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Boeing 777X Vs. A340-500/600

Wed Jun 16, 1999 10:58 pm

The A340-500/600 is underway with first delivery in 2002, and Boeing is about to make a decision on the 777-200X/300X very soon. The aircrafts are very similar to each other in range/passenger load characteristics. Is the 777 a more economical business proposition given that it has two engines and thus lower operating cost? If authorities decide to increase ETOPS limit to 207 min vs. the current 180 min. , does anybody know if Airbus will be inadvertently affected by this decision?
 
wingman
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RE: Boeing 777X Vs. A340-500/600

Thu Jun 17, 1999 1:05 am

I'm not sure about the effect on the Airbus models, but take a look at the pax survey Boeing released today in Paris. You can find it in Yahoo or right here I'm sure. These surveys can be manipulated to a degree, but it is difficult to ignore the numbers. 77% of 6000 European pax surveyed prefer the 777 to the 330/340. That number is huge when you think about it. The survey was conducted by 5 Euro lines and one Middle Eastern airline flying to Europe (probably Emirates since Boeing knows they love the 777). Passengers had to have flown both types in the past two years. Boeing coordinated the survey, but even so, its hard to manipulate the data beyond a 10% differential. Political pressure aside, and barring any ETOPS scares, the logical choice is the 777. I just want to stand beside the new RR 115K thrust brutes if/when the 777X appears.
 
mirage
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RE: Boeing 777X Vs. A340-500/600

Thu Jun 17, 1999 3:53 am

Yes, Airbus will be affected because that decision will permit reroutes on crossings made by the 777, saving money and time to airlines operating with the 777. In Airbus opinion, the FAA will soon increase ETOPS to 240 minutes wich is bad news for the A340-500/600. This aircraft will not be able to compete with the 777 on the Pacific routes.
Could this be the FAA protecting Boeing......?

Luis, Faro, Portugal
 
Guest

RE: Boeing 777X Vs. A340-500/600

Thu Jun 17, 1999 6:18 am

I prefer to see the FAA/ETOPS debate as being driven by Boing, stronly supported by airlines, but also based on strong statistical information.

The FAA is the aviation regulatory body in the US but it is also the promoter of aviation so it has an almost schizophrenic role. This dual role is often debated by groups such as the National Transportation Safty Board who makes recomendations to the FAA on safety matters. The NTSB is often frustrated by the FAA's cozy relationships with the airlines and airplane manufacturers. It is no surprise to me to see the FAA taking this action.

Even though approving 240 minute ETOPS can be seen as FAA favoritism, I believe it is based on good reliable information and in this case should not put lives at risk.

Boeing has a good overview of ETOPS in the online AERO magazine.
 
william
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It Only Needs To Happen Once.

Thu Jun 17, 1999 7:46 am

The 777 is a technical marvel. But if I am flying to Asia from the USA,the aircraft is going to have at least 3 engines. Ask yourself this question,honestly,and put aside your Biases,if you midway in your Asia bound flight and for some unexplained reason(and yes I have read the various reports on how this is rare) the pilot needs to shut down one engine,which aircraft,A340 or B777,are you going to feel more comfortable in? Now imagine how the uneducated are going to feel when this happens.
 
Guest

Good Point, William

Thu Jun 17, 1999 9:25 am

You do make a good point, from the standpoint of the average traveler there is a confidence in three or more engines. The question is if the extra engines are worth the maintainance and weight penalty compared to the small chance that they will be absolutly necessary to safety operate on the routes in question.
 
Lufthansa
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RE: Boeing 777X Vs. A340-500/600

Thu Jun 17, 1999 10:44 am

Well, i personally have never flet concerned on an etops flight, the thing that interests me here is maintances costs. On long haul, this is suppose to be the area the quad has the advantage in. Fuel consumption for the quad jets are suppose to be better as the are closer to their ideal operating efficiency. But we are probably only talking a few percet here. Now this is important if range is the issue at hand, but, if both the twinjet and the quad can reach the desired destination, a few percent difference in fuel consumption isn't really all that important if you can save a few percent in maintaince costs on the engine. Remeber that 777 engines are not exactly going to be the easiest engines in the world to perform maintaince on - the sheer size of them i think would require a bit more time to work with than most engines. It certainly is going to take much more labor than a cfm56 or a rb211, which i think is the closest thing we've got to compare to the new trent 500 engine. I think TAAG747 is right here about Etops. Where i think the question lies, is, what is more expensive, the extra fuel a twinjet would consume, verse, the extra maintance cost of a quadjet? On the long haul, does a twin really give lower operating costs than a quad jet? Fuel burn, id say for sure, the quad is more efficient, but, engine maintaince? Ive got a feeling that 2 777 engines are going to cost just slightly less than say 4 50 000 lb thrust class engines. What does this mean for the 747-400? Perhaps the end if a long range 777-300 enters service? Id say we are all going to have to wait until both types are in service to get the answer. But, my feeling is, that unless fuel prices rise a lot, the end cost is going to be about the same.
 
