SteelChair
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Re: United eyes A330-800 for fleet replacement

Sat Mar 03, 2018 6:01 pm

The thread has been polluted by belief of manufacturerers performance and weight claims. The 112 ton OEW 788 is about as common as a carrier pigeon. If the 788 were a viable option for a 767 replacement, there would be no need for MOM.

An aggressively re-worked and lightened 783 might be an option...but is probably not likely imho. Downsized airplanes usually don't work out...the 747SP, L1011-500, A310, and A318 come to mind. Early generation variants normally get marginalized fairly quickly, think 727-100, 737-100, A319, B767-200. So its hard to imagine a 783 being competitive just as the 788 gets squeezed out by its bigger brothers.

The unspoken part of this discussion is what the airlines are willing to pay. They haven't been willing to pay for new tech in the narrowbody segment. Witness the dearth of CSeries orders vs large number of orders for re-engined 320 and craptastic 737 derivatives. What evidence is there to make a manufacturer believe that the airlines will pay the necessary sum for an all new wide body? Especially the airlines in western Europe and the USA that are being squeezed by LCCs on the one hand and by the state supported ME3 on the other.

So we're left with the 332 imho. It's not only a pretty good airplane, it's a comparatively low cost/low risk option that is available soon and has training cost efficiencies for those airlines already operating 320s and 330s. Granted this goes against my earlier comment about smaller derivatives not being competitive, but what better option is there?
 
trex8
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Re: United eyes A330-800 for fleet replacement

Sat Mar 03, 2018 6:03 pm

ro1960 wrote:
trex8 wrote:
Polot wrote:
Its mentioned here because UA mentions it, even if you want to pretend that they don't/are not actually considering it. You realize that UA may decide to just work with what they have, maybe pick up a few more used 767s, and wait right? It is not like UA could get the A338 before ~2020 anyways.

A338 is supposed to EIS 2019, originally they said a year after A339 which I think they are still hoping is still first half 2018 or at least Q3 per TAP, no idea how many A330ceo/neo slots are free for 2019.
But then there may be 6 slots free soon if certain rumors are true!


The first two A330neo for TP just rolled out of the paint shop. Any idea about the EIS?

https://worldairlinenews.com/2018/03/03/a-double-roll-out-for-the-first-airbus-a330neo-operator-tap-air-portugal/

Q3??
The airline is due to receive its first aircraft around the middle of next year, although entry into service could slip into the third quarter. https://blueswandaily.com/tap-air-portu ... ul-vision/
 
B777LRF
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Re: United eyes A330-800 for fleet replacement

Sat Mar 03, 2018 6:41 pm

SonomaFlyer wrote:
The 788 has far too much range vis a vie the 767. They don't need a 16 hour plane to perform an 8-9 hour mission which is primarily what the 767 does (though many segments are shorter).


It might not be an optimised solution, but QR are running a large fleet of 787-8s on DOH-Europe services. BA are dispatching 787-9s across the pond en masse. Those are all 5-9 hour flights, and we don't hear anybody complaining about the economics on those sectors.
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LXwing
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Re: United eyes A330-800 for fleet replacement

Sat Mar 03, 2018 7:25 pm

The first TP A330neo are now scheduled for delivery in September, 3 of them apparently, with a total of 7 deliveries planned until year end. EIS should be soon after depending mostly on how fast local certification is achieved.
 
WIederling
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 9:19 am

SteelChair wrote:
Downsized airplanes usually don't work out...the 747SP, L1011-500, A310, and A318 come to mind.


Little nit: the A310 is not really a shrink of the A300 even if it is the same fuselage and cross section only shorter.

The A310 was exactly the kind of MoM step that is asked for, though in a different direction.
The A310 got a brand new fully supercritical from scratch wing.
I don' think that even the center wing box is the same.
Murphy is an optimist
 
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SQ789
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 12:03 pm

Wow interesting, I bet these will result the A350 order cancellation?
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WIederling
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 12:09 pm

SQ789 wrote:
Wow interesting, I bet these will result the A350 order cancellation?


reflexive some?

A330 or MoM would be a different size slot than "A359" wouldn't it?

Image
src: https://pbs.twimg.com/media/DXJfUmnW4AAra_y.jpg
OT from the A350 production thread.
Murphy is an optimist
 
rheinwaldner
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 12:52 pm

RJMAZ wrote:
The 787-8 is actually the smallest and lightest widebody even when compared to the A330-800.
The 787-8 is lower in ever metric:
Length: 56.7m vs 58.8m
Wing span: 60.1m vs 64m
Wing area: 377m2 vs 380m2
Empty weight: 119T vs 124T
Max takeoff weight: 227T vs 242T
Fuel capacity: 126,000L vs 139,000L
Range: 7355nm vs 7500nm

The 787-8 is closer to the 767-300ER than the A330-800.

Did you on purpose or unintentionally forget to mention the most relevant figure (pax capacity or cabin floor space)?
Many things are difficult, all things are possible!
 
SteelChair
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 1:25 pm

Does the 787 lend itself to structural lightening due to the composite structure?Can composite layups be done with fewer layers if the high MTOW is not needed for a short or mid range version? If one could then also lower the weight of the pylons and gear you might be able to obtain significant OEW savings.
 
