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NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 1:35 pm

Sorry Zeke - but your faith in the A340 seems even more misplaced on a thread which started with reports that airlines are 'trading' their A380 compensation rights to free them up from unwanted A340 orders. Presumably so they will be left free to order Triple Sevens instead?

Quoting Shenzhen (Thread starter):
to transform these penalties into cancellations of orders which they have on other models of the Airbus family, and in particular of A340-500/600.
 
Dougloid
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 1:53 pm

Quoting Zeke (Reply 47):
The excess thrust means inefficient cruise, as the thrust is not optimum for the cruise level, means the aircraft is burning additional fuel. It is also carrying around additional engine weight and drag for that excess thrust, which also increase fuel burn again.

I'm not entirely sure that I agree with this proposition...you could just roll off a little power if you had a mind to....
 
Shenzhen
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 4:17 pm

Funny how Airlines working with Airbus about A380 delay compensation has turned into Boeing Strike and ANZ 777 deliveries.

I agree with UDO, probably Emirates trying to get out of some of their A340 comimitments (if the ariticle is even factually correct).

Cheers.
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 4:22 pm

Quoting Iwok (Reply 48):
Are you saying that two engines add more weight and drag compared to four engines?

Yes..

A340 - CFM56 - wt 4860 lb x 4 = 19440 lb
B777 - GE90 - wt 16644 lb x 2 = 33288 lb

2xGE90 have 71% more mass than 4xCFM 56


CFM56 - diameter 1.830 m length 2.510 m
GE90 - diameter 3.404 m length 5.181 m

Frontal area

CFM56 - 2.63 m^2 x 4 = 10.52 m^2
GE90 - 9.1 m^2 x2 = 18.20 ^2

2xGE90 have 73% more frontal area than 4xCFM 56

Considering them as wetted areas on cylinders to simplify calculations

CFM56 - 2.63 m^2 + (1.830 x 2.510) = 7.223519909 m^2 x 4 = 28.89 m^2
GE90 - 9.1 m^2 + (3.404 x 5.181) = 26.737 m^2 x 2 = 53.47 m^2

2xGE90 have 85% more wetted area than 4xCFM 56

Quoting Iwok (Reply 48):
How are you defining efficiency?

The major driving factor for all airlines at the moment is fuel burn. I have been comparing the A340-300 to the 777-200.

I don’t have no data for the 777-300ER and 777-200LR, Boeing have claimed they have changed design from earlier 777's by 35 percent.

Quoting Iwok (Reply 48):
Do you drive at full throttle all the time?

No, nobody does. However every little bit of additional mass the aircraft has, be it in additional fuel, additional hardware requires more lift to be generated. More lift, more drag, higher fuel burn.

Quoting OldAeroGuy (Reply 49):
why the 773ER has a 28.5 tonne lower MTOW (351.5 vs 380) and a 10% lower fuel capacity than the A346.

My FCOM 3 for the A340-600 has a MTOW of 375000kg and 141500 l / 111078 kg of fuel. Can you provide us with the FCOM values for the 773ER ?

Quoting NAV20 (Reply 50):
Sorry Zeke - but your faith in the A340 seems even more misplaced on a thread which started with reports that airlines are 'trading' their A380 compensation rights to free them up from unwanted A340 orders.

The A380 provides for lower cost per seat mile than the 777 and 340, also additional passengers can be carried for same slot time.

Unlike the A340 the 7773ER has similar limitations as the A380 with respect to airports it can serve. To my knowledge it has the highest PCN/ACN of any passenger aircraft currently in service.

Quoting Dougloid (Reply 51):
I'm not entirely sure that I agree with this proposition...you could just roll off a little power if you had a mind to....

Its inefficient from the point of view you are carrying around additional mass, 2 x GE90s are 13848 lb heavier than 4xCFM56's. Instead of a fixed engine if you were to carry 13848lb of additional fuel on your plan, you would have to carry additional fuel for that fuel. Our flight plans have that adjustment if we want to leave with more fuel on top of what the computer spits out. The cost of carrying that 13848 lb of engine weight would be in the order of 600 t - 1000 t of fuel a year.

Not to mention the additional fuel required to be carried by twin engine aircraft for DP1 and DPD considerations on every long range flight plan for ETOPS requirements.
 
astuteman
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 4:49 pm

Quoting AirFrnt (Reply 46):
That's a weak link at best. From what I understand, there are contract clauses to protect boeing (if Boeing's workers strike) or the airlines (if a aircraft is due to be delivered during a strike).

That's true, AirFrnt, but they won't protect Boeing from loss of revenue/earnings.
 
QFA001
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 5:02 pm

Zeke, your data is great, but I'm afraid it's a moot argument. Udo was not referring to the A340-300 vs B777-200ER as you have, but the A340-600 vs B777-300ER. The characteristics of the latter two airplanes do not reflect the former two...

Quoting Zeke (Reply 53):
2xGE90 have 71% more mass than 4xCFM 56

... However, two -115Bs have less mass than four Trent 556s.

Quoting Zeke (Reply 53):
Frontal area

Again, four T500s has more frontal area than two GE90s.

Quoting Zeke (Reply 53):
The cost of carrying that 13848 lb of engine weight would be in the order of 600 t - 1000 t of fuel a year.

It would be if the SFC of the different engine types were the same. However, they are not. The GE90 has lower SFC than CFM56-5.

 airplane QFA001
 
iwok
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 5:39 pm

Zeke, using the 340-300 for your comparison starts you in a weak position. The 343 has hair dryers for engines, which helps the drag and wetted are case a bit. Going to more modern planes such as the 346 vs. 773-ER and the case for twins is even stronger.

Quoting Zeke (Reply 53):
Yes..

A340 - CFM56 - wt 4860 lb x 4 = 19440 lb
B777 - GE90 - wt 16644 lb x 2 = 33288 lb

2xGE90 have 71% more mass than 4xCFM 56


CFM56 - diameter 1.830 m length 2.510 m
GE90 - diameter 3.404 m length 5.181 m

No:
The CFM56-5C has a dry weight of about 8800lb
CFM

A340-300 - CFM56-5C - wt 8800lb * 4 = 35,200 lb
B777-200 -GE90-77B - wt 16600lb * 2 = 33,200 lb

If you run the numbers for the 777-300ER and the 340-600 you will see similar results. Less is not more..

Quoting Zeke (Reply 53):
The major driving factor for all airlines at the moment is fuel burn. I have been comparing the A340-300 to the 777-200.

Fuel burn alone is not the driving factor. Its fuel burn to transport x-passengers and y-pounds of cargo.

