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SQ32
Posts: 56
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Re: 787 vs A350 range

Mon Jun 17, 2019 7:42 am

We take Singapore Airlines 253 passegers, equivalent to 25t. The A350 OEW is estimated to be 142t. Add about 5t of contingency fuel. Now we have 172t. For 280t MTOW variant, we will have 108t of fuel. We know A350 consumes 5.85t/hr in a typical URL flight. So this will be an 18.5 hours bird.

EWR -> SIN is about 17.5 hours on average, 18 hours max. In reality, Singapore Airlines can fly her regular A350 for EWR -> SIN mission. She do not need the 163 pax low density ULR configuration.

IAD -> SIN should be no issue for 253 pax A350.
 
h1fl1er
Posts: 121
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Re: 787 vs A350 range

Mon Jun 17, 2019 2:35 pm

zeke wrote:
mintxwb wrote:
And the DOW you flew is not higher than 141.7 tonnes on long-haul missions? When you use your software to produce 325 seats, 268t, 8100nm, what is the DOW you use, the same as 141.7t?


We would have over a dozen different DOW configurations on the A350 depending on the sector, the DOW is not directly presented to us in the cockpit, just the ZFW. For me to work out the DOW I would need to lookup the configuration for the flight and add that to the basic weight.

I have already corrected someone earlier on this to say it was 315 seats not 325. That was the 268 tonne 3 class configuration.

This is not my software, it is the certified software loaded on the aircraft. It is used for real world performance calculations from takeoff to landing.

I am not going to say the DOW, as previously stated the fuel burn is confidential information. If I told you the DOW you know the fuel fraction, ie TOW-DOW.

All I will confirm it does not need the full 268 tonnes to do it, there is an additional margin for fuel reserves.


cool stuff.

however the math I provided does not support your assertion that the 359/268 can move 315 8100nm. it appears to be discrepant from what your software is providing as an output. in most cases this will be operator error. either way i'd like to understand why basic PR chart math seems to produce results that are hours apart from what you say a computer literally on the plane is producing.

I have the ulr at [email protected], bearing in mind it is a ton or 2 light because of the cargo hold deactivation. the std 280t should hit 7500-7600 in revenue service with a real airline. if your cabin matches airbus and your pax+bags are 95kg, then their own ACAPS says 8100 with 325 at 280t. That's 12t more fuel than you say your computer is showing.

For one case on May 27:
https://www.flightradar24.com/data/flig ... 7#20a985e2
https://flightaware.com/live/flight/PAL ... /KJFK/RPLL ),

Although the route is close to GCD (7574 NM), the on-air flight duration was 16:56. Almost 17 hours.
This is obviously because the plane met a very strong headwind; the ground speed was 380kts at one point. (I don't have FR24 paid access to the true airspeed data)
As PAL has not required a technical fuel stop or declared fuel emergency since they started this route,
the evidence is sufficient to conclude that 278t MTOW A359 with 35.6-37.1t payload (2018 US BTS data) can fly up to 17 hours.


that was just one day tho. they'd have blocked seats. UAL was doing lax-sin for months and the plane didn't have the range necessary to make it work consistently.

I think one of the issues here is a mismatch between esad and city-pair range. frequently people mix those up in the discussions. the 359 is a good match for a city pair in the mid 7000s still air range. the 789 right about the same. the 89 is flying 17.5 hrs on ua101 *routinely*. the flight in the air right now is listed at 17:20. This is in UA trim. still air on that is only 7454. but at 17:20, it's pushing it a lot further. unless they're at M.84 for a ton of the flight, which having flown that route I personally did not see nor have I noted frequently in looking up 789 flights.

does that mean that the 789's 7635 spec is "unrealistic"? No. It's useful only for an estimate at about spec people over a city pair at about 7635 apart.

max endurance for 359 flights right now is 17 on a bad day (pr127, sq31). pr is at 278t flying with -3t pax vs spec. sq 275 but sq flies -7t pax vs spec.
 
mintxwb
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Re: 787 vs A350 range

Mon Jun 17, 2019 4:27 pm

h1fl1er wrote:
For one case on May 27:
https://www.flightradar24.com/data/flig ... 7#20a985e2
https://flightaware.com/live/flight/PAL ... /KJFK/RPLL ),

Although the route is close to GCD (7574 NM), the on-air flight duration was 16:56. Almost 17 hours.
This is obviously because the plane met a very strong headwind; the ground speed was 380kts at one point. (I don't have FR24 paid access to the true airspeed data)
As PAL has not required a technical fuel stop or declared fuel emergency since they started this route,
the evidence is sufficient to conclude that 278t MTOW A359 with 35.6-37.1t payload (2018 US BTS data) can fly up to 17 hours.


that was just one day tho. they'd have blocked seats. UAL was doing lax-sin for months and the plane didn't have the range necessary to make it work consistently.


That 35.6-37.1t payload data from US BTS is average. I find it questionable to assume average payload when the headwind is particularly strong and the flight time exceeds 17 hours. I would be interesting to see the payload of JFK-MNL on the day when flight time is 17 hours. If we extrapolate from other DL and SQ flights using your math, yes, they'd have blocked seats, but still, I would love to see some more evidence.
 
tommy1808
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Re: 787 vs A350 range

Mon Jun 17, 2019 4:33 pm

mintxwb wrote:
The problem is, the "basic PR chart" agrees with multiple A359 flights in real world everyday, while the software zeke presents is hours apart from reality.


