Page 1 of 2

A350-1000 fuel burn

Posted: Wed Dec 04, 2019 11:15 pm
by ITSTours
https://twitter.com/JournoDannyAero/sta ... 41/photo/1

Danny Lee, an aviation journalist at SCMP, has provided the data point from the crews.

The crew wrote that the cruising fuel burn at FL390 was 6.3t/hour.
S/he also noted B747 would have burnt 10.0t/hour at the same payload.
The actual payload, or the TOW, is unfortunately not provided.

Still, looks great!

Re: A350-1000 fuel burn

Posted: Thu Dec 05, 2019 4:47 pm
by flipdewaf
It seems to me that the crew have just given a generic statement about the expected level of fuel burn rather than what it was. Given that FL390 was stated and the available altitudes on the westbound leg would be the "even" Flight levels (340, 360, 380 etc) then it can have been from the specific flight.

Zeke has in the past been able to use the manuals from the aircraft he flies (A350) to guess the takeoff weights from the given V1, Vr and V2 speeds the the weather report from the day/location.

Fred

Re: A350-1000 fuel burn

Posted: Thu Dec 05, 2019 6:07 pm
by zeke
flipdewaf wrote:
It seems to me that the crew have just given a generic statement about the expected level of fuel burn rather than what it was. Given that FL390 was stated and the available altitudes on the westbound leg would be the "even" Flight levels (340, 360, 380 etc) then it can have been from the specific flight.

Zeke has in the past been able to use the manuals from the aircraft he flies (A350) to guess the takeoff weights from the given V1, Vr and V2 speeds the the weather report from the day/location.

Fred


Looking at the weather on a November 25 @ 12:33 GMT

METAR EGLL 252320Z AUTO 21005KT 9999 BKN013 OVC022 11/11 Q1001 NOSIG=

Based off that data, the runway 09R at LHR and the V speeds means they were taking off around 275 tonnes, which would have seen them land at near MLW.

Re: A350-1000 fuel burn

Posted: Thu Dec 05, 2019 6:20 pm
by strfyr51
ITSTours wrote:
https://twitter.com/JournoDannyAero/status/1202066015892336641/photo/1

Danny Lee, an aviation journalist at SCMP, has provided the data point from the crews.

The crew wrote that the cruising fuel burn at FL390 was 6.3t/hour.
S/he also noted B747 would have burnt 10.0t/hour at the same payload.
The actual payload, or the TOW, is unfortunately not provided.

Still, looks great!

Since the 2 airplanes are not even similar? What difference would the statement make? Why not compare the fuel burn of the 777-300ER or the 787-10? That statement is irrelevant! Maybe compare the fuel burn of the A380. It proves Nothing!

Re: A350-1000 fuel burn

Posted: Thu Dec 05, 2019 6:31 pm
by tommy1808
strfyr51 wrote:
ITSTours wrote:
https://twitter.com/JournoDannyAero/status/1202066015892336641/photo/1

Danny Lee, an aviation journalist at SCMP, has provided the data point from the crews.

The crew wrote that the cruising fuel burn at FL390 was 6.3t/hour.
S/he also noted B747 would have burnt 10.0t/hour at the same payload.
The actual payload, or the TOW, is unfortunately not provided.

Still, looks great!

Since the 2 airplanes are not even similar? What difference would the statement make? Why not compare the fuel burn of the 777-300ER or the 787-10? That statement is irrelevant! Maybe compare the fuel burn of the A380. It proves Nothing!


With the A351 replacing the 744 at BA, and both carrying the same payload, BA saved 37% on its fuel bill for ~same revue. I am sure for BA it's pretty meaningful.

Best regards
Thomas

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 7:46 am
by gloom
flipdewaf wrote:
Given that FL390 was stated and the available altitudes on the westbound leg would be the "even" Flight levels (340, 360, 380 etc) then it can have been from the specific flight.


Fred, you forgot it's NAT. If they flew on track, they've had all available Fs (starting from F310, all the way up to F390). And yes, NAT is RVSM airspace.

Cheers,
Adam

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 9:54 am
by MoKa777
Anyone know what the estimated payload would have been for this flight?