Quoting Zeke (Reply 53):
Considering them as wetted areas on cylinders to simplify calculations

CFM56 - 2.63 m^2 + (1.830 x 2.510) = 7.223519909 m^2 x 4 = 28.89 m^2
GE90 - 9.1 m^2 + (3.404 x 5.181) = 26.737 m^2 x 2 = 53.47 m^2

2xGE90 have 85% more wetted area than 4xCFM 56

OK, so the GE90's have higher wetted area which will contribute to the overall frictional losses of the aircraft. However, the wetted area of the engines pales in comparision to the fuselage and wing.

We also need to include drag on the engines (frontal area.)

Comparing the drag on 4 vs 2 engines

D=1/2 R V^2 A Cd

to compare both a/c we could check just the fan diameters as the reference area..
777-200 : 9.1m^2*2 = 18.2
340-300: 2.63m^2*4 = 10.52

Therefore, the drag of 2 GE90-77B's is 73% greater than 4 CFM56-5C's.

Now, lets take a look at the 773-ER vs. 346
773-ER : GE90-115B - 18,000lb * 2 = 36,000 lb
346 : Trent 556 - 10,500lb * 4 = 42,000 lb

GE90-115B: Dia=3.43m : Area=9.24m2
Trent 556: Dia=2.46m : Area=4.75m2

Comparing drag:
773-ER: 9.24m^2 * 2 = 18.48
346: 4.75m^2 * 4 = 19

For the 346 and 773ER, the drag is about the same. Wieght clearly favors the twin.

No wonder the 340 replacement is going to be a twin  scratchchin 

iwok
 
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garpd
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 6:12 pm

Quoting Udo (Reply 36):

The key term is "early customers". Anyways, that article is four and a half years old. Great source for today...

Does that make it any less viable?

I've seen some people use other fairly old links to fight their cause and not seen you blink an eye.
 
glacote
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 6:50 pm

Quoting NAV20 (Reply 35):
Glacote, I have literally lost count of the number of times I have posted this link, in response to the same query. The story confirms both the large initial discounts offered and the penalty-free cancellation clause up to 12 months before delivery.

Thank you. I feel extremely frustrated that it still lacks asource: "has learnt" is extremely vague - especially when IIRC the only source for the "40% discount" at that time was Baseler. I still suspect them to have only this source.

Which does not mean that the figure is incorrect. But it is widely incompatible with the 7 billions USD figure for EK deal.

So who is right? Baseler?

I take your point but I would appreciate another source on the free 12-month cancel option. This is something terrific.
 
Udo
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 7:43 pm

Quoting AirFrnt (Reply 46):
Funny, almost all of the orders were four and a half years ago. Unless you have personal information that indicates that the contracts where changed?

Sorry to correct you, but it's just not true that "almost all of the orders" were placed in 2001.

Quoting Zeke (Reply 47):
. The fuel burn of the A340 is lower than a 767, and lower than a 777.



Quoting Zeke (Reply 47):
The 777 is not much more than a scaled up 767.

You better shouldn't believe to much Airbus PR...  Wink

Quoting GARPD (Reply 57):

Does that make it any less viable?

No, but the article is not representative for all orders placed later (after mid-2001). Some people seem to forget that.


Regards
Udo
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 10:05 pm

Quoting Glacote (Reply 58):
I feel extremely frustrated that it still lacks asource:

Fair enough, Glacote. Deepest sympathy with your frustration - but I'm buggered if I'll hunt around for yet more links. Believe it or don't believe it, it's a free country last I heard..... Smile

Quoting Glacote (Reply 58):
But it is widely incompatible with the 7 billions USD figure for EK deal.

How 'wildly incompatible'? They've ordered 41 passenger and two freight versions, presumably with deliveries spread over a number of years, and some allowance therefore made for inflation. $US7B. divided by 43 is $US163M. each.

Quoting Udo (Reply 59):
it's just not true that "almost all of the orders" were placed in 2001

Perfectly correct, Udo, as far as it goes. According to this, no less than 118 of them (say about 80% of the current total?) were placed a lot earlier than that. In 2000, in fact.  Smile

"With orders and options from nine world-renowned customers (Air France, Emirates (the first customer), Federal Express (the cargo model launch customer), International Lease Finance Corporation, Lufthansa, Qantas, Qatar Airways, Singapore Airlines, and Virgin Atlantic), the Airbus A380 was officially launched on December 19, 2000."

http://www.aircraft-info.net/aircraft/jet_aircraft/airbus/A380/
 
leelaw
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Joined: Sat May 29, 2004 4:13 pm

RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 10:13 pm

Quoting Udo (Reply 59):
Quoting AirFrnt (Reply 46):
Funny, almost all of the orders were four and a half years ago. Unless you have personal information that indicates that the contracts where changed?

Sorry to correct you, but it's just not true that "almost all of the orders" were placed in 2001.

O.K....perhaps the better question is how much of the current order backlog was sold at "launch" (heavily discounted) prices?

BTW, your lack of reply to this remark is conspicuous by its absence:

Quoting NAV20 (Reply 44):
Do you seriously think that a prospective purchaser in the second half of 2001 (or any time in 2002 for that matter) would have read (and filed) those figures in 'Business Week' and then cheerfully agreed to pay an extra hundred million bucks or so per frame........?
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 10:29 pm

Crossed with yours, Leelaw. I suppose I should give up on providing facts that Airbus fans could readily have found out for themselves.

But Udo's earlier forthright comments on the Triple Seven's superiority leads me to believe that he can occasionally be convinced of something. So, to paraphrase one of my 'heroes', 'I purpose to argue it out on this line if it takes all summer.'  Smile
 
Udo
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 10:51 pm

Quoting NAV20 (Reply 60):
Perfectly correct, Udo, as far as it goes. According to this, no less than 118 of them (say about 80% of the current total?) were placed a lot earlier than that. In 2000, in fact.

At least 90 orders were placed in late 2001 or after 2001. Check the links:

http://www.ameinfo.com/42943.html

http://www.aviationweek.com/shownews/01paris4/topsto02.htm

http://www.bizjournals.com/wichita/stories/2004/08/23/daily42.html

http://edition.cnn.com/2003/WORLD/eu...pe/06/19/paris.airshow.superjumbo/

http://money.cnn.com/2001/12/06/international/lufthansa/

http://www.prdomain.com/companies/f/...00207july/pr_fedex_nr_20020716.htm

http://www.ups.com/content/ca/en/about/news/01_10_2005.html

Quoting Leelaw (Reply 61):

O.K....perhaps the better question is how much of the current order backlog was sold at "launch" (heavily discounted) prices?

Yes, good question. And who knows the answer?