For how many flight exactly do you happen to know

a) that aircrafts exactly operating weight
b) the exact climb profile
c) how much fuel was used for taxi
d) how much cargo was on board
e) how much fuel was left at the end

And so on...

The basic PR charts can't be correct, as they dont agree with themselves. Fuel volume limit range should have gone up by close to 400nm or so for the 5T TOW alone, yet the PR chart is unchanged. MZFW range should have gone up due to improved aerodynamics, yet it didn't....


The delta is between actual flight data and numbers presented by zeke. No one has said the computers airlines use are inaccurate.


Since the Data provided by Zeke is the data the airlines, or rather his airline, are using that is exactly what you are saying. Unless you want to call him a liar that is... that photoshops his stuff on top.

Best regards
Thomas
This Singature is a safe space......
 
Mrakula
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Re: 787 vs A350 range

Mon Jun 17, 2019 8:40 pm

You do not understand what Zeke said most probably! Everything depends on enviroment. Airbus enviroment cannot be projected to other flight conditions! When you going to compare 78 and A350 capabilitiesu you are comparing flights which are at the edge of 789 performance while A359ULR has some reserve as you can see on innaugural SQ21/22 flight and also standart A359 can operate LAX-SIN like 789, but at the worst weather conditions A359 running out of fuel capacity but 789 is out of MTOW and fuel capacity together. That is why Singapore airlines schedule A359ULR for that route.
 
mintxwb
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Re: 787 vs A350 range

Mon Jun 17, 2019 9:10 pm

Mrakula wrote:
When you going to compare 78 and A350 capabilitiesu you are comparing flights which are at the edge of 789 performance while A359ULR has some reserve as you can see on innaugural SQ21/22 flight and also standart A359 can operate LAX-SIN like 789, but at the worst weather conditions A359 running out of fuel capacity but 789 is out of MTOW and fuel capacity together. That is why Singapore airlines schedule A359ULR for that route.


No you do not understand the payload/range chart. With a full SQ A359 non-ULR cabin, 253 people, payload 25t, there is no way A359 can be fuel-volume limited. It hits MTOW before being fuel volume limited. Neither SQ non-ULR A359 or UA 789 can do LAX-SIN full cabin; they are both MTOW limited. Please see the payload-range chart zeke posted. The green line is for ULR. The extra capacity is only useful when the payload is below 25t or so.

Yes SQ has to schedule A359ULR. They can't block seats on their regular A359 because, as you said, it doesn't have the fuel capacity. However, UA can block some seats on their 789 to do the same route.

If zeke were correct, i. e. 315/325 seat [email protected] is capable doing 8100nm still air, LAX-SIN should be a piece of cake for 276t 253-seat SQ non-ULR A359, full cabin, even in the worst case. It would be neither MTOW nor fuel-volume limited. They are sending ULR on that route speaks volumes. it's all about range, not because of the demand of premium seats. Again, if zeke were right, they could have added more biz seats on their non-ULR A359. Why spend the extra money for expensive 280t ULR?
Last edited by mintxwb on Mon Jun 17, 2019 9:20 pm, edited 1 time in total.
 
Mrakula
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Re: 787 vs A350 range

Mon Jun 17, 2019 9:19 pm

mintxwb wrote:
Mrakula wrote:
You do not understand what Zeke said most probably! Everything depends on enviroment. Airbus enviroment cannot be projected to other flight conditions! When you going to compare 78 and A350 capabilitiesu you are comparing flights which are at the edge of 789 performance while A359ULR has some reserve as you can see on innaugural SQ21/22 flight and also standart A359 can operate LAX-SIN like 789, but at the worst weather conditions A359 running out of fuel capacity but 789 is out of MTOW and fuel capacity together. That is why Singapore airlines schedule A359ULR for that route.


No you do not understand the payload/range chart. With a full SQ A359 non-ULR cabin, 253 people, payload 25t, there is no way A359 can be fuel limited. It hits MTOW before being fuel volume limited. Neither SQ non-ULR A359 or UA 789 can do LAX-SIN full cabin; they are both MTOW limited. Please see the payload-range chart zeke posted. The green line is for ULR. The extra capacity is only useful when the payload is below 25t or so.

Yes SQ has to schedule A359ULR. They can't block seats on their regular A359 because, as you said, it doesn't have the fuel capacity. However, UA can block some seats on their 789 to do the same route.

If zeke were correct, i. e. 315/325 seat [email protected] is capable doing 8100nm still air, LAX-SIN should be a piece of cake for 276t SQ non-ULR A359, full cabin, even in worst case. It would be neither MTOW nor fuel-volume limited. They are sending ULR on that route speaks volumes. it's all about range, not because of the demand of premium seats. Again, if zeke were right, they could have added more biz seats on their non-ULR A359. Why spend the extra money for expensive 280t ULR?


1. Zeke just copy Airbus payload range chart! Page 160

https://www.airbus.com/content/dam/corp ... 0-1000.pdf

2. Standart SQ A359 has MTOW 276T DOW should be 135-140T (earlier in the thread Zeke conting with 135T) MTOW 276T minus fuel capacity 108T minus DOW 135T you get 168T ZFW that is 33T payload. So in worst case scenario when LAX-SIN reach 18h flight time you are fuel volume limited!

