chance of happening, but it can safely be considered extremely remote precisely because we have been flying multi-engine jetliners for so long without it having happened even on two engines of a multi-engine plane.
 
Lemurs
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 7:32 am

Quoting Antskip (Reply 140):
The trouble about an attitude that just depends only on past / empirical events for learning is that many of the worst accidents happen "out of the blue", did not happen before...it is as if we all wait for the "unforeseeable" disaster to happen, so that a statistically viewable can emerge for us to learn from it. But that isn't the only way to avoid malfunction.

I think the disagreement at this point is around the semantics. Antskip, I don't think anyone here is saying that it can never happen. Everyone is saying that the regulations have turned it into an absurdly low probability. Of course, if we fly in twin jets for an infinite amount of time, odds dictate that something will have to happen, eventually. In the real world, infinite time will not exist, because turbine technology will likely be obsolete in another 50-100 years. So now, do the miniscule odds work in our favor in that limited timespan? 20 years of ETOPS says yes.

It's not impossible, but just because my odds of winning the Powerball are higher than dying in an ETOPS accident, doesn't mean I'm going to start playing PowerBall any time soon...  Wink
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 7:42 am

Quoting Lemurs (Reply 142):
It's not impossible, but just because my odds of winning the Powerball are higher than dying in an ETOPS accident, doesn't mean I'm going to start playing PowerBall any time soon...

But your chance of winning are zero if you don't play (or so my wife tells me.) Personally I agree with you.
 
DAYflyer
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 8:09 am

Quoting Viscount724 (Thread starter):
The 777s have a lower cost per available seat-mile than both of our four-engine A340 models – up to 26 per cent lower – and can fly further with a full payload. Two engines versus four mean better fuel efficiency and less maintenance expense.



Quoting Viscount724 (Thread starter):
The 270-seat 777-200LR will take over very long distance routes like Toronto-Hong Kong and do it at a 12 per cent lower seat-mile cost

I think when an airline customer says this about your products, it sums it up rather well, since they obviously did a complete cost analysis of the situation.
 
pygmalion
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 9:45 am

The thing I find the most interesting is Pihero is more than willing to impugn the use of statistics to show that twins are safe for EROPS but he is more than willing to fly an aircraft with a fly by wire sidestick that completely and entirely depends on statistics to show levels of safety and redundancy in exactly the same fashion as they are used in EROPS failure probability studies. You can't say it's not okay for one when you allow it for the other.

ETOPS or EROPS operations depend on much more than engine reliability studies as well, there are requirements for increased oxygen for pilots and pax, increased halon for cargo fire suppression, higher maintenance standards, increased system redundancy etc etc...

you are much safer on a EROPS certified twin than you are on a 4 holer.. the aircraft and systems are much more robust and have increased safety margins for all of those non-engine related systems above and beyond the demonstrated engine reliability standards.

So when you are 2.5 hours from an airport in a 4 holer with a cargo fire, you might wish you were on an aircraft that had enough halon to keep the fire damped down for 3 hours... an EROPS certified twin.
 
pygmalion
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 9:49 am

Folow up to the oil starvation problem discussed above.... a EROPS twin has larger oil tanks than a 4 engine aircraft. If a mechanic left the orings off a plug on all the engines.. I would rather be in a twin that had larger oil tanks than on a 4 engine aircraft that would be on fire before the twin ran out of oil.
 
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zeke
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 9:56 am

Quoting Accargo (Reply 67):
Let me guess, you are flying the 340?

The policy applies to 340/747

Quoting BoomBoom (Reply 70):

How convenient for you to hide behind company policy when you don't want to answer a question, because to do so would undermine your silly implication that ACs 777 passengers will be more likely to divert.

No one else posts their company fuel policies on the net, I am not going to start. It does offer us commercial advantage, and we know from doing charters for other airlines and when the bring up their flight plans and fuel to be carried we see a difference.

You are more than welcome to apply for a job with us, and if successful, you would get access to the information.

Quoting BoomBoom (Reply 80):
You ave a very selective memory. If you haven't seen A340s diverting, maybe it's because your'e just not looking.

340s do divert, we had one recently, however the reason for the divert had nothing to do with the aircraft. I have never had to cancel a flight, or divert on a 340 for a aircraft related problem.

As for the stats Randy was quoting there is was found he was bending the truth a little, at the time the 777 was flying much shorter sector times than the 340, for every 2or 3x777 sectors the 340 would do 1, when you look at the stats it seemed worse, but if normalized over the flight hours they were similar.

