Hi Everyone, I was wondering the fuel consumption of the new generation aircraft from Boeing and Airbus.

I would like to compare the TRIP fuel needed of both B789 & A359 on a the following case :

- Route : LFPG / KJFK / LFPG

- Acfts : B787-900 & A350-900

- Payload : 32 tons

- FL 400 LFPG => KJFK

- FL 410 KJFK => LFPG

- Cruise M 0.85

Thanks for your feedbacks,

The A359 part is also very interesting.

Not really. One route, low payload, low range. Lighter plane wins by a fair margin. Comparison with A339 would be much more interesting, but possible probably in 1-2 years.

gloom wrote:

Not really. One route, low payload, low range. Lighter plane wins by a fair margin. Comparison with A339 would be much more interesting, but possible probably in 1-2 years.

So true, but lets compare the actuals "most advanced" acfts on the market on a very busy route.

The A350-900 is approximately 10% larger than the 787-9. Both aircraft are long to ultra-long capable.

If they are carrying the same payload, the A350-900 would have about 10% more empty seats and about 10% more empty LD3 slots (or cargo weight). The trips fuel would definitely be lower for the smaller aircraft.

thanks all for your feedbacks. You guys are confirming what the débats of the MOM VS A330 Neo is about.

Do you guys agrees with the following " On route less than 10 hours / cap 300-350 pax, the most advanced acfts doesnt make difference compared to the CEO acfts generation.

Im talking about the fuel burn only indeed

I'm not quite sure I get your point, but assuming I have.

When the new generation comes now, it gets 15-25% lower fuel burn figures. Out of that, approx 2 to 5 % is the aero refinement, rest goes to engines progress. So basically, any NEO plane would do lower numbers (A claims NEO to be at 16% lower than CEO), but mostly due to engines. If we manage to put two planes, 90s generation, and modern clean sheet at similar OEW, we get 20%. However, clean sheet plane will also be lighter, hence raising the difference into approx. 25% reduction.

This is basically the difference we see. NEO can get well within clean sheet plane, only a few (2-5) percent difference.

Of course, getting extra weight (higher OEW/MTOW) or opposite - lighter design weight in case of clean sheet plane - could shift the difference.

Cheers,
Adam

gloom wrote:

This is basically the difference we see. NEO can get well within clean sheet plane, only a few (2-5) percent difference.

The only case where we see this is Airbus A330 vs. Boeing 787.
( craft man's product vs a PR guys colorful dreams

A 767NEO would not be up to snuff and the
777X exists because a 77WNEO would still be 15% worse than the A3510.
Same for 757. Even with new engines a distant second to the A321LRs fuel use.

gloom wrote:

Not really. One route, low payload, low range. Lighter plane wins by a fair margin. Comparison with A339 would be much more interesting, but possible probably in 1-2 years.

You can have your fun later. Show the 789 vs A359 numbers first.
May be there is a surprise hidden in there.

Afair ?Zeke? some time ago offered numbers that shew A359 using less block fuel than a 789 on a select route.
( can't find where that was posted here.)

WIederling wrote:

You can have your fun later. Show the 789 vs A359 numbers first.
May be there is a surprise hidden in there.

I'm a 359 fan myself, but on hop like that, and 30t payload, it's way below where 359 performs best (high loads). Since I can only quote others, as I have no access to raw data, I estimate the difference here to be around 3% in favor of 789 (lighter frame), based on previous reports (but it's only an estimation).

If we were going with 40+t and in 5000nm mission, I'd say that's probably more-or-less equal point, and with latest PIPs, 359 could be breaking into top position. But it's not the case here.

BTW, just curious what would be L/D for 359. I'd risk it's quite close to 789, gains to overcome additional weight on trip fuel on long missions are from Trents.

Cheers,
Adam

gloom wrote:

BTW, just curious what would be L/D for 359. I'd risk it's quite close to 789, gains to overcome additional weight on trip fuel on long missions are from Trents.

Wouldn't higher weights combined with a fuel use advantage over longer ranges indicate a better L/D for the A359?