Cheers
 
mintxwb
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Re: 787 vs A350 range

Mon Jun 17, 2019 9:29 pm

Mrakula wrote:
1. Zeke just copy Airbus payload range chart! Page 160
https://www.airbus.com/content/dam/corp ... 0-1000.pdf


I know.

Mrakula wrote:
2. Standart SQ A359 has MTOW 276T DOW should be 135-140T (earlier in the thread Zeke conting with 135T) MTOW 276T minus fuel capacity 108T minus DOW 135T you get 168T ZFW that is 33T payload. So in worst case scenario when LAX-SIN reach 18h flight time you are fuel volume limited!


zeke said OEW is 135-136t, not DOW. Even the Airbus range assumes DOW of 141-142t, please see zeke's previous post. Please see the second kink in the curve where the maximum fuel capacity is reached. It is clearly around 25t, not 33t. We are arguing real DOW is about 1 hour (6 tonne) or so higher than what Airbus figure uses.

https://en.wikipedia.org/wiki/Payload#R ... nd_payload
 
Mrakula
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Re: 787 vs A350 range

Mon Jun 17, 2019 9:59 pm

mintxwb wrote:
Mrakula wrote:
1. Zeke just copy Airbus payload range chart! Page 160
https://www.airbus.com/content/dam/corp ... 0-1000.pdf


I know.

Mrakula wrote:
2. Standart SQ A359 has MTOW 276T DOW should be 135-140T (earlier in the thread Zeke conting with 135T) MTOW 276T minus fuel capacity 108T minus DOW 135T you get 168T ZFW that is 33T payload. So in worst case scenario when LAX-SIN reach 18h flight time you are fuel volume limited!


zeke said OEW is 135-136t, not DOW. Even the Airbus range assumes DOW of 141-142t, please see zeke's previous post. Please see the second kink in the curve where the maximum fuel capacity is reached. It is clearly around 25t, not 33t. We are arguing real DOW is about 1 hour (6 tonne) or so higher than what Airbus figure uses.

https://en.wikipedia.org/wiki/Payload#R ... nd_payload


But earlier in the thread Zeke calculated with 135T DOW so I am little bit confused what is the right figure.

Anyway A359ULR can fly with 25t payload19h according data from SQ21/22 flights. If you look at QF9 789 can lift 25t payload to around 17-17:30h.
 
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zeke
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Re: 787 vs A350 range

Mon Jun 17, 2019 10:30 pm

Mrakula wrote:
But earlier in the thread Zeke calculated with 135T DOW so I am little bit confused what is the right figure.


Thepinkmachine and myself used landing weights in the calculations earlier in the tread. What the airline loads for catering etc is still payload, they can choose to uplift catering, cargo, fuel, or passengers with that capability. We might load three sectors worth of catering on a flight, we might tanker fuel on a flight, that is payload we have elected to carry as it often is cheaper/safer then getting at the destination. When we land however the landing weight does not know what the mass of the aircraft is comprised of, it is just looking at what fuel is needed to land with that mass after a given distance. That is why the data is presented with landing weight in the FCOM.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
Mrakula
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Re: 787 vs A350 range

Mon Jun 17, 2019 10:34 pm

Mrakula wrote:
If you look at QF9 789 can lift 25t payload to around 17-17:30h.


How do you get that, you can tell the payload by looking at a photograph ? Great big neon sign on the side saying what they have onboard ?[/quote]

Just like that:-) according to that artical https://australianaviation.com.au/2018/ ... in-london/

It is far from acurate but I would like to make simple comparison. TOW 253.5T fuel on board 100,6T 229 crew+pax (could be +/-25t with bags) 17:02h flight time. QF9 sometimes reach 17:30ish flight time. I do not insist I am right but I just want made easy clear comparison for not aducated people:-)

Cheers
 
Mrakula
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Re: 787 vs A350 range

Mon Jun 17, 2019 10:36 pm

zeke wrote:
Mrakula wrote:
But earlier in the thread Zeke calculated with 135T DOW so I am little bit confused what is the right figure.


Thepinkmachine and myself used landing weights in the calculations earlier in the tread. What the airline loads for catering etc is still payload, they can choose to uplift catering, cargo, fuel, or passengers with that capability. We might load three sectors worth of catering on a flight, we might tanker fuel on a flight, that is payload we have elected to carry as it often is cheaper/safer then getting at the destination. When we land however the landing weight does not know what the mass of the aircraft is comprised of, it is just looking at what fuel is needed to land with that mass after a given distance. That is why the data is presented with landing weight in the FCOM.


Thank you for expalanation!
 
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SQ32
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Re: 787 vs A350 range

Mon Jun 17, 2019 10:47 pm

Lets normalize A350 and 787 for comparison.

A359
Pax 315
Reserve fuel 5t
OEW 144
MTOW 280T
Fuel consumption 5.85t per hour

789
Pax 290
Reserve fuel 5t
OEW 129
MTOW 254T
Fuel consumption 5.4t per hour

That will make A359 a 17 hour bird. 789 will be a 16.9 hour bird.
 
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zeke
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Re: 787 vs A350 range

Mon Jun 17, 2019 10:55 pm

Mrakula wrote:
It is far from acurate but I would like to make simple comparison. TOW 253.5T fuel on board 100,6T 229 crew+pax (could be +/-25t with bags) 17:02h flight time. QF9 sometimes reach 17:30ish flight time. I do not insist I am right but I just want made easy clear comparison for not aducated people:-)

Cheers


The article says "229 passengers and crew", that is more like 23 tonnes, and also says "For the first two weeks of operations, Qantas is taking a conservative approach to the 787-9’s payload by “blocking off” (ie not selling) up to 20 passenger seats to give the aircraft a comfortable margin to ensure it can reach London without a tech stop diversion (prevailing winds mean the London-Perth sector faces fewer operational restrictions)"

So they would be taking 10% less catering, less LD3s for luggage etc.,

Mrakula wrote:

Thank you for explanation!