Quoting Leelaw (Reply 61):
BTW, your lack of reply to this remark is conspicuous by its absence:



Quoting NAV20 (Reply 44):
Do you seriously think that a prospective purchaser in the second half of 2001 (or any time in 2002 for that matter) would have read (and filed) those figures in 'Business Week' and then cheerfully agreed to pay an extra hundred million bucks or so per frame........?

An extra hundred million per frame - funny.

And whatever articles report - Airbus could deny it or find whatever excuse. Remember all the reports about the jetBlue and easyjet deals...do you think every A320 customer after the B6 & U2 deals was offered the same discounts? Guess...

Quoting NAV20 (Reply 44):
It's the naivete' of yer av'rage Airbus fan that never ceases to amaze me, Udo.

I could say the same about some of your odd theories (500-seats etc.) which are purely based on speculations.
Oh btw, just because I'm confident about the A380 project doesn't turn me into an Airbus fan...

Quoting NAV20 (Reply 62):
Crossed with yours, Leelaw. I suppose I should give up on providing facts that Airbus fans could readily have found out for themselves.

If it only were always facts...

Quoting NAV20 (Reply 62):
But Udo's earlier forthright comments on the Triple Seven's superiority leads me to believe that he can occasionally be convinced of something.

If it's the truth and proven by reliable sources, yes, I can be convinced.


Regards
Udo
 
Thorben
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 10:58 pm

Quoting Udo (Reply 63):
If it's the truth and proven by reliable sources, yes, I can be convinced.

But you didn't answer my question about the payloads. As far as I know the A346 carries more passengers over a longer range than the 773ER. So it can be heavier, I suppose.
 
OldAeroGuy
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 11:37 pm

Quoting Zeke (Reply 53):
My FCOM 3 for the A340-600 has a MTOW of 375000kg and 141500 l / 111078 kg of fuel. Can you provide us with the FCOM values for the 773ER ?

Where you getting your numbers?

For the A346, the Airbus website says:

MTOW: 380 tonne
Fuel Volume: 204,500 l

http://www.airbus.com/en/aircraftfam...0a340/a340-600/specifications.html

For the 773ER from the Boeing website:

MTOW: 351.5 tonne
Fuel Volume: 181,280 l

http://www.boeing.com/commercial/777family/777technical.html

These are the two models that have about the same P/L and are the basis for my earlier statements. The A346 fuel volume is in fact 12.8 % higher, not 10% as I stated earlier (age does things to the memory).

None of the data above supports your supposition that a twin is heavier and has a higher fuel burn than a corresponding quad.
 
OldAeroGuy
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Sun Sep 18, 2005 11:44 pm

Quoting Thorben (Reply 64):
But you didn't answer my question about the payloads. As far as I know the A346 carries more passengers over a longer range than the 773ER. So it can be heavier, I suppose.

If that's true, then the sales figures will be a good clue.

At present, the 772LR/773ER seem to have a bit of a lead over the A345/A346. Since everyone knows the Boeing product is more expensive, there must be some other reason it's selling.
 
leelaw
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 12:01 am

Quoting Udo (Reply 63):
Quoting Leelaw (Reply 61):

O.K....perhaps the better question is how much of the current order backlog was sold at "launch" (heavily discounted) prices?

Yes, good question. And who knows the answer?

You seem to have implied in your replies that you had some inkling:

Quoting Udo (Reply 42):
The article refers to early customers - and that's it. It's not representative for all customers following later (after first half of 2001).



Quoting Udo (Reply 59):
Quoting GARPD (Reply 57):

Does that make it any less viable?

No, but the article is not representative for all orders placed later (after mid-2001). Some people seem to forget that.



Quoting Udo (Reply 63):
Quoting NAV20 (Reply 60):
Perfectly correct, Udo, as far as it goes. According to this, no less than 118 of them (say about 80% of the current total?) were placed a lot earlier than that. In 2000, in fact.

At least 90 orders were placed in late 2001 or after 2001.
 
Danny
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 12:19 am

Quoting Udo (Reply 1):
Why not take the chance and get rid of some orders for mostly obsolete aircraft? They

A340-600 obsolete?  sarcastic  There are airlines still flying DC-9s.
 
Udo
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 12:38 am

Quoting Leelaw (Reply 67):
You seem to have implied in your replies that you had some inkling:

No, just like all of us I have no clue about what's in the specific contracts. I simply tried to make clear that an article from mid-2001 is not necessarily representative for all orders placed later.

Quoting Danny (Reply 68):
A340-600 obsolete?

Please read my comment again. I said the A346 is mostly obsolete for Emirates.


Regards
Udo
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 12:56 am

Udo, trying to move things on, let's step back and look at the whole picture a bit.

As far as the A380 is concerned, Airbus is facing a loss of at least $50M. per airframe for at least the first two years of production - almost certainly considerably more because of compensation issues. That will take their loss on the project well above the $15 billion or so they have already 'blown' on development. And even the later orders, given the low launch-price 'datum' they started from, can't be at much more than cost price, if that.

To hang on to those (loss-making) orders they appear to be having to agree to cancel firm orders on smaller aircraft, on which they would presumably have made a profit. Beyond that, you appear to agree that they can't hope for much more in the way of orders for the 'obsolete' A340, due to competition from the 777. And one must expect that the 787 is making similar inroads into the market for the A330.

That leaves the A320 - which is holding its own against the 737, but only JUST holding its own. They certainly can't afford to jack A320 prices up to the point where they can hope for 'supra-normal' profits without losing out to Boeing on that model as well.

I don't know what business you're in yourself - but surely, if it was in anything like the 'losing' condition outlined above, you'd be pretty worried?
 
Thorben
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 2:13 am

To my knowledge A346 and 773ER orders are about the same (115 to 114), but the A345 against the 772LR is 26 to around 20.

Concerning my performance analysis:

A345 against 773ER

Airbus has:

4% more payload
3.5% more range
with 7.7% more fuel

A345 against 772LR

Airbus again 4% more payload
with 6% more fuel
with the Boeing having 2.3% more range.

What was that claim once that the Boeing's had a 18-25% better fuel burn?? Great story!


Quoting OldAeroGuy (Reply 66):
If that's true, then the sales figures will be a good clue.

At present, the 772LR/773ER seem to have a bit of a lead over the A345/A346. Since everyone knows the Boeing product is more expensive, there must be some other reason it's selling.

Certainly other reasons than the economics. Things like fleet commonality, corporate interest (why do the Japanese buy 767, 777, and 787?) or whatever play a role as well.
 
B2707SST
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 3:15 am

Quoting Thorben (Reply 71):
Airbus has:

4% more payload
3.5% more range
with 7.7% more fuel

A345 against 772LR

Airbus again 4% more payload
with 6% more fuel
with the Boeing having 2.3% more range.

