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Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 3:00 pm
by keesje
Will Airbus ever launch a dedicated replacement to fill their A320 series - A330 series gap ?

A300 and A310 production was ended long ago. An A321LR will do TATL. But with 170-180 passengers only and Western Europe- US North East at max. range, just like the 757.

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Airbus is not famous for wait and see / react / copy (A300 big twin, A320FBW, A320NEO, A330/340 combi, A350, A380, A400M). They seem neither understaffed, under financed or shy.

The A330 won't fly forever. I can imagine they feel it must be prevented airlines order a Boeing MoM because of no alternative. Customers rule, competition helps innovation, cleaner skies are required & European / French jobs must be secured :wink2: :wink2:

What if a 2500 a/c market is there? Maybe something a little lighter, leaner and smaller than a 2-3-2 abreast Boeing MoM?

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Airbus A370-800 60t Medium Concept

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 3:23 pm
by ACCS300
Would love a widebody MOM airliner like the A310 or 767 rather than a juiced-up narrow body like the A321neoLR. Nothing more pleasurable than a long-haul trip on a mini-jumbo like the 767.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 3:42 pm
by Newbiepilot
I think it depends on the A330neo. The A338 only has 6 orders and some consider it overbuilt and heavy for shorter flights. If the A338 dies, the Airbus gap between the A321 and A339 is quite big.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 3:49 pm
by B777LRF
The thing is, if Airbus were to make a Regional version of the A338 (plug the centre-tank, fit lighter gear, reduce MTOW), they'd have a pretty persuasive product at next-to-nothing in R&D costs.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 3:59 pm
by Newbiepilot
Keesje has pitched the A330-700 before. The A330 -800 could use the diet first. Its OEW is speculated to be within 2% of the A339 since the A332 is within 2% of the A333. Back in the 1990s that shrink was a great idea since the A333 was limited by its MTOW. The MTOW of the A333 and A339 has grown to make the benefits of a smaller ultra long range A330neo slim. I think everything depends on what Airbus wants to do with the A338.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:02 pm
by Bricktop
I thought the company line parroted here was that Airbus has MOM covered with their current lineup. After JL leaves, maybe. Selfish me hopes they go with a twin aisle 2-3-2, my favorite configuration because I only do TATL overseas now.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:04 pm
by Whalejet
The concerns around the A330-800 seem eerily similar to those surrounding the 787-300. Yes, they are different ranges (one flies 13000km, the other 5000km) but it seems like more airlines are going for the A350-900. A330-700 seems like a good plane for short-intermediate routes.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:04 pm
by Bricktop
Newbiepilot wrote:
Keesje has pitched the A330-700 before. The A330 -800 could use the diet first. Its OEW is speculated to be within 2% of the A339 since the A332 is within 2% of the A333. Back in the 1990s that shrink was a great idea since the A333 was limited by its MTOW. The MTOW of the A333 and A339 has grown to make the benefits of a smaller ultra long range A330neo slim. I think everything depends on what Airbus wants to do with the A338.

Isn't it A-net doctrine that shrinks suck?

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:11 pm
by Newbiepilot
Bricktop wrote:
Newbiepilot wrote:
Keesje has pitched the A330-700 before. The A330 -800 could use the diet first. Its OEW is speculated to be within 2% of the A339 since the A332 is within 2% of the A333. Back in the 1990s that shrink was a great idea since the A333 was limited by its MTOW. The MTOW of the A333 and A339 has grown to make the benefits of a smaller ultra long range A330neo slim. I think everything depends on what Airbus wants to do with the A338.

Isn't it A-net doctrine that shrinks suck?


I'm not the biggest fan of a.net doctrine, but that is correct. The A332 was a popular shrink but probably because the A333 was underpowered with low MTOW at the time. That is no longer true, so yes I agree the simple shrink A338 likely sucks, but is Airbus willing to admit that yet? Have they even officially cancelled the A358 yet?

