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Bambel
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Differences Between A350-900 And A350-1000

Wed Dec 02, 2015 12:10 am

Hi, i am interested in the differences between the two types and how they influence operating costs.

To my knowledge, the -1000 has

- a different engine, not only an uprated version of the -900 engine
- wing trailing edge extentions that increase wing area about 4%
- tripple axle bogeys instead of double axle
- weight optimisations like CFRP-doorframes

Anything missing?

My thoughts:

Engines: AFAIK Rolls Royce prefers to sell "power by the hour" and does that help to mitigate the lower comunality?

Wings: more unique spare parts (flaps, ..) to store?

Landing gear: is the strut the same and only the bogey different? Do airlines store landing gears as spares? If they are ordered as needed, it should make little difference wether they are identical or not?

Optimisations: i guess there are things without negative impact and others that lead to "more part numbers"?

Part of the reasoning behind EK canceling the A350 order is said to be that they didn't needed the increased capability of the revised -1000 and wanted more communality to the -900 instead. But is there realy such a big difference in operating costs?

Pure guess, but i think there is more in common between the two A350s compared to the A330 and A340 (classic)?

Thanks,
b.
 
StTim
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RE: Differences Between A350-900 And A350-1000

Thu Dec 03, 2015 10:06 am

I guess the optimisations will, where possible, actually be fed back into the 900 to improve that frame as well.
 
r2rho
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RE: Differences Between A350-900 And A350-1000

Thu Dec 03, 2015 1:30 pm

Quoting Bambel (Thread starter):
Pure guess, but i think there is more in common between the two A350s compared to the A330 and A340 (classic)?

Tough one. The A3323 and A3423 are the same aircraft, bar the completely different engines and the center LG on the A343. The A359 and A35K are slightly different aircraft, with somewhat different engines. Take your pick on which counts most.
 
astuteman
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RE: Differences Between A350-900 And A350-1000

Thu Dec 03, 2015 6:28 pm

Quoting Bambel (Thread starter):
Anything missing?

The engine isn't a different engine. It's the same engine with modifications...

Rgds
 
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LAX772LR
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 7:40 am

The A35K fuel system is different than the standard A359, in that it's the same raw capacity, but (IINM) software and plumbing limit the extent to which it can be filled. The A35K and A359ULR will be able to go max volume, the standard A359 will not.
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KarelXWB
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 10:12 am

Quoting Bambel (Thread starter):
- a different engine, not only an uprated version of the -900 engine

Just to be clear: it's not a different engine, TXWB-84 and TXWB-97 are 80% common.

Quoting Bambel (Thread starter):
But is there realy such a big difference in operating costs?

I have no idea on costs, but I do know aircraft differences are not uncommon: even the A332 and A333 are different in certain design areas. And while EK may have seen this as an issue, clearly CX and QR don't make a big deal out of it.

Quoting r2rho (Reply 2):
The A3323 and A3423 are the same aircraft, bar the completely different engines and the center LG on the A343.

A340-300 also has a different fuel system.

[Edited 2015-12-11 02:25:38]
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KarelXWB
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 10:22 am

Quoting Bambel (Thread starter):
Optimisations: i guess there are things without negative impact and others that lead to "more part numbers"?

The A350-1000 comes with optimizations. The slide below shows the primary changes versus the -900 model.

Most of these changes should find their way into the A350-900. I also want to point out that introducing optimizations is pretty common in aviation. To give two examples: the 787-9 has many different area's than the smaller 787-8, and the Trent 1000-TEN will also be significant different than the current Trent 1000 engines.

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StTim
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 10:46 am

I suppose the 350-1000 is a good place to introduce such optimizations as it allows the testing of them concurrently with the 350-1000 test cycles. They will then be avaiable to back port into the 350-900.

I also suspect there will be multiple small changes which will be introduced to improve the production process.
 
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Matt6461
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 12:27 pm

The wing skins and spars will also be strengthened/thickened for the greater MZFW bending moment created by the heavier fuselage and payload.

Ferpe did an analysis a couple of years ago showing that the A35K's fuel burn per seat was only slightly better than A359's. That wing is a bit shorter than optimal for A35K, perfect for the -900.
 
astuteman
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 4:23 pm

Quoting Matt6461 (Reply 8):
Ferpe did an analysis a couple of years ago showing that the A35K's fuel burn per seat was only slightly better than A359's. That wing is a bit shorter than optimal for A35K, perfect for the -900.

