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JayinKitsap
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 3:24 pm

Quoting PolymerPlane (Reply 45):
You don't even know what he uses to come up with this numbers. If you care enough to read other people's comment, widebodyphotog DOES NOT solely use the payload-chart to come up with this numbers. He actually uses computer program generally use in aviation industry to come up with this numbers, with actual flight parameters.

I think you should sit down and be more careful before criticizing one's work. Do you think you're the only one in this forum that has actually analyze his work?

I would give someone with as high of a respect rating as WBP some benefit of the doubt. I believe it was pointed out back during the 747 ADV discussions that WBP uses a good but not the best mission planning system with the best systems used by the airlines themselves. Some of the differences were pointed out between WBP and some other posters that do mission planning. (Was it Zeke?) SFC and plane performance changes throughout the flight, but the modelling done by the system varies between systems with the simpler programs having fewer stages for the climb than the fancier systems, etc. However, it is my understanding that WBP works in fleet planning where his customers are making the decisions on which planes to buy.

It appears to me that his charts are some of the best available in the public domain for many of the airlines. Of course, any analysis is limited by the available data. For example, very little data on the 350XWB performance has been made available to planners outside of Airbus. Meanwhile, a lot is known on the 330 and 777.

I think on the referenced comparision every attempt was made to match up the total payload (pax + bags + cargo + crew) were the same and the distance flown also the same so fuel consumption is comparable. Yes, at a differnent payload or range, the fuel consumptions are different. For example he compared the 777LR with the ER models and showed that the LR made economic sense to use on flights over 5,000 nm (as I recall) but not on shorter flights as its cruise is optimised but the climb portion is less efficient than the ER wing.
 
manny
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 3:47 pm

[quote=WorldTraveler,reply=44
[/quote]

For the aviation enthisiast in me its a few points to ponder.
 
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autothrust
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 6:06 pm

Quoting Zeke (Reply 6):
I dont know about the particular mission, I would disagree that its 20% across the board.
Indeed this Numbers arent true    , have readed several sources (wich i dont have time to find now) andits proved only 7 - 10% (not HGW version). There are missions a A340 can be very efficient. As passanger i would take the A340 any day over the 777 because quiter cabin. We should also take in consideration the afford price.

[Edited 2006-09-20 11:13:51]
Flown on: DC-9, MD-80, Fokker 100, Bae 146 Avro, Boeing 737-300, 737-400, 747-200, 747-300,747-400, 787-9, Airbus A310, A319, A320, A321, A330-200,A330-300, A340-313, A380, Bombardier CSeries 100/300, CRJ700ER/CRJ900, Embraer 190.
 
phollingsworth
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 9:21 pm

Quoting Aviator27 (Reply 36):
I'm sorry but your analysis still doesn't pass the logic test. How can two airplanes burn the same amount of fuel for 7200 nm and then one of them burn 20% more in the remaining 1900 nm (9100 nm -7200 nm = 1900 nm). Like I said, your analysis is just flawed.

I never said the charts were correct, they can have errors. The problem with using the payload-range is that you have to find equilivalent points to compare. For instance a given payload or zero fuel weight to a given range, this is not a trivial task given the resolution of what is typically published. Anyhow, I made a math mistake in my previous posting, the 777 has a fuel burn advantage at the same payload and range of 7200 nm. The problem is that I think the charts that I have for the 340 are wrong.

Quoting Aviator27 (Reply 36):
You still cannot use any range charts (whether max range or payload range) to calculate trip fuel. I don't have charts I can link online to provide any data. Your information is wrong and you need to delete them.

As long as the rules that were use to produce the chart are provided you can use payload-range charts to calculate mission fuel. Of course the charts themselves can have errors, I never denied that. They may also be lacking enough resolution to make an honest comparison, but if you can align your assumptions you can use them. Calling my information wrong is irresponsible without providing details as to why they are wrong. The simple fact of the matter is that if you and I start out with different reference frames, which is quite possible, making a determination as to who is correct and who is incorrect is virtually impossible.

Quoting Aviator27 (Reply 36):
Period

That is an absolutist and dangerous statement to make, especially without supporting evidence, if you are wrong here you loose all current and future credibility.

Quoting Aviator27 (Reply 36):
Its hard to find a system with both B777-200LR and A340-500 figures loaded into the flight planning computers.

Please do, though these models also have errors.

Quoting Aviator27 (Reply 36):
Check what Emirates Clark said about the economics of both airplanes (he said they were almost identical).

Assuming you have remember what Mr. Clark has said correctly (we can verify the validity of this assumption later). This statement very well could be correct. However, this has nothing to do with whether of noth the 777 has a fuelburn advantage. It includes a whole host of costs, and most importantly and assumed discount rate, which I garuntee he never quoted. Anyhow what holds for Emrites does not hold for Air Canada or any other airline.

A quick note on payload. Payload is payload, what the physics cares about is the weight, that is what the lift needs to counter etc. You should always compare fuel-burns for missions based on payload weight. Each airline has the oportunity to fit out their aircraft as they see fit, this will change the number of pax and the actual OEW. However, the typical basic OEWs provided by the manufactures use fairly similar assumptions, meaning any changes that airlines make (which typically increase OEW) can be seen as removing revenue payload potential.
 
worldtraveler
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 9:36 pm

Quoting PolymerPlane (Reply 48):
SQ flies A345 directly to EWR, never to JFK. JFK flight is a 744 with a stopover in FRA. I just checked the online booking, SQ 21 and 22 SIN-EWR are still on the market.

ah... you're right.... I still have JFK on my mind for that flight.

But SQ has acknowledged the flight loses money as does its LAX-SIN flight.

I still have seen no practical evidence that a twin can't fly an important route that a quad could fly.

And no one has yet to address the US government's movement toward standardized rules for extended over water flights regardless of the aircraft. The whole twin vs. quad thing is becoming worthless.

Put that w/ a quad's inherent fuel disadvantage vs a twin for the same amount of thrust and it's easy to see why Airbus finally caved on creating a ULH twin.

For the 748 and A380, there is no engine that could produce half the thrust needed for those planes but that is not true for the A350 or 777. Available thrust and limitations of a particular engine are two very different things.

It's very immature to dismiss someone else's point of view just because you don't agree w/ it. I suggest you step away from the computer and talk to people; you'll quickly find that if you talk to people in person the way you talk to them over the internet, you won't have many friends. But maybe that's why you post here.
 
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zeke
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 10:06 pm

Quoting WorldTraveler (Reply 56):
But SQ has acknowledged the flight loses money as does its LAX-SIN flight.

I am not aware of that, I am sure the shareholders would be jumping up and down if that was the case.

SQ recently employed about 12 additional expat captains for that fleet, with 5 year contracts, not the sort of thing one would do if one was considering cancelling it.

Quoting WorldTraveler (Reply 56):
Put that w/ a quad's inherent fuel disadvantage vs a twin for the same amount of thrust and it's easy to see why Airbus finally caved on creating a ULH twin.