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:17 pm
by Bricktop
Newbiepilot wrote:
Bricktop wrote:
Newbiepilot wrote:
Keesje has pitched the A330-700 before. The A330 -800 could use the diet first. Its OEW is speculated to be within 2% of the A339 since the A332 is within 2% of the A333. Back in the 1990s that shrink was a great idea since the A333 was limited by its MTOW. The MTOW of the A333 and A339 has grown to make the benefits of a smaller ultra long range A330neo slim. I think everything depends on what Airbus wants to do with the A338.

Isn't it A-net doctrine that shrinks suck?


I'm not the biggest fan of a.net doctrine, but that is correct. The A332 was a popular shrink but probably because the A333 was underpowered with low MTOW at the time. That is no longer true, so yes I agree the simple shrink A338 likely sucks, but is Airbus willing to admit that yet? Have they even officially cancelled the A358 yet?

IIRC the A358 went away when the A330neo was announced. Airbus nudged users to the A359 except for a few who went to the A338, like HI. But that has its own sales issues right now too.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:33 pm
by william
Airbus is in the same boat as Boeing, if one is going to spend that kind of cash on a platform it better cover more than just a niche market. Like an A320 family replacement. However,A321s are selling at near sticker and why would Airbus want to mess that cash cow up? Airbus accountants and investors would have one fired and thrown out of the Toulouse.

It would have to be an A330 replacement which would provide better separation from the A350. But Airbus is not in any hurry to develop another aircraft right now, as the CEO has stated, they are enjoying the ROI profits from present products.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:38 pm
by Aptivaboy
Because Boeing is going after that slice of the market, a market that Airbus currently dominates. I'm sure that Airbus doesn't want to lose it, so a shrink would be a nice, low risk way of ensuring further orders. At some point, manufacturers have to be concerned about simply selling planes, regardless of what type. Any sale is a good sale, unless there's something very wrong with the accounting and pricing, be it an A321 or a A330 derivative. I suspect Airbus is doing some low to mid level explorations of the concept just to be certain of the economics, and as Boeing's MOM gets firmed up and the details released, they'll likely reexamine their A330 shrink plans for viability.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:39 pm
by Aptivaboy
Because Boeing is going after that slice of the market, a market that Airbus currently dominates. I'm sure that Airbus doesn't want to lose it, so a shrink would be a nice, low risk way of ensuring further orders. At some point, manufacturers have to be concerned about simply selling planes, regardless of what type. Any sale is a good sale, unless there's something very wrong with the accounting and pricing, be it an A321 or a A330 derivative. I suspect Airbus is doing some low to mid level explorations of the concept just to be certain of the economics, and as Boeing's MOM gets firmed up and the details released, they'll likely reexamine their A330 shrink plans for viability; there's nothing wrong with being careful.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:39 pm
by Newbiepilot
william wrote:
Airbus is in the same boat as Boeing, if one is going to spend that kind of cash on a platform it better cover more than just a niche market. Like an A320 family replacement. However,A321s are selling at near sticker and why would Airbus want to mess that cash cow up? Airbus accountants and investors would have one fired and thrown out of the Toulouse.

It would have to be an A330 replacement which would provide better separation from the A350. But Airbus is not in any hurry to develop another aircraft right now, as the CEO has stated, they are enjoying the ROI profits from present products.


I don't see Airbus eager to launch a whole new development project. They aren't yet enjoying the ROI from current products since the A320neo and A330neo programs are facing delays pushing out deliveries due to engine problems. Delivery delays hurt cash flow and revenue. The A350 has gone through significant supply chain problems too. The A400m is also draining money and resulting in large charges. The underlying business is healthy, but Airbus is probably more focused on executing its current programs than launching something new. Once the production problems are addressed, I think Airbus will have more interest in launching something new.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:39 pm
by raylee67
The A310 sits 220 people in standard config. Isn't that exactly how many people the A321NEO sits? I would think the A321NEO and the A321NEO-LR are technically replacing A310 already.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:42 pm
by cledaybuck
1. I see no reason for Airbus to make a move first in this market. It is a market they currently own with the A321.
2. If Airbus does eventually need to address this market, a A330 shrink will not get it done.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:46 pm
by Newbiepilot
raylee67 wrote:
The A310 sits 220 people in standard config. Isn't that exactly how many people the A321NEO sits? I would think the A321NEO and the A321NEO-LR are technically replacing A310 already.