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 10:01 am
by BA777FO
That sounds about right (obviously is as it has come from the crew). To YYZ and DXB the A350-1000, at similar payloads, has a very similar trip fuel burn to the 777-200ER.

So the A350-1000 is pretty much 77W size but with a 777-200 fuel burn. The 77W burns roughly a tonne more than the 772 per hour so the A350-1000 is roughly a tonne per hour better than the 77W, so over an 8 hour flight, 8 tonnes is about $4,000-5,000 worth of fuel savings. Not bad, but not the huge leap that the 787-9 has over the 772.

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 10:33 am
by gloom
BA777FO wrote:
Not bad, but not the huge leap that the 787-9 has over the 772.


Sure not. But I guess you know you are comparing a planes of the same generation, but 25% difference in size?

Heck, it's like comparing 772 to 763. ;)

Cheers,
Adam

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 10:36 am
by Francoflier
Those really only are ballpark figures designed to show a non aviation-savvy audience how much more efficient modern airplanes are compared to their predecessors.

It is not of much use for a more detailed analysis of the overall fuel burn.

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 12:29 pm
by BA777FO
gloom wrote:
BA777FO wrote:
Not bad, but not the huge leap that the 787-9 has over the 772.


Sure not. But I guess you know you are comparing a planes of the same generation, but 25% difference in size?

Heck, it's like comparing 772 to 763. ;)

Cheers,
Adam


Of course, there is a big difference in size, I was just astounded how much less the 787-9 burned compared to the 772 on a route like LHR-IAH - it's virtually 20%-25% less. It'll be interesting to see what kind of fuel burn figures the 787-10 gives when it starts operating to Atlanta in February. They should be very similar sizes, albeit the 787 will be in a much more premium configuration for BA.

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 1:55 pm
by xwb565
Since it was asked up thread... The fuel burn difference for the a35k and 77w is ~1.4t per hour on a long haul sector with the a35k carrying more payload. Note this is a snapshot from only one sector albeit over multiple flights.

Re: A350-1000 fuel burn

Posted: Fri Dec 06, 2019 2:51 pm
by flipdewaf
gloom wrote:
flipdewaf wrote:
Given that FL390 was stated and the available altitudes on the westbound leg would be the "even" Flight levels (340, 360, 380 etc) then it can have been from the specific flight.


Fred, you forgot it's NAT. If they flew on track, they've had all available Fs (starting from F310, all the way up to F390). And yes, NAT is RVSM airspace.

Cheers,
Adam


Thanks Gloom! Every day's a school day after all!

Fred

Re: A350-1000 fuel burn

Posted: Sat Dec 07, 2019 3:35 am
by jetmech
The ramp fuel for the 35K SYD-DOH is between 111-115 tonnes with around 8 tonnes left over on arrival.

Regards, JetMech

Re: A350-1000 fuel burn

Posted: Sat Dec 07, 2019 10:27 am
by xwb565
Another interesting fact is that the a35k basic weight is a substantial 20t less than the 77w.

Re: A350-1000 fuel burn

Posted: Thu May 14, 2020 3:17 am
by xwb565
https://www.youtube.com/watch?v=8gzhhxULOvQ

The official video from QR's inaugural a35k flight to GRU reveals the following. ZFW around 185t,fuel on board 122.3 ton, tow around 307 ton, trip time 15:47min and fuel used 108.5t. This results in a fuel burn of 6.88 ton per hour. Factors to keep in mind- QR has probably the heaviest a35k interior and they had around 9 tons of tow to spare. They were also landing with more reserve fuel than most routes normally require. Based on knowledge of other carrier's a35k weights(and adding a margin for the qsuite weight), payload for QR should have been around 33-34t on this flight. With the tow head room they could have carried substantially more or flown longer.

Re: A350-1000 fuel burn

Posted: Thu May 14, 2020 4:43 am
by DylanHarvey
xwb565 wrote:
https://www.youtube.com/watch?v=8gzhhxULOvQ

The official video from QR's inaugural a35k flight to GRU reveals the following. ZFW around 185t,fuel on board 122.3 ton, tow around 307 ton, trip time 15:47min and fuel used 108.5t. This results in a fuel burn of 6.88 ton per hour. Factors to keep in mind- QR has probably the heaviest a35k interior and they had around 9 tons of tow to spare. They were also landing with more reserve fuel than most routes normally require. Based on knowledge of other carrier's a35k weights(and adding a margin for the qsuite weight), payload for QR should have been around 33-34t on this flight. With the tow head room they could have carried substantially more or flown longer.