Please see my post above, the 748i will have a lower CASM over ANY twin Boeing produce.

Airbus could not make the 330 into a ULH aircraft as the landing gear clearance prevented installing engines with the required thrust. The elected to further develop the 340, which had a development cost much lower than the 777.

The main problem with the 345/346 is the TFSC of the engines is several years behind the GE90-115B. Put Trent 1000 based powerplants on the wings the economics go back to the 345/346.

You are comparing a product that was brought to market after another, like trying to compare a 707 to A330. Put a CFM56 on a 707 or DC8 the economics improve, its a later engine technology.

I see a similar STC being applied to the 744, extending its life some years.

Basically the same reason why the 350 will have improved economics over the 772, it has later engine technology.

Quoting WorldTraveler (Reply 56):
I still have seen no practical evidence that a twin can't fly an important route that a quad could fly.

Depends on what your definition of important is.... Quads do have design advantages, if you cannot see that, I am sure you have access to a library where you can get hold of some aircraft design books that will enlighten you.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
irobertson
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RE: A345 And 772LR Fuel Burn.

Wed Sep 20, 2006 10:39 pm

Quoting Stitch (Reply 24):

And as an aviation enthusiast, I am pleased that I have been able to see all three models in person.

Welcome to my Respected Users List. Your post was really nice to read.

Quoting Zeke (Reply 57):
You are comparing a product that was brought to market after another, like trying to compare a 707 to A330. Put a CFM56 on a 707 or DC8 the economics improve, its a later engine technology.

And what a difference those CFMs made to the DC8! I was curious as to whether the HGW upgrade would include a newer engine that would help it compete with the 777LR a little better.

There was a thread once about what aircraft would be around in 30 years time from today that would be called "classics". I think the 340 series is really turning out like the DC8 in many ways...
 
worldtraveler
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 12:04 am

I’m not doubting that the 748 will be the most economical aircraft in the world…size does have advantages.

I’m also not doubting that quads do have some advantages… the primary one, though, is size. Twins simply can’t lift the mass of an A380 or 747.

But there are engines that can do most of what every variant of the A340 has done and that is why you see a handful of each version having been produced and none of them have been well received in the market compared to the 777.

I’m not interested in arguing but Airbus has made some major strategic blunders including believing that twins could not serve long, heavy overwater routes as well as believing that the ULH market is built around hubs. If you don’t see Airbus’ mistakes and that Boeing was right, then you simply are too loyal to Airbus to see the truth. But it’s precisely what Boeing is beating Airbus’ tail in the widebody market while Airbus has virtually nothing that is competitive to offer the market now.

As for SQ, we all know SQ is no different from any other airline in operating flights that are not profitable. Since other carriers are operating nonstop from JFK to SE Asia, SQ has no choice but to do the same. It doesn’t mean they are making money.

Oh, and if you aren’t aware of SQ’s comments, I’d suggest you head for the library and find what SQ has said about their ULH operations.
 
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zeke
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 12:33 am

Quoting WorldTraveler (Reply 59):
I'm not interested in arguing but Airbus has made some major strategic blunders including believing that twins could not serve long, heavy overwater routes as well as believing that the ULH market is built around hubs. If you don't see Airbus' mistakes and that Boeing was right, then you simply are too loyal to Airbus to see the truth. But it's precisely what Boeing is beating Airbus' tail in the widebody market while Airbus has virtually nothing that is competitive to offer the market now.

You seem to have a one sided recollection of history, who put twins on the north Atlantic first ?

When the 340 first came out, no power-plant was available to do the job as a twin, you may think they are not well received by industry, that is you opinion, the 42 operators that have them would disagree.

Quoting WorldTraveler (Reply 59):
As for SQ, we all know SQ is no different from any other airline in operating flights that are not profitable. Since other carriers are operating nonstop from JFK to SE Asia, SQ has no choice but to do the same. It doesn't mean they are making money.

SQ being one of the most profitable airlines in the world, I guess they need to take notes from US airlines like AA, UA, and CO on how to operate unprofitable routes.

You have not said anything factual on this thread so far....
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
airbazar
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 12:45 am

Quoting WorldTraveler (Reply 56):
But SQ has acknowledged the flight loses money as does its LAX-SIN flight.

Never heard such a rumor. I think your're thinking about TG and their A345 BKK-JFK-BKK flight. The only thing I've heard is that SQ and especially their customers would like to have their premium F product in their A345's but they can't.
 
Lemurs
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 12:49 am

Quoting Zeke (Reply 57):
I am not aware of that, I am sure the shareholders would be jumping up and down if that was the case.

SQ recently employed about 12 additional expat captains for that fleet, with 5 year contracts, not the sort of thing one would do if one was considering cancelling it.

Not every route needs to make money. I've heard elsewhere that SQ is losing money on those flights as well, but they don't care because they're important flights. (No source on that, so I'd believe just as easily that it's false.) Given how much we and the press talk about those flights, it's hard to disagree that SQ has gained some significant mindshare operating them, regardless of their operational profitability. It would not be the first or last time an airline has operated a 'prestige' flight for the sake of investing in long-term growth in a big market. NYC and LAX are the two biggest metropolitan markets in the US. Using them as your "loss leaders" because of percieved growth potential is not a bad thing.

So just because they're still running the flights doesn't mean you can assume they're making money on it. It also doesn't mean you can assume they're losing money on it. Given the scaled down appointment on those 345's, it's probably safe to assume that they can't be making money if they're pulling in light loads, though. 75% of 188(?) seats, regardless of the price, is a big gap on such a long, expensive flight.
There are 10 kinds of people in the world; those who understand binary, and those that don't.
 
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Stitch
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 12:50 am

Quoting Zeke (Reply 60):
SQ being one of the most profitable airlines in the world, I guess they need to take notes from US airlines like AA, UA, and CO on how to operate unprofitable routes.

To be fair, SQ's route structure and competitive landscape is very different then that of the US "Big Six" domestic carriers. This takes nothing away from SQ's dedication to superlative service and execution excellence which has been instrumental in their success.

However, if SQ operated large widebodies, medium widebodies, large narrowbodies, and small widebodies performing hundreds of flights a day around Asia and the world, with hubs in SIN, NRT, SYD, and HKG against five other carriers of similar size doing the exact same thing, some with hubs in one or more of SQ's hub cities plus hubs in TPE, BKK, ICN, PVG, and PEK, all of which offer similar service levels, as well as having a number of LCCs operating with CASM upwards of half poaching their most profitable short-haul routes, would they be as profitable?
 
futurecaptain
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 12:52 am

Quoting Zeke (Reply 60):
You seem to have a one sided recollection of history, who put twins on the north Atlantic first ?

The RAF. In 1919 flew a Vickers Vimy on the first direct trans-atlantic crossing.