I think the 3-axle MLG is a big contributor to this. It adds a fair amount of weight IMO.

(One of the reasons why I think the push to 280t on the A359 on 2-axle MLG would make an excellent platform for an A350-1000 "lite"   )

Rgds
 
Bambel
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 7:00 pm

Thank you all for your replies!

So it seem that the differences between these sub-models are on a similar level like on other programs and it was more an EK specific issue. What did the first iteration of the -1000 that EK ordered look like? What did A change on the real -1000? Did it allready had the tripple bogey?

b.
 
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DocLightning
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 9:28 pm

Quoting KarelXWB (Reply 5):
Just to be clear: it's not a different engine, TXWB-84 and TXWB-97 are 80% common.

80% by weight or parts count? Where are most of the differences?
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Stitch
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RE: Differences Between A350-900 And A350-1000

Fri Dec 11, 2015 11:43 pm

Quoting DocLightning (Reply 11):
80% by weight or parts count? Where are most of the differences?

I'm guessing parts since "spares provisioning" is said to be impacted by the changes. As to the differences themselves, they are said to be mainly in the high-temperature core section, including changes to tip clearance control and a shroudless blade system.
 
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Matt6461
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RE: Differences Between A350-900 And A350-1000

Sat Dec 12, 2015 2:20 am

Quoting astuteman (Reply 9):
A359 on 2-axle MLG would make an excellent platform for an A350-1000 "lite"

Interesting idea, first I've heard of it. Allow Airbus to have its high-capability A35K and eat its efficiency cake too. If only they could push it for the EK regional order...

Mmmmmmm efficiency cake
 
DTWPurserBoy
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Re: Differences Between A350-900 And A350-1000

Sat Aug 20, 2016 9:42 pm

The six wheel main bogey spreads the weight out more evenly for tarmac and runway use. Reminds me of when McDonnell Douglas added the center gear to the DC-10-30/40 series.
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WIederling
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Re: Differences Between A350-900 And A350-1000

Sun Aug 21, 2016 10:23 am

DTWPurserBoy wrote:
The six wheel main bogey spreads the weight out more evenly for tarmac and runway use. Reminds me of when McDonnell Douglas added the center gear to the DC-10-30/40 series.


the "splayed out" twin axle bogie of the -900 spanning a larger load area
already allows more MTOW ( now 280t) than the narrower one on the 787 ( 250+t).
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DocLightning
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Re: Differences Between A350-900 And A350-1000

Mon Aug 22, 2016 12:03 am

WIederling wrote:

the "splayed out" twin axle bogie of the -900 spanning a larger load area
already allows more MTOW ( now 280t) than the narrower one on the 787 ( 250+t).


It's about the contact patches, though, not the area over which the weight is splayed out.
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Starlionblue
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Re: Differences Between A350-900 And A350-1000

Mon Aug 22, 2016 3:15 am

DocLightning wrote:
WIederling wrote:

the "splayed out" twin axle bogie of the -900 spanning a larger load area
already allows more MTOW ( now 280t) than the narrower one on the 787 ( 250+t).


It's about the contact patches, though, not the area over which the weight is splayed out.


It is about both. The pavement has a limit to how much you can plonk down on a contact patch (effectively a single point) and there's also a limit on how much you can put down on an area. Spreading the wheels out does help in the latter case.
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OldAeroGuy
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Re: Differences Between A350-900 And A350-1000

Wed Aug 24, 2016 1:18 pm

Starlionblue wrote:
DocLightning wrote:
WIederling wrote:

the "splayed out" twin axle bogie of the -900 spanning a larger load area
already allows more MTOW ( now 280t) than the narrower one on the 787 ( 250+t).


It's about the contact patches, though, not the area over which the weight is splayed out.


It is about both. The pavement has a limit to how much you can plonk down on a contact patch (effectively a single point) and there's also a limit on how much you can put down on an area. Spreading the wheels out does help in the latter case.


It also depends on if the pavement is flexible (asphalt) or rigid (concrete). Spreading out the load will help on rigid pavement but will not help on individual wheel loads on flexible pavement.
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rbavfan
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Re: RE: Differences Between A350-900 And A350-1000

Thu Nov 24, 2016 10:15 am

r2rho wrote:
Quoting Bambel (Thread starter): Pure guess, but i think there is more in common between the two A350s compared to the A330 and A340 (classic)?
Tough one. The A3323 and A3423 are the same aircraft, bar the completely different engines and the center LG on the A343. The A359 and A35K are slightly different aircraft, with somewhat different engines. Take your pick on which counts most.