Seems to be completely inline with specs, even possibly beating them a tad bit, Airbus nailed the 35K.

Re: A350-1000 fuel burn

Posted: Tue May 19, 2020 10:42 am
by flipdewaf
xwb565 wrote:
https://www.youtube.com/watch?v=8gzhhxULOvQ

The official video from QR's inaugural a35k flight to GRU reveals the following. ZFW around 185t,fuel on board 122.3 ton, tow around 307 ton, trip time 15:47min and fuel used 108.5t. This results in a fuel burn of 6.88 ton per hour. Factors to keep in mind- QR has probably the heaviest a35k interior and they had around 9 tons of tow to spare. They were also landing with more reserve fuel than most routes normally require. Based on knowledge of other carrier's a35k weights(and adding a margin for the qsuite weight), payload for QR should have been around 33-34t on this flight. With the tow head room they could have carried substantially more or flown longer.


Very nice and useful information. I have a small spreadsheet on the go where I log known flight data that is suitable to calculate a range factor, this fits the bill and is the first I have from teh A350-1000.

Thanks,

Fred

Re: A350-1000 fuel burn

Posted: Mon May 25, 2020 4:45 pm
by chrisXWB
Looks very disappointing to me. 787-10 can do much better. If I recall correctly the fuel burn number for a fully loaded 787-10 is around 5.4t/hour.

Re: A350-1000 fuel burn

Posted: Mon May 25, 2020 5:40 pm
by enzo011
chrisXWB wrote:
Looks very disappointing to me. 787-10 can do much better. If I recall correctly the fuel burn number for a fully loaded 787-10 is around 5.4t/hour.



Hello apples, meet my oranges. What is the range for a fully loaded 78X? What is the range for a 78X with 33t payload? What is the comparable capacity of the 78X when looking at the QR layout in the A35K? This is before we even think of adding crew rests in the 78X to fly 15-16 hours.

Re: A350-1000 fuel burn

Posted: Mon May 25, 2020 6:07 pm
by flipdewaf
chrisXWB wrote:
Looks very disappointing to me. 787-10 can do much better. If I recall correctly the fuel burn number for a fully loaded 787-10 is around 5.4t/hour.

My PA-38 traumahawk does 0.023t/hour so clearly is the better aircraft!


Sent from my iPhone using Tapatalk

Re: A350-1000 fuel burn

Posted: Mon May 25, 2020 9:14 pm
by zeke
chrisXWB wrote:
Looks very disappointing to me. 787-10 can do much better. If I recall correctly the fuel burn number for a fully loaded 787-10 is around 5.4t/hour.


from Jayunited in another thread

"That is not true at all. Take for example today's 5/29/2019 UA85 TLV-EWR flight the MTOG for the 78X is 560,000 today's TOG was 559,235. Now before you said I told you so lets take a look at what is on that aircraft. First and foremost the aircraft went out full with 318 passengers and 326 bags and 26,089 pounds of cargo. Lets break it all down the OEW is 300,563 the weight of all 318 passengers is 60,903, the weight of their 326 bags is 9780 pounds and there was 26,089 pounds of cargo add those number together we get a ZFW of 397,335 out of a MXFW of 425,000. The cleared fuel was 161,900 so when you add the cleared fuel to the ZFW you get a TOG of 559,235.

The block time for UA85 is 11 hours 9 minutes, so as you can see the 78X is a very capable aircraft it can fly 11 hour missions and take everything while going out with a full load. If this flight had a block time of 12 hours UA could still fly the route with this aircraft but would have to sacrifice some of that 26,089 pounds of cargo. An 8 hour mission would be something like FRA-EWR or BCN-EWR both of which are on the 78X and neither flight is anywhere close to be weight restricted."

That is more like 6 tonnes per hour.


flipdewaf wrote:
My PA-38 traumahawk does 0.023t/hour so clearly is the better aircraft!