What was that claim once that the Boeing's had a 18-25% better fuel burn?? Great story!

I don't know what numbers you are using, but the payload-range curves published by Boeing and Airbus tell a different story.

Using a hypothetical 100,000 pound payload, Airbus gives the A345HGW (which has not been ordered yet) a still-air range of 8,200nm at MTOW. This variant has a MTOW of 837,800 lbs. and an OEW of 385,400 lbs. Subtracting OEW and payload from MTOW gives fuel on board of 352,400 lbs.

http://www.airbus.com/en/aircraftfam...a330a340/a340-500/performance.html
http://www.airbus.com/en/aircraftfam...0a340/a340-500/specifications.html

For the same 100,000-pound payload, the 777-200LR has a still-air range of 8,890 nm at MTOW. Boeing shows the 772LR's MTOW at 766,800 lbs. and its OEW at 320,000 lbs., so fuel on board for this mission would be 346,800 lbs. The 777 flies the same payload nearly 700 nm more than the A340 and still does it with less fuel on board.

Alternatively, the 772LR can match the A345's 8,200 nm range at a takeoff weight of about 735,000 lbs., implying fuel on board of about 315,000 lbs., 11% less than the A345's for the same payload-range.

http://www.boeing.com/assocproducts/aircompat/acaps/777rsec3.pdf, page 4
http://www.boeing.com/assocproducts/aircompat/acaps/777rsec2.pdf, page 3

--B2707SST
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 5:01 am

Quoting Iwok (Reply 56):
No:
The CFM56-5C has a dry weight of about 8800lb

To compare apples with apples (ie with the same configuration, accessories attached etc) according to GEAE (not the web site)
GE90-115B Weight (dry) 19,000 lb
RR Trent 556 Weight (dry) 10,400 lb
CFM56-5C Weight (dry) 5,830 lb

The weight I had previously used for the CFM56 engine was unknowingly without accessories.

Quoting Iwok (Reply 56):
Now, lets take a look at the 773-ER vs. 346
773-ER : GE90-115B - 18,000lb * 2 = 36,000 lb
346 : Trent 556 - 10,500lb * 4 = 42,000 lb

GE90-115B: Dia=3.43m : Area=9.24m2
Trent 556: Dia=2.46m : Area=4.75m2

Comparing drag:
773-ER: 9.24m^2 * 2 = 18.48
346: 4.75m^2 * 4 = 19

The GE90-115 is 140" in diameter fitted or 3.556 m giving a frontal area of 9.931 m^2, and 19,000 lb.

The Trent 556 is 97.4" in diameter fitted or 2.47396 m giving a frontal area of 4.807 m^2, and 10,400 lb.

So comparing the 777-300ER and the A340-600, the 773ER has more drag, and total engine weight is 3600 lb lighter than a A340-600.

Quoting QFA001 (Reply 55):
Again, four T500s has more frontal area than two GE90s

Incorrect - see above

Quoting OldAeroGuy (Reply 65):
Where you getting your numbers?

For the A346, the Airbus website says:

MTOW: 380 tonne
Fuel Volume: 204,500 l

My A340-600 FCOM 1.28.10 P 4 revision 1 and "Maximum takeoff weight (brake release)... 368 000 kg* (811 293 lb)" from 3.01.20 P 4 revision 10.

I try and not use web site data, as manufacturers will make assumptions like an IGW landing gear installed, or additional optional this or that. Taking that data as fact you are then saying its true as it on a web site. The numbers I have given are from FCOMs, not web sites.

I still stand by my statements that a quad is more efficient for long range, and ultra long range than a twin, however they are not as good for short to medium haul.

The majority of the worlds long and ultra long haul civil and military transport is not accomplished with twins.
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 5:12 am

Quoting B2707SST (Reply 72):
I don't know what numbers you are using, but the payload-range curves published by Boeing and Airbus tell a different story.

I have been using numbers from my A340-300/600 FCOM (i.e. flight manuals 4 volumes). I also have access to some 320/737/330/747/767/777 manuals.

Both manufactures are guilty of publishing data on their web sites which is somewhat short of realistic. It contains data which has a whole list of favorable assumptions which you and I are not privy to.

As far as day to day operations, a 5% change in CG location can increase fuel burn by 20t over a flight.
 
Dougloid
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 5:49 am

Quoting Zeke (Reply 74):
As far as day to day operations, a 5% change in CG location can increase fuel burn by 20t over a flight.

Great point about CG management vs fuel burn....absolutely on point....part of the reason the MD11 had a wet stabilizer.
 
dalecary
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 6:55 am

Zeke,

your numbers may be dazzling but the stark reality is that the A345/6 is not selling and the 772LR/773ER is. Please list all new 345/346 orders this year and compare to all 772LR/773ER orders this year. I think the airlines may know something you don't know about the efficiencies of operating a twin over a quad. Let's not even talk about such points as MTOW comparisons b/w the 773ER and 346.
 
OldAeroGuy
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 7:08 am

Quoting Zeke (Reply 74):
I have been using numbers from my A340-300/600 FCOM (i.e. flight manuals 4 volumes). I also have access to some 320/737/330/747/767/777 manuals.

Both manufactures are guilty of publishing data on their web sites which is somewhat short of realistic. It contains data which has a whole list of favorable assumptions which you and I are not privy to.

I agree with what you are saying in part. However, MTOW and Fuel Volume data are not unrealistic since airlines purchase these values, unlike the website quoted seat counts.

I'm curious where you got a FCOM for an A346HGW, since none have been certified or delivered yet.
 
QFA001
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 7:30 am

Quoting Udo (Reply 69):
No, just like all of us I have no clue about what's in the specific contracts.

I am aware of A.net users who have seen one or more of the contracts. I happen to be one of them. So, I hope you reconsider your claim.

Quoting Zeke (Reply 73):
The GE90-115 is 140" in diameter fitted or 3.556 m giving a frontal area of 9.931 m^2, and 19,000 lb.

The Trent 556 is 97.4" in diameter fitted or 2.47396 m giving a frontal area of 4.807 m^2, and 10,400 lb.

You should check the validity of your data before posting. (But you're not alone, a lot of people should do that.)

The Trent 556 has a fan diameter of 97.4-in. The GE90-115B has a fan diameter of 128-in. What you did was to incorrectly apply a "fitted" value (ie. including the nacelle) for the GE90 but not the T500.

Once you have corrected your error you will note that...

Quoting Zeke (Reply 73):
So comparing the 777-300ER and the A340-600, the 773ER has more drag, and total engine weight is 3600 lb lighter than a A340-600.