Actually the A330-200 & A340-200 are different lengths. The A330-300 & A340-300 are the same fuselage length.
 
WIederling
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Re: RE: Differences Between A350-900 And A350-1000

Thu Nov 24, 2016 1:38 pm

rbavfan wrote:
Actually the A330-200 & A340-200 are different lengths. The A330-300 & A340-300 are the same fuselage length.


Larger fin that extends beyond the tailcone.

( Just like the KC-46 which is longer for the overhanging stinger of the boom.)
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speedygonzales
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Re: RE: Differences Between A350-900 And A350-1000

Thu Nov 24, 2016 3:43 pm

WIederling wrote:
rbavfan wrote:
Actually the A330-200 & A340-200 are different lengths. The A330-300 & A340-300 are the same fuselage length.


Larger fin that extends beyond the tailcone.

( Just like the KC-46 which is longer for the overhanging stinger of the boom.)

No, the A330-200 fuselage is about 1m shorter than the A340-200 fuselage, all of it ahead of the wing AFAICT.
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WIederling
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Re: RE: Differences Between A350-900 And A350-1000

Thu Nov 24, 2016 5:10 pm

speedygonzales wrote:
WIederling wrote:
rbavfan wrote:
Actually the A330-200 & A340-200 are different lengths. The A330-300 & A340-300 are the same fuselage length.


Larger fin that extends beyond the tailcone.

( Just like the KC-46 which is longer for the overhanging stinger of the boom.)

No, the A330-200 fuselage is about 1m shorter than the A340-200 fuselage, all of it ahead of the wing AFAICT.


You are right. :-) the fuselage is 1.06 m shorter at the front. radom nose to MLG center
and this reflects directly into the fuselage length.
but overall the length is only .57m shorter. i.e. the 330's horz. stab extends another 49 cm?
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wingscrubber
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Re: Differences Between A350-900 And A350-1000

Fri Dec 16, 2016 4:07 pm

MLG on -900 & -1000 are completely different - from different manufacturers. -900 has the messier-dowty gear, -1000 has the goodrich gear. All the actuators, doors are unique to the gear, not interchangeable. One difference between them is, word has it -1000 has a pneumatically pressurised bogie pitch trimmer/truck positioner like the old A300/A310, whereas -900's is hydraulic.
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WIederling
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 10:13 am

LAX772LR wrote:
The A35K fuel system is different than the standard A359, in that it's the same raw capacity, but (IINM) software and plumbing limit the extent to which it can be filled. The A35K and A359ULR will be able to go max volume, the standard A359 will not.


Three distinct fuel capacity sizes: 139kl ( -900), 156kl ( -1000), 165kl ( ULR).
Physically available volume is at least 165kl.
Beyond small plumbing changes ( and probably adapting the inerting system to the higher capacity )
volume changes are a software switch.
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MPadhi
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 12:42 pm

WIederling wrote:
LAX772LR wrote:
The A35K fuel system is different than the standard A359, in that it's the same raw capacity, but (IINM) software and plumbing limit the extent to which it can be filled. The A35K and A359ULR will be able to go max volume, the standard A359 will not.


Three distinct fuel capacity sizes: 139kl ( -900), 156kl ( -1000), 165kl ( ULR).
Physically available volume is at least 165kl.
Beyond small plumbing changes ( and probably adapting the inerting system to the higher capacity )
volume changes are a software switch.


If they have the same physical volume, what's the rationale for not allowing all planes to use the full volume?
 
WIederling
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 1:56 pm

MPadhi wrote:
If they have the same physical volume, what's the rationale for not allowing all planes to use the full volume?


No need for so much extra fuel and the inerting system needs less capacity?
( then you probably have to control how much goes into the wing tanks and what goes into the center tank ( that extends into the wings!)
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LAX772LR
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 7:50 pm

WIederling wrote:
Beyond small plumbing changes ( and probably adapting the inerting system to the higher capacity )
volume changes are a software switch.

It's a bit more involved than that: someone posted the full extent of modifications, and there's certainly a more extensive physical component to the difference, than many people here initially figured.