You have survived the traumahawk, hope you have the stall strips installed on yours, and regularly get that tail/boom checked for cracks.

Re: A350-1000 fuel burn

Posted: Mon May 25, 2020 10:04 pm
by flipdewaf
zeke wrote:

You have survived the traumahawk, hope you have the stall strips installed on yours, and regularly get that tail/boom checked for cracks.


Not actually mine, the flying school owns it and I haven’t flown in a while. I know this is off topic but my brother calls it the reliant robin with wings. The funny aspect of it to me is that we avoid runway lights with the wheels because cabin trim falls off!

Fred


Sent from my iPhone using Tapatalk

Re: A350-1000 fuel burn

Posted: Tue May 26, 2020 1:11 am
by DylanHarvey
chrisXWB wrote:
Looks very disappointing to me. 787-10 can do much better. If I recall correctly the fuel burn number for a fully loaded 787-10 is around 5.4t/hour.

So the A35K is a 17hr aircraft with 33t of payload. the 78X is roughly 12-13hrs. Case closed. The A35K can fly its MZFW as far as your 78X can fly with 33t of payload more or less. Case now shut down.

Re: A350-1000 fuel burn

Posted: Tue May 26, 2020 5:39 am
by DCA350
Does anybody have 777W numbers for comparison? I've only seen the A350K compared to the 747 by BA.

Re: A350-1000 fuel burn

Posted: Tue May 26, 2020 7:28 pm
by DylanHarvey
DCA350 wrote:
Does anybody have 777W numbers for comparison? I've only seen the A350K compared to the 747 by BA.

For a 16hr flight I'm guessing based on numbers that have been thrown around the 35K will carry a bit more payload, and burn about 1000kg less per hour. The A35K is lighter, someone can confirm, but between 148-153t based on the configuration. the 77W is closer to 170-175t from what I've seen.

Re: A350-1000 fuel burn

Posted: Tue May 26, 2020 10:11 pm
by DCA350
DylanHarvey wrote:
DCA350 wrote:
Does anybody have 777W numbers for comparison? I've only seen the A350K compared to the 747 by BA.

For a 16hr flight I'm guessing based on numbers that have been thrown around the 35K will carry a bit more payload, and burn about 1000kg less per hour. The A35K is lighter, someone can confirm, but between 148-153t based on the configuration. the 77W is closer to 170-175t from what I've seen.


Thanks, impressive numbers. The future looks bright depending on how the world responds Post Covid.

Re: A350-1000 fuel burn

Posted: Tue May 26, 2020 10:27 pm
by DylanHarvey
DCA350 wrote:
DylanHarvey wrote:
DCA350 wrote:
Does anybody have 777W numbers for comparison? I've only seen the A350K compared to the 747 by BA.

For a 16hr flight I'm guessing based on numbers that have been thrown around the 35K will carry a bit more payload, and burn about 1000kg less per hour. The A35K is lighter, someone can confirm, but between 148-153t based on the configuration. the 77W is closer to 170-175t from what I've seen.


Thanks, impressive numbers. The future looks bright depending on how the world responds Post Covid.

Most definitely. Can’t wait to fly on the 350, I enjoyed the 787.

Re: A350-1000 fuel burn

Posted: Wed May 27, 2020 12:12 pm
by Jefford717
chrisXWB wrote:
Looks very disappointing to me. 787-10 can do much better. If I recall correctly the fuel burn number for a fully loaded 787-10 is around 5.4t/hour.


Let me make it simple for you. These are some general rule regarding 787 vs A350 payload range.

787-9: 250-285 pax for flights < 15 hours, <250 pax for >15 hr.

787-10: 300-350 pax for flights < 12 hours.

A350-900: 275-300 pax for flights < 15 hours, <275 pax for >15 hr.

A350-1000: 300-350 pax for flights 12-16 hours.

Obviously, those figures are just some general rule and can vary greatly from airline to airline.

Belly cargo is also another factor that needs to be considered because it can greatly impact an aircraft’s performance.

I have the 787-10 and A350-1000 having the same 300-350 pax since longer haul aircraft tend to be more premium and requires more catheter hence the lower density seat for the -1000 despite being longer.