But seriously. The first ETOPS rating from the FAA was given to TWA in the 80's for service between St. Louis and Frankfurt. It was 90 minutes and on a Boeing 767.
AirSO. ASpaceO. ASOnline. ASO.com ASO. ASO. ASO. ASO. ASO.
 
Lemurs
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 1:02 am

Quoting Stitch (Reply 63):
However, if SQ operated large widebodies, medium widebodies, large narrowbodies, and small widebodies performing hundreds of flights a day around Asia and the world, with hubs in SIN, NRT, SYD, and HKG against five other carriers of similar size doing the exact same thing, some with hubs in one or more of SQ's hub cities plus hubs in TPE, BKK, ICN, PVG, and PEK, all of which offer similar service levels, as well as having a number of LCCs operating with CASM upwards of half poaching their most profitable short-haul routes, would they be as profitable?

A fact so often missed when people bash on domestic legacies. We have the most hyper-competitive aviation market in the world, with direct flights to hundreds of Int'l destinations from dozens of airports spread across the entire country. If you up and transplanted SQ's hub from SIN to JFK, they'd either fall apart in 5 years, or adapt to be more like a US legacy out of necessity. They simply could not continue to be SQ in the US. It has nothing to do with how good or bad their management is, it has to do with the competitive environment dictating business practice.

Note that means they also couldn't gamble on loss-leader flights. There is a reason no US airline has attempted anything remotely like a premium-only ULH route with a small subfleet of large jets. It's not because no one thought of it, but because it's an economic risk, and you need to be secure in your bottom line and ability to grow that market before you'd EVER take on such a risk.

[Edited 2006-09-20 18:06:44]
There are 10 kinds of people in the world; those who understand binary, and those that don't.
 
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keesje
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 1:04 am

Quoting WorldTraveler (Reply 59):
But it’s precisely what Boeing is beating Airbus’ tail in the widebody market while Airbus has virtually nothing that is competitive to offer the market now.

Lets not get carried away by PR and cash in on the future.

Airbus is ruling the 200-280 seat segment.

Boeing has a painfull production gab in that segment 2002-2008 and they know it.

Hopefully the answer: 787 will change that, but it is a little late to succeed the 767/757.

A330 production has been increased time and time again and A330 is the market leader until likely the 787 will take over that position, but not before 2009/2010.
"Never mistake motion for action." Ernest Hemingway
 
widebodyphotog
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 1:12 am

I know I'm jumping into the fray a bit late but I'd like to clear some things up which seem to have become points of contention. It's nice to know that people are referencing the information I've made available in the past and making use of it. As far as it's origin we use two computer packages here which are PIANO, mostly for modeling, and Lockheed Jet Plan service for real time flight planning on actual long haul flights. I assure you that PIANO especially is about the most sophisticated software package available at this time and I'm glad I did not have to spend the $15K or so that it cost to acquire...

The trouble is that arranging the incredible amounts of data that come out of a modeled flight plan to present in a forum like this is quite difficult and time consuming. Especially when I'm not getting paid for it. For example Jet Plan shoots out about 12-15 full pages of data for an individual flight plan. There is no way I can readily present the depth of that information here. PIANO outputs incredible amounts of data. For some of the 787 modeling wefve done with PIANO get about 45 pages of stuff! But the streamlined data I present is very clean and accurate to the extent of the parameters used...

As to the substance of this thread, well it boils down to this. For a given same range and payload the 777-200LR uses less fuel than the A340-500, a lot less. At similar ZFW the fuel burn differences reduce to single digits but because the typical OEW of the 777-200LR is 23t less than the A345, at same range and similar ZFW the 772LR carries a lot more payload. These points are detailed plainly in my data tables.

As far as operational issues ETOPS vs quads, for the long range Northern Polar routes in practice, say EWR-SIN, the ETOPS180 route is only 168nm longer than the great circle route. Furthermore the GC route is seldom the best time saving path because of typical winds on the route. In practice there is a time savings to be had using the 777-200LR on that specific route and under typical seasonal conditions it should be a 15-25 min advantage for the Boeing.

Itfs actually quite interesting to look at this segment SQ is flying with A340-500. Boeing has presented some claims which I believe have generally been misinterpreted by the public. Boeing says the 777-200LR can save 20% or more in fuel and offer 20,000lbs or more in revenue payload on that particular route. Thatfs basically true but itfs an either-or proposition. Yes, for the same payloads the fuel burn advantage is better than 20% on this route or similar, but if you are using the available extra payload that advantage drops to 5-10%. Payload costs fuel and there is no way around that, but the maximum fuel burn advantages of the 777-200LR can not be realized while simultaneously using the maximum available payload on a similar range route. However, even at higher payloads the fuel burn advantage over similar distances is notable.

As you go down the scale in terms of segment length the advantages remain and slightly increase for 777-200LR because at lower TOW the airplane can climb to higher altitudes earlier in the flight. The maximum fuel burn delta would be realized at distances and similar payloads that required TOW of 690,000lbs or less for the Boeing. With this it should be noted again that 777-200LR is a fuel limited airplane that requires TOW well below MTOW at design range and payload, while the A340-500 is a TOW limited airplane that requires MTOW at design ranges. So to increase range with commercial payload weights the 777-200LR can add more fuel to the limit of fuel tankage and still maintain commercially viable payloads in the 75-90,000lbs range, out to distances of 9,000nm or more. To get those ranges the A340-500 has to increase fuel as well, but at the expense of payload, and in service on routes like EWR-SIN SQ is realizing only 40-50,000lb payloads with the A340-500. Going out farther reduces payload dramatically. This is also detailed in my data tables..

One thing that is missing in all of this is the cost of the airplanes themselves. There has actually not really been a great disparity in the prices of airplanes that have been sold already, and the final prices have been fairly competitive. In this case fuel burn difference becomes more significant as the cost difference of the Boeing can be made up quite quickly. Look at it this way. If SQ were to replace the A340-500 on its longest routes and carry no additional payload the savings would be up to $20,000 per trip based on a current fuel price of $1.95/USG (Singapore Spot Market price this week). With the addition of maximum available payload the savings are cut in half but potential revenue increases from additional cargo payload more than make up for the difference. So on a single segment you have the potential of saving upwards of $15,000,000 a year for a pair of airplanes in operation or some greater or lesser amount of savings and increased revenue by taking advantage of additional available payload. Project those factors out over five years and the savings are very significant.

