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Old 12th Aug 2008, 07:57   #1 (permalink)
 
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A380 vs. B777-300ER

Just a quick first comparison, not overly precise but close. Same dest., same day.

A380
6400 ESAD, 13h17', payload 66t (max), pax 489, trip 178300, appr. cargo 20t, could take add. 8.8t of fuel, max ZFW.
- appr. 2.7kg fuel per kg payload, 364 kg fuel per pax.

B777-300ER
6370 ESAD, 13h17', payload 49t, pax 360, trip 112700, appr. 15t cargo, ZFW restricted (60t max)
- appr. 2.3kg fuel per kg payload, 315 kg fuel per pax.

I stand to be corrected, but otherwise .... no comment.
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Old 12th Aug 2008, 08:59   #2 (permalink)
 
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you asked for it so I will correct you !

the max payload of the A380 is NOT 66t

the comparison is a false one as comparing a 777-300 at 360 seats and an A380 at 489 seats is not comparing apples with apples

the A380 is carrying many more 'premium' passengers than the 777-300. If you were to configure the 2 a/c with similar cabins the A380 would be carrying around 600 Pax

the A380 is carrying lots of additional weight compared to the 777-300 - showers, bars, etc. This all costs fuel burn, but the airline clearly thinks it's worth it. The A380 is probably carrying additional reserve fuel so early in it's operational life;
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Old 12th Aug 2008, 09:24   #3 (permalink)
 
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- DOW 299t vs. MZW 366 is 67 tons payload, (big difference, sorry).
- Both aircraft are 3 class configured in similar proportions, meaning naturally that there are more high yield pax on the AB, but again: proportionally.
- no additional fuel on both flights.

The A380 might carry more luxury deadload and it might even be worth it. But AB propagated it beeing the most environementally friendly bird - looking at the burn vs. kg or pax in it's current versions on SQ or EK it seems simply not.
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Old 12th Aug 2008, 18:41   #4 (permalink)
 
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Sorry, but MEW is quoted by Airbus as 276t (typical empty weight) - that gives a Max payload of 90t. Of course in service the real OEW depends heavily on the airline and the weight they choose to carry for luxury items like showers, bars, etc.

The EK & SQ 777-300's and A380's might both be 3 class, but they are far from being equivalent. The A380 has nearly twice the cabin floor area than a 777-300, so I maintain that IF configured in similar layouts the A380 would carry nearly 600 Pax.

If you redo the calculations for the A380 with 600 Pax you will see that it's much more efficient than the 777 - the size effect.

All this is negelecting the fact that the A380 is designed to acheive more than just minimum fuel burn - Noise for example. It is way ahead of the 777-300 in both external and internal noise (yes I have travelled on both). Some of these additional objectives compromise slightly the fuel burn.

So environmenally friendliness is about more than just fuel burn and ultimately it's up to the airlines how they use the A380 - not Airbus. Today they are clearly using it to offer more rather than carry more pax with less fuel.
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Old 12th Aug 2008, 21:09   #5 (permalink)
 
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But, if you only get 350pax? What then?
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Old 13th Aug 2008, 00:23   #6 (permalink)
 
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Er......A350?
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Old 13th Aug 2008, 02:59   #7 (permalink)
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My answer is more radical. I have seen a few A380 economic analyses which back me up. I think the A380 is more fuel efficient in most of its applications. How come? The A380 goes onto routes which are too big for one B777 and too thin for two B777. So if your required pax uplift is somewhere between 360 and 489, you are running one A380 against two B777. Ignoring cargo for simplicity, and doing the fuel use sums for 425 pax:

A380 178300 / 425 = 420 kg/pax, compared to:

2 x B777 = 2 * 112700 / 425 = 530 kg/pax

IMHO the A380 is a finely tuned machine which works economically in only a very limited spectrum of operations. Inside that spectrum, it works well. Outside that spectrum, it doesn’t. One doesn’t directly match the A380 head to head with a B777 – it is outside the spectrum of successful A380 ops.