...this is an incorrect assertion.

Anyhow, Dale is right: the B777LR is overpowering the A340NG in the marketplace. The growing reality is that the days of the A340 are numbered.

 airplane QFA001
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 1:18 pm

Quoting QFA001 (Reply 78):
You should check the validity of your data before posting. (But you're not alone, a lot of people should do that.)

I did contact GEAE for the data I had, where did you get your data from ?

Quoting QFA001 (Reply 78):
...this is an incorrect assertion.

Please can you back your statement up ?

Quoting QFA001 (Reply 78):
Anyhow, Dale is right: the B777LR is overpowering the A340NG in the marketplace. The growing reality is that the days of the A340 are numbered.

I don't know any airline flying the 777 on ultra long haul routes at the moment. Please advise me which are. Quads are not dead, the A340, A380, 747 are here to stay. As you would know Qantas purchased 4x747-400's over the 777.

Quoting OldAeroGuy (Reply 77):
I'm curious where you got a FCOM for an A346HGW, since none have been certified or delivered yet.

Its the current CX A340-300/600 FCOM, in service at the moment.

Quoting OldAeroGuy (Reply 77):
I agree with what you are saying in part. However, MTOW and Fuel Volume data are not unrealistic since airlines purchase these values, unlike the website quoted seat counts.

Yes however you are insisting on comparing an aircraft certified to carry 550 passengers (777-300ER) to and aircraft certified to carry 440 passengers (A340-600). Some even try and compare the A340-600 range payload to the 747-400 (certified max 660 passengers). Is the 777-300ER really 25% (550/440) better than the A340-600...No ..... Is the 747-400 really 50% (660/440) better than the A340-600...No

I still stand by my comments that the quad A340-600 is more efficient than a 777-300ER. The A340-600 is a closer match to the 777-200ER (max certified passengers 440). If you compare range payload between the two they are more closely matched, with the A340-600 uplifting more payload and range over the 777-200ER.

People also insist on comparing the A340-500 (certified max 375 passengers) to the 777-200LR (certified max 440 passengers), is the 777-200LR really 17% (440/375) better than the A340-500 ... No

At the end of the day an airline will chose an airframe that has the right passenger and cargo capacity for their network. They don't look at a website look at the range payload of the highest and longest range aircraft, and then try and build a network.

In terms of ultra long haul, operators are charging a premium for those seats, the cabin has generous leg room for the 16-18 hour sectors. I only know of ultra long haul being done in A340-500 aircraft at present.
 
dalecary
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 1:34 pm

Quoting Zeke (Reply 79):
I don't know any airline flying the 777 on ultra long haul routes at the moment. Please advise me which are. Quads are not dead, the A340, A380, 747 are here to stay. As you would know Qantas purchased 4x747-400's over the 777.

Huh!!! Maybe that's because the 772LR isn't yet in service with airlines. QF purchased 6x 774ER and not 4 and who says that was instead of 777s??? Could have been a capacity issue. Anyway, that was 5 years ago and this is today. How will you react when SQ dumps it's A345ULH fleet in favour of 772LRs....because it's gonna happen.
Quads the size of the A340 are almost dead. Quads the size of the 747/380 aren't ,because engines aren't big enough to allow twins of this size.
You failed to answer my direct question; how many airlines have ordered A345/346 this year, compared to 772LR/773ER orders? Maybe you would like to contact Airbus and ask why the promised A345/6 dispatch reliability rate hasn't yet reached the promised figures after 12 months EIS, and we are now 3+ years after EIS???
 
Udo
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 3:18 pm

Quoting QFA001 (Reply 78):
I am aware of A.net users who have seen one or more of the contracts. I happen to be one of them. So, I hope you reconsider your claim.

There are always exceptions to a major rule.  Wink


Regards
Udo
 
iwok
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 3:22 pm

Quoting Zeke (Reply 73):
CFM56-5C Weight (dry) 5,830 lb

Check the link again, and you will see the CFM claims that is weighs 8,796lb dry. I think they might know what they are talking about, but that is mere speculation.  scratchchin 

Quoting Zeke (Reply 73):
The weight I had previously used for the CFM56 engine was unknowingly without accessories.

Sounds to me like what you were doing is hand-waving.

Quoting Zeke (Reply 73):
I still stand by my statements that a quad is more efficient for long range, and ultra long range than a twin, however they are not as good for short to medium haul.

What makes a 4-holer more efficient than twins for LR and ULR, and less efficienct for short to medium haul?

Your main points in the 2 vs 4-holer discussion appear to be:
1) 2-holers have heavier engines
2) 2-holers have more engine drag
3) 2-holers have higher fuel burn.

If what you are saying is true, why ever fly a twin?

Quoting Zeke (Reply 73):
The majority of the worlds long and ultra long haul civil and military transport is not accomplished with twins.

Please define short to medium, long haul and ultra long haul.

Quoting Zeke (Reply 47):
It is also carrying around additional engine weight and drag for that excess thrust, which also increase fuel burn again.

Again, proven wrong, not matter how fast and hard you wave your arms.  Smile

Quoting Zeke (Reply 73):
I try and not use web site data

Sounds to me like you don't like to use any realistic data at all.  Wink


-iwok
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 3:25 pm

Quoting Dalecary (Reply 80):
How will you react when SQ dumps it's A345ULH fleet in favour of 772LRs....because it's gonna happen.

I would think its a logical fleet planning stratergy considering the size of their existing 777 fleet. Savings will be with crewing and maintenance, not direct operating. The A345 fleet is a micro fleet at SQ, and getting smaller after one of the went AOG after a heavy landing.

Quoting Dalecary (Reply 80):
You failed to answer my direct question; how many airlines have ordered A345/346 this year, compared to 772LR/773ER orders?

I am a professional pilot, I will leave the aircraft order stats, and who/what lands where to the professional spotters.

Quoting Dalecary (Reply 80):
Maybe you would like to contact Airbus and ask why the promised A345/6 dispatch reliability rate hasn't yet reached the promised figures after 12 months EIS, and we are now 3+ years after EIS???

Your source for this ? Not the case at CX, SQ, LH, VS, SA. Flight international ran an article on this not so long back, it was not the case as you suggested.

It is not the case at CX and we have a 340/777/747 fleet, including 346.

I will freely admit any new aircraft entering service is not perfect its not just a A345/346 issue, or an airbus issue, or a Boeing issue ... Your balanced comments are welcome.