Re: A350-1000 fuel burn

Posted: Wed May 27, 2020 4:36 pm
by MrHMSH
chrisXWB wrote:
DylanHarvey wrote:
Assuming 275pax for the 359 at 15hrs, thats only 26-27t of payload, the 359 can get 40+ tons of payload past 15hrs.


You can't be serious. A 280t A359 needs to get down to ~170 passenger in order to fly LAX-SIN.


Flying 170 passengers from LAX-SIN is a choice by SQ. SQ's earliest (non-ULR) A350s can make it from SFO-SIN with 253 passengers quite easily, I believe they are 275T. More worrying for your narrative is PR's MNL-YYZ and MNL-JFK routes, they are flown with 280T A359s equipped with 295 seats. MNL-JFK is about 250 miles short of LAX-SIN, but that's still more than enough to disprove your assertion that a 280T A359 needs to get down to 170 passengers to fly LAX-SIN.

The utter insistence by a large number of posters that the A350 can't fly as far as claimed is becoming quite frustrating.

Re: A350-1000 fuel burn

Posted: Wed May 27, 2020 4:57 pm
by ua900
Y'all please refrain from insulting one another and provide sources when stating facts to contribute constructively.

Thanks!

A350-1000 fuel burn

Posted: Wed May 27, 2020 5:17 pm
by flipdewaf
MrHMSH wrote:
chrisXWB wrote:
DylanHarvey wrote:
Assuming 275pax for the 359 at 15hrs, thats only 26-27t of payload, the 359 can get 40+ tons of payload past 15hrs.


You can't be serious. A 280t A359 needs to get down to ~170 passenger in order to fly LAX-SIN.


Flying 170 passengers from LAX-SIN is a choice by SQ. SQ's earliest (non-ULR) A350s can make it from SFO-SIN with 253 passengers quite easily, I believe they are 275T. More worrying for your narrative is PR's MNL-YYZ and MNL-JFK routes, they are flown with 280T A359s equipped with 295 seats. MNL-JFK is about 250 miles short of LAX-SIN, but that's still more than enough to disprove your assertion that a 280T A359 needs to get down to 170 passengers to fly LAX-SIN.

The utter insistence by a large number of posters that the A350 can't fly as far as claimed is becoming quite frustrating.

PRs A359s are 278t I thought?

I also agree with ua900, we should stop insulting two another
Fred


Sent from my iPhone using Tapatalk

Re: A350-1000 fuel burn

Posted: Wed May 27, 2020 5:59 pm
by DylanHarvey
flipdewaf wrote:
MrHMSH wrote:
chrisXWB wrote:

You can't be serious. A 280t A359 needs to get down to ~170 passenger in order to fly LAX-SIN.


Flying 170 passengers from LAX-SIN is a choice by SQ. SQ's earliest (non-ULR) A350s can make it from SFO-SIN with 253 passengers quite easily, I believe they are 275T. More worrying for your narrative is PR's MNL-YYZ and MNL-JFK routes, they are flown with 280T A359s equipped with 295 seats. MNL-JFK is about 250 miles short of LAX-SIN, but that's still more than enough to disprove your assertion that a 280T A359 needs to get down to 170 passengers to fly LAX-SIN.

The utter insistence by a large number of posters that the A350 can't fly as far as claimed is becoming quite frustrating.

PRs A359s are 278t I thought?

I also agree with ua900, we should stop insulting two another
Fred


Sent from my iPhone using Tapatalk

I think we're all tired of the A350 bashing.

Re: A350-1000 fuel burn

Posted: Wed May 27, 2020 6:04 pm
by DylanHarvey
flipdewaf wrote:
MrHMSH wrote:
chrisXWB wrote:

You can't be serious. A 280t A359 needs to get down to ~170 passenger in order to fly LAX-SIN.


Flying 170 passengers from LAX-SIN is a choice by SQ. SQ's earliest (non-ULR) A350s can make it from SFO-SIN with 253 passengers quite easily, I believe they are 275T. More worrying for your narrative is PR's MNL-YYZ and MNL-JFK routes, they are flown with 280T A359s equipped with 295 seats. MNL-JFK is about 250 miles short of LAX-SIN, but that's still more than enough to disprove your assertion that a 280T A359 needs to get down to 170 passengers to fly LAX-SIN.