RJMAZ
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 1:38 pm

rheinwaldner wrote:
Did you on purpose or unintentionally forget to mention the most relevant figure (pax capacity or cabin floor space)?

787-8
Cabin length 42.28m width 5.49m area 232m2
Max seating 381

A333-800
Cabin length 45m width 5.28m area 233m2
Max seating 406

As you can see the 787 is smaller and lighter in every possible measurement even cabin floor space and pax capacity.

So in terms of the poster who said the 787-8 is larger A330 they are flat out wrong.

The 787-8 is closest to the 767 replacement. If it went on a diet and sacrificed a bit of range it would be a perfect 767 replacement.
 
WIederling
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 1:53 pm

SteelChair wrote:
Does the 787 lend itself to structural lightening due to the composite structure?Can composite layups be done with fewer layers if the high MTOW is not needed for a short or mid range version? If one could then also lower the weight of the pylons and gear you might be able to obtain significant OEW savings.


Boeing already shaved ~~8t out of the carcass :-)
Murphy is an optimist
 
jmt18325
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 1:55 pm

LAX772LR wrote:
rnav2dlrey wrote:
UA will never buy the A330.

While I'm aware of what you're trying to say... technically, that's false:
UA is currently the owner of several A330s in fact.

AC however, is the operator.


Air Canada in their latest results said they now own all of their A330s.
 
mjoelnir
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 2:05 pm

rheinwaldner wrote:
RJMAZ wrote:
The 787-8 is actually the smallest and lightest widebody even when compared to the A330-800.
The 787-8 is lower in ever metric:
Length: 56.7m vs 58.8m
Wing span: 60.1m vs 64m
Wing area: 377m2 vs 380m2
Empty weight: 119T vs 124T
Max takeoff weight: 227T vs 242T
Fuel capacity: 126,000L vs 139,000L
Range: 7355nm vs 7500nm

The 787-8 is closer to the 767-300ER than the A330-800.

Did you on purpose or unintentionally forget to mention the most relevant figure (pax capacity or cabin floor space)?


The A330-800 is slightly larger than the 787-8 also in pax capacity and cabin floor space.
 
SteelChair
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 2:43 pm

In some metrics, the 332 is larger than the 788. The 332 is 6-7 feet longer than the 787, yet the 332ceo OEW is comparable or slightly less. The 332ceo wing area is smaller and the fuselage is 4 inches narrower than the 788. Imho, The 788 is analogous to the A318....fuselage is too short for the wing. 788 has basically the same cabin as 764 yet has shorter and wider fuselage. 788 is more optimized for long haul, which the airlines aren't looking for in MOM.

Weren't composites supposed to give us lighter airplanes, or perhaps the 788 is just too optimized for long haul? If 788 was a candidate for MOM it would have been obvious by now. Even Boeing knows that 788 is not a MOM competitor.

Perhaps the 330ceo would be the best option for UAL?
 
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flyingclrs727
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 8:14 pm

WIederling wrote:
SteelChair wrote:
Downsized airplanes usually don't work out...the 747SP, L1011-500, A310, and A318 come to mind.


Little nit: the A310 is not really a shrink of the A300 even if it is the same fuselage and cross section only shorter.

The A310 was exactly the kind of MoM step that is asked for, though in a different direction.
The A310 got a brand new fully supercritical from scratch wing.
I don' think that even the center wing box is the same.


Wasn't the A300-600 really just a stretched A310 made to the same length and capacity as the original A300?
 
RJMAZ
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Re: United eyes A330-800 for fleet replacement

Sun Mar 04, 2018 9:41 pm

SteelChair wrote:
Does the 787 lend itself to structural lightening due to the composite structure?Can composite layups be done with fewer layers if the high MTOW is not needed for a short or mid range version? If one could then also lower the weight of the pylons and gear you might be able to obtain significant OEW savings.

Yes most definitely.

If the maximum takeoff weight was reduced to say 180T Boeing would be able to remove 10% off the empty weight easily if they fully optimised it. It would no longer be able to carry high payload and fuel loads at the same time so the max payload and max fuel loads could be reduced. This reduces the max loads reached which are used to determine the strength and weight of the structural parts.

Wing bending moment is the main load determining wingbox and wing weight. The more weight in the fuselage itself the higher the wing bending moment loads so aircraft always burn the centre fuel tanks first. So all you have to do is remove weight from the fuselage. The 787-8 has a max payload of nearly 50T that's 500 passengers. So it could be lowered to 40T which reduces the max landing weight too. Reduce the max fuel capacity from 126,000L to 96,000L by eliminating the fuel tank located in the fuselage centre section. This is 35T of weight removed from the fuselage centre section which would reduce wing bending moment by a huge percentage

Just doing the above would allow for a 10% reduction in empty weight once it is optimised.

You can then look at fitting new engines. The A340's Trent 500 and A330's trent 700 has the same diameter fan but the 500 has a smaller core and higher bypass ratio. As a result the Trent 500 has a lower thrust rating but also a lower weight by more than 1000kg. A new engine for the lightweight 787-8 using the same fan could also have it's bypass ratio increased from 10:1 to 12:1. The thrust being reduced is fine as the aircraft is now lighter. Less engine weight means another 1-2% off the empty weight.