I guess the million dollar question is why hasnft SQ taken up the 777-200LR? To my mind it may be a smarter choice to go with the next generation midsize airliners at this time for their longest routes. They have an LOI for the A350XWB but Ifm not sure what their full intent of application is with that airplane and the airplane itself has yet to be defined. But looking at how the economics of 787-9 would work on their longest routes Ifd say there would be more than significant benefits. 787-9 used on SIN-EWR would be able to carry the same or slightly greater total payloads than the current A340-500. Trip times would be up to 30 mins faster and the fuel burn would be reduced by more than 60% per trip. Seating capacity is not greatly reduced and the economics of needing to use dramatically less fuel outweigh any lost revenue from fewer seats. I would guess A350XWB may be able to offer similar savings but so far wefve got no data to work with from Airbusc



-widebodyphotog
If you know what's really going on then you'll know what to do
 
BoomBoom
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 1:31 am

Quoting Keesje (Reply 66):
A330 production has been increased time and time again and A330 is the market leader until likely the 787 will take over that position, but not before 2009/2010.

You incorrectly assume that a plane has to be in service to be the market leader. Wrong.

It only has to be marketed to be the market leader. The 787 has already supplanted the A330 as the market leader.

Quoting Keesje (Reply 66):
but it is a little late to succeed the 767/757

I'd say it was timed just right, given the new technology it will use. It's the A380 and A350X that are late.
Our eyes are open, our eyes are open--wide, wide, wide...
 
WINGS
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 1:52 am

Quoting BoomBoom (Reply 68):
You incorrectly assume that a plane has to be in service to be the market leader. Wrong.

It only has to be marketed to be the market leader. The 787 has already supplanted the A330 as the market leader.

Are you fully aware with what you have just written? If not wake up and smell the coffee. The B787 still has to fly, pass certification and prove it self with airlines.

Until then try to walk before you run  Wink

Quoting BoomBoom (Reply 68):

I'd say it was timed just right, given the new technology it will use. It's the A380 and A350X that are late.

Rubbish and you now it. The A380 has plenty of aviation first being introduced.

Regards,
Wings
Aviation Is A Passion.
 
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Stitch
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 2:00 am

Quoting Widebodyphotog (Reply 67):
I know I'm jumping into the fray a bit late but I'd like to clear some things up which seem to have become points of contention.

And thank you for doing so, sir.
 
BoomBoom
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 2:34 am

Quoting WINGS (Reply 69):
Are you fully aware with what you have just written? If not wake up and smell the coffee. The B787 still has to fly, pass certification and prove it self with airlines.

As soon as a plane is offered for sale it is being marketed. It doesn't need to fly, pass certification or prove it self with airlines to be offered for sale. And in case you hadn't noticed, airlines aren't waiting for it to prove itself before siging firm orders.

Quoting WINGS (Reply 69):
The A380 has plenty of aviation first being introduced.

I never said it didn't. I said it was late. Boy, is it LATE!
Our eyes are open, our eyes are open--wide, wide, wide...
 
WINGS
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 2:43 am

Quoting BoomBoom (Reply 71):
As soon as a plane is offered for sale it is being marketed. It doesn't need to fly, pass certification or prove it self with airlines to be offered for sale. And in case you hadn't noticed, airlines aren't waiting for it to prove itself before siging firm orders.

Well BoomBoom, We are talking about market leader. In my eyes for a plane to acheive that recognition it has to prove it self. Something which it has not done.

Quoting BoomBoom (Reply 71):

I never said it didn't. I said it was late. Boy, is it LATE!

Well mate I have to agree with you 100% on that. It sure is late.

Regards,
Wings
Aviation Is A Passion.
 
worldtraveler
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 7:22 am

well done, widebody.

You got to it, but the realpoint is that the 777LRs greater payload capability will translate into more revenue generating capability. A plane has no future if the revenue generating by adding a seat cannot be justified by the increased fuel required to lift that seat.

I had calculated the 777 fuel cost advantage to be $15-20M yearly so, yes, the payback is very quick.

So, yes, the 777 just plain does what it is supposed to do much cheaper which is why it is the segment leader.

As for why SQ doesn't replace its 345s, the bigger question is what is the future of ULH flights. There haven't been a rush of orders for the 777LR I'm sure partly because the 787 and the A350 will be able to handle many ULH routes.

Boeing's challenge then is to make the 777LR viable up against new technology aircraft. Since the 777LR is the same aircraft structurally as the 777 freighter, there is a contingency that could be exercised if the LR's passenger costs fall off pretty quickly. Even without that option, though, the LR will still have very favorable capabilities when compared with the 787 and A350 so there will be niche markets for which the 777LR will be well suited.

There are things that Boeing can do to make the 777 more efficient and we have seen theads on their weight reduction program and their increased use of composite. And remember also that Boeing can use the same trick that Airbus tried to use for the original A350 - base much of the cost savings on an engine replacement. If Boeing eventually chooses to reengine the 777 when it reaches the end of its life cycle with new generation engines, it could keep those planes flying competitively compared with the 787 and A350, and help ease alot of airlines' fears about writing down some fairly young 777s.
 
BOE773
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 10:45 am

Quoting Widebodyphotog (Reply 67):

For a given same range and payload the 777-200LR uses less fuel than the A340-500, a lot less. At similar ZFW the fuel burn differences reduce to single digits but because the typical OEW of the 777-200LR is 23t less than the A345, at same range and similar ZFW the 772LR carries a lot more payload. These points are detailed plainly in my data tables.

What engine types were you using for the data?
 
PolymerPlane
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RE: A345 And 772LR Fuel Burn.

Thu Sep 21, 2006 11:15 am

Quoting BOE773 (Reply 74):
What engine types were you using for the data?

772LR only comes with GE90-110 (well it also comes with the -115, but it's basically the same engine with different electronic limitation IIRC), and A345 comes with trent 553

Cheers,
PP
One day there will be 100% polymer plane
 
widebodyphotog
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 3:34 am

Quoting BOE773 (Reply 74):
What engine types were you using for the data?

GE90-110B1 Engines for my analysis. the -115B1L produces only slightly more thrust for climb and cruise, so even if those were used the differences would have not been that great. Possibly 2-3,000lb fuel burn reduction over various long haul flights.

Quoting PolymerPlane (Reply 75):
772LR only comes with GE90-110 (well it also comes with the -115, but it's basically the same engine with different electronic limitation IIRC), and A345 comes with trent 553

Cheers,
PP

AC, AI, and BR have all confirmed that they will take delivery of GE90-115B1L powered ships. Better hot, high, and shorter field performance is the main advantage of using the more powerful engine set. A340-500 is available now with Trent 556 and IIRC there are six different weight variants of A340-500 available now. They all have different fuel capacities, OEW, and are available with Trent 553 or 556.

Incidentally the 777-200LR order book stands at 41 not including 23 -200LRF on order. A340-500 has 31 orders and all but 7 have been built.



-widebodyphotog
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Thorben
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 3:45 am

Quoting Widebodyphotog (Reply 76):

All the things you claim there have not explained why TG, EY or IT still went for the A345.
France 1789; Eastern Germany 1989; Tunisia 2011; Egypt 2011
 
Lemurs
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 4:07 am

Quoting Thorben (Reply 77):
All the things you claim there have not explained why TG, EY or IT still went for the A345.