The utter insistence by a large number of posters that the A350 can't fly as far as claimed is becoming quite frustrating.

PRs A359s are 278t I thought?

I also agree with ua900, we should stop insulting two another
Fred


Sent from my iPhone using Tapatalk

And yes Fred, PR have 278t since Airbus didn't have the 280t as a non-ULR when they ordered them. I think only IB have 280t non-ULR's now, DL's newer ones might be though. I'm not positive though. Past a certain number they all have the wing-twist so the 280t is a paper upgrade IIRC.

Re: A350-1000 fuel burn

Posted: Wed May 27, 2020 11:50 pm
by MrHMSH
DylanHarvey wrote:
flipdewaf wrote:
MrHMSH wrote:

Flying 170 passengers from LAX-SIN is a choice by SQ. SQ's earliest (non-ULR) A350s can make it from SFO-SIN with 253 passengers quite easily, I believe they are 275T. More worrying for your narrative is PR's MNL-YYZ and MNL-JFK routes, they are flown with 280T A359s equipped with 295 seats. MNL-JFK is about 250 miles short of LAX-SIN, but that's still more than enough to disprove your assertion that a 280T A359 needs to get down to 170 passengers to fly LAX-SIN.

The utter insistence by a large number of posters that the A350 can't fly as far as claimed is becoming quite frustrating.

PRs A359s are 278t I thought?

I also agree with ua900, we should stop insulting two another
Fred


Sent from my iPhone using Tapatalk

And yes Fred, PR have 278t since Airbus didn't have the 280t as a non-ULR when they ordered them. I think only IB have 280t non-ULR's now, DL's newer ones might be though. I'm not positive though. Past a certain number they all have the wing-twist so the 280t is a paper upgrade IIRC.


Thanks for the correction. Reinforces my point even further though. That extra 2T means an A359 should make LAX-SIN with around 300 passengers with no issues.

Re: A350-1000 fuel burn

Posted: Thu May 28, 2020 2:22 am
by DylanHarvey
MrHMSH wrote:
DylanHarvey wrote:
flipdewaf wrote:
PRs A359s are 278t I thought?

I also agree with ua900, we should stop insulting two another
Fred


Sent from my iPhone using Tapatalk

And yes Fred, PR have 278t since Airbus didn't have the 280t as a non-ULR when they ordered them. I think only IB have 280t non-ULR's now, DL's newer ones might be though. I'm not positive though. Past a certain number they all have the wing-twist so the 280t is a paper upgrade IIRC.


Thanks for the correction. Reinforces my point even further though. That extra 2T means an A359 should make LAX-SIN with around 300 passengers with no issues.

Yes I’d say you’re right. A new A359 built right now depending on cabin is gonna be ~135-137t, close to 13.5-14hrs at MZFW. And with a full cabin and 8-10t of reserve a bit over 315-325 pax should be roughly an 17.5-18hr bird with a few tons of cargo.

Re: A350-1000 fuel burn

Posted: Thu May 28, 2020 8:12 pm
by zeke
DylanHarvey wrote:
I think only IB have 280t non-ULR's now, DL's newer ones might be though.


Our newer ones are 280 tonne non ulr.



DylanHarvey wrote:
A new A359 built right now depending on cabin is gonna be ~135-137t, close to 13.5-14hrs at MZFW.


There is a video of a finnair flight at dispatch where on the paperwork it’s under 135 tonnes.

Re: A350-1000 fuel burn

Posted: Thu May 28, 2020 8:23 pm
by DylanHarvey
DylanHarvey wrote:
zeke wrote:
DylanHarvey wrote:
I think only IB have 280t non-ULR's now, DL's newer ones might be though.


Our newer ones are 280 tonne non ulr.



DylanHarvey wrote:
A new A359 built right now depending on cabin is gonna be ~135-137t, close to 13.5-14hrs at MZFW.


There is a video of a finnair flight at dispatch where on the paperwork it’s under 135 tonnes.