Now that the weight is right down a shorter wing will no longer compromise the aircraft. So you could get it down to code D gates this could save another 1-2% in empty weight. Let's call this the 787-4

So even though the 787-4 carries 75% less fuel it is 12-14% lighter and it's engines would have 5% better SFC being half a generation newer. So it's range wouldn't be as low as you think.

Compared to the 767-300ER it would weigh slightly more empty but with such a lower fuel burn it's takeoff weight would be lower with the same payload and fly it further.

If the maximum takeoff weight is kept the same and the wing is the same area then I doubt Boeing could remove more than 1-2% from the 787-8.

However as the 787-8 needs a full redesign to bring it up to the new production standards it can easily be optimised for a lighter weight without much additional cost.
 
RJMAZ
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 12:34 am

SteelChair wrote:
An aggressively re-worked and lightened 783 might be an option...but is probably not likely imho. Downsized airplanes usually don't work out...the 747SP, L1011-500, A310, and A318 come to mind. Early generation variants normally get marginalized fairly quickly, think 727-100, 737-100, A319, B767-200. So its hard to imagine a 783 being competitive just as the 788 gets squeezed out by its bigger brothers.

None of the examples apply as they are mostly shrinks.

They retain all of the heavy parts of the longer models but reduce the length and capacity of the cabin. They might weigh 95% of the empty weight of the larger version but can carry only 80% of the passengers. So every example you listed the empty weight per passenger is getting worse.

A lightweight 787 would not be shortening the fuselage or reducing passenger capacity. Only weight would be taken out meaning the empty weight per passenger would only be getting better. There has not be an example of this done in the past. Previous "regional" versions have simply had a reduced maximum takeoff weight on paper to reduce airport fees.

The 787-3 would have been the closest example. It was originally planned to be optimised and weigh at least 10% less than the 788-8. Budget and time constraints caused the 787-3 to turn into a simple 787-8 with its wing tips made shorter. The 787-3 was now going to be less than 5% lighter than a normal 787-8. The shorter clipped wing of the 787-3 was now carrying too much structural weight so it's short haul efficiency advantage disappeared. This caused it to be canceled. You either do it right or don't do it at all.

If Boeing wants to revise the manufacturing techniques of the 787-8 and bring it up to standard it would be the perfect opportunity to make the 787-8 lighter. They could optimise it further than the original 787-3 as it could be made to share very little structural parts with the larger 787-9 and 10. Boeing could sit it anywhere between the 787-3 weight and the current 787-8 weight.

For example some very conservative numbers.
115t empty 220t Max TO - 7000nm paper range
110t empty 200t Max TO - 6000nm paper range
105t empty 180T Max TO - 5000nm paper range
100t empty 160T Max TO - 4000nm paper range

Obviously the lighter you go the more fuel efficient the aircraft becomes. The only downside is the maximum range reduces.

SteelChair wrote:
The 788 is analogous to the A318....fuselage is too short for the wing. 788 has basically the same cabin as 764 yet has shorter and wider fuselage. 788 is more optimized for long haul, which the airlines aren't looking for in MOM.

Long wings actually improve fuel efficiency and lift to drag. It's more the large fuel and payload require the wings to be strong and heavy.

With reduced fuel and payload weight in the fuselage and a resulting lower maximum takeoff weight the wings can be made thinner and lighter while still being safe.

The 788 isn't as short and stubby as a A318 or A310. Its fineness ratio is fine and actually similar to the A320, A300, 767-200 and A380.
 
rheinwaldner
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 5:19 am

RJMAZ wrote:
rheinwaldner wrote:
Did you on purpose or unintentionally forget to mention the most relevant figure (pax capacity or cabin floor space)?

787-8
Cabin length 42.28m width 5.49m area 232m2
Max seating 381

A333-800
Cabin length 45m width 5.28m area 233m2
Max seating 406

You should know, that max seating is misleading. Having 9 abreast vs. 8 abreast the 788 on average can have more seats....
Many things are difficult, all things are possible!
 
RJMAZ
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 5:43 am

rheinwaldner wrote:
You should know, that max seating is misleading. Go through seatguru and find out the average seating for both, then you find that you are flat out wrong...

So I looked and found multiple A330-200's with over 350 seats yet i could not find a single 787's nearing 350 seats. There are more A330's with high density cabins doing short routes than there are 787's. So if you are talking average seating the A330 has far more seats on average.

Are you trying to say the 787-8 is bigger and heavier than the A330-800neo?

I posted every dimension including cabin area and the 787-8 is lower on every count. Soon you'll be saying the 787 has a taller tail and larger diameter tyres as proof it is bigger.
 