Who said it had to? He wasn't claiming to explain why some airlines would choose one over the other, he was talking data. Sometimes immediate realities and other considerations dictate purchase decisons as well you know. Financing, availability, delivery dates, fleet commonality, pilot availability, politics. A less efficient airplane can still be the right choice for a particular airline...they just won't make as much money off it.
There are 10 kinds of people in the world; those who understand binary, and those that don't.
 
PolymerPlane
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 4:44 am

Quoting Thorben (Reply 77):
All the things you claim there have not explained why TG, EY or IT still went for the A345.

Yeah, but It has explained how AC, EK, and QR basically dump A345/6 in favor of 777LR.

Cheers,
PP
One day there will be 100% polymer plane
 
BOE773
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 4:49 am

Quoting Widebodyphotog (Reply 76):
GE90-110B1 Engines for my analysis. the -115B1L produces only slightly more thrust for climb and cruise, so even if those were used the differences would have not been that great. Possibly 2-3,000lb fuel burn reduction over various long haul flights.

Thanks Wdbyptg.

I'd like to see a detailed breakdown of how the airframe and engine manufacturers come up with their figs; but I guess this is proprietary for them.
 
worldtraveler
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 4:53 am

Remember the 345 was in service first. even with its shortcomings, it provided an advantage, even if it was a short-lived one.
 
Pihero
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 6:44 am

And now, another side of the story .
These enormous gaps in terms of fuel economics have always bothered me, so I went to an airline flight planning program. Though it may be less advanced than the one WBP uses, it is -has been- verified through the years, and for accuracy, very difficult to beat : it is checked everyday many times against real figures and results.
Unfortunately, the data for the A-345 are not available to me, so I used those of the A-343 and I put the 772ER vs 343 on a real sector, PAR-JNB-PAR, and the resulting figures become quite interesting :

1/-PAR-JNB with a 30T traffic load :
Distance 4845 Nm, planned alternate GBE at 193 Nm.
772ER :
OEW :150.3 ; ZFW : 180.3 ; FOB 76.1 ; Burn off : 67.2 ;sector time :10.02

343 :
OEW :136.8 ; ZFW : 166.8 ; FOB 79.5 ; Burn off : 70.6 ; sector time :10.12

So, in this instance, the 343 uses 3.4t more than the 772 ,an increase of 5.06 % for a 10 min extra flight time.
The 20% seem very far, especially if one assumes that the 345 is supposed to have better performance than the 343.

2/-JNB-PAR with a 30T Traffic load
Distance 4816 Nm, planned alternate at 80 Nm.
772ER :
OEW and ZFW are of course the same,
FOB : 74.5 ; Burn off : 67.2 ; sector time 10.07

343 :
OEW and ZFW are of course the same,
FOB : 77.8 ; Burn off : 70.5 ; sector time 10.22
The values are still very similar to those above, the b/o increase is now 4.9 % although the trip time has now increased to 15 min, due to the winds aloft.

Now comes the interesting bit :

3/-JNB-PAR max payload study :

A/- to-day's conditions QNH :1030 hPa , OAT : 17°c,
772 : Max Payload : 40.9 ;ZFW : 191.2 (Max 195) ;TOW :269.3 (Max :269.3)
343 : Max payload : 41.2 ;ZFW : 178.0 (Max 178) ;TOW :259.9 (Max : 271).
These figures confirm that the 340 is ZFW -therefore structure limited, but it is some 10.1 below its MTOW limit, which means it has the capability of flying an extra 750 Nm if necessary.

B/-STD + 15°c--> OAT : 24°c ; QNH : 1013 hPa
772 :TOW : 259.5, a drop of 9.8 tons from the conditions described in 3/. The limitation is of course a second segment climb.
343 : TOW : 259.5, a drop of a mere 400 kg from the condition 3/.The limitation is wheel speed.(That the two airplanes come with the same TOW value is pure coincidence)

Sorry for the long post ; the rubbishing of anything Airbus was getting on my nerves. These two airplanes are extraordinary tools and airlines executives are not as terminally dumb as a few of you have surmised.

Regards to all.

If Zeke could provide the same actual ops data for the 345, I would be overjoyed
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Stitch
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 6:57 am

Quoting Pihero (Reply 81):
So, in this instance, the 343 uses 3.4t more than the 772, an increase of 5.06% for a 10 min extra flight time. The 20% seem very far, especially if one assumes that the 345 is supposed to have better performance than the 343.

Well remember you are looking at a flight distance almost half of what Widebodyphotog was using. Flying those extra 4000nm requires a good deal more fuel, plus you need a good deal more fuel then that to lift the fuel you need to fly the extra 4000nm.

In Reply 42, FutureCaptain noted the respective fuel burn per mile for each plane. Now I don't know if that is an average or specific to cruise or whatnot, but the numbers they posted works out to a 25% lower rate per mile for the 772LR.
 
Pihero
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 7:25 am

That's exactly the point, Stitch
Why only offer one set of data that stretches the design of one airplane so that it looks awful ?
I was more interested in what we see in our everyday professional lives, to take all things into perspective.
My JNB example above just proves that in some cases - which happen a lot more often than people think - the 772 performance against the old 343 is not that sparkling. These cases relate to hot and/or high places where a twin will always perform very poorly against a quad (which by the way has been despised and ridiculed by the great majority of A.nutters). I happen to think otherwise, and by experience.

Quoting Stitch (Reply 82):
Flying those extra 4000nm requires a good deal more fuel, plus you need a good deal more fuel then that to lift the fuel you need to fly the extra 4000nm.

Agreed. But my figures above show that it can't go any further than Paris from JNB with more than 33 T payload.The 343 is basically unaffected by these same conditions. So what's the use of that possible extra range, then ?
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Stitch
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 8:18 am

Quoting Pihero (Reply 83):
That's exactly the point, Stitch. Why only offer one set of data that stretches the design of one airplane so that it looks awful?

I don't believe Widebodyphotog choose numbers that specifically make the A345 look awful. He provided identical payloads and identical distance. It's just a fact that the A345 has a higher OEW and less efficient engines (in terms of total consumption vs. total thrust). So the 772LR should always have an advantage, but that advantage will fluctuate with the mission length and the mission payload.

In this particular case, it's 20%, but I think we have all been careful to qualify that statement that it was only for this particular case and could not/should not be implied that it will always be 20% for any mission. We're not trying to "rubbish anything Airbus".

And that is where I think those who wear their hearts on their sleeves are letting that distract them from a more critical reading. Airbus afficienados should not feel the need to blast the numbers because they favor the 772LR by a good percentage and Boeing afficienados should not embrace those numbers as "gospel truth" valid on every mission from 86nm to 8600nm. We use these numbers both because they are all that we have and because these planes are designed for 8000+nm segments. Even if an A345 proved more efficient then a 772LR at 2000nm, nobody is going to buy either plane for a mission that short.

Quote:
I was more interested in what we see in our everyday professional lives, to take all things into perspective.