Plumbing/ducting and inerting differences, as you mentioned; but also censors, pumps (i.e. weight), modified ejection/dumping, etc. But it's all supposedly reversible, so there's that.

I do wonder if it's mostly for naught, as I wouldn't be surprised to see SQ end up being the only significant airline that actually takes A359ULRs..... for anyone else: why bother, once the 280T standard-A359 enters service only some months later?



MPadhi wrote:
If they have the same physical volume, what's the rationale for not allowing all planes to use the full volume?

What'd be the point? They wouldn't be able to effectively utilize it.

The A359ULR is what it is, because it shorts the hell outta the ZFW, in order to be able to carry the amount of fuel that it does. It's still the same MTOW as the 280T standard A359s that will follow it.

That doesn't sound "bad" until you realize that it effectively limits the pax cabin capacity by about 100 seats-- which is why all the SQ configs we're hearing tales of, are never over 170-180 seats or so. There are 737s with more capacity. (And before anyone gets their knickers in a twist, yes I'm aware of the premium ratio)

That's also probably why (despite their lip service) no other airline has touched the thing. Notably the ME3. PR was supposedly going to, until they realized that they could short seats on a 278T standard A359, and lose less money flying that from MNL to the US east coast. Pretty sure most other Asian carriers will arrive at the same conclusion.
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KarelXWB
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 8:59 pm

MPadhi wrote:
If they have the same physical volume, what's the rationale for not allowing all planes to use the full volume?


Because it isn't certified.

The A330-300 always had the center fuel tank installed, but it wasn't activated until the 242t model was certified.
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MPadhi
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 10:04 pm

WIederling wrote:
MPadhi wrote:
If they have the same physical volume, what's the rationale for not allowing all planes to use the full volume?


No need for so much extra fuel and the inerting system needs less capacity?
( then you probably have to control how much goes into the wing tanks and what goes into the center tank ( that extends into the wings!)
http://4.bp.blogspot.com/-hukRuL5lDYs/V ... /image.jpg


Thanks for the diagram :)

LAX772LR wrote:
WIederling wrote:
Beyond small plumbing changes ( and probably adapting the inerting system to the higher capacity )
volume changes are a software switch.

It's a bit more involved than that: someone posted the full extent of modifications, and there's certainly a more extensive physical component to the difference, than many people here initially figured.

Plumbing/ducting and inerting differences, as you mentioned; but also censors, pumps (i.e. weight), modified ejection/dumping, etc. But it's all supposedly reversible, so there's that.


Have you by chance got a link to the full description of the differences?

LAX772LR wrote:
The A359ULR is what it is, because it shorts the hell outta the ZFW, in order to be able to carry the amount of fuel that it does. It's still the same MTOW as the 280T standard A359s that will follow it.


So if I understand correctly, you're saying that this makes the plane heavier whilst not increasing its max payload, so most carriers are just choosing to reduce the payload on the standard A350?
 
WIederling
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 11:06 pm

LAX772LR wrote:
The A359ULR is what it is, because it shorts the hell outta the ZFW, in order to be able to carry the amount of fuel that it does. It's still the same MTOW as the 280T standard A359s that will follow it.


If you look at the payload range curve for the regular 275t A359 and paint in the MTOW increase you will see that you need more fuel otherwise you run into the fuel limit for more range ( derates payload at about twice the amount you work with in the payload for fuel swap area.)

Then my guess is the ULR concept was drawn up at a time when the base A359 was still at the original 268t MTOW.
After that ( creation of the ULR ) we saw MTOW uprate for the transient overweight ( to 275t) and then the further upgrade to 280t for the future.
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Stitch
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Re: RE: Differences Between A350-900 And A350-1000

Sat Dec 17, 2016 11:52 pm

MPadhi wrote:
So if I understand correctly, you're saying that this makes the plane heavier whilst not increasing its max payload, so most carriers are just choosing to reduce the payload on the standard A350?


Actually the plane will probably end up being lighter due to the much lower seat count. It's just that you are making a "hard" trade of payload weight for fuel weight - you limit the maximum payload you can ever take to maximize the fuel load you can take.

With the non-ULR models, you will trade payload weight for fuel weight on longer missions, but you still have the full payload weight available for shorter missions. So most airlines will likely prefer that flexibility.
 