LDRA
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 6:33 am

A330-800 OEW is ~124ton, MTOW is 242ton
787-8 OEW is ~120ton, MTOW is 227ton

Given they are almost identical in cabin area, OEW delta seems to be very small, especially considering the large MTOW difference and amount of carbon composite 787 uses
 
dampfnudel
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 6:37 am

columba wrote:
A330Neo could be a stop gap solution until the NMA is ready


I have a feeling that’s what Delta is doing until their optimal 767 replacements arrive (the sooner the better).
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zeke
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 7:12 am

RJMAZ wrote:

If the maximum takeoff weight was reduced to say 180T Boeing would be able to remove 10% off the empty weight easily if they fully optimised it. It would no longer be able to carry high payload and fuel loads at the same time so the max payload and max fuel loads could be reduced. This reduces the max loads reached which are used to determine the strength and weight of the structural parts.


Sorry that is just hogwash, there would be nothing “easy” about removing 10-20 tonnes (your 10%) out of the 787.

It is not just a matter of fewer layers of composite, everything still needs to be joined, still need lightning protection, still need to carry and support the various systems within the structure.

The amount of work involved may as design a new aircraft.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
RJMAZ
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 11:09 am

LDRA wrote:
A330-800 OEW is ~124ton, MTOW is 242ton
787-8 OEW is ~120ton, MTOW is 227ton

Given they are almost identical in cabin area, OEW delta seems to be very small, especially considering the large MTOW difference and amount of carbon composite 787 uses

The 787-8 is quite heavy considering its lower max takeoff weight. This is why I think there is some fat to trim. If the max takeoff weight dropped below 200T even more weight could be removed.

zeke wrote:
Sorry that is just hogwash, there would be nothing “easy” about removing 10-20 tonnes (your 10%) out of the 787.

It is not just a matter of fewer layers of composite, everything still needs to be joined, still need lightning protection, still need to carry and support the various systems within the structure.

The amount of work involved may as design a new aircraft.

The A300 Vs A330 shows how much weight can be removed from a similar sized fuselage. That is a 25% reduction in empty weight with the fuselage length shortened by only 7%. That empty weight reduction was possible because the max takeoff weight was reduced by 30%.

The same would apply to the 787-8. If you reduced the maximum takeoff weight by 20% then a 10% reduction in empty weight is conservative compared to the A300, A330 example.

Boeing has to spend big money on the 787-8 to get its production costs down. Lots of parts of the 787-8 will still remain unique to the 787-8 due to it being smaller and slightly lighter. So it would be no extra cost for these parts to be optimised for lower loads and be made lighter still.

And yes removing layers of carbon fibre and machining parts thinner is exactly how this would be done.

Fully optimising a 787-3 would cost a fraction of the cost of a clean sheet widebody. Of course it would never be as good or as cheap to produce as a clean sheet design. If Boeing can get 50% of the orders while spending only 20% the amount by developing a 787-3 then it would get the green light.

This lightweight structure and new smaller but higher bypass ratio engine developed for a new 787-3 could also be used on a shorter fuselage 787-2.

787-10 - 68m long 242T MTO 6430nm range
787-9 - 62m long 242T MTO 7635nm range

787-3 - 56M long 180T MTO ~5000nm range
787-2 - 50m long 180T MTO ~6000nm range

I don't see how this couldn't completely satisfy the MOM requirement for a fraction of the cost of a clean sheet.
 
StTim
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 11:29 am

Taking weight out of an airframe is an constant and ongoing process. The low hanging fruit - to use that awful management speak - are what happens first. The other thing is that weight has to be taken out in the right places - or you end up carrying ballast - to allow the CoG to remain in the right area. I believe the 747 used to have a lump (ok an engineered lump) of depleted Uranium in the tail to give the correct balance. So it was no use taking more weight out of the aft section as that would just have required a bugger lump!
 
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seahawk
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 11:43 am

RJMAZ wrote:
LDRA wrote:
A330-800 OEW is ~124ton, MTOW is 242ton
787-8 OEW is ~120ton, MTOW is 227ton

Given they are almost identical in cabin area, OEW delta seems to be very small, especially considering the large MTOW difference and amount of carbon composite 787 uses

The 787-8 is quite heavy considering its lower max takeoff weight. This is why I think there is some fat to trim. If the max takeoff weight dropped below 200T even more weight could be removed.

zeke wrote:
Sorry that is just hogwash, there would be nothing “easy” about removing 10-20 tonnes (your 10%) out of the 787.

It is not just a matter of fewer layers of composite, everything still needs to be joined, still need lightning protection, still need to carry and support the various systems within the structure.

The amount of work involved may as design a new aircraft.

The A300 Vs A330 shows how much weight can be removed from a similar sized fuselage. That is a 25% reduction in empty weight with the fuselage length shortened by only 7%. That empty weight reduction was possible because the max takeoff weight was reduced by 30%.

The same would apply to the 787-8. If you reduced the maximum takeoff weight by 20% then a 10% reduction in empty weight is conservative compared to the A300, A330 example.

Boeing has to spend big money on the 787-8 to get its production costs down. Lots of parts of the 787-8 will still remain unique to the 787-8 due to it being smaller and slightly lighter. So it would be no extra cost for these parts to be optimised for lower loads and be made lighter still.

And yes removing layers of carbon fibre and machining parts thinner is exactly how this would be done.