Boeing avoids this confusion by only listing OEW+PAYLOAD on their Y axis, what you chooses for a DOW is up to you. Where Airbus list the actual payload assuming a DOW. What people forget is the published maximum spec payload for the A350-900 is over 60 tonnes, but they already have used 6 tonnes of that when they show 54 tonnes and have a note on the chart to say for "TYPICAL INTERNATIONAL FLIGHT PROFILE 95 kg PER PASSENGER INCLUDING BAGGAGE BASIC CONFIGURATION WITH CREW REST COMPARTMENTS AND OTHER OPTIONAL FEATURES"
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
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Stitch
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Re: 787 vs A350 range

Mon Jun 17, 2019 11:18 pm

thepinkmachine said 25,000kg was the average payload for the QF flights between PER and LHR as he noted that was when the 787-9 generally becomes Fuel Volume Limited at MTOW. He noted westbound ZFWs were in the 157,000kg range with eastbound closer to 154,000kg.
 
strfyr51
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Re: 787 vs A350 range

Tue Jun 18, 2019 12:16 am

Mrakula wrote:
Mrakula wrote:
If you look at QF9 789 can lift 25t payload to around 17-17:30h.


How do you get that, you can tell the payload by looking at a photograph ? Great big neon sign on the side saying what they have onboard ?


Just like that:-) according to that artical https://australianaviation.com.au/2018/ ... in-london/

It is far from acurate but I would like to make simple comparison. TOW 253.5T fuel on board 100,6T 229 crew+pax (could be +/-25t with bags) 17:02h flight time. QF9 sometimes reach 17:30ish flight time. I do not insist I am right but I just want made easy clear comparison for not aducated people:-)

Cheers[/quote]
Unless you can actually POST a completed weight and Balance sheet for a Live flight?? Then all of this is Academic because the load sheet will give us the OEW of the airplane The Uplifted baggage and any cargo, the Fuel uplift and Passengers by compartments! All of this posted Range stuff is for salesmen. and tells us Nothing.
 
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zeke
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Re: 787 vs A350 range

Tue Jun 18, 2019 12:49 am

Stitch wrote:
thepinkmachine said 25,000kg was the average payload for the QF flights between PER and LHR as he noted that was when the 787-9 generally becomes Fuel Volume Limited at MTOW. He noted westbound ZFWs were in the 157,000kg range with eastbound closer to 154,000kg.


He doesn't work for QF, based in Europe. He "chose 25T payload because I could read it straight from the table".

Earlier in the thread Whatsaptudo said

"Tonight’s QF9 has a flight time of 16:54 with a flight fuel burn of exactly 91.0. Take off weight is 249.3/ 254.0, and it arrives with 4.5T of fuel. Carrying 210 POB so 26 empty seats all of which are in economy."

"There is No ESAD on the plan, but the Contingency fuel is 1.2. It’s 10% up to a maximum of 1.2, but that is considered to be burnt in the Min fuel required over destination. The actual Min required fuel is 95.1, but the “build up” to get them there with 70 minutes is 95.8. Final reserve is 1.9, with the approach and Arrival allowance. Min required over destination is 2.6 but QF policy is a minimum of 70 minutes hence the 4.5. The distance on the plan is 8082nm with an average overall wind of 242/20kts with an average component of 7 knots of headwind. That’s an average of the entire 17hrs

In QF we don’t carry alternates if the weather doesn’t require it, but as you can see, contrary to popular belief, we never arrive anywhere with min fuel."

"By comparison the QF10 is 15:56 for 84.8. 4.7 over destination. Distance 7957 with an average overall component of 16kts tailwind.

ZFW of the QF9 153.8
ZFW of the QF10 157.0

Both carrying about the same Pax load but the QF10 has about 3t more in the holds."
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
xwb565
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Re: 787 vs A350 range

Wed Jun 19, 2019 3:16 pm

From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.
 
Eyad89
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Re: 787 vs A350 range

Thu Jun 20, 2019 5:41 am

xwb565 wrote:
From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.



And of course, flying lighter means the needed thrust is lower, and hence less fuel is burned.

This plane probably had a TOW of 210-215t.
 
h1fl1er
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Re: 787 vs A350 range

Thu Jun 20, 2019 2:14 pm

xwb565 wrote:
From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.


it was the lower payload that reduced the fuel burn

however, 20t over 9.5hrs? the 789 returns 5.4/hr fully loaded on ULH
 
thepinkmachine
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Re: 787 vs A350 range

Thu Jun 20, 2019 2:21 pm

zeke wrote:
ZFW of the QF9 153.8
ZFW of the QF10 157.0

Both carrying about the same Pax load but the QF10 has about 3t more in the holds."