OK that’s what I figured. I wasn’t sure if you guys still went with 275 or 277. I mainly added the 135 to 137 range for parity lol. I am just curious what The 1000’s are now? I’m guessing around 148t? Giving a max payload of 73t?

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 2:48 am
by jetmech
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 3:13 am
by DylanHarvey
jetmech wrote:
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech

That is insane though. 77W with basically equal or less than 77E and 343 fuel burn. WOW. So basically at 319t its close to an 18hr bird with a full house of 360 something pax. Wow.

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 4:09 am
by LH707330
DylanHarvey wrote:
jetmech wrote:
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech

That is insane though. 77W with basically equal or less than 77E and 343 fuel burn. WOW. So basically at 319t its close to an 18hr bird with a full house of 360 something pax. Wow.

Curious about that last comparison between the 77W, 77E, and 343, are you saying they all burn around the same?

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 9:57 am
by MoKa777
jetmech wrote:
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech


That is very interesting.

What was the actual TOW?

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 10:00 am
by MoKa777
LH707330 wrote:
DylanHarvey wrote:
That is insane though. 77W with basically equal or less than 77E and 343 fuel burn. WOW. So basically at 319t its close to an 18hr bird with a full house of 360 something pax. Wow.

Curious about that last comparison between the 77W, 77E, and 343, are you saying they all burn around the same?


I believe he means an aircraft the size of and with the capacity of a 77W burning less fuel per unit time or distance than a 77E or A343.

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 10:19 am
by xwb565
jetmech wrote:
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech


Colder temps at cruise?

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 11:03 am
by flipdewaf
xwb565 wrote:
jetmech wrote:
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech


Colder temps at cruise?


It does seem like an oddly low figure for the fuel burn. Taking off at 316t and burning 91.4t means its landing at ~224t. With Ramp Fuel load of 98.3t the zero fuel weight was 217.3t which is getting fairly close to MZFW. Something seems amiss here. Do we (are we allowed) access to the actual takeoff weight? I think the flight being referred to took 14:04 according to FR24.

Fred

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 11:07 am
by xwb565
flipdewaf wrote:
xwb565 wrote:
jetmech wrote:
I just had a SYD-DOH A35K flight with a ramp fuel load of 98.3 tonnes (trip fuel of 91.4 tonnes). Interestingly, the RTOW (316 tonnes) was close to MTOW (318 tonnes) and the flight time was 14 hr 15 min which is close to typical. What would have allowed for such a low fuel load when the usual ramp fuel is around 110 tonnes? The flight time suggests that tail winds were modest at best. The exact same flight the previous night had a ramp fuel load of 111 tonnes.

Regards, JetMech


Colder temps at cruise?


It does seem like an oddly low figure for the fuel burn. Taking off at 316t and burning 91.4t means its landing at ~224t. With Ramp Fuel load of 98.3t the zero fuel weight was 217.3t which is getting fairly close to MZFW. Something seems amiss here. Do we (are we allowed) access to the actual takeoff weight? I think the flight being referred to took 14:04 according to FR24.

Fred


The a35k fuel burn can be this low but the tow was closer to 290t and payload in the mid 20s. 6.8t per hour is normal at higher weights and 7.1t per hour in really warm conditions. The cruise profile in fr24 does however suggest a high tow(initial cruise at fl320).

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 11:31 am
by flipdewaf
xwb565 wrote:
flipdewaf wrote:
xwb565 wrote:

Colder temps at cruise?


It does seem like an oddly low figure for the fuel burn. Taking off at 316t and burning 91.4t means its landing at ~224t. With Ramp Fuel load of 98.3t the zero fuel weight was 217.3t which is getting fairly close to MZFW. Something seems amiss here. Do we (are we allowed) access to the actual takeoff weight? I think the flight being referred to took 14:04 according to FR24.

Fred


The a35k fuel burn can be this low but the tow was closer to 290t and payload in the mid 20s. 6.8t per hour is normal at higher weights and 7.1t per hour in really warm conditions.


That makes total sense now. If I feed in a figure of 289.5t takeoff weight to my tables I get a range factor of within 0.1% of that for the GRU flight (which shouldn't be surprising).

