aircanada014
Posts: 1224
Joined: Sun Oct 09, 2005 2:24 pm

Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 7:41 am

Hello all


I was wondering which of the two aircraft burns the fastest and most fuel the B747-400 or the A340-300? I know this hasn't been discussed before if so I'm sorry.
 
aa1818
Posts: 1515
Joined: Sat Feb 04, 2006 2:03 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 7:20 pm

Quoting AirCanada014 (Thread starter):
I was wondering which of the two aircraft burns the fastest and most fuel the B747-400 or the A340-300? I know this hasn't been discussed before if so I'm sorry.

I would imagine that the 744 does, simply because it is notably larger and thus heavier and is based on much older technology!!!

However, since the a/c are not in the same class you would have to look on a per seat mile basis- and although i have no sources or am not even 100% certain, i'd have to say that the 744 should have lower seat mile fuel burn!!!

Cheers!
AA1818
“The moment you doubt whether you can fly, you cease for ever to be able to do it.” J.M. Barrie (Peter Pan)
 
ehho
Posts: 769
Joined: Thu Dec 15, 2005 3:26 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 8:19 pm

Here's a rough, very rough CASM calculation:

The MTOW of the A343 is 260/275 tons (depending on model: normal or E). That of a B744 is anywhere between 360 and 412 tons (ER) depending on the engines.

Fuel capacity of the A343 is 141,500 liters (37,380 gallons). That of the B744 is 216,840 liters (57,285 gallons).

An A343 carries 303 pax in 3-class config, and 335 in 2-class. The B744 carries 416 pax in 3-class config, and anywhere between 500 and 568 in 2-class.

Now let's take an average route that could be served by both. Let's assume CDG-SFO, on which AF runs both types. The G-C distance is 8985km (5583mi, 4852nm). Let's assume for the sake of the argument that both pax and cargo capacity are used fully, so the planes fly MTOW, and let's assume (totally disregarding AF seating and engine choice) that both types fly 3-class. This is what you get per seat per km:

A343> 141500:303:8985=liters per seat km= 0.520
B744> 216840:416:8985=liters per seat km= 0.580

So, in this example, A343 is more economical. Of course, many other factors play paramount roles for airlines deciding on procurement of aircraft. What is the density of the proposed routes? What is the price for pax tickets? What is the cargo price? What's the cost of the aircaft? What is the length of the proposed routes? What is the altitude of the stations? What is the seating model? What are the fuel prices? etc. etc.

All these variables can give you an endless array of outcomes, favoring A343 and B744 equally I'm sure. For a more intersting, relasitic analysis, one should compare specific aircraft of a specific airline, on a specific route with specific load factors. Then it can be interesting to see whether e.g. for AF it makes more sense to send an A343 or B744 to SFO or for SQ to send one or the other to AMS. Maybe someone has such figures and could enlighten us.
"Get your facts first. Then you may distort them as much as you please" -- Mark Twain
 
Rj111
Posts: 3007
Joined: Wed Sep 08, 2004 9:02 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 9:20 pm

No offense, but that's a pretty shocking analysis EHHO. The A343 and 744 can't take their full load of fuel at max payload for starters. Theres no indication that CDG-SFO would use all the fuel and 303 seats for a 3 class A340 layout is very generous.

The 744 has been quoted as having the best CASM of an pax aircraft currently flying (i'm skeptical of that, but i'll go along with it) so it beats the A343 for efficiency. Then again LH have said in the past that their A343s are their most effcient jet, but i'm skepitcal about that too.

If you're lucky, WBP will turn up an give you an analysis.
 
trex8
Posts: 4576
Joined: Sat Nov 02, 2002 9:04 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 9:39 pm

I can't link it but in LH's annual report for 2000 they give actual fuel burn for the entire LH group fleet.
744 is 4.3liters per passenger per 100km
A343 is 4.0
 
PhilSquares
Posts: 3371
Joined: Sun Mar 28, 2004 6:06 pm

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 9:50 pm

Quoting RJ111 (Reply 3):
No offense, but that's a pretty shocking analysis EHHO. The A343 and 744 can't take their full load of fuel at max payload for starters.

I beg to differ. Speaking ONLY for the 744 you can take full tanks, 360 passengers and 7.2 tons of bags/cargo. That puts you right at MTOW. Most 400s are configured for between 340-360 passengers, so you'd have no problem taking a full boat and max fuel and all the bags.
Fly fast, live slow
 
Treg
Posts: 488
Joined: Tue Oct 16, 2001 8:55 pm

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sat Oct 28, 2006 9:51 pm

sasflightops.com gives the following figures:

SAS A340-300: 0.039 liters per seat per km
SAS A330-300: 0.035 liters per seat per km

Unfortunately they do not have any 747 in their fleet...
 
ehho
Posts: 769
Joined: Thu Dec 15, 2005 3:26 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-

Sat Oct 28, 2006 9:56 pm

Quoting RJ111 (Reply 3):
The A343 and 744 can't take their full load of fuel at max payload for starters. Theres no indication that CDG-SFO would use all the fuel and 303 seats for a 3 class A340 layout is very generous.