We had a thread on this a few months back

In our airline the 330/340 has a lower diversion rate, and higher dispatch reliability than the 777/747.

Quoting BoomBoom (Reply 80):
What does a cracked windshield have to do with ETOPS?

Very little, but say a loss of generator in flight may cause a diversion, re-clearance over a non-etops path, where you would not have that problem on a quad.

Quoting XT6Wagon (Reply 86):
Given that ETOPS is going away and being replaced by LROPS, Er... the number of engines is near meaningless in the near future. No longer will Airlines be able to take you to the most remote parts of the world with only a minimum of fire suppression, or w/o impeccable MX. Now they will have to follow the same routes as a 777, and have the same fire suppression and MX.

LROPS at the moment is a FAA only thing, it does not have the international aviation support.

Quoting Widebodyphotog (Reply 96):
An open window at 470kts would likely kill or severely injure the crew...instantly between the high velocity material blown at them and the subsequent depressurization it's hard to imagine that being a surviavable event. Just IMO...

What civil aircraft do have an IAS of 470kt ? In cruise we do not sit that far above the max IAS to open the cockpit window.

Quoting Viscount724 (Reply 100):
I assume the record for the longest single-engine ETOPS diversion remains the UA 777-200 en route AKL-LAX on March 17, 2003, that shut an engine down and diverted to Kona, Hawaii.

I was of the understanding it was up around 193 minutes.

Quoting Pygmalion (Reply 101):
Any pilot that says he doesn't trust statistics should be raising goats not flying.

Another statistic for you, most of the remote ETOPS alternates do not appear on any travel agents books, they tend to have some of the worst weather, and no facilities.

Quoting KrisYYZ (Reply 104):
The GEnx engines would already be in the fleet on the B787s and there would be flight deck commonality advantages as well.

No flight deck commonality between the two, the 748 will have commonality with the 744.

Quoting 777law (Reply 105):
quieter

That is BS.

Quoting Antskip (Reply 106):
The above is the sort of use of "hard facts" / statistics or whatever that is a problem. To argue that statistics shows (and so does logic) that having half as many engines halves the likelihood of engine failure is fraught with problems. The logic also means that a single is twice as unlikely to have engine failure as a twin. But the implication that having statistically half the chance of engine failure somehow makes a twin more than a match for a quad, in the safety stakes over areas far from land, is problematic. Though a single may be 4X as unlikely to have engine failure as a quad; if that were to happen, it is the end game for the single (now zero) there and then. Similarly, though a twin is statistically only half as likely to lose an engine as a quad, it then finds itself in the position of a single - with no redundancy left

What I dont like about twins in remote areas is the lack of options, on a quad, with a failure for a non-critical emergency with an engine shut down, I can make it to a company port on 3 engines. We can look after the aircraft, and the people better at those ports, and the airport is a known quantity.

With a twin on say a north pacific operation, we have no experience into the diversion airports, many of which have horrible weather, crosswinds exceeding aircraft limits, lack precision approaches to all runways, with some other non trivial phenomena like severe mountain wave turbulence and high terrain.

Another factor people seem to forget is that it is the technology in the engine which is a factor in its reliability, not the number of engines installed on an aircraft. I would fully expect a A380/748i to have a lower IFSD rate than a 777 due to the newer engine technology, just like I expect a 744 to be more reliable than a 707 or 747-100/200.

Quoting SEPilot (Reply 118):
There has never been a jet transport that has suffered two unrelated engine failures on the same flight, and that includes all the quads flying before ETOPS was invented. That is why ETOPS was considered practical to begin with.

There has been, El Al 747 for example. One of our related companies has had two unrelated failures within the engine systems on a etops twin, and were lucky to get the aircraft on the ground before the second failure became worse.
 
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SEPilot
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 10:13 am

Quoting Zeke (Reply 147):

There has been, El Al 747 for example. One of our related companies has had two unrelated failures within the engine systems on a etops twin, and were lucky to get the aircraft on the ground before the second failure became worse.

I would like to find out more about these incidents; can you point me to details? I do know about the El Al 747 that crashed in Amsterdam, I believe, after one engine had an uncontained failure and the debris took out the adjacent engine; but this does not qualify as unrelated failures.
 
ACDC8
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 12:28 pm

Quoting BoomBoom (Reply 136):
The were not in any violations of of BA company policy or CAA rules. However, the FAA wanted to fine them or operating an "unairworthy" plane.

However, if the aircraft was indeed unairworthy, the FAA should have not had a problem take action against BA and/or the crew. Since they couldn't fine them, I'm assuming the aircraft was airworthy as far as regulations is concerned.