That would mean payload of ~26T for QF9 and ~29T for QF10. Looks like my assumption of 25T was slightly conservative.
"Tell my wife I am trawling Atlantis - and I still have my hands on the wheel…"
 
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AECM
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Re: 787 vs A350 range

Thu Jun 20, 2019 2:27 pm

xwb565 wrote:
From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.
This was with one of the lower MSN A359? Original Sharklets?
 
xwb565
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Re: 787 vs A350 range

Thu Jun 20, 2019 5:17 pm

AECM wrote:
xwb565 wrote:
From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.
This was with one of the lower MSN A359? Original Sharklets?


Not sure- don't have the msn. The fuel delta between the newer and older msn's should grow with higher payloads one would think.
 
tommy1808
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Re: 787 vs A350 range

Fri Jun 21, 2019 6:51 am

h1fl1er wrote:
xwb565 wrote:
From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.


it was the lower payload that reduced the fuel burn

however, 20t over 9.5hrs? the 789 returns 5.4/hr fully loaded on ULH


with the benefit of using the optimum climb profile each and every time and able to pick everything at its optimum vs. a flight where you don´t know any of those things....

best regards
Thomas
This Singature is a safe space......
 
gloom
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Re: 787 vs A350 range

Fri Jun 21, 2019 7:24 am

h1fl1er wrote:
however, 20t over 9.5hrs? the 789 returns 5.4/hr fully loaded on ULH


Do us a favor and go back over this thread.
At Ma .85 TAS is more or less 500kts. Range over 5000 is more or less 10hrs. Payload 40t, DOW 135t, ZFW 175, fuel required 56.3t. TOW 231.3t. Average: 5.63 t/hr.

Not even close to 5.4, not even close to MTOW.

For your info: it's based on thepinkmachine data, 787 driver.

But those a.net myths, you know.

Cheers,
Adam

PS Not quite sure reserves were included - probably not, so math stands. In real world, it would be even more since reserve fuel (extra weight) would increase fuel flow.
 
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MoKa777
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Re: 787 vs A350 range

Fri Jun 21, 2019 8:09 am

gloom wrote:
Do us a favor and go back over this thread.
At Ma .85 TAS is more or less 500kts. Range over 5000 is more or less 10hrs. Payload 40t, DOW 135t, ZFW 175, fuel required 56.3t. TOW 231.3t. Average: 5.63 t/hr.

Not even close to 5.4, not even close to MTOW.

For your info: it's based on thepinkmachine data, 787 driver.

But those a.net myths, you know.

Cheers,
Adam

PS Not quite sure reserves were included - probably not, so math stands. In real world, it would be even more since reserve fuel (extra weight) would increase fuel flow.


We need to stop feeding certain members who are hellbent on derailing the discussion and hopefully this thread can stop going around in circles...
Never be proud. Always be grateful.
 
flipdewaf
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Re: 787 vs A350 range

Fri Jun 21, 2019 8:25 am

gloom wrote:
h1fl1er wrote:
however, 20t over 9.5hrs? the 789 returns 5.4/hr fully loaded on ULH


Do us a favor and go back over this thread.
At Ma .85 TAS is more or less 500kts. Range over 5000 is more or less 10hrs. Payload 40t, DOW 135t, ZFW 175, fuel required 56.3t. TOW 231.3t. Average: 5.63 t/hr.

Not even close to 5.4, not even close to MTOW.

For your info: it's based on thepinkmachine data, 787 driver.

But those a.net myths, you know.

Cheers,
Adam

PS Not quite sure reserves were included - probably not, so math stands. In real world, it would be even more since reserve fuel (extra weight) would increase fuel flow.

Using the publicly available data from the qf9 thread it can be seen that over 16:54 the 789 used 91t of fuel giving 5.384t/hr on ULH.

h1fl1er however should not imply that ULH is the worst for fuel burn rate as this is not the type of flight that would show highest fuel burn rates.

The A350 and 787 burn about the same amount of fuel when at the same weights (A359 slightly less in-fact) however the a359 has a higher empty weight so.....

Fred


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zeke
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Re: 787 vs A350 range

Fri Jun 21, 2019 8:50 am

xwb565 wrote:
From a lightly loaded a350 - 20t payload, 9.5hr trip, avg fuel burn only 5.1t per hour. What a difference getting higher sooner makes.


You wouldn't buy an A350 for that, that is an A321XLR profile. Probably a seasonal load one way.

thepinkmachine wrote:
That would mean payload of ~26T for QF9 and ~29T for QF10. Looks like my assumption of 25T was slightly conservative.


I think it all depends on the headwinds, on the ppube thread one of the QF 787 pilots is saying they go 45 seats empty at times to get the range.
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Eyad89
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Re: 787 vs A350 range

Fri Jun 21, 2019 2:57 pm

h1fl1er wrote:
the 789 returns 5.4/hr fully loaded on ULH


What is fully loaded? For example, the QF9 flight that was referenced here had 210 pax onboard.
 
xwb565
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Re: 787 vs A350 range

Mon Jun 24, 2019 11:40 am

Hearing some silly fuel burn numbers for the a330-900. Neither the 787-9/10 and a359 are even close but both are faster to the tune of an hour on really long flights. The much narrower fuselage probably helps a lot.
 
thepinkmachine
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Re: 787 vs A350 range

Mon Jun 24, 2019 3:03 pm

xwb565 wrote:
Hearing some silly fuel burn numbers for the a330-900. Neither the 787-9/10 and a359 are even close but both are faster to the tune of an hour on really long flights. The much narrower fuselage probably helps a lot.