But this entire thread is about the 772LR and the A345. And more specifically, how each compare to each other on identical mission segments. So comparing the 772ER and the A343 really isn't relevant to this thread, even if I do find it interesting information to know as an aviation enthusiast.
 
PolymerPlane
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 8:27 am

Quoting Pihero (Reply 81):
1/-PAR-JNB with a 30T traffic load :
Distance 4845 Nm, planned alternate GBE at 193 Nm.
772ER :
OEW :150.3 ; ZFW : 180.3 ; FOB 76.1 ; Burn off : 67.2 ;sector time :10.02

343 :
OEW :136.8 ; ZFW : 166.8 ; FOB 79.5 ; Burn off : 70.6 ; sector time :10.12

Well first of all, A343 vs. 772ER is a different story compared to 772LR and A345. Second of all, if you notice, 772ER is actually about 13 tons heavier OEW compared to A343 according to your number, and 23tons according to manufacturer's number. Yet, the two engined 772ER is still 5% more efficient than four engined A343.

According to manufacturer, A345 OEW is about 23 tons heavier than 772LR. So, I am not trying to argue your numbers. I respect you providing the real life numbers between the 772ER and A343, but this numbers cannot simply be extrapolated to the A345 vs 772LR comparison.

Maybe 10% is a reasonable number for the shorter route, but on longer route, this number might grow even wider since 772LR need to carry less fuel than A345. Remember that these planes are designed to do long haul. For medium haul route, I think NW has shown that A333 is much more efficient than 772(ER?)

Cheers,
PP
One day there will be 100% polymer plane
 
widebodyphotog
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 9:08 am

Quoting Pihero (Reply 81):

Good info and my I ask if you used AF flight planning data whose name begins with "G"? From the airplane OEW's it looks like you are using AF ship weights. I'm very familiar with their operation and procedures. However the A340-500 compared to the A340-300 is like comparing apples to grapes. It's an order of magnitude different in terms of weights, power, requirements and capabilities. For instance that 178t ZFW for your A343 example is 3t less than the empty weight of a generic A340-500HGW (and less than some in service ships). The cruise thrust requirements for A340-500 at an equivalent percentage initial cruise weight are 50% greater. It's a whole different animal and there is absolutely no comparison, other than the A345 and A343 have a common cokpit and rating...

For some fun may I suggest that you pull out some 777-300ER trips vs 747-400 and pay particular attention to the fuel burn vs total payload. Very interesting...

Also remember that the AF ship you used was at derated MTOW of 269.3. IIRC they currently running ships with 292t MTOW with de-rate from 297.6. Your de-rated TOW does skew the results a bit via second segment climb but since I don't know what the de-rate is on climb I can't tell you how much. What was your ICA for the TOW limited max payload example? And I'll tell you that I see 294t MTOW 777-200ER run with 40-43t payloads on a regular basis and being limited to lower altitudes for the start of cruise is not really a huge deal. Like everything it's a tradeoff and I'll trade a couple of grand in fuel burn for $10 or $15K in additional revenue any day of the week.

When evaluating 777-200LR weights are a bit higher but climb gradients are waaaay better below 690Klb. 777-200LR makes the 777-200ER look like a pig below certain weights. Above them things equal out a bit but you're still able to zip along at normal cruise speeds at very high cruise weights with big payloads, even with ICA limited to as low as FL280...to my mind that's the whole point of the thing.



-widebodyphotog
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keesje
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 6:02 pm

Quoting Pihero (Reply 83):
Why only offer one set of data that stretches the design of one airplane so that it looks awful ?

Although I very much appreciate the additions of WBP I have had many discussions with him regarding the data used (seatcounts/CASM). It is very well possible to select specific "industry / "brochure" numbers / conditions & create scenarios / flight profiles to make one aircraft look good over the other. Airbus & Boeing do it all the time. The press quotes the numbers below the line only..
"Never mistake motion for action." Ernest Hemingway
 
Pihero
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 9:15 pm

Quoting Widebodyphotog (Reply 86):
Good info and my I ask if you used AF flight planning data whose name begins with "G"? From the airplane OEW's it looks like you are using AF ship weights.

No comment, for obvious reasons.

Quoting Widebodyphotog (Reply 86):
Your de-rated TOW does skew the results a bit via second segment climb but since I don't know what the de-rate is on climb I can't tell you how much

No. The derate is on the structural MTOW. The TOWs I quoted are performance, they reflect the absolute capability of the plane in question in terms of performance, either 2nd segment or wheel speed. Had we had a brake energy limitation, I would have taken it into consideration and mentioned it.

Quoting Widebodyphotog (Reply 86):
For some fun may I suggest that you pull out some 777-300ER trips vs 747-400 and pay particular attention to the fuel burn vs total payload. Very interesting...

I did, a few years ago and I know that the 773ER is an absolute beast in terms of economics, be it for load capability -especially containers- or for b/o.

Quoting Widebodyphotog (Reply 86):
I see 294t MTOW 777-200ER run with 40-43t payloads on a regular basis and being limited to lower altitudes for the start of cruise is not really a huge deal. Like everything it's a tradeoff and I'll trade a couple of grand in fuel burn for $10 or $15K in additional revenue any day of the week

Again, I agree with you. But not out of JNB at ISA+15°c. On the max payload example above (example 3.A ),the initial alt capability (ICA) of the 777 is FL 330, not bad compared to the 343 which would start its cruise at FL 270.
On the tradeoff subject, one has also to consider the hefty taxes the airlines pay on some airports...the reason for the derated MTOW (enough said...).
I'd really like a comparison between the 345 and the 772LR on comparable sectors : for instance a LHR Santiago in Chile and a JNB-LHR..Unfortunately, I do not know anybody, except you, who could come back with the results.
Anyway, thanks for responding to my post. After all these years, I'm still learning.

Cheers.
Contrail designer
 
Pihero
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RE: A345 And 772LR Fuel Burn.

Fri Sep 22, 2006 9:24 pm

Stitch, PolymerPlanes and Keesje,
Sorry I was involved in responding to Widebodyphotog and forgot to mention your posts.
I think we quite agree on the values of published data.
Thanks for reading me.

Cheers.
Contrail designer
 
widebodyphotog
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RE: A345 And 772LR Fuel Burn.

Sat Sep 23, 2006 3:01 am

Quoting Pihero (Reply 88):
Again, I agree with you. But not out of JNB at ISA+15°c. On the max payload example above (example 3.A ),the initial alt capability (ICA) of the 777 is FL 330, not bad compared to the 343 which would start its cruise at FL 270.
On the tradeoff subject, one has also to consider the hefty taxes the airlines pay on some airports...the reason for the derated MTOW (enough said...).
I'd really like a comparison between the 345 and the 772LR on comparable sectors : for instance a LHR Santiago in Chile and a JNB-LHR..Unfortunately, I do not know anybody, except you, who could come back with the results.
Anyway, thanks for responding to my post. After all these years, I'm still learning.