BryanG
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Fuel Efficiency

Thu Jun 17, 1999 2:47 pm

A while ago in Aviation Week magazine I read that the 777-200 actually burns a comparatively lower amount of fuel on a long flight than an A340-200. I also thought that the quad would have better efficiency, but it said that the 777 gave about better efficiency than the Airbus. I don't remember the exact percentage increase, but it was less than 10%. Not a drastic difference.
 
FLY777UAL
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Lufthansa

Thu Jun 17, 1999 4:05 pm

Why would a twin consume more fuel than a quad? You have two engines to drive in the twin's case...unlike four in the quad's case.

FLY777UAL
 
Guest

A Brief Comparison-777 Vs A340

Thu Jun 17, 1999 4:11 pm

I think majority of airlines are drooling over a340-500s/-600s instead coz of several reasons:

1. A340-500/-600 offers more range than early 777-200/300X proposals (few montsha go Boeing said the -200X will have a range of 16,000km)

2. Common crew rating-looking at swissair and lufthansa for example, they are nearly all arbus fleet and new A340s meant cross crew flying.

3. A340 requires No ETOPS-Boeing's -200X/-300X requires too much complciated crap such as ETOPS, that's the downside of the 777X series.

4. Airbus offers garuntee delievery dates-whereas Boeing always deliver late :-(

Considering such comparions, I reckon Boeing will still aboe to capture the A340-500/-600 market because the 777 is a very very capable aircraft, and I reckon ETOPS is not a major problem because the engines used are already very very advanced, adding that better versions are proposed.
 
Lufthansa
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Fly777ual

Thu Jun 17, 1999 4:24 pm

Okay, for this fly777ual you need to make a few assumptions. One is, that both engines types being compared are roughly technologically equal. Okay the reason why a quad jet in theory burns less fuel over long haul flights is simple. On a quad jet, each engine must have 25% excess thrust. And, on a twin jet, each engine must must have 50% excess thrust. This means, that, a quad jet is operating much closer to its ideal efficieny in cruise. But, it doesn't stop there. The wing structure of a quad jet is simplier, and lighter, and doesn't require as much re-enforcing as a twin jet, as the engines weight are distributed more evenly across the wing, and the extra weight further out on the wing from engines 1 and 4 help combate the wing's upward flex, thus, it doesn't have to be as strong, and can be built ligher and simplier. It really only makes a difference over long haul flights. (you have a higher maintaince requirement, and in some cases the 4 engines total weight is greater than the alternative 2 engines)

BryanG - about A340-200 vs 777-200 fuel burn. That must be on a per seat basis. The A340-200 is significantly smaller than a 777-200 - a lot smaller. Naturally, with size, comes efficiency - so we should expect that the 777-200 burns less per seat than any significantly smaller aircraft. It is interesting that the article did not make a comparison with the larger A340-300 - which, although still smaller is closer to the 772's capacity. Regardless, as the boeing charmain regularly points out, fuel consumption is typically about 10% of operating costs, so, you can have a hudge saving, such as 20%, and that only translates into about a 2% overall operating cost saving. This is why airlines aren't getting too worried about it.
 
FLY777UAL
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RE: Fly777ual

Thu Jun 17, 1999 4:52 pm

Okay...now I get it! I was wondering why CX said their A340's were better suited than 777's on the long hauls!

Thanks, LH!

FLY777UAL
 
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CV880
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Quad Vs Twin - Another Aspect

Thu Jun 17, 1999 10:25 pm


The comments form Lufthansa regarding wing structure are interesting, but there is another aspect of the 2 vs 4 thing that I heard from an AA employee a few years ago when AA was selecting the 777. The comments, if true, indicate that AA favored a twin for potentially better dispatch reliability. The idea is that if at least one engine on an a/c is squawky, the flight cannot push back, and with four engines, there is twice as much chance for at least one engine to cause a problem.

Of course, this assumes that the CFM56 and the 777 engines, taken as individuals, have the same probability of going kaput.

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