Care to share some numbers? I have flown both the 330-ceo and 787, would love to see how they compare.
"Tell my wife I am trawling Atlantis - and I still have my hands on the wheel…"
 
xwb565
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Re: 787 vs A350 range

Mon Jun 24, 2019 3:12 pm

thepinkmachine wrote:
xwb565 wrote:
Hearing some silly fuel burn numbers for the a330-900. Neither the 787-9/10 and a359 are even close but both are faster to the tune of an hour on really long flights. The much narrower fuselage probably helps a lot.


Care to share some numbers? I have flown both the 330-ceo and 787, would love to see how they compare.


4.8t-5.0t/hour depending on trip length. I am somewhat skeptical but perhaps you have a better idea.
 
thepinkmachine
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Re: 787 vs A350 range

Mon Jun 24, 2019 3:42 pm

xwb565 wrote:
4.8t-5.0t/hour depending on trip length. I am somewhat skeptical but perhaps you have a better idea.


Sounds pretty good, the classic A330 burns around 5.5-6 ton/hr, the 787 somewhat less and it flies faster.

Then again it’s all very weight dependent, we’d either need FCOM data, or at least some data of an A33N real world trip numbers (fuel, time, ZFW) to make any sensible comparison.

Having seen the A33N sales pick up lately, it must have proven itself a viable option...
"Tell my wife I am trawling Atlantis - and I still have my hands on the wheel…"
 
Eyad89
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Re: 787 vs A350 range

Wed Jun 26, 2019 10:38 am

xwb565 wrote:
4.8t-5.0t/hour depending on trip length. I am somewhat skeptical but perhaps you have a better idea.


thepinkmachine wrote:

Sounds pretty good, the classic A330 burns around 5.5-6 ton/hr, the 787 somewhat less and it flies faster.



Since Airbus promised a 12% fuel burn advantage over the A330ceo, those 4.8-5.0 t/hr figures sound about right.
 
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AECM
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Re: 787 vs A350 range

Mon Jul 22, 2019 12:53 pm

xwb565 wrote:
thepinkmachine wrote:
xwb565 wrote:
Hearing some silly fuel burn numbers for the a330-900. Neither the 787-9/10 and a359 are even close but both are faster to the tune of an hour on really long flights. The much narrower fuselage probably helps a lot.


Care to share some numbers? I have flown both the 330-ceo and 787, would love to see how they compare.


4.8t-5.0t/hour depending on trip length. I am somewhat skeptical but perhaps you have a better idea.


Hi,

Any new figures for payload / fuel burn regarding A339 or A35K? :scratchchin: :spin:
 
WIederling
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Re: 787 vs A350 range

Sat Aug 24, 2019 9:14 am

ElroyJetson wrote:
The A359 carries more payload farther than the 789. However, unless you look at different payloads across different distances to make a blanket statement that fuel burn is essentially the same is misleading imho. That is my only point.


do you really expect massive differences or even step changes in block fuel use while reducing payload?

A350 weight is all in the wing.
Afaics you get the same kind of advantage that A330 had over 767 ( or A320 over 737NG ).
Murphy is an optimist
 
patrickjp93
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Re: 787 vs A350 range

Sun Aug 25, 2019 1:33 pm

RJMAZ wrote:
The A350-900's cabin area is half way between the 787-9 and 787-10. However lets compare the two most popular models the 787-9 to the 280T A358-900.

The A350-900 can carry 10% more payload and fly it 10% further. That is the A350-900's advantage.

The 787-9 when flying the same payload the same distance burns nearly 10% less fuel on the trip. That is the 787-9's advantage.

If you had to pick only one aircraft it would depend if you had any routes that required the extra range of the A350.

The big advantage the 787 has is what parapente pointed out. As a family it is stronger. The 787-10 gains an even bigger fuel burn efficiency advantage over the A350 models but trades significant range. The 787-8 offers a size well below the A350 family. This provides lower trip costs and allows more long thin routes to open up, routes that would struggle to fill a 787-9 or A350-900.


And, using Qantas as a case study, even if you need the range long-term for some prestige flights, you might be willing to reduce pax and revenue short-term to get the range out of the smaller craft because, as we all know, airframes get re-engined eventually. The whole world is (I think rightly) convinced the A350 NEO will have EIS with the Trent Ultrafan in the late 2025-2026 timeframe. Well, if you improve the 787's range by another 10-15%, then all of a sudden the full PAX and cargo can come back into play on the newer frames, and the older can be repurposed for dense domestic routes or new international ones where much older, heavier frames are flying.

The A330 NEO had this big of a jump over the CEO, though that came in part by using more composites.
 
WIederling
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Re: 787 vs A350 range

Sun Aug 25, 2019 1:54 pm

RJMAZ wrote:
The A350-900 can carry 10% more payload and fly it 10% further. That is the A350-900's advantage.

The 787-9 when flying the same payload the same distance burns nearly 10% less fuel on the trip. That is the 787-9's


DREAM ON.
All the hard data provided goes against that statement.
You might get there for a 500nm hop with lowish payload.

patrickjp93 wrote:
The A330 NEO had this big of a jump over the CEO, though that came in part by using more composites.


The A330 NEO gets its better performance from _NEW ENGINEs_ and _NEW WINGTIPs_
I'd be surprised if the FRP content has changed that much.
Murphy is an optimist
 
patrickjp93
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Re: 787 vs A350 range

Sun Aug 25, 2019 1:57 pm

WIederling wrote:
patrickjp93 wrote:
The A330 NEO had this big of a jump over the CEO, though that came in part by using more composites.