United 777s, heavy but happy
13 Sep 1995

Boeing tackles tail-wag problems on United 777s
6 Dec 1995

Kiss-seal tear fores BA to ground 777s
7 Feb 1996

United attacks 777 reliability
13 Mar 1996

Compressor damage gounds 2 of BA's 777s
5 Feb 1997

Oscillations force BA 777 back to Heathrow
19 Feb 1997

BA suspends 777IGW ETOPS operations
19 Mar 1997

777 suffers new engine troubles
22 Oct 1997

UK AAIB study GE90 after aborted 777 takeoff
18 Mar 1998

GE90 inspections continue after 777 Heathrow surprise
4 April 1998

FAA issue airworthiness directive for 777-200 tail corrosion
10 Feb 1999

Boeing tackles 777 power problems
18 Aug 1999

Urgent GE90 removal starts on worldwide 777-200 fleet
11 Jan 2000
 
Ruscoe
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 3:34 pm

Zeke,
There is a fundamental difference between the problems Airbus has with the 345&6 and the problems Boeing has (had) with the 777 series.

The 340 series problems are a reflection of the basic design philosophy of having 4 engines. This cannot be easily changed, except by creating a new aircraft, the 350.

The problems with the 777 are technical and can and will be solved.
Ruscoe
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 3:49 pm

In any case, this thread isn't (wasn't?) about the relative merits of the A340 v. the 777.

If you want interminably to discuss that subject, Zeke, why not start your own thread on it?
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 4:09 pm

Quoting Iwok (Reply 82):
Check the link again, and you will see the CFM claims that is weighs 8,796lb dry.

I checked with the parent of CFM, GEAE, the 5,830 lb is what they gave me.

Quoting Iwok (Reply 82):
Sounds to me like what you were doing is hand-waving.

No some engine accessories are customer options. When I look at out FCOMs we have 12 pages of customer options, each customer option just being a mod number on a single line.

Quoting Iwok (Reply 82):
What makes a 4-holer more efficient than twins for LR and ULR, and less efficienct for short to medium haul?

Many of the same arguments as to why a 738 or 747 with winglets is used on longer haul flights, and without on short haul. Short to medium haul you don't spend as much time in the cruise, and turn arounds are quicker.

Twins have higher initial cruise altitudes, quicker to altitude than a quad, however once in cruise are less efficient. Similar to a 738 with winglets, over a 1 hour sector, the winglets could actually reduce payload and would have very little difference to fuel burn and flight time. However over a 5 hour sector the reduced fuel burns from the decreased drag become significant.

Quoting Iwok (Reply 82):
If what you are saying is true, why ever fly a twin?

Airlines like SQ will one day use a 777 for 4 return SIN-KL flights and then the next might go to MEL. For its route structure the 777 is better, but is limiting on the SIN-MAN route where they need a tech stop. They use quads mainly for the long haul direct flights to LHR.

Quoting Iwok (Reply 82):
Please define short to medium, long haul and ultra long haul.

Thinking of the aircraft types ..

Short - up to 5 hr sectors - F100, 737, A320
Medium - up to 12 hr sectors - 757, 767, A330, 777
Long - up to 14 hr sectors - 767, 330, 747, 340, 777
Ultra long - up to 20 hr sectors. 772LR, 345

From a flight crew point of view, anything above medium haul will have relief crew and crew rest areas.

Quoting Iwok (Reply 82):
Sounds to me like you don't like to use any realistic data at all.

Yes its very easy to sit on the fence and take quick swips at people, however none of your posts seem to have much substance, or for that matter a well constructed argument.

I have taken the time to explain myself as best I can, referring to real data from real aircraft manuals, or from real engine manufactures representatives.

It is obvious to me and I guess other readers that you are not professionally involved in long haul flying in a quad or twin and fail to appreciate the real day to day issues involved in that type of operation. It is also obvious that you have not flown a boeing or airbus product as a professional flight crew.

If you have done so, you would not ask such elementary questions, and would understand aspects of long range flying like CG management, flex tracks, step climbs, and diverting 1000+ nm for better winds, and the differance between short and long haul flying.

If real world flying was all over land, with good airports everywhere, no terrain, no cargo or baggage, no catering, no passengers, no winds, no destination weather, no IFE, constant atmosphere regardless of latitude then referring to a simplistic manufacturers sites for a range payload comparisons would be valid.
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 4:19 pm

Quoting NAV20 (Reply 85):
In any case, this thread isn't (wasn't?) about the relative merits of the A340 v. the 777.

My apologies, I have only been rebutting previous comments. I have not been trying to hijack the thread.

The thread was about A380 Delays Cost A340-5/-6 Orders, which soon turned out to be a discussion on 777 orders and how they are the "Boeing wonder aircraft" and better for all types of missions.

I have tried to put some balance back rebutting some of the claims made having real 747/A330/A343/A346 experience.
 
astuteman
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 4:43 pm

Quoting Zeke (Reply 86):
It is also obvious that you have not flown a boeing or airbus product as a professional flight crew.

Wow, passionate response, Zeke! What types do you fly?
A
 
iwok
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 5:12 pm

Right off the CFM website.


CFM56-5C2
-5C3
-5C4


TAKEOFF CONDITIONS (sea level)


- Max. takeoff (lb)
31,200
32,500
34,000


- Airflow (lb/sec)
1,027
1,045
1,065


- Bypass ratio
6.6
6.5
6.4


IN-FLIGHT PERFORMANCE (installed)

(35,000 ft-Mach=0.80-ISA)



- Max. climb thrust (lb)
7,370
7,370
7,580


- Overall pressure ratio at max. climb
37.4
37.4
38.3


- Max. cruise thrust (lb)
6,910
6,910
7,100


ENGINE CHARACTERISTICS


- Length (in)
103
103
103


- Fan diameter (in)
72.3
72.3
72.3


- Basic dry weight (lb)
8,796
8,796
8,796


Quoting Zeke (Reply 86):
I checked with the parent of CFM, GEAE, the 5,830 lb is what they gave me.

What did Snecma say?

Quoting Zeke (Reply 86):
If you have done so, you would not ask such elementary questions, and would understand aspects of long range flying like CG management, flex tracks, step climbs, and diverting 1000+ nm for better winds, and the differance between short and long haul flying.

The reason for my "elementary questions" is that I am trying to get a feel for what you are talking about.

What does CG management and diversions for wind have to do with the 2-hole / 4-hole debate.

Just because you are a pilot, does'nt mean you can determine the most efficient aircraft design. That is left to the engineers.

Quoting Zeke (Reply 86):
Yes its very easy to sit on the fence and take quick swips at people, however none of your posts seem to have much substance, or for that matter a well constructed argument.

I am not taking quick swips, I am responding to your 4-holers are lighter and have less drag statements.