Quoting BoomBoom (Reply 136):
Quads have more options in an engine out scenario, but this doesn't overcome the disadvantages of quads. Twins are clearly superior, which is why the 777 outsells the A340 by such a large margin and Airbus is planning to replace the A340 with a twin A350.

Superior seems a bit extreme of a word, effiecient or markatable would be a better description. Are there not more reasons other then the fact that the T7 is a twin, why it's outselling the A340, such as payload?

Quoting Jacobin777 (Reply 137):
if it were a twin, it had a less possible chance of "engine-out"....

I'm not to sure about that one ...  Wink

Quoting Jacobin777 (Reply 137):
even if it had to return, the benefits far outweigh the consequences....

Not necessairly, as in the example with the BA 747 last year, the financial consequences continuing on it's destination.
 
BoomBoom
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 3:24 pm

Quoting Zeke (Reply 147):
No one else posts their company fuel policies on the net, I am not going to start.

No one asked you to. No one cares. You're the one who introduced it to the thread, but it's irrelevant.

Quoting Zeke (Reply 147):
In our airline the 330/340 has a lower diversion rate, and higher dispatch reliability than the 777/747.

Right. Tha'ts why they're dumping the A340 in favor of the 777.

Quoting ACDC8 (Reply 149):
However, if the aircraft was indeed unairworthy, the FAA should have not had a problem take action against BA and/or the crew. Since they couldn't fine them, I'm assuming the aircraft was airworthy as far as regulations is concerned.

Wrong. They could fine them. They just choose not to.

Quoting ACDC8 (Reply 149):
Superior seems a bit extreme of a word, effiecient or markatable would be a better description.

It's superior. The sales data proves it.

[Edited 2007-03-07 07:29:13]
 
XT6Wagon
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:01 pm

Quoting BoomBoom (Reply 150):
Quoting ACDC8 (Reply 149):
However, if the aircraft was indeed unairworthy, the FAA should have not had a problem take action against BA and/or the crew. Since they couldn't fine them, I'm assuming the aircraft was airworthy as far as regulations is concerned.

Wrong. They could fine them. They just choose not to.

agreed, They decided to not fine them for 2 reasons. It wasn't against the letter of the law. They were allowed to by the "higher ups" in BA to continue when they discussed it with dispatch.

The FAA I think correctly slapped some wrists at BA, and then told everyone they would hang anyone else pulling that kind of stunt out to dry if they saw it happen again.

There is a VERY good reason to not continue on to another airport in a quad other than the nearest SUITABLE airport.... If an engine just drops dead on you... you don't really know the exact cause. Nothing says fun like a second engine going dead because the diagnostics have had the courtesy of also packing it in, and reporting everything fine while in fact both engines on that wing have 0 oil in them. Do you want to be in the middle of nowhere on a 747 or A340 with 2 engines out and in the middle of nowhere when the 2nd goes dead? Do you want to be there because people assume just because it can fly at near full normal altitude and speed that its fine? Or do you want the plane to divert and land just in case it isn't something that IS going to affect all the engines on the aircraft? As stated in posts above there have been cases where multiple engine failures happened thanks to bad MX. In these cases the time for each engine to drop dead can differ wildly even with equal starting conditions.

I think its only a matter of time before EVERYONE forces 4 engine aircraft to meet ETOPS regulations due to the extra safety from doing so.
 
jacobin777
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:17 pm

Quoting ACDC8 (Reply 149):
Quoting Jacobin777 (Reply 137):
even if it had to return, the benefits far outweigh the consequences....

Not necessairly, as in the example with the BA 747 last year, the financial consequences continuing on it's destination.

but the B747 had to divert in the end anyway.. Wink

Quoting ACDC8 (Reply 149):
Quoting Jacobin777 (Reply 137):
if it were a twin, it had a less possible chance of "engine-out"....

I'm not to sure about that one ... Wink

1/2 the number of engines, 1/2 the number of possibilities... Wink

Its like having 3 boys in a row..the probability of having a child either a boy or a girl is 50/50, but the probability of having 3 boys in a row is 1/2^3, which is 1/8=12.5%
 
ACDC8
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RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 5:42 pm

Quoting BoomBoom (Reply 150):
Wrong. They could fine them. They just choose not to.

Could you provide a link to that, I would appreciate it. From what I have read, including the links you have provided, no regulations were violated. While the aircraft was flying over US airspace, the CAA superceded the FAA given the fact that the aircraft belonged to BA, however, BA did agree to change it's policies as per the FAA's recommedations. Am I missing something there?