The A330 NEO gets its better performance from _NEW ENGINEs_ and _NEW WINGTIPs_
I'd be surprised if the FRP content has changed that much.


There's been a lot of composite panelling done on the A330 NEO to make the frame lighter, though yes, engines are the bulk of it. I'm merely speaking to the terms of fleet strategy and planning and how you can wait out innovations on a plane that's only 95% of the way there now, but will be all the way there within 15-20 years.
 
flipdewaf
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Re: 787 vs A350 range

Sun Aug 25, 2019 2:00 pm

patrickjp93 wrote:
WIederling wrote:
patrickjp93 wrote:
The A330 NEO had this big of a jump over the CEO, though that came in part by using more composites.


The A330 NEO gets its better performance from _NEW ENGINEs_ and _NEW WINGTIPs_
I'd be surprised if the FRP content has changed that much.


There's been a lot of composite panelling done on the A330 NEO to make the frame lighter
has there?

Where? And how much lighter?

Fres



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patrickjp93
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Re: 787 vs A350 range

Sun Aug 25, 2019 2:10 pm

flipdewaf wrote:
patrickjp93 wrote:

There's been a lot of composite panelling done on the A330 NEO to make the frame lighter
has there?

Where? And how much lighter?

Fres



Sent from my iPhone using Tapatalk


https://www.compositesworld.com/news/ai ... den-flight - nacelle & engine pylon
https://www.airbus.com/aircraft/passeng ... 0-900.html - wing tips
https://www.flightradar24.com/blog/rout ... s-a330neo/ - hard stats on composite use & composition
The A330neo increases the overall use of composite materials, but maintains a 14% composite composition by weight thanks to the A330neos increased weight.
 
flipdewaf
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Re: 787 vs A350 range

Sun Aug 25, 2019 2:32 pm

patrickjp93 wrote:
flipdewaf wrote:
patrickjp93 wrote:

There's been a lot of composite panelling done on the A330 NEO to make the frame lighter
has there?

Where? And how much lighter?

Fres



Sent from my iPhone using Tapatalk


https://www.compositesworld.com/news/ai ... den-flight - nacelle & engine pylon
https://www.airbus.com/aircraft/passeng ... 0-900.html - wing tips
https://www.flightradar24.com/blog/rout ... s-a330neo/ - hard stats on composite use & composition
The A330neo increases the overall use of composite materials, but maintains a 14% composite composition by weight thanks to the A330neos increased weight.

Lol, so new panels on a newly required pylon and the brand new wing tips are hardly what I’d call “a lot of composite panelling” but hey, if your definition pedals your agenda better more power to you!

Fred


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patrickjp93
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Re: 787 vs A350 range

Sun Aug 25, 2019 2:34 pm

flipdewaf wrote:
patrickjp93 wrote:
flipdewaf wrote:
has there?

Where? And how much lighter?

Fres



Sent from my iPhone using Tapatalk


https://www.compositesworld.com/news/ai ... den-flight - nacelle & engine pylon
https://www.airbus.com/aircraft/passeng ... 0-900.html - wing tips
https://www.flightradar24.com/blog/rout ... s-a330neo/ - hard stats on composite use & composition
The A330neo increases the overall use of composite materials, but maintains a 14% composite composition by weight thanks to the A330neos increased weight.

Lol, so new panels on a newly required pylon and the brand new wing tips are hardly what I’d call “a lot of composite panelling” but hey, if your definition pedals your agenda better more power to you!

Fred


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Considering the engines were much heavier on the NEO, that's several tonnes of aluminum replaced by composites to keep the same percentage of composites by weight.
 
flipdewaf
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Re: 787 vs A350 range

Sun Aug 25, 2019 2:52 pm

patrickjp93 wrote:
flipdewaf wrote:
patrickjp93 wrote:

Lol, so new panels on a newly required pylon and the brand new wing tips are hardly what I’d call “a lot of composite panelling” but hey, if your definition pedals your agenda better more power to you!

Fred


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Considering the engines were much heavier on the NEO, that's several tonnes of aluminum replaced by composites to keep the same percentage of composites by weight.

Several tonnes? Really?

What percentage of the engine is composite? I used to make composites for Jet engines, there were lots of bits.

Fred


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patrickjp93
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Re: 787 vs A350 range

Sun Aug 25, 2019 3:23 pm

flipdewaf wrote:
patrickjp93 wrote:
flipdewaf wrote:
Lol, so new panels on a newly required pylon and the brand new wing tips are hardly what I’d call “a lot of composite panelling” but hey, if your definition pedals your agenda better more power to you!

Fred


Sent from my iPhone using Tapatalk


Considering the engines were much heavier on the NEO, that's several tonnes of aluminum replaced by composites to keep the same percentage of composites by weight.

Several tonnes? Really?

What percentage of the engine is composite? I used to make composites for Jet engines, there were lots of bits.

Fred


Sent from my iPhone using Tapatalk


Given they're Rolls Royce engines, less than 10% of the engines will be composites (not even the fan case yet if memory serves), so yes, several tonnes. RR will be moving in on composites in the next decade, but they've been stretching their conventional manufacturing as far as they can take it. Where GE is ancient with its twin-spool designs, RR is ancient with their materials, but the triple-spool design drastically cuts down on the weight needed for stator veins, so they end up being very comparable in weight, but RR is still way behind on using composites. Heck the XWB still has an all-titanium fan for crying out loud.
 