Fully optimising a 787-3 would cost a fraction of the cost of a clean sheet widebody. Of course it would never be as good or as cheap to produce as a clean sheet design. If Boeing can get 50% of the orders while spending only 20% the amount by developing a 787-3 then it would get the green light.

This lightweight structure and new smaller but higher bypass ratio engine developed for a new 787-3 could also be used on a shorter fuselage 787-2.

787-10 - 68m long 242T MTO 6430nm range
787-9 - 62m long 242T MTO 7635nm range

787-3 - 56M long 180T MTO ~5000nm range
787-2 - 50m long 180T MTO ~6000nm range

I don't see how this couldn't completely satisfy the MOM requirement for a fraction of the cost of a clean sheet.


Because with a CFRP barrel, a lighter design is by all means a new design. The laying of the CFRP and the thickness of the CFRP barrel needs to be changed, which means you redo the whole CFRP design.
 
RJMAZ
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 11:58 am

seahawk wrote:
Because with a CFRP barrel, a lighter design is by all means a new design. The laying of the CFRP and the thickness of the CFRP barrel needs to be changed, which means you redo the whole CFRP design.

That is what Boeing planned to do with the original 787-3.

That is what Boeing will have to do even if it wants to bring the 787-8 up to 787-9 standard. I highly doubt Boeing would want to make the 787-8 a simple shrink of the 787-9. This would make it heavier and turn it into a niche 9000nm aircraft. This is why going lighter makes sense.

The lighter optimization will cost nothing on some parts as the same optimization process would have been done anyway just at a higher weight/ load level.

The big bonus is Boeing now has in service experience so it knows where they can make it thinner to save weight. So there goes another 1% of empty weight.
 
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zeke
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 12:12 pm

RJMAZ wrote:
The A300 Vs A330 shows how much weight can be removed from a similar sized fuselage. That is a 25% reduction in empty weight with the fuselage length shortened by only 7%. That empty weight reduction was possible because the max takeoff weight was reduced by 30%.

The same would apply to the 787-8. If you reduced the maximum takeoff weight by 20% then a 10% reduction in empty weight is conservative compared to the A300, A330 example.


The large difference between the A330 and A300 is not 4 meters in fuselage, it is the 20 meters of of wingspan, it is having double the fuel capacity, it is having 50% more thrust each side, it is having landing gear that can withstand an additional 50 tonnes.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
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seahawk
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 12:30 pm

RJMAZ wrote:
seahawk wrote:
Because with a CFRP barrel, a lighter design is by all means a new design. The laying of the CFRP and the thickness of the CFRP barrel needs to be changed, which means you redo the whole CFRP design.

That is what Boeing planned to do with the original 787-3.

That is what Boeing will have to do even if it wants to bring the 787-8 up to 787-9 standard. I highly doubt Boeing would want to make the 787-8 a simple shrink of the 787-9. This would make it heavier and turn it into a niche 9000nm aircraft. This is why going lighter makes sense.

The lighter optimization will cost nothing on some parts as the same optimization process would have been done anyway just at a higher weight/ load level.

The big bonus is Boeing now has in service experience so it knows where they can make it thinner to save weight. So there goes another 1% of empty weight.


Which leaves you with a wing optimized for too much fuel capacity, engines with too much thrust and a MLG designed for too much MTOW and MLW.
 
mjoelnir
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 12:52 pm

If Airbus would want to do a smaller wide body than the A330, they could go back to the A300 fuselage and do a new wing, using the new wing box developed. It is the nearly ideal fuselage profile, combining good passenger volume with good freight capabilities. I do not think that on short to medium haul drag would be the overriding consideration, but OEW would be. Reducing fuel burn by reducing weight would be the main consideration, producing it for a low price the second on. Short time to market the third one.
A right sized engine could be the GEnx-2b. It is the current state of the art.

Together with a super A321 it would squeeze a possible Boeing NMA from above and below.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:01 pm

mjoelnir wrote:
If Airbus would want to do a smaller wide body than the A330, they could go back to the A300 fuselage and do a new wing, using the new wing box developed. It is the nearly ideal fuselage profile, combining good passenger volume with good freight capabilities. I do not think that on short to medium haul drag would be the overriding consideration, but OEW would be. Reducing fuel burn by reducing weight would be the main consideration, producing it for a low price the second on. Short time to market the third one.
A right sized engine could be the GEnx-2b. It is the current state of the art.

Together with a super A321 it would squeeze a possible Boeing NMA from above and below.

I love how all these threads wrap around to "put new engine on old airframe no longer in production".
I don't think we're going to see Airbus follow up A330neo with A300neo.
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:04 pm

Why should you go back to a 1960ies fuselage, when you are doing a new plane. You can probably design a new fuselage faster than it would take to import the old data into CATIA, then find those parts that are no longer certifiable or can no longer be produced due to materials no longer being up to standard.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:12 pm

zeke wrote:
The large difference between the A330 and A300 is not 4 meters in fuselage, it is the 20 meters of of wingspan, it is having double the fuel capacity, it is having 50% more thrust each side, it is having landing gear that can withstand an additional 50 tonnes.

You've just explained why the 787-3 will be lighter.