This stuff is so misleading that for practical purposes you cannot do a meaningful comparison on a website like this.

gloom wrote:

If we were going with 40+t and in 5000nm mission, I'd say that's probably more-or-less equal point, and with latest PIPs, 359 could be breaking into top position. But it's not the case here.

BTW, just curious what would be L/D for 359. I'd risk it's quite close to 789, gains to overcome additional weight on trip fuel on long missions are from Trents.

At FL370, We have the following L/D ratio for the following planes:

A359: 21.12
789: 20.77
77W: 20.07
779: 21.27
A380: 20.08
748: 19.17

Those figures were calculated by Ferpe.

Eyad89 wrote:

At FL370, We have the following L/D ratio for the following planes:
A359: 21.12
789: 20.77
77W: 20.07
779: 21.27
A380: 20.08
748: 19.17
Those figures were calculated by Ferpe.

Thanks.
Interesting the 779X is marginally better than the 359 but "buys" that with a disproportionately large step up in OEW
while 789 and 359 aren't far apart in OEW ( less than their capacity delta ).

T1000TEN/T7000 will be on par with the TXWB sfc wise?

WIederling wrote:

Eyad89 wrote:

At FL370, We have the following L/D ratio for the following planes:
A359: 21.12
789: 20.77
77W: 20.07
779: 21.27
A380: 20.08
748: 19.17
Those figures were calculated by Ferpe.

Thanks.
Interesting the 779X is marginally better than the 359 but "buys" that with a disproportionately large step up in OEW
while 789 and 359 aren't far apart in OEW ( less than their capacity delta ).

The 779 is also larger than the A359. That could also explain a large OEW delta. You can't say the OEW difference was due solely to L/D improvement.

OldAeroGuy wrote:

The 779 is also larger than the A359. That could also explain a large OEW delta. You can't say the OEW difference was due solely to L/D improvement.

AFAIK the 779 is said to gain 19t OEW versus the 77W while MTOW stays constant.
( that can't stem from that piddling stretch of the fuselage.

WIederling wrote:

OldAeroGuy wrote:

The 779 is also larger than the A359. That could also explain a large OEW delta. You can't say the OEW difference was due solely to L/D improvement.

AFAIK the 779 is said to gain 19t OEW versus the 77W while MTOW stays constant.
( that can't stem from that piddling stretch of the fuselage.

You also can't say that the OEW differences between the 773ER and the 779 are solely due to L/D improvement. Other reasons for the OEW increase can be:

Body stretch
Cabin furnishings for more passengers
Engine changes to improve TSFC (larger fan and core changes for 60:1 compression ratio)
More wing area to allow 9% lower engine thrust at same MTOW as the 77W
Empennage changes to accommodate the larger wing area

The major L/D improvement configuration changes would:

Increased span and associated wing fold mechanism.

Only OEW changes for these items can be book kept against the total OEW change.

OldAeroGuy wrote:

WIederling wrote:

OldAeroGuy wrote:

The 779 is also larger than the A359. That could also explain a large OEW delta. You can't say the OEW difference was due solely to L/D improvement.

AFAIK the 779 is said to gain 19t OEW versus the 77W while MTOW stays constant.
( that can't stem from that piddling stretch of the fuselage.

You also can't say that the OEW differences between the 773ER and the 779 are solely due to L/D improvement. Other reasons for the OEW increase can be:

Body stretch
Cabin furnishings for more passengers
Engine changes to improve TSFC (larger fan and core changes for 60:1 compression ratio)
More wing area to allow 9% lower engine thrust at same MTOW as the 77W
Empennage changes to accommodate the larger wing area

The major L/D improvement configuration changes would:

Increased span and associated wing fold mechanism.

Only OEW changes for these items can be book kept against the total OEW change.

round number
20t
- 3t ( stretch and more pax seating )
- 1t ( larger empenage )
- 0t ( MLG stays the same.)
-2.4t ( GE9X weight delta, a guess. modelled after Trent900 to TXWB increase )
== 13t for a wider wingspan and more area.

A380MSN004 wrote:

Hi Everyone, I was wondering the fuel consumption of the new generation aircraft from Boeing and Airbus.