Quoting BoomBoom (Reply 150):
It's superior. The sales data proves it.

Sales data does not make something superior. More markatable yes and a better (sales) performer yes. I still feel that the word superior is a little extreme in this sense.

Quoting XT6Wagon (Reply 152):
There is a VERY good reason to not continue on to another airport in a quad other than the nearest SUITABLE airport.... If an engine just drops dead on you... you don't really know the exact cause.

I agree with that completely, just wanted to make sure that I did understand that a quad does have more options availabe then a twin. Safety should always come before economics, there is no question about that.

Quoting Jacobin777 (Reply 153):
but the B747 had to divert in the end anyway..

True, but as you said, in the end, a good 8 hours in the end.

Quoting Jacobin777 (Reply 153):
1/2 the number of engines, 1/2 the number of possibilities...

Its like having 3 boys in a row..the probability of having a child either a boy or a girl is 50/50, but the probability of having 3 boys in a row is 1/2^3, which is 1/8=12.5%

Now we're getting into statistics and mathamatical speculations. Interestingly though, one of my flight instructors told me that a twin-engined aircraft is more likely to have an engine out as opposed to a single. If that's true, I don't know, but quite an interesting theory.
 
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ADent
Posts: 1222
Joined: Fri Dec 22, 2006 12:11 pm

RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 6:41 pm

My guess the big issue on the 3 engine BA 747 is what would have happened if they lost a second engine at the midpoint of the Atlantic crossing or even early in the flight while over mountains while heavier.

-----

There are now single engine airliners - mostly turboprops and only in some countries.

-----

A 747 is twice as likely as a 777 to have an engine failure, in general. This is one reason why Lindbergh chose a single engine for his Atlantic crossing - a twin or quad was much more likely to have an engine failure.
 
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zeke
Posts: 16447
Joined: Thu Dec 14, 2006 1:42 pm

RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 7:24 pm

Quoting BoomBoom (Reply 150):

No one asked you to. No one cares.

For those childish remarks, I will ignore any further questions from you in the future.

Quoting XT6Wagon (Reply 152):

The FAA I think correctly slapped some wrists at BA, and then told everyone they would hang anyone else pulling that kind of stunt out to dry if they saw it happen again.

QF did it two weeks later. What BA did was perfectly legal, the very same BA aircraft had an engine failure on the same engine two weeks later and flew SIN-LHR no probs. Many many US flagged carriers have flown one engine inoperative in piston, turboprop, and jet tri and quads in past years.

You may want to consult the FARs, as it is in black and white that it is allowed under part 121, the BA flight was part 129. The UK CAA investigation into the incident said no rules were broken in respect to the decision to continue.

Quoting XT6Wagon (Reply 152):

There is a VERY good reason to not continue on to another airport in a quad other than the nearest SUITABLE airport.... If an engine just drops dead on you... you don't really know the exact cause.

With our aircraft people can actually log on remotely and have a look at the systems, BA have a similar system.

Quoting XT6Wagon (Reply 152):
Do you want to be in the middle of nowhere on a 747 or A340 with 2 engines out and in the middle of nowhere when the 2nd goes dead?

340 can happily fly with 2 inoperative, even at MTOW, something I am yet to see a 777 or 330 do.

Quoting XT6Wagon (Reply 152):
I think its only a matter of time before EVERYONE forces 4 engine aircraft to meet ETOPS regulations due to the extra safety from doing so.

The 340 has all the ETOPS systems of the 330, in our case the oxygen system on the 340 is actually better than the 330.
 
musapapaya
Posts: 1041
Joined: Mon Apr 05, 2004 10:02 am

RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 10:21 pm

Quoting Zeke (Reply 156):
340 can happily fly with 2 inoperative, even at MTOW, something I am yet to see a 777 or 330 do.

Hi Zeke

I would be a bit curious - if two engines on one wing fails, is the senario gonna be different if one engine on each wing fails? If two engine on one side dies, the thrust will be very assymetric. Am i right?

William
 
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zeke
Posts: 16447
Joined: Thu Dec 14, 2006 1:42 pm

RE: 777 Vs. A340 - AC CEO Comments

Wed Mar 07, 2007 10:34 pm

Quoting Musapapaya (Reply 157):


I would be a bit curious - if two engines on one wing fails, is the senario gonna be different if one engine on each wing fails? If two engine on one side dies, the thrust will be very assymetric. Am i right?

Yes,

The rudder is sized for an engine failure on takeoff or for the failure of slats on the wings, this gives more rudder control than what is required for two engines out in the cruise.

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