The same all applies to an optimized 787-3. It will have 10m less wingspan 75% the fuel capacity, 20% less thrust each side and lighter landing gear due to weights 40-50T lower.

seahawk wrote:
Which leaves you with a wing optimized for too much fuel capacity, engines with too much thrust and a MLG designed for too much MTOW and MLW.

Too much fuel in the wings?

The 787 carries a huge percentage of it's fuel in the actual fuselage centre tank. Deleting this centre tank saves weight and provides a greater reduction in wing root bending moment than if the same fuel was removed from the wings. The remaining fuel in the wings is actually the perfect amount to perform 767-300ER missions.

Engines with too much thrust?
New engines fix this. Smaller core, higher bypass ratio, same fan diameter means less thrust and less weight. Whatever engine is in the works to replace the 787's engines in 10-15 years derate them to make the new tech durable and produce that. The Rolls-Royce advance prototype engine already in testing is half a generation ahead of the 787's Trent 1000's. With a new smaller hotter core driving the A350 fan. Put a 787 fan on front and you've instantly for something with higher bypass and more fuel efficient than what is on the 787. GE probably have something in the works to improve on the genX.

MLG designed for extra weight?
Open up strut leg in cad design software. Reduce thickness by 10%. Starting machining. Simple. All the attachment points would be the same it would just be machined lighter with a finite element loading optimisation done of course. Same deal with most of the structural parts.

Boeing beefed up a lot of parts for the 787-10 so it knows where parts could be lightened.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:16 pm

mjoelnir wrote:
If Airbus would want to do a smaller wide body than the A330, they could go back to the A300 fuselage and do a new wing, using the new wing box developed. It is the nearly ideal fuselage profile, combining good passenger volume with good freight capabilities. I do not think that on short to medium haul drag would be the overriding consideration, but OEW would be. Reducing fuel burn by reducing weight would be the main consideration, producing it for a low price the second on. Short time to market the third one.
A right sized engine could be the GEnx-2b. It is the current state of the art.

Together with a super A321 it would squeeze a possible Boeing NMA from above and below.

Why do you think the fuselage is the most expensive part of the aircraft, and the part that takes most of the development time? Your A300neo will need a new wing, new engines, likely new materials, and new systems (or is Airbus going to continue using 70s era systems that have little in common with the rest of their aircraft?). That is not a low cost/quick development airplane. That is essentially a brand new aircraft that just happens to use the same fuselage (like the A340/A330 vs A300, or 727/737/757 vs 707).

Rewinging aircraft is not cheap. It is cheaper than an all new aircraft, but the super A321 as you call it will still be a several billion dollars program. Your A300neo idea will be even more expensice than that, as the A300 needs a lot more work to make competive in the modern environment. In the end your super A321 + A300neo would probably cost Airbus a similar amount of money as the 797 would Boeing. If you are spending that amount of coin it starts to beg the question on why you don’t just make your own clean sheet.
Last edited by Polot on Mon Mar 05, 2018 1:45 pm, edited 1 time in total.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:28 pm

Isn't A300 and A330 fuselage width almost similar? It would make more sense to have let's say, a A330-100 than resurrecting A300, with corresponding reduction in other areas like wingspan, center wingbox, landing gear etc.
 
Geoff1947
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:35 pm

ro1960 wrote:
trex8 wrote:
Polot wrote:
Its mentioned here because UA mentions it, even if you want to pretend that they don't/are not actually considering it. You realize that UA may decide to just work with what they have, maybe pick up a few more used 767s, and wait right? It is not like UA could get the A338 before ~2020 anyways.

A338 is supposed to EIS 2019, originally they said a year after A339 which I think they are still hoping is still first half 2018 or at least Q3 per TAP, no idea how many A330ceo/neo slots are free for 2019.
But then there may be 6 slots free soon if certain rumors are true!


The first two A330neo for TP just rolled out of the paint shop. Any idea about the EIS?

https://worldairlinenews.com/2018/03/03/a-double-roll-out-for-the-first-airbus-a330neo-operator-tap-air-portugal/


Last report was July 2018.

Geoff
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:43 pm

RJMAZ wrote:
Deleting this centre tank saves weight and provides a greater reduction in wing root bending moment than if the same fuel was removed from the wings.


There really is nothing to delete. you could save a bit on piping and sealant probably.
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:45 pm

B777LRF wrote:
It might not be an optimised solution, but QR are running a large fleet of 787-8s on DOH-Europe services.


This is the one that interests me and seems to be rarely discussed. QR essentially use their large fleet of 788s as their MOM aircraft and yet appear to me to be the only airline taking that approach. So either QR are smarter and more visionary than all other airlines or are being stupid.
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 1:46 pm

mjoelnir wrote:
A right sized engine could be the GEnx-2b. It is the current state of the art.