You're the one started this in the first place. You stated higher engine wieght and engine drag as the main culprits. I come back at you with solid examples of how the wieght and CdA is better for a twin, especially newer twins i.e 773ER, 346. You then deny the data is correct, claim to have spoken to the factory, read your FCOMs and typed-off what you believe is the correct info; all the while posting no link of any sort, and condemn my post for being un-substantiated.  Embarrassment

Quoting Zeke (Reply 86):
It is obvious to me and I guess other readers that you are not professionally involved in long haul flying in a quad or twin and fail to appreciate the real day to day issues involved in that type of operation. It is also obvious that you have not flown a boeing or airbus product as a professional flight crew.

Pretty obvious from my profile that I am not a pilot. Pretty obvious you are not an engineer.  Wink

BTW, claiming that 4-holers for LR based on day to day operations is a completely different discussion.. What I am saying is that your claims of higher weight and drag being the main culprits are unsubstantiated.

Quoting Zeke (Reply 86):
Many of the same arguments as to why a 738 or 747 with winglets is used on longer haul flights, and without on short haul. Short to medium haul you don't spend as much time in the cruise, and turn arounds are quicker.

This is simply a cost benefit analysis. Doing a lot of short jumps means less reduction in fuel usage which may make winglets not worth their cost in saved fuel. Even short hops with a wingletted plane will yield reduced fuel consumption, but their fuel savings may be less than the cost to install them.

The winglet arguement does not apply to your incorrect statement that 2-holers have heavier engines and higher drag than 4-holers. A heavier plane with higher drag would always be the worst case (fuel consumption wise) for both long and short haul.

iwok
 
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garpd
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 5:12 pm

Quoting Thorben (Reply 71):
To my knowledge A346 and 773ER orders are about the same (115 to 114), but the A345 against the 772LR is 26 to around 20.

Concerning my performance analysis:

A345 against 773ER

Airbus has:

4% more payload
3.5% more range
with 7.7% more fuel

A345 against 772LR

Airbus again 4% more payload
with 6% more fuel
with the Boeing having 2.3% more range.

What was that claim once that the Boeing's had a 18-25% better fuel burn?? Great story!

Thorben, your constant mis representation of facts and figures is quickly eroding any credibility you have.

The 773ER and A345 are not competitors and I beleive you "compared" them just to give the illusion Airbus are on top.
Your 772LR and A345 comparison is also flawed, as others have pointed out.

Why are you so desperate to show Airbus on top all the time? Do you have insecurities about them?
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 7:27 pm

Quoting Iwok (Reply 89):
Pretty obvious from my profile that I am not a pilot. Pretty obvious you are not an engineer.

Incorrect. I spent 7 years working as an aerospace engineer and have done structural design with composites for both airbus and boeing using CATIA. I have also worked on other projects for UK based companies. I still do takeoff performance and other consultantcy work on the side.

I have since been flying medium to long haul for about the same about of time.

Quoting Iwok (Reply 89):
What did Snecma say?

Didn't ask, I went to university with a GEAE manager. The data came from him. You don't think that possibility there is an error, as the CFM56-5B3 of 33k lb thrust engines are listed on the same site as about 5250 lb ? That's more thrust than the ones installed on our 343's.

A glaring example of how web site data need to be used with caution is that on the Snecma and GE sites the engine diameter for the GE90-115B are different. I believe both are listed without the accessories attached.

The accessories is an important consideration, due to the low pod height on the 737 the CFM56 installation on them has more drag than the A320 version.

Quoting Iwok (Reply 89):
A heavier plane with higher drag would always be the worst case (fuel consumption wise) for both long and short haul.

Incorrect. Forward CG at a lower weight can have a higher fuel burn than for a aft CG at a higher weight. Forward CG you also need increase fuel used on takeoff as takeoff thrust needs to be increased (FLEX change).

Quoting Iwok (Reply 89):
What I am saying is that your claims of higher weight and drag being the main culprits are unsubstantiated.

Well you better go out and rewrite all the aircraft deign and performance books. The A343 wing shares 96% structural commonality to the A333 wing however in cruise the A343 has a lower fuel burn than the A333.

At about 90% MTOW the 330 will go straight to FL380, whilst the 343 will only get FL330. It would take the A340 4 minutes longer to get to cruise altitude, however once there is has a lower fuel burn.

The reason for the faster climb and higher initial cruise altitude has to do with greater excess thrust on the twin. The twin has greater excess thrust to meet one engine out climb requirements on takeoff. That ability to generate excess thrust costs weight, frontal area, and wetted area, weight and drag costs fuel, nothing is free.

I would even go as far to say that if one engine out climb performance was not a consideration after takeoff, the 777-300ER could get away with two Trent 772 engines (71,100 lb class) rather than the GE90-115B's. If it did so it would have a lower fuel burn, and about 15000 lb lighter. In that case I would see the twin not being overpowered, and would be more efficient than a quad.

Quoting Iwok (Reply 89):
Even short hops with a wingletted plane will yield reduced fuel consumption, but their fuel savings may be less than the cost to install them.

I agree that winglets reduce the induced drag, however there is also and increase in drag from the higher surface area. Nothing is free.

The weight of the winglets also reduces the usable payload of the aircraft, and it costs fuel to carry the weight of them (generating more lift), and that additional fuel also leads to additional fuel, it a vicious circle. Over longer sectors the savings outweigh the costs.

P.S. thought the large font made your post look childish

[Edited 2005-09-19 12:31:21]
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 7:29 pm

Thanks Zeke - apologies in my turn for snapping!  Smile

As I said earlier, I think the significance of the subject story is that Airbus are apparently choosing to relinquish profitable orders so as hang on to unprofitable ones. On the face of it, that doesn't make any sort of business sense.

As to WHY the airlines want to relinquish their orders for A345s/6s, time will tell. Possibly they have decided that they don't have a requirement for extra longhaul capability at all. But the more likely explanation is that they would prefer to order 777s, or possibly 787s. I think the advent of the 772LR could have particularly big implications in this part of the world - it would allow an 'express' service direct to Heathrow, nonstop one way at least; and also direct services to DFW or O'Hare. No A340 variant can offer those options. We'll know a lot more in a month or two - both Qantas and Singapore have RFPs out which are clearly likley to result in orders for A340s, A350s, 787s, 777s, or a mixture of those types.

On which aeroplane is the better bet for a given airline, my own suspicion is that a point which scores with the bean-counters - if not the pilots - is that two engines probably translate into a lot less hangar-time (and spares stocking?) than four?