SATA has 18J 204Y in their A310. That is about 30 more seats than an A321 would fit.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:47 pm
by JetBuddy
I think Airbus will wait and see what the Boeing MoM is shaping up to. Airbus seem to always deny any new projects until the day it's launched. That was the case with the A330neo and the A321LR. They'll continue to say the A321LR and A330neo covers the "MoM" until suddenly it doesn't. I do agree with Keesje that Airbus seem to be in better shape to take on a new project than Boeing at this time.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 4:55 pm
by seahawk
The same basic design and market problems that are faced by Boeing are also faced by Airbus.

1. 2-3-2 is very inefficient seating solution / 2-4-2 either ends up too chubby or too big
2. the market segment assigned to the MoM is anything but uniform. Reaching from less than 200 seats with 5000+nm range to more than 300 seats and less than 3000nm range.
3. the gap between current widebodies of 787 / A330 size will be reduced with the A320/737 replacement, as everybody expect the A320/737-8 size to be the smallest on offer

Airbus is in the comfortable position that they could serve the 300 seats/5000+nm range market with a lighter and MTOW reduced A330 for very little effort, they do cover the 200 seats 3500-4000nm range market at the moment and could cover the 220-240/4000nm range market with limited effort.

And as I always said. If the market is big enough to warrant a complete new design, it is surely big enough to warrant a new wing or a new MLG and some lighter structures.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:10 pm
by LPSHobby
I have a question:

if one of the planemakers, either Boeing or Airbus, launch a newly designed MoM, will the other manufacturer follow with a too newly designed too? Is there a market for a Boeing and Airbus MoMs at the same time?

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:17 pm
by LAX772LR
B777LRF wrote:
The thing is, if Airbus were to make a Regional version of the A338 (plug the centre-tank, fit lighter gear, reduce MTOW), they'd have a pretty persuasive product at next-to-nothing in R&D costs.

Persuasive to who?

Why would they make that (or why would any customer want that), when they could do the same with an A339, and have something with similar cost but more capacity? The amount of carriers flying A332s in regional service today, is minuscule compared to those flying A333s, for primarily that reason.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:19 pm
by Taxi645
william wrote:
It would have to be an A330 replacement which would provide better separation from the A350. But Airbus is not in any hurry to develop another aircraft right now, as the CEO has stated, they are enjoying the ROI profits from present products.


Indeed. By 2025 the relevant gap is between the A320 and the A350 rather than the A330. The A330 platform has already over extended it's range requirement and even more so by the time higher thrust GTF's become available. I reckon by that time it's more useful to do a complete redesign. Indeed to better separate it from the A350 and also to better suit MoM-ish missions. I could imagine a combo like below, but probably it would end in only the larger variant and misuse it for shoter range. 8-abreast 5.5m circular fuselage. Make the side walls thinner and move the floor up a few cm's compared to the A330 to keep room for the LD3, with acceptable cabin space. Share engines with A380NEO.

Short-Medium range, 175T MTOW, 51.9m wingspan, 54.000 lbf GTF
A360-500: 54m, 285 seats (2cl.), 5200nm
A360-600: 60m, 330 seats (2cl.), 4500nm

A year or two later do the A330 replacement:

Medium-long range range, 215T MTOW, 62m wingspan, 62.000 lbf GTF
A360-900: 60m, 270 seats, 7200nm
A360-1000, 67m, 310 seats, 6300nm

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:25 pm
by seahawk
One wonders how you would find a 20% reduction in OEW over the 787, while offering similar size and range...