Quickly looking at the characteristics of each engine (thrust in particular, but also weight), the GEnx-2b seems much closer to the CF-6 found on the A330 than to the engines that used to be mounted on the A300/A310. In fact, I fear the issue would be to find a right sized engine for such a plane, ideally in the 55klbs thrust range...
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 2:01 pm

Polot wrote:
mjoelnir wrote:
If Airbus would want to do a smaller wide body than the A330, they could go back to the A300 fuselage and do a new wing, using the new wing box developed. It is the nearly ideal fuselage profile, combining good passenger volume with good freight capabilities. I do not think that on short to medium haul drag would be the overriding consideration, but OEW would be. Reducing fuel burn by reducing weight would be the main consideration, producing it for a low price the second on. Short time to market the third one.
A right sized engine could be the GEnx-2b. It is the current state of the art.

Together with a super A321 it would squeeze a possible Boeing NMA from above and below.

Why do you think the fuselage is the most expensive part of the aircraft, and the part that takes most of the development time? Your A300neo will need a new wing, new engines, likely new materials, and new systems (or is Airbus going to continue using 70s era systems that have little in common with the rest of their aircraft?). That is not a low cost/quick development airplane. That is essentially a brand new aircraft that just happens to use the same fuselage (like the A340/A330 vs A300, or 727/737/757 vs 707).

Rewinging aircraft is not cheap. It is cheaper than an all new aircraft, but the super A321 as you call it will still be a several billion dollars program. Your A300neo idea will be even more expensice than that, as the A300 needs a lot more work to make competive in the modern environment. In the end your super A321 + A300neo would probably cost Airbus a similar amount of money as the 797 would Boeing. If you are spending that amount of coin it starts to beg the question on why you don’t just make your own clean sheet.



Why do people have to put words into somebodies writing that are not there? Where did I say that the development would be cheap? The point to be competitive is a new wing. The fuselage is the least bother if you want to be competitive, but it would still help to have a starting point for development. Anything Airbus would do to counter a MOM, NMA or 797 includes a new wing. Regarding the wing design, Airbus could do a combined wing development, larger for the A300 fuselage (not a A300neo) and smaller for the super A321, connected to a wing box of two sizes, but of similar design. The A300 fuselage is there, a new wing box design is waiting for a use, and why the hell should it be possible to make a 777-X competitive with a new wing and utterly impossible for Airbus to do something similar.
But the main point would be, that a suitable engine would be available today, not ten years in the future.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 2:17 pm

mjoelnir wrote:
Polot wrote:
mjoelnir wrote:
If Airbus would want to do a smaller wide body than the A330, they could go back to the A300 fuselage and do a new wing, using the new wing box developed. It is the nearly ideal fuselage profile, combining good passenger volume with good freight capabilities. I do not think that on short to medium haul drag would be the overriding consideration, but OEW would be. Reducing fuel burn by reducing weight would be the main consideration, producing it for a low price the second on. Short time to market the third one.
A right sized engine could be the GEnx-2b. It is the current state of the art.

Together with a super A321 it would squeeze a possible Boeing NMA from above and below.

Why do you think the fuselage is the most expensive part of the aircraft, and the part that takes most of the development time? Your A300neo will need a new wing, new engines, likely new materials, and new systems (or is Airbus going to continue using 70s era systems that have little in common with the rest of their aircraft?). That is not a low cost/quick development airplane. That is essentially a brand new aircraft that just happens to use the same fuselage (like the A340/A330 vs A300, or 727/737/757 vs 707).

Rewinging aircraft is not cheap. It is cheaper than an all new aircraft, but the super A321 as you call it will still be a several billion dollars program. Your A300neo idea will be even more expensice than that, as the A300 needs a lot more work to make competive in the modern environment. In the end your super A321 + A300neo would probably cost Airbus a similar amount of money as the 797 would Boeing. If you are spending that amount of coin it starts to beg the question on why you don’t just make your own clean sheet.



Why do people have to put words into somebodies writing that are not there? Where did I say that the development would be cheap? The point to be competitive is a new wing. The fuselage is the least bother if you want to be competitive, but it would still help to have a starting point for development. Anything Airbus would do to counter a MOM, NMA or 797 includes a new wing. Regarding the wing design, Airbus could do a combined wing development, larger for the A300 fuselage (not a A300neo) and smaller for the super A321, connected to a wing box of two sizes, but of similar design. The A300 fuselage is there, a new wing box design is waiting for a use, and why the hell should it be possible to make a 777-X competitive with a new wing and utterly impossible for Airbus to do something similar.
But the main point would be, that a suitable engine would be available today, not ten years in the future.

No one said it couldn’t be competitive. You are the one talking about low cost short time on the market solution. Your A300neo would not be a low cost short time on the market solution, just like the 777X is not a low cost short time on the market solution. There is no wing box design for the A300 just sitting on Airbus’s computer waiting for use, and the wing is just one of many changes Airbus would have to make to the A300. By the time the A300neo is ready the GEnx’s will be 10+ years old with more efficient options for new planes on the horizon.

Airbus only wants to do a A320++ at most (ideally they want the current situation and to do nothing else at all but enjoy A321LR sales). They don’t want to do a small wodebody in addition because that costs money Airbus does not want to spend for a questionable market (especially questionable for two expensive entrants). That is why Airbus is constantly saying the A338 is a MOM and why Boeing is allegedly trying to kill any sales for the plane.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 2:23 pm

WIederling wrote:
SQ789 wrote:
Wow interesting, I bet these will result the A350 order cancellation?


reflexive some?