I notice from your list that you haven't apparently flown a 777 yet? Do you think you might change your mind when you try one? Incidentally, what is its reputation among pilots? Is she a bitch or a honey?  Smile
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 7:53 pm

Quoting NAV20 (Reply 92):
I notice from your list that you haven't apparently flown a 777 yet? Do you think you might change your mind when you try one? Incidentally, what is its reputation among pilots? Is she a bitch or a honey?

Most of the guys don't care what they fly as long as they get their allowances, time off, staff travel, and good routes. If you ask someone just starting, I am sure they will love it, ask someone with 10000 hours its just another glass airplane that you just spend endless hours in monitoring the autopilot with brief flashes of hand flying.

Guys at SQ like them over the 340 and 747 as their promotion system is partially based on number of sectors flown, the 747 and 340 fly long haul and not as many sectors a year, The 777 is used for regional and medium to long haul, I do hear they are looking of the 767/330 size, as the 777 is an overkill on some routes.

People do seem to like flying them, however I do get told its not like previous Boeings in climb performance, i,e, 757 and 767. They say at altitude they get a little to close to high speed buffet for their liking, and the wing loading makes turbulence not as comfortable as other types. Most people say they had more "fun" in a 737 than a 777.

Don't get me wrong, I don't dislike the 777, just from my point of view both are fairly closely matched, and going from international airport to another..Looking around you see a good mix everywhere.
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 9:01 pm

Interesting about the rate of climb, Zeke. I mostly flew gliders, so any kind of engine seems almost like 'cheating' to me! But on powered light aircraft I was always taught 'full throttle/fine pitch' all the way to height; and as far as I know the same sort of principle tends to apply to jets, from the belief that the faster you get up to the thin air at height, the less fuel you use.

I believe that the 787, with its high-aspect-ratio wing, won't have the rate of climb that commercial jets have had up to now. Come to that, I've heard that the A340's climb rate is nothing to write home about. Possibly 'cruise-climb' or 'step-climb' will be more the recommended method in the future, in the name of overall fuel economy.
 
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zeke
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 9:29 pm

Quoting NAV20 (Reply 94):
I've heard that the A340's climb rate is nothing to write home about.

Its not a 757, its not that bad...

A340 MTOW takeoff

height/time/dist from brakes release
1500 3/7
5000 5/15
10000 8/29
15000 11/59

B744 MTOW takeoff

height/time/dist from brakes release
1500 3/5
5000 4/16
10000 7/27
15000 10/50

Optimum climb for the 744 at MTOW is FL290/FL320 for the A340 at MTOW

A340 257t MTOW 27 min 149 NM to FL320
B744 394t MTOW 21 min 130 nm to FL290

A 737 will outclimb a 747 or 340 at MTOW any day.
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 10:02 pm

Interested in your priorities on climbout, Zeke - given that you're a professional pilot.

I only ever used an old-fashioned A/P without an auto-throttle. It would hold a course for you, and an altitude (actually a 'level') once you reached it. But you had to organise the speed and rate of climb yourself; basically you left full power on, and let the aircraft settle into a climb at the best achievable rate; if the speed looked like dropping off too much, you trimmed the nose down a bit.

You guys can set everything - power and/or airspeed and/or rate of climb. Which do you give priority to, speed over the ground or the rate of climb? From what you say, seems like you feel that the faster the thing goes up, the better - whether or not it's making much progress over the ground?

[Edited 2005-09-19 15:03:15]
 
airfrnt
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 10:58 pm

Quoting NAV20 (Reply 70):
As far as the A380 is concerned, Airbus is facing a loss of at least $50M. per airframe for at least the first two years of production - almost certainly considerably more because of compensation issues. That will take their loss on the project well above the $15 billion or so they have already 'blown' on development. And even the later orders, given the low launch-price 'datum' they started from, can't be at much more than cost price, if that.

I doubt that the numbers are actually really as bad as you are making them out here. I think a more realistic number is between 10-25 million for the first two years.

Quoting NAV20 (Reply 70):

To hang on to those (loss-making) orders they appear to be having to agree to cancel firm orders on smaller aircraft, on which they would presumably have made a profit. Beyond that, you appear to agree that they can't hope for much more in the way of orders for the 'obsolete' A340, due to competition from the 777. And one must expect that the 787 is making similar inroads into the market for the A330.

The A350/777 battle was getting settled before the 787 took flight. The A350 is competitive with the 787, although I suspect that like the 777 versus A340 it eventually will be clearly inferior to the 787 as a delivered production.

Quoting NAV20 (Reply 70):

That leaves the A320 - which is holding its own against the 737, but only JUST holding its own. They certainly can't afford to jack A320 prices up to the point where they can hope for 'supra-normal' profits without losing out to Boeing on that model as well.

You have to remember that scheduling plays a role in this. Airbus clearly is "forgiving" older orders to win new business, but the A320 has a decent backlog, and frankly I view the A320 versus 737NG as tied. As fuel continues to be a issue, I think this starts to tip towords the 737 but there are lots of circumstances to tip it back.

So even when Airbus does forgive orders for other planes to try and lure people to the A380, I don't think it will have a drastic effect on the other lines.

(It will have a effect however, which is yet another reason why I think the A380 was badly conceived).
 
NAV20
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Mon Sep 19, 2005 11:18 pm

I don't think we're disagreeing much, Airfrnt. I've given my calculations for the $US50M. per frame figure, and I still think that, given the appreciation of the Euro, it's an under-estimate of the likely figure. Anyway, even if the loss per frame turned out to be only $25M., the losses would only be 'less bad', as the Spanish say. Or 'down to crisis level', as we tend to say here  Smile

Couldn't agree with you more that the A380 was 'badly conceived'. And they seem to be making another mistake on a similar scale with the A350 - a hasty 'makeover' of the A330 that has very little chance of being competitive with the 787. And which, in any case, guarantees an even worse cash flow problem for the next five years or so, before they can hope to start delivering it.
 
PlaneDane
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RE: A&C - A380 Delays Cost A340-5/-6 Orders?

Tue Sep 20, 2005 12:26 am

Quoting Zeke (Reply 74):
I have been using numbers from my A340-300/600 FCOM (i.e. flight manuals 4 volumes). I also have access to some 320/737/330/747/767/777 manuals.

Both manufactures are guilty of publishing data on their web sites which is somewhat short of realistic. It contains data which has a whole list of favorable assumptions which you and I are not privy to.

But, Zeke, you're also claiming just the oppostie. Your position is that data published on Airbus' website is less favorable than what is found in your FCOM. I am struggling to think of any reason why this would be.

Shouldn't Airbus really be publishing the correct data you have? I think so. After all, what would Airbus' motivation be for presenting its products less favorably to the public?

You also said you worked at Boeing on the 777 program. I was there too for a little over 4 years. Where and when were you there? What did they have you working on?

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