Fred

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 11:36 am
by xwb565
flipdewaf wrote:
xwb565 wrote:
flipdewaf wrote:

It does seem like an oddly low figure for the fuel burn. Taking off at 316t and burning 91.4t means its landing at ~224t. With Ramp Fuel load of 98.3t the zero fuel weight was 217.3t which is getting fairly close to MZFW. Something seems amiss here. Do we (are we allowed) access to the actual takeoff weight? I think the flight being referred to took 14:04 according to FR24.

Fred


The a35k fuel burn can be this low but the tow was closer to 290t and payload in the mid 20s. 6.8t per hour is normal at higher weights and 7.1t per hour in really warm conditions.


That makes total sense now. If I feed in a figure of 289.5t takeoff weight to my tables I get a range factor of within 0.1% of that for the GRU flight (which shouldn't be surprising).

Fred


To clarify- the 290t figure is not for the QR flight jetmech is referring to. It is what I have seen with another carrier. The fr24 cruise profile for the flight Jetmech is talking about sits very well with a high tow. The fuel burn is still too low and confusing.

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 12:28 pm
by DylanHarvey
xwb565 wrote:
flipdewaf wrote:
xwb565 wrote:

The a35k fuel burn can be this low but the tow was closer to 290t and payload in the mid 20s. 6.8t per hour is normal at higher weights and 7.1t per hour in really warm conditions.


That makes total sense now. If I feed in a figure of 289.5t takeoff weight to my tables I get a range factor of within 0.1% of that for the GRU flight (which shouldn't be surprising).

Fred


To clarify- the 290t figure is not for the QR flight jetmech is referring to. It is what I have seen with another carrier. The fr24 cruise profile for the flight Jetmech is talking about sits very well with a high tow. The fuel burn is still too low and confusing.[/quote/]
At 14:04 the burn per hour was ~6.5t ish. At 290t I think the 35K would start off at 340 or 350, rather than the 320 this flight started at, and they only got 380 almost 5 hours into the flight. I’m interested to see, everything suggests this flight was actually at around 316t rather than 290t, besides the fuel burn. Doesn’t really align to burn 6.7-6.8 at 308, then 6.5-6.6 at 316 ish

Re: A350-1000 fuel burn

Posted: Tue Jun 09, 2020 2:00 pm
by jetmech
DylanHarvey wrote:
WOW. So basically at 319t its close to an 18hr bird with a full house of 360 something pax. Wow.

From memory it was only around 90 passengers going out but this was made up for with cargo.

xwb565 wrote:
Colder temps at cruise?

That could be part of it. I was thinking they had great tailwinds and took advantage of this by throttling back (i.e. normal ground speed, reduced airspeed)

MoKa777 wrote:
What was the actual TOW?

flipdewaf wrote:
It does seem like an oddly low figure for the fuel burn. Taking off at 316t and burning 91.4t means its landing at ~224t. With Ramp Fuel load of 98.3t the zero fuel weight was 217.3t which is getting fairly close to MZFW. Something seems amiss here. Do we (are we allowed) access to the actual takeoff weight? I think the flight being referred to took 14:04 according to FR24.

xwb565 wrote:
The a35k fuel burn can be this low but the tow was closer to 290t and payload in the mid 20s. 6.8t per hour is normal at higher weights and 7.1t per hour in really warm conditions. The cruise profile in fr24 does however suggest a high tow(initial cruise at fl320).

xwb565 wrote:
The fuel burn is still too low and confusing.

DylanHarvey wrote:
I’m interested to see, everything suggests this flight was actually at around 316t rather than 290t, besides the fuel burn. Doesn’t really align to burn 6.7-6.8 at 308, then 6.5-6.6 at 316 ish

The details I have available to me are;

EZFW; 187.0 t
MZFW; 223.0 t
RTOW; 316.0 t (regulated (performance) TO weight limited by Max. structural TO weight)
Ramp fuel; 98.3 t
Taxi fuel; 0.4 t
T.O. fuel; 97.9 t
Trip fuel; 91.4 t
Trip time 14hr 16min

It looks like the RTOW is the one that has confused me as I assumed that this was the TO weight. I didn't look at the ECAM to see what the actual TO weight was.

Regards, JetMech