I would like to compare the TRIP fuel needed of both B789 & A359 on a the following case :

- Route : LFPG / KJFK / LFPG

- Acfts : B787-900 & A350-900

- Payload : 32 tons

- FL 400 LFPG => KJFK

- FL 410 KJFK => LFPG

- Cruise M 0.85

Thanks for your feedbacks,

I find it odd how we can have a 787-9 vs A350-900 debate in response to your question without anyone coming close to answering your question or providing trip fuel numbers

Newbiepilot wrote:

A380MSN004 wrote:

Hi Everyone, I was wondering the fuel consumption of the new generation aircraft from Boeing and Airbus.

I would like to compare the TRIP fuel needed of both B789 & A359 on a the following case :

- Route : LFPG / KJFK / LFPG

- Acfts : B787-900 & A350-900

- Payload : 32 tons

- FL 400 LFPG => KJFK

- FL 410 KJFK => LFPG

- Cruise M 0.85

Thanks for your feedbacks,

I find it odd how we can have a 787-9 vs A350-900 debate in response to your question without anyone coming close to answering your question or providing trip fuel numbers

Well thanks to Bravo One we had the numbers for the 789. But None come up with the 359 for the moment.

Newbiepilot wrote:

I find it odd how we can have a 787-9 vs A350-900 debate in response to your question without anyone coming close to answering your question or providing trip fuel numbers

Really surprised? It's a direct A vs B comparison, as unfair against A as possible (short route, low load). And once calculated, it will be used to prove "B is better than A", without using route/payload as assumption.

A380MSN004 wrote:

Well thanks to Bravo One we had the numbers for the 789. But None come up with the 359 for the moment.

On the other hand, there's no airline using 350 on the route specified. It takes extra effort and profiled software to crunch the numbers. Considering above, why waste anyone's precious time and computing time on never-to-happen scenario?

Cheers,
Adam

gloom wrote:

Newbiepilot wrote:

I find it odd how we can have a 787-9 vs A350-900 debate in response to your question without anyone coming close to answering your question or providing trip fuel numbers

Really surprised? It's a direct A vs B comparison, as unfair against A as possible (short route, low load). And once calculated, it will be used to prove "B is better than A", without using route/payload as assumption.

A380MSN004 wrote:

Well thanks to Bravo One we had the numbers for the 789. But None come up with the 359 for the moment.

On the other hand, there's no airline using 350 on the route specified. It takes extra effort and profiled software to crunch the numbers. Considering above, why waste anyone's precious time and computing time on never-to-happen scenario?

Cheers,
Adam

I’d do it, if I had available data... A vs B competition? Why would we care, the numbers are what they are, regardless of what we argue here I would love to see myself how they compare...

thepinkmachine wrote:

I’d do it, if I had available data... A vs B competition? Why would we care, the numbers are what they are, regardless of what we argue here I would love to see myself how they compare...

Well, right, just a number. How about LFPG-WSSS for a longer route, and say.. 40t payload? I wonder what would it be, just to stick against the case above
It's just a number anyway

Cheers, Adam

A380MSN004 wrote:

Hi Everyone, I was wondering the fuel consumption of the new generation aircraft from Boeing and Airbus.

I would like to compare the TRIP fuel needed of both B789 & A359 on a the following case :

- Route : LFPG / KJFK / LFPG

- Acfts : B787-900 & A350-900

- Payload : 32 tons

- FL 400 LFPG => KJFK

- FL 410 KJFK => LFPG

- Cruise M 0.85

Thanks for your feedbacks,

This topic has come up a number of times. The 789 has about a 4% lower fun burn up to about 5500nm. At very long range the advantage swings to the 359.

I have not seen the comparison at different payload levels.

gloom wrote:

thepinkmachine wrote:

I’d do it, if I had available data... A vs B competition? Why would we care, the numbers are what they are, regardless of what we argue here I would love to see myself how they compare...

Well, right, just a number. How about LFPG-WSSS for a longer route, and say.. 40t payload? I wonder what would it be, just to stick against the case above
It's just a number anyway

Cheers, Adam

Block Fuel : 76644 kg