WIederling
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Re: 787 vs A350 range

Sun Aug 25, 2019 4:40 pm

patrickjp93 wrote:
Heck the XWB still has an all-titanium fan for crying out loud.


They still allow thinner profile blades. Not everything new is better. often it just is different.

GE afaics sails on blades that have a high rate of rejects during production,
require lots of manual labor
_and_ have reduced blade out requirements granted by FAA afaik.
Murphy is an optimist
 
patrickjp93
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Re: 787 vs A350 range

Sun Aug 25, 2019 5:02 pm

WIederling wrote:
patrickjp93 wrote:
Heck the XWB still has an all-titanium fan for crying out loud.


They still allow thinner profile blades. Not everything new is better. often it just is different.

GE afaics sails on blades that have a high rate of rejects during production,
require lots of manual labor
_and_ have reduced blade out requirements granted by FAA afaik.


Those blade QA issues have pretty much all been dealt with. They were ironed out over the lives of the GE-90, GEnx, PW1000G, and the CFM-LEAP. PW uses them, GE uses them, CFM uses them, and RR will finally start using composite blades with the Ultrafan, and they had been trying to do so previously. I can't speak to the amount of manual time, but I somewhat doubt that's a big issue. Heck if Mitsubishi and Boeing can 3D print entire plane wings with hollow cores, a solid blade should be a walk in the park by now.

And back to my earlier mentions on composite use in the Trent 7000, RR still doesn't even use a composite fan case afaik.

The three main players branched out in 3 different directions, and now they're starting to learn each other's moves. The GE9X I'm almost certain is GE's final conventional 2-spool engine. They've mastered the exotic ceramic composite materials for ultra hot fuel burn efficiency and carbon composite materials for skin, nacelle, and case to keep the weight down . Now it's time to pump up the efficiency either with a 3rd spool or a geared fan. PW has gotten geared fans to work very well (compressor issues aside), and they have some carbon composite parts already, but it's time to step up their game on core design. RR has the long-term experience and efficiency from running three spools, but they're nowhere yet on geared fans or exotic materials, which is what makes the Ultrafan an extremely ambitious undertaking. As for CFM, they get the materials experience from GE while having a lot of niche expertise on component geometry, particularly in the combustor.

Three spools is new, but it's better than two spools. Exotic materials are new, but definitely better on both weight and tolerances than standard Titanium construction, probably cheaper now too. Geared fans are very new and are doubtlessly superior to conventional 2 and 3-spool engine designs. Everything we're talking about here is without a doubt superior to the old way of doing things, but that's because these are top notch engineers doing what they love.
 
flipdewaf
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Re: 787 vs A350 range

Mon Aug 26, 2019 8:58 am

patrickjp93 wrote:
flipdewaf wrote:
patrickjp93 wrote:

Considering the engines were much heavier on the NEO, that's several tonnes of aluminum replaced by composites to keep the same percentage of composites by weight.

Several tonnes? Really?

What percentage of the engine is composite? I used to make composites for Jet engines, there were lots of bits.

Fred


Sent from my iPhone using Tapatalk


Given they're Rolls Royce engines, less than 10% of the engines will be composites (not even the fan case yet if memory serves), so yes, several tonnes. RR will be moving in on composites in the next decade, but they've been stretching their conventional manufacturing as far as they can take it. Where GE is ancient with its twin-spool designs, RR is ancient with their materials, but the triple-spool design drastically cuts down on the weight needed for stator veins, so they end up being very comparable in weight, but RR is still way behind on using composites. Heck the XWB still has an all-titanium fan for crying out loud.

Let’s assume 14% of a total 125t frame is composite and 2 6t engines are 10% each. That means 17.5t total composite with 1.2t of that in the engines so the airframe is 16.3t.

In the new engine that is ~1ton heavier there is still ~10% composite so a total of 1.4t in the engine for a required 17.78t total in the aircraft or 16.38 in the airframe. A whopping 80kg of composites! Just stick some hefting great wing tips and you’re there!

Fred


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patrickjp93
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Re: 787 vs A350 range

Mon Aug 26, 2019 10:46 am

flipdewaf wrote:
Let’s assume 14% of a total 125t frame is composite and 2 6t engines are 10% each. That means 17.5t total composite with 1.2t of that in the engines so the airframe is 16.3t.

In the new engine that is ~1ton heavier there is still ~10% composite so a total of 1.4t in the engine for a required 17.78t total in the aircraft or 16.38 in the airframe. A whopping 80kg of composites! Just stick some hefting great wing tips and you’re there!

Fred


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The A330-900 is also the same composite percentage by weight. And RR engines are less than 10% composites. 10 is probably high-balling them. And we don't even know if Airbus would be counting the composites in the engines to begin with, as that's a factor they can't control. But regardless, your math is still off. There's additional weight in the airframe beyond the engines, mainly from wing and wing box strengthening with Titanium. Even if 10% is spot on and Airbus includes the engines in their calculations, you're looking closer to 800kg as a lowball estimate of additional composite materials included.
 
WIederling
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Re: 787 vs A350 range

Mon Aug 26, 2019 3:33 pm

patrickjp93 wrote:
There's additional weight in the airframe beyond the engines, mainly from wing and wing box strengthening with Titanium.


Titanium?

I'd expect the machined Al parts to be slightly resized.

patching up parts with different materials is the perfect way to increase weight more than strength.
Murphy is an optimist
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