Ah, I neglected to note the conditions ex JNB. However I have to say that the airport conditions departing airports like JNB and other hot and high airports are the exception and not the rule. Among comparable specific aircraft of course quads have an advantage over twins in certian hot and high aerodromes, but to use your example to make performance applicable in a general sense is quite unfair.

With that said the 777-200LR with GE-115B is a hot and high star performer. Out of JNB for example TOW would be limited to 700Klb at ISA +20C and 715Klb ISA +15C. This may seem like a large reduction in TOW from 766Klb certificated MTOW but for a distance of 4,800nm you can load the airplane to MZFW with lots of headroom underneath those limits when mission fuel is added. In fact for that distance TOW would need only be about 640Klb to make JNB-CDG under those conditioins. MZFW would give you an ACL of 58-64t depending on aircraft configuration and the burn looks to be about 2.5t more than your 777-200LR example.

For an A340-500, same conditions out of JNB, would need a TOW of 318-325t depending on weight variant, have an ACL of 54-56t and burn off fuel of 82-83.5t.

Field conditions are not a restriction for this rather extreme example for MZFW airplanes.

Out of SCL to LHR 777-200LR would have structural MTOW available until ISA +18 or so. However for a nominal distance of say 6,300nm to LHR it would never be necessary to use that high a TOW even at MZFW. An A340-500 using highest payload would be much closer to structural MTOW and still be carrying notably less payload than the 777-200LR.

The numbers:

777-200LR at 710Klb and (the lightest weight variant) A340-500 at 788Klb wth payloads of 64t and 56.5t repectively. BOF of 101.2t and 118.9t repectively and sector times of 13:17 and 13:32.

This is greatly simplified quick and dirty stuff but I think the differences can be appreciated by the example. Generic OEW is used for the airplanes, sorry for the mixing of units...



-widebodyphotog
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Pihero
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RE: A345 And 772LR Fuel Burn.

Sat Sep 23, 2006 3:56 am

That's good enough for me. Thanks.
These figures you quote on a SCL-LHR trip are a lot more valid to me than a bare max performance / manufacturer published claim. After all, I'm just an operator.
As for me being a bit unfair, regarding hot and high conditions, these are not as rare as one would think : Mexico, Johannesburg, Tananarive, Quito are some of the airports we deal with on a daily basis.
Lastly,somehow your figures explain why the 345/346 are not on our fleet, and I didn't have an access to the study. Thanks again.
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greasespot
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RE: A345 And 772LR Fuel Burn.

Sat Sep 23, 2006 5:45 am

Quoting Stitch (Reply 1):
So an A345 will burn roughly 20% more fuel in this mission and will arrive 20 mins after the 772LR.

Ok in an industry that stops flying blankets to save fuel do mods costing millions to save 3 and 4 % do you really think that anyone would use a 345 if it burned 20% more fuel?

GS
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Stitch
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RE: A345 And 772LR Fuel Burn.

Sat Sep 23, 2006 6:08 am

Quoting Greasespot (Reply 92):
Ok in an industry that stops flying blankets to save fuel do mods costing millions to save 3 and 4 % do you really think that anyone would use a 345 if it burned 20% more fuel?

Unlikely, which is why the A345's sales have been declining while the 772LR's sales have been increasing. For even when the fuel burn delta is not as extreme as that one case, the 772LR's fuel burn is lower and mission payload is higher then an A345's on the missions both planes are most likely to be used on.

However, fuel burn alone is not the only determiner of a plane's worth to an airline, especially when more efficient products are on the horizon. You may save 10% more fuel and carry 10% more payload with a 772LR then an A345, but if you're already marginal on the A345 (as SQ is), that extra monies coming in and not going out may not cover the monies spent selling the A345s and buying the 772LRs before something even better (787LR/A359R) becomes available and saves 10% more fuel and carries 10% more payload then the 772LR. Or even if it does, you may get upside down again with the 772LR when you try and replace it with the 787LR/A359R and you have to wait another decade to get back into the black. Better to just wait, soldier on with the A345 or just drop the routes, and then go with the 787LR/A359 and reap the benefits from Day One.

So that is why the 772LR is not replacing every A345 in service. For some carriers, they need the range or the payload or both. The 772LR is the logical choice at this time, so that is the plane winning the orders - even with existing A345 customers. But if you can wait, then many airlines (SQ, TG, etc.) feel that it's better to keep the A345 and wait for the next-generation LR from each supplier.
 
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Starlionblue
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RE: A345 And 772LR Fuel Burn.

Sat Sep 23, 2006 12:12 pm

Quoting Stitch (Reply 93):
So that is why the 772LR is not replacing every A345 in service. For some carriers, they need the range or the payload or both. The 772LR is the logical choice at this time, so that is the plane winning the orders - even with existing A345 customers. But if you can wait, then many airlines (SQ, TG, etc.) feel that it's better to keep the A345 and wait for the next-generation LR from each supplier.

Agreed, but the decision also depends on:
- Price of engines and lease rates. Those GE-90s ain't cheap.
- Price of aircraft and lease rates. Them 777-200LRs cost a bunch of money. Not that actual prices are common knowledge, but I'd be willing to bet the 345 is cheaper.
- Price and availability of pilot training.
- Price and availability of maintenance.
- Commonality with other aircraft in fleet for maintenance.
- Commonality with other aircraft in fleet for flight crew training.
- Commonality with other engine types in fleet.
- If you really need 4 engines to avoid ETOPS restrictions (unlikely at this point).
- Subsidies available (in theory).
- Political considerations from outright embargo to various trade agreements.
- Probably other stuff I have forgotten.

Many combinations of these factors could easily offset a 4-6% fuel burn advantage difference over 10 years. I'm not saying that's the way it is (sales seem to say otherwise) but fuel burn and existing inventory are not the only factors in play.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
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Stitch
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RE: A345 And 772LR Fuel Burn.

Sat Sep 23, 2006 12:59 pm

Quoting Starlionblue (Reply 94):
Many combinations of these factors could easily offset a 4-6% fuel burn advantage difference over 10 years. I'm not saying that's the way it is (sales seem to say otherwise) but fuel burn and existing inventory are not the only factors in play.

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elvis777
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RE: A345 And 772LR Fuel Burn.

Sun Sep 24, 2006 6:05 am

Howdy all,

WBP sure did provide an education ,at least for me! Anywasy, just to add my uniformed two cents and more questions....

Quoting Starlionblue (Reply 94):
Agreed, but the decision also depends on:
- Price of engines and lease rates. Those GE-90s ain't cheap.

I thought that the engines were basically free. And that the engine manufacturers made all their money on service and parts contracts??

Quoting Starlionblue (Reply 94):

- Price of aircraft and lease rates. Them 777-200LRs cost a bunch of money. Not that actual prices are common knowledge, but I'd be willing to bet the 345 is cheaper.