I know, I know, I was totally unscientific. However:

Quoting Trex8 (Reply 4):
744 is 4.3liters per passenger per 100km
A343 is 4.0

my finger-in-the-wind estimate turned out to be pretty neat!

[Edited 2006-10-28 14:57:28]
"Get your facts first. Then you may distort them as much as you please" -- Mark Twain
 
Rj111
Posts: 3007
Joined: Wed Sep 08, 2004 9:02 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 3:43 am

Quoting PhilSquares (Reply 5):
I beg to differ. Speaking ONLY for the 744 you can take full tanks, 360 passengers and 7.2 tons of bags/cargo. That puts you right at MTOW.

True, but that's not max payload for the 744. At max payload you're limited by about 20t of fuel.

Also, i think LHs A340's are only 2-class soo that may effect those figures.

Everyone has chirped on that the 744 has the best CASM of them all but it's never really been explained in depth. I would welcome such an analysis.
 
Lufthansa
Posts: 2303
Joined: Thu May 20, 1999 6:04 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 3:59 am

Quoting RJ111 (Reply 8):
Everyone has chirped on that the 744 has the best CASM of them all but it's never really been explained in depth. I would welcome such an analysis.

Yeah and that figuare also came about before the 77W came into service. I imagine that may change things slightly.
 
N1120A
Posts: 26467
Joined: Sun Dec 14, 2003 5:40 pm

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 4:04 am

Quoting EHHO (Reply 2):
An A343 carries 303 pax in 3-class config, and 335 in 2-class. The B744 carries 416 pax in 3-class config, and anywhere between 500 and 568 in 2-class.

Those numbers are completely off.

Quoting RJ111 (Reply 8):
Everyone has chirped on that the 744 has the best CASM of them all but it's never really been explained in depth. I would welcome such an analysis.

It is called economies of scale. While the 744 burns more fuel because of its larger size, it also carries significantly more passengers than anything flying. Further, the flight crew is the same size as any other aircraft on a comparable stage length. Additionally, the aircraft costs the same to park at a gate and the same number of slots at an airport.

Quoting Lufthansa (Reply 9):
Yeah and that figuare also came about before the 77W came into service. I imagine that may change things slightly.

It still doesn't. The 744 still has the lower CASM, as it has an 80 seat advantage in a similar configuration.
Mangeons les French fries, mais surtout pratiquons avec fierte le French kiss
 
Adria
Posts: 781
Joined: Wed Aug 09, 2000 7:53 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 4:35 am

CASM is one thing and total fuel consumption another. The A343 actually has a lower total fuel consumption than the 772ER...
 
Leskova
Posts: 5547
Joined: Wed Oct 08, 2003 3:39 pm

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 5:15 am

Quoting RJ111 (Reply 8):
Also, i think LHs A340's are only 2-class soo that may effect those figures.

The A340-300s are either all, or for the most part, 3-class; the -600s are mostly 2-class, but the still to be delivered ones will also feature 3-class cabins (though, again, I'm not certain if it's all of them or just some of them).
Smile - it confuses people!
 
PolymerPlane
Posts: 832
Joined: Thu May 11, 2006 1:12 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 7:27 am

Quoting EHHO (Reply 2):

totally wrong analysis. First you quote fuel burn as the maximum capacity of the fuel tanks. Range for 744 is about 7260NM. Clearly it won't need all the fuel it can carry. Second, you probably won't fly at MTOW for 5000NM run. Third, you have to calculate cargo revenue as well if you really want to be rigorous.

Cheers,
PP
One day there will be 100% polymer plane
 
mikkel777
Posts: 361
Joined: Thu Oct 03, 2002 1:15 am

RE: Which A/c Burns Alot Of Fuel B747-400 Or A340-300?

Sun Oct 29, 2006 9:49 am

I'm going to make this very very easy.
The 747 has much more powerful engines, that has a higher FF, so the 747 will use more fuel.
The OP never mentioned anyting about pr seat....
IRCC the 747 is app 50% heavier and the engines produces 50% more power. Roughly.
Since the engines are app on the same technology level, one can expect the fuel burn to be quite a bit more on the 74's

Enjoy my superscientific analasys

Who is online

Users browsing this forum: No registered users and 19 guests