A330 or MoM would be a different size slot than "A359" wouldn't it?

Image
src: https://pbs.twimg.com/media/DXJfUmnW4AAra_y.jpg
OT from the A350 production thread.


Hahahaha, that chart has me laughing. It is obviously pitching A350s to replace 777-200ERs. There are exaggerations all over the place. They used United logos, but no one bothered to check that United has 252 seats on the 789 and 267 on the 772. They show a 40 seat gap so that the 787 looks too small. And how doesn’t the 18 foot stretch on the 787-10 result in a 70 seat difference? Boeing says the difference is 40seats. I am also surprised the 789 has much more range than the A350. Airbus marketing is amazing at defying reality :)

Such a chart for the 767 would have the A330-800clearly in the too much range column.
Last edited by Newbiepilot on Mon Mar 05, 2018 2:33 pm, edited 3 times in total.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 2:25 pm

I also smile at the idea that all that is necessary to reduce weight in a CFRP structure is to remove a few layers. It is nothing like that. CFRP is not like a metal alloy where strength is pretty much unidirectional. Remove some thickness and the strength in all directions is affected. In CFRP the strength is related to the directions of the fibres. This has good and bad results. The good is you can accurately design the part for the stresses and stress directions it will have. Remove a layer and that strength distribution will change and is now probably sub-optimal. So do you redesign the complete layering up process?

Having seen how F1 parts were made with Carbon Fibre 20 years ago I know directionality was vitally important back then.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 2:27 pm

Revelation wrote:
mjoelnir wrote:
If Airbus would want to do a smaller wide body than the A330, they could go back to the A300 fuselage and do a new wing, using the new wing box developed. It is the nearly ideal fuselage profile, combining good passenger volume with good freight capabilities. I do not think that on short to medium haul drag would be the overriding consideration, but OEW would be. Reducing fuel burn by reducing weight would be the main consideration, producing it for a low price the second on. Short time to market the third one.
A right sized engine could be the GEnx-2b. It is the current state of the art.

Together with a super A321 it would squeeze a possible Boeing NMA from above and below.

I love how all these threads wrap around to "put new engine on old airframe no longer in production".
I don't think we're going to see Airbus follow up A330neo with A300neo.


A resigned A300 is about one of the worst ideas I have read in a while. The systems architecture including the flight deck on that plane is almost entirely obsolete.
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 3:04 pm

Newbiepilot wrote:
Hahahaha, that chart has me laughing. .


you can continue breathing now.
( There has been enough discussion in that other thread already.)

Posting this was tangent the "different basket" thing of deciding on A350 ( as shown in the graphic )
and deciding on A330 and/or MoM type frame for a different fleet decission.

Actually even wider scoped than talked about, see the original article on FG:
https://www.flightglobal.com/news/artic ... nt-446322/


apropos, take the attribution as what you want to see in it:
https://twitter.com/e_russell/status/968941766782144515
Last edited by WIederling on Mon Mar 05, 2018 3:13 pm, edited 1 time in total.
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 3:07 pm

Newbiepilot wrote:
A resigned A300 is about one of the worst ideas I have read in a while.


The A300 has long been "resigned". Do you want to open a tin like for the 757 " A shouldn't have closed the ... ". :-?
Murphy is an optimist
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 3:12 pm

Newbiepilot wrote:
A resigned A300 is about one of the worst ideas I have read in a while.

Isn't that part of the reason why it would be re-designed?
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 3:20 pm

DartHerald wrote:
Newbiepilot wrote:
A resigned A300 is about one of the worst ideas I have read in a while.

Isn't that part of the reason why it would be re-designed?

Yes but with such an extensive redesign it starts to become questionable if you are even making a “A300neo” anymore. Airbus is not trying to outright destroy Boeing in the market, they want a return on their investment. They are going to avoid a scorch Earth approach where they are rewinging and stretching A320s while also creating a new “A300neo” that hopefully won’t cause problems with the A330neo program. That is an Airbus fanboy fantasy, not a realistic proposition. Only way both planes happen is if the 797 really takes off and the stretched rewing A321 just doesn’t cut it with the airlines (at which point Airbus will now be coming from behind in the market)
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 4:02 pm

RJMAZ wrote:
The same all applies to an optimized 787-3. It will have 10m less wingspan 75% the fuel capacity, 20% less thrust each side and lighter landing gear due to weights 40-50T lower.


The 783 is a 788 with wingtips that have been cutoff and the same 788 engines that have been derated, it is 8% lighter than a 788. It is nothing like the A300 compared to the A330 difference, the A300 is 28% lighter.
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 4:17 pm

B777LRF wrote:
The 787 is proving to be a money maker, 'even' in -8 disguise


Selling planes and making money with them are 2 very different things...
 
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Re: United eyes A330-800 for fleet replacement

Mon Mar 05, 2018 4:29 pm

WIederling wrote:
Newbiepilot wrote:
A resigned A300 is about one of the worst ideas I have read in a while.


The A300 has long been "resigned". Do you want to open a tin like for the 757 " A shouldn't have closed the ... ". :-?


Darn autocorrect. Rewinged

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