The A380 aircraft is being taken up by airlines with the route planning sophistication to be able to match the A380 to a specific need and deploy their other aircraft (including B777) to complement it.
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Old 13th Aug 2008, 03:18   #8 (permalink)
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So all what AB has to do now is to make the 350 better than the 777 and that's it about big airplanes ?

530 Kg per pax at about $1,000/mt makes $530, multiply by 2.5, an average of $1,250 for that long trip ticket, actually there are tickets sold for less I believe.
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Old 13th Aug 2008, 09:33   #9 (permalink)
 
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Take a look at the SQ 777-300ER's - which are configured like the A380 - with the same business class seats (42 vs 60 on the A380) and are operated on similar long haul routes (SIN - FRA & CDG).

They seat ONLY 278 Pax NOT 360.

So redo the fuel burn comparison with 278 seats vs 471 and you will see a different story.

This like for like comparision shows that the A380 carries 70% more pax than the 777-300ER. So in fact it makes sense for routes that don't support 2 full 777-300's, but with the better economics it still makes sense even of you only fill the A380 to an 85% load factor - the equivalent of 2 777-300's. Even with 85% load factor - 405 Pax the fuel burn per seat numbers are similar to the 777's.

And of course on high density routes where airlines are slot limited (like at LHR) it carries 70% more pax for the same number of slots - this is what is was designed for and what most of the customers have ordered it for. It's no coincidence that LHR expects to see more A380's than any other airport.
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Old 15th Aug 2008, 11:18   #10 (permalink)
 
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This is comparing apples with pears again.
Don't take into consideration 2 other aircraft when comparing your favorite. This can never match. It is simply a matter of kgs payload vs. burn. That is what "environemental friendly" is all about. The pax demand is about commercial economics.
By the way: EK 777-300ER has 42 business seats.

The moment i will see a A380 flightplan which demonstrates LESS kgs fuel used vs. kgs transported, i will start accepting it as a progress in aviation.
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Old 15th Aug 2008, 11:33   #11 (permalink)
 
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Sorry, but it's you that is comparing apples and pears !!

The EK B777-300's do have 42 'business' class seats - but they are 7 abreast 'business class'. In the REAL SQ business class they are 4 abreast - like on the A380 - the same seats in fact.

The EK B777-300's have cattle class seating in economy - 10 abreast !!

Sure if you configure the a/c like this you can get 360 seats in it. If you configure the A380 in the same way - 6 abreast business and 11 abreast in economy you will easily get 600 seats in it. And it WILL burn less fuel per pax than the B777-300.

FACT
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Old 15th Aug 2008, 14:58   #12 (permalink)
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Thanks pool and engineer07. Even though you're both PPRuNe members that joined only this year, you have been able to contribute some very interesting insights into the A380 and 777. pool- indeed you’ve obviously got an airline economics interest, and engineer07 has a clear and very useful appreciation of the numbers that really count. The debate between the two aircraft will continue.

In the meantime, we enjoy TechLog as a rather more measured forum than some of the others. More tech than prune??.
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Old 15th Aug 2008, 15:27   #13 (permalink)
 
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Sorry, but it's you that is comparing apples and pears !!

The EK B777-300's do have 42 'business' class seats - but they are 7 abreast 'business class'. In the REAL SQ business class they are 4 abreast - like on the A380 - the same seats in fact.

The EK B777-300's have cattle class seating in economy - 10 abreast !!

Sure if you configure the a/c like this you can get 360 seats in it. If you configure the A380 in the same way - 6 abreast business and 11 abreast in economy you will easily get 600 seats in it. And it WILL burn less fuel per pax than the B777-300.