Did someone say earlier that the prices are comparable?? Is the 345 that much cheaper??

Quoting Starlionblue (Reply 94):

- Price and availability of pilot training.

On the grand scheme of things is this really a big ticke item that differs that much from bird to bird?? In other words does it cost much more to train a 777 driver than a 345 driver?? also LR and HGW birds are normally (Am I wrong on this?) NOT given to green captains. THese long routes are given to senior captains and crews. So are the costs that much different??
[/quote]

Quoting Starlionblue (Reply 94):

- Price and availability of maintenance.

Once again, similar question as before:is there a big difference in this, other than it costs more to service 4 engines as opposed to 2? Does it cost more to maintain a 777 than a 45?

Quoting Starlionblue (Reply 94):

- Commonality with other aircraft in fleet for maintenance.

From widebodys post I am infering that there is little in commonality betweena 345 and a 343 and much less with a 330. Am I worng on this? Is the commonality there so taht you can take a harness for a flap motor for a 343 and put it into 345? How about a 330 into a345? Is teh commonality argument a bogus point (other than driver training)? How do these costs offset teh larger flight costs of the 345??



Quoting Starlionblue (Reply 94):

- Commonality with other aircraft in fleet for flight crew training.

Yes, I think this is true to some extent. But same as before, these crews are ususually top of the line crews, experienced and with lots of seniority. What does a 320 or 330 have to do with this? in other words one would not usually put a 320 driver into a 345, even if he is trained. Ami Incorrect in thinking this?

Quoting Starlionblue (Reply 94):

- Commonality with other engine types in fleet.

Is this true? Does an engine in a 330 or 343 help me out when I own a 345? Are they that similar?

Quoting Starlionblue (Reply 94):

- If you really need 4 engines to avoid ETOPS restrictions (unlikely at this point).

I dont think this is a valid

Quoting Starlionblue (Reply 94):

- Subsidies available (in theory).

Is this legal??

Quoting Starlionblue (Reply 94):

- Political considerations from outright embargo to various trade agreements.

These things do exist in my opinion..



Peace

Elvis777

[Edited 2006-09-23 23:26:45]
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widebodyphotog
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RE: A345 And 772LR Fuel Burn.

Sun Sep 24, 2006 10:13 am

I've commented on the maintenance commonality subject before NG A340 to OG A340...SQ and others were particularly dissapointed to find that maintanence suppliers are vastly different between the two fleets offering almost zero commonality in that regard. For SQ Maintaining their small fleet has been particulary onerous given their high utilization. So one would have thought with their fairly substantial 777-300ER order they would have snapped up the -200LR without any qualms...

As far as engine maintenance goes, if 4 Trent engines have actually cost less to maintain than a pair of GE90's with nearly equal combined thrust, you could knock me over with a feather. Out of a fleet or a maintenance system it's hard to pull raw numbers specific to individual engines so actual numbers are a bit hard to come by. However, I'll say this in terms of how airlines have faired in operating the two shipsets. There have been now at least seven unscheduled engine removals for the Trent 500 while the GE90-11X has endured none...



-widebodyphotog
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Johnny
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RE: A345 And 772LR Fuel Burn.

Sun Sep 24, 2006 10:34 am

There is one thing i would like to mention:

Both A345 and B777LR are loosers in terms of sales.There are no other actual produced longrange airplanes which share such bad sales numbers.

They both have lost a lot of sales because their performance is not required on most routes for most of the airlines.

They did not change the business to a higher percentage of point-to-point flights.
A346 and B777-300ER are better solutions as their performance was better than promised. The future of comercial aviation are still the bigger birds with lower CASM which operate from Hub to Hub.
 
elvis777
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RE: A345 And 772LR Fuel Burn.

Sun Sep 24, 2006 11:15 am

Hi Johny,

You may be right. But maybe not. It is possible that the 777lr will continue to garner sales. Since it is a derivative class bird it may alrady be at break even point, taking into account cargo versions. So I am not sure that I woudl agree and put the LR into the loser category. It may also bring out other benefits to Boeing if it continues to sell more of these, even in marginal numbers...But I am just speculating on this.

Also your comment that a hub to hub , bigger birds, world is the way of the future is still not decided. I mean we are in the middle of figuring this out. So as not to hijack the thread, it seems as if off handedly you are giving a lot of credit to a yet unproven and very big whale like bird. It may be that it turns out to be a commercial failue- although perhaps not. But that is still undecided dont you think?

Furthermore your contention that a point to point system is less desirable than a hub to hub system based on the perceived failures of the 777LR or 345 to meet certain long range requirements. There are lots of other point to point routes. So much so that I think that The future of comercial aviation are still the smaller birds with lower CASM which operate from point to point.

Since we obviously dont see eye to eye we will jsut have to amicably disagree and see what the next few years will bring..

Now back to our scheduled program: the 345 vs. 77LR.

So as I suspected commonality argument with the eads series is a bit bogus, at least in the maintenance/parts dept. But to throw a bone to the eads guys, I imagine that the same can be said for the boeing series. That is that 37/57/67/77 birds dont share much in this area as well.

Anyways, so how about my question that a 320 driver will be given the keys to a 345 frame. I find that highly unlikely. Does it ever happen? That is probably not fair since one is a heavy and one is not. So how about a 330 driver ever getting the keys to a 340 series bird? Why would an airline ever want to do this? I mean even if the guy/girl is fully trained on both wont the scheduling/adminstrative stuff for doing this give people head aches?

Lets put the shoe on the other guy. Suppose that the 787 and 777 have only a class difference for pilot certification. If I got a pilot doing dfw-hawaii why would I want to pluck him out of the sky, if you would, and say today you will fly a 777 from dfw to beijing. Make sure you dont crash.

See what I am trying to get at?

Also, suppose that one says ok., I dont wat to put a 330 into a 340 seat. But I want to be able to train him rather quickly, to go to the right seat of the 340, so I dont spend that much money. That may indeed be true but how much time does it take to fully certify a well trained 767 FO or captain to transition to a 777? Or make it simpler how many hours / classes does it take a 737 guy to go to a md80 (I picked this since they are very dissimilar planes with very different handling characteristics.

You can see where I am going with this cnat you? I want to open up the commonality argument and see if it indeed soes hold any water.

Peace

Elvis777
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Stitch
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RE: A345 And 772LR Fuel Burn.

Sun Sep 24, 2006 11:26 am

Quoting Johnny (Reply 101):
Both A345 and B777LR are loosers in terms of sales.There are no other actual produced longrange airplanes which share such bad sales numbers.

Actually there is: the A340-8000 with a grand total of one.  Smile

But seriously, I do understand your point. These birds are designed for very specific roles, though the 772LR does have the advantage that it improves on the 772ERs payload when the mission profiles are greater then 2000nm. Anyone know how the A345 does vis-a-vis the A343 out to the latter's max range?

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