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Re: RE: Differences Between A350-900 And A350-1000

Sun Dec 18, 2016 12:02 am

LAX772LR wrote:
The A359ULR is what it is, because it shorts the hell outta the ZFW


Was there ever any mention about the MZFW of the A359-ULR ?
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Stitch
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Re: RE: Differences Between A350-900 And A350-1000

Sun Dec 18, 2016 12:08 am

WIederling wrote:
LAX772LR wrote:
The A359ULR is what it is, because it shorts the hell outta the ZFW


Was there ever any mention about the MZFW of the A359-ULR ?


Nothing official, but I believe it was Leeham.net who said it could be in the neighborhood of 190.000kg.
 
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Re: RE: Differences Between A350-900 And A350-1000

Sun Dec 18, 2016 2:04 am

Stitch wrote:
With the non-ULR models, you will trade payload weight for fuel weight on longer missions, but you still have the full payload weight available for shorter missions. So most airlines will likely prefer that flexibility.

Especially since that flexibility is sufficient for transpacs all the way from SE Asia carrying more or less a standard cabin's payload even now... imagine when they add five more available tons.
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Okcflyer
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Re: Differences Between A350-900 And A350-1000

Mon Dec 19, 2016 3:33 am

Why does the MZFW drop so much for the ULR? If the additional component changes don't significantly change OEW, why such a substantial drop for MZFW? From an airframe stress perspective, it's not making much sense to me?

Would a belly aux tank been a cheaper, easier, and more flexible solution fit in the standard forthcoming 280T frame? Such tank (and weight) shouldn't carry the same level of loading restrictions when not needing to be used, right?

Are we sure there is no MZFW change the non-ULH 280T model?
 
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Re: Differences Between A350-900 And A350-1000

Mon Dec 19, 2016 8:51 am

Okcflyer wrote:
Would a belly aux tank been a cheaper, easier, and more flexible solution fit in the standard forthcoming 280T frame? Such tank (and weight) shouldn't carry the same level of loading restrictions when not needing to be used, right?


190t MZFW is 1..2t less than the 268t MTOW ( 172t MZFW ) version the A359 started out with.
195t MZWF is linked to the 275t MTOW currently available version.
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What makes you think that using more of the existing tankage associated with zero extra mass
is less efficient than adding in dedicated Aux Tanks ( the A320 ones have considerable dead weight?)
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Matt6461
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Re: Differences Between A350-900 And A350-1000

Tue Dec 20, 2016 5:12 am

Okcflyer wrote:
Why does the MZFW drop so much for the ULR? If the additional component changes don't significantly change OEW, why such a substantial drop for MZFW? From an airframe stress perspective, it's not making much sense to me?


I had/have the same impression. Here's the only way I can make sense of it:
-The extra fuel carried in body-tanks acts like payload for the purposes of computing the max structural stress condition
-One would think, however, that laws would require the body-tanked fuel to be burned first, so that the MZFW bending moment (usually the critical stress condition) wouldn't be altered for the ULR
-For some reason, this is not the case: even with max fuel in the wings providing bending relief, a worst-case-scenario gust with full body and wing tanks would exceed structural stress limits unless payload is reduced

I still can't make intuitive sense of how that math works out - the bending relief provided by full wing tanks would seem to counteract more weight in body tanks (again, assuming the body-tanked fuel is burned first by law).
 
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AA777223
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Re: Differences Between A350-900 And A350-1000

Tue Dec 20, 2016 3:52 pm

This may sound stupid, but it's longer... :-)
A318/19/20/21, A300, A332/3, A343/6, A388, L1011, DC-9, DC-10, MD-11, MD-80, B722, B732/3/4/5/7/8/9, B743/4/4M, B752/3, B762/3/4, B772/E/W, B788/9, F-100, CRJ-200/700/900, ERJ-135/145/175/190, DH-8, ATR-72, DO-328, BAE-146
 
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Stitch
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Re: Differences Between A350-900 And A350-1000

Wed Dec 21, 2016 4:40 pm

Okcflyer wrote:
Why does the MZFW drop so much for the ULR? If the additional component changes don't significantly change OEW, why such a substantial drop for MZFW? From an airframe stress perspective, it's not making much sense to me?


I am going to hazard a guess that it is because you're optimizing the frame to haul fuel, not passengers and cargo.


Okcflyer wrote:
Are we sure there is no MZFW change the non-ULH 280T model?