FACT


Slam dunk...can't argue with that! Well said!
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Old 16th Aug 2008, 04:27   #14 (permalink)
 
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Let me rephrase that:It's about kgs of PAYLOAD (kgs) vs. fuel burn and basically the number of passengers, seat configuration, shower or bar has little to do with this.On a purely company economical note, certainly the one has more comfort arguments than the other, it just depends on how you configure the cabin, no doubt you could eventually configure the 777 to look better in that respect.On a environemental note, there is no question that the only value that counts is burn vs. kgs transported.I say it again: The moment i see a actual flightplan that shows the A380 burn less fuel per kilo transported, i will start to value it as what AB propagates -> as a step forward concerning environemental protection progress.
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Old 16th Aug 2008, 08:36   #15 (permalink)
 
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POOL - aircraft manufacturers claim many facts about their products, some of which, such as dry operating weight and fuel-burn are never achieved. In evaluating the product, the airline will look at operating costs and profit. Environmental performance will be a distant consideration. Using your own example, 3 A380s will carry as many passengers and more freight (pure profit) than 4 B777-300s. That makes more sense to a "bean-counter".
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Old 16th Aug 2008, 08:54   #16 (permalink)
 
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Lies, damn lies and statistics

Why not compare the original 777 with the original 380 and see what that does?
When the 380 has been stretched, then compare it with the 777-300ER
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Old 16th Aug 2008, 10:18   #17 (permalink)
 
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Payload

Pool,You are absolutely right - it's about PAYLOAD. An a/c manufacturer builds the airframe and the airline decides what to carry in it. Everything they decide to carry in it is PAYLOAD - be it Pax, Freight, Showers, Bars, Comfy Seats, etc.In the case of the A380 ALL the airline customers to date have decided to carry a lot of weight (payload) to provide luxury. They could decide (and may do so in the future) to bin the luxury and configure the a/c like EK's B777-300. The TOW and Fuel Burn will be almost unchanged (all those seats, showers, bars add up to a lot of Pax believe me), but the Fuel per seat numbers will be transformed.As also noted in this tread the economics of a streched A380-900 (the a/c is already designed for such a stretch) will be another step change - if/when Airbus can afford/be persuaded to launch such an a/c. B777-300 vs A380-900 will be no contest - but we should expect that - there is the size and technology difference playing in the A380's favour.
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Old 16th Aug 2008, 11:34   #18 (permalink)
 
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Seats, showers etc. are not PAYLOAD.

Pay Load is only stuff that "Pays" i.e Pax and Freight

15/08/08
A380 DXB-JFK Full Pax. Fuel=198T
flight time=13rs 25mins

16/08/08
77W DXB-JFK Full pax Fuel= 120T
ft= 13hrs 6 mins

1. Different days so slightly different winds and routes..(Freight unknown)
2. Wasn't the 380 supposed to fly at .85 mn
3. A380 is using KBOS as altn, while 77W using KEWR. Can 380 land at KEWR???
4. A380 great if you can get 400+ pax but on a day you have 250 then that fuel bill looks rather large.
5. 78T extra to carry 130 more pax!!!!!
6. Ek have done their homework and are sure it's worth it.
7. It's great for staff travel. Might even get on.
8. Eco friendly. Don't think so. More Eco .... maybe.
9. Does the 380 carry any freight or is it full of Bags??
10. Everybody says it looks ugly... well the 787 and 350 don't look much better either. Modern aerodynamics.
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Old 17th Aug 2008, 11:36   #19 (permalink)
 
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Payload

Technically you are right that seats, showers, etc are not usually considered as payload. But as you say Payload is what 'Pays'. The reason why pax choose to fly on the A380 (and belive me they do !) and to pay higher prices (which they also do) is beacause they have comfy seats/suites and other ameneties like showers. So these items do generate revenue - that's why EK have them in the aircraft - and hence if you want to compare different a/c you have to consider this as Payload.You are absolutely right that flying an A380 with 250 Pax on board does not work economically. I would be very interested to know what the load factors on the EK A380's and B777-300's are like (especially in business class) ? SQ's experience so far nearly 1 year into Ops is that the A380 load factors (especially in business) are better than the B747/B777's on the same routes.
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Old 17th Aug 2008, 12:31   #20 (permalink)
 
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Why compare the 380 with the 777? Why not with the 747?
The 380 is made for a specific niche, and I think it may be better on that than the 777, but the 'niche' of the 777 is much bigger ,and it doesn't necessary coincide ,even partially with that of the 380.
. Both planes are designed for a particular type of routes ,and may be the best on their sector.
As the 737 may be more appropriate than the 777 on some paticular flights or area of operation.Or any other example.
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