We won't know for sure until Airbus updates the ACAP with the 280,000kg WV charts for the A350-900 and A350-900ULR.
 
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Re: RE: Differences Between A350-900 And A350-1000

Wed Dec 21, 2016 5:08 pm

Bambel wrote:
Thank you all for your replies!

So it seem that the differences between these sub-models are on a similar level like on other programs and it was more an EK specific issue. What did the first iteration of the -1000 that EK ordered look like? What did A change on the real -1000? Did it allready had the tripple bogey?

b.

The EK explanation (for what it's worth) was that the first iteration of the A35K had an equivalence to the 773(non-ER). Engine-wise it would have been a straight throttle-push of the XWB-84 to power it. As the aircraft was developed and the variant engine specified together with changes to weights and capability, EK declared that it was no longer the high compatability regional solution they had ordered and this was part of the decision to cancel the whole order and put it back out to bidding. Just how the cancellation was done with Airbus is another story.

Others have concluded that there were other factors at play here. Namely delivery times and prices. Emirates have a large order book of other aircraft to keep busy and the subsequent orders for aircraft in this sector haven't happened yet.
 
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Stitch
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Re: RE: Differences Between A350-900 And A350-1000

Wed Dec 21, 2016 5:25 pm

Channex757 wrote:
The EK explanation (for what it's worth) was that the first iteration of the A35K had an equivalence to the 773(non-ER). Engine-wise it would have been a straight throttle-push of the XWB-84 to power it. As the aircraft was developed and the variant engine specified together with changes to weights and capability, EK declared that it was no longer the high compatability regional solution they had ordered and this was part of the decision to cancel the whole order and put it back out to bidding. Just how the cancellation was done with Airbus is another story.

Others have concluded that there were other factors at play here. Namely delivery times and prices. Emirates have a large order book of other aircraft to keep busy and the subsequent orders for aircraft in this sector haven't happened yet.


EK wanted Boeing to make a larger 777 - the "777-400ER" as they called it. I could see them ordering 20 A350-1000 as a "motivator" to get Boeing to move forward on such a program. The original A350-1000 was a solid 777-300A replacement for them (just lacking the passenger capacity) and allowed them to "super-size" their 777-200s / 777-200ERs - the 20-frame order would have provided them with the capacity they needed to replace those planes.

If Boeing had not launched the larger 777, I fully expect they would have ordered significantly more A350-1000s as the improvements to the type would have made it more desirable as a 777-300ER replacement (even if it lacked the outright capacity).
 
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Channex757
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Re: RE: Differences Between A350-900 And A350-1000

Wed Dec 21, 2016 9:05 pm

Stitch wrote:
Channex757 wrote:
The EK explanation (for what it's worth) was that the first iteration of the A35K had an equivalence to the 773(non-ER). Engine-wise it would have been a straight throttle-push of the XWB-84 to power it. As the aircraft was developed and the variant engine specified together with changes to weights and capability, EK declared that it was no longer the high compatability regional solution they had ordered and this was part of the decision to cancel the whole order and put it back out to bidding. Just how the cancellation was done with Airbus is another story.

Others have concluded that there were other factors at play here. Namely delivery times and prices. Emirates have a large order book of other aircraft to keep busy and the subsequent orders for aircraft in this sector haven't happened yet.


EK wanted Boeing to make a larger 777 - the "777-400ER" as they called it. I could see them ordering 20 A350-1000 as a "motivator" to get Boeing to move forward on such a program. The original A350-1000 was a solid 777-300A replacement for them (just lacking the passenger capacity) and allowed them to "super-size" their 777-200s / 777-200ERs - the 20-frame order would have provided them with the capacity they needed to replace those planes.

If Boeing had not launched the larger 777, I fully expect they would have ordered significantly more A350-1000s as the improvements to the type would have made it more desirable as a 777-300ER replacement (even if it lacked the outright capacity).

I think what can be distilled form all this is that EK would have been happy with the plane as sold, but the timing was just all wrong for them and the changes made it into something not right for their market. What they needed was a 773-sized CASM killer that could do the Indian subcontinent and close Asian markets. Did Airbus also crank the price up to EK? That we will never really know.

The 777(non-GE) fleet at EK and the A332 are all either leaving or gone now. The original A35K would have been rolling out to replace them before the delays and engine changes. That's another big contract fail.

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