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:34 pm
by Polot
seahawk wrote:
One wonders how you would find a 20% reduction in OEW over the 787, while offering similar size and range...

Yeah. There may be engines for that in 2025 but the advanced materials required won't be there yet.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:42 pm
by Taxi645
seahawk wrote:
One wonders how you would find a 20% reduction in OEW over the 787, while offering similar size and range...


Why would it have similar size and range? That's more the A350 role. If you're aiming for more differentiation to the A350 is doesn't make sense basing it on the capabilities of an even more capable plane than the A330, the 787. The A330 replacement doesn't need the size nor range of the 787 and, as Polot say's, can make use of GTF and other SFC improvements. I think the smallest possible diameter 8-abreast that still accepts LD3's would make sense.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 5:51 pm
by Polot
Taxi645 wrote:
seahawk wrote:
One wonders how you would find a 20% reduction in OEW over the 787, while offering similar size and range...


Why would it have similar size and range? That's more the A350 role. The A330 replacement doesn't need the size nor range of the 787 and, as Polot say's, can make use of GTF and other SFC improvements. I think the smallest possible 8-abreast that still accepts LD3's would make sense.

Your proposed A360-500/600/900/1000 are very similar in size to the 788/789/789/78X respectively. You basically just subtracted 2m from the length, while also (for the 900/1000) added 2m to the wing. The A350-900/1000 ranges are very similar to the 787-9/10 ranges (off by ~200 nm).

Your proposed weights for the variants (175/215T) is probably a tad optimistic.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 6:11 pm
by william
seahawk wrote:
The same basic design and market problems that are faced by Boeing are also faced by Airbus.

1. 2-3-2 is very inefficient seating solution / 2-4-2 either ends up too chubby or too big
2. the market segment assigned to the MoM is anything but uniform. Reaching from less than 200 seats with 5000+nm range to more than 300 seats and less than 3000nm range.
3. the gap between current widebodies of 787 / A330 size will be reduced with the A320/737 replacement, as everybody expect the A320/737-8 size to be the smallest on offer

Airbus is in the comfortable position that they could serve the 300 seats/5000+nm range market with a lighter and MTOW reduced A330 for very little effort, they do cover the 200 seats 3500-4000nm range market at the moment and could cover the 220-240/4000nm range market with limited effort.

And as I always said. If the market is big enough to warrant a complete new design, it is surely big enough to warrant a new wing or a new MLG and some lighter structures.


A shrink has never been a marketing success in the past, and all of a sudden it will now? Especially against a new platform? And depending on what Boeing comes up with, this shrink may not be "good" enough no matter how "cheaply" Airbus may sell it because of lower RD costs.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 6:11 pm
by Taxi645
Polot wrote:
Your proposed A360-500/600/900/1000 are very similar in size to the 788/789/789/78X respectively. You basically just subtracted 2m from the length, while also (for the 900/1000) added 2m to the wing. The A350-900/1000 ranges are very similar to the 787-9/10 ranges (off by ~200 nm).

Your proposed weights for the variants (175/215T) is probably a tad optimistic.


On the contrary I think they are even conservative. If you look at the dimensions very basically (too basic I know) I propose a circular 5,5m fuselage compared to 5,77 by 5,94m for the 787. If you combine that with the shorter length you already are looking at 16% smaller dimensions. This is even without the significantly shorter range compared to the 787 and the 11% or so improvement in SFC. On the wingspan, this plane would have no category limitation (up to 65m). Therefore I wouldn't exclude further induced drag improvements from leaving the elliptical span loading and going to a larger span at equal wing bending stress.

I think many will be surprised just how low the MTOW on such a A330 replacement would be if launched.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 6:30 pm
by Boeingphan
Is there a reason 8 abreast doesn't work in say a 3-2-3 setting? While middle seats aren't desirable the 2 in the middle seem a bit more tolerable and its fitting more folks than the 2-3-2 setting. Maybe someone has this set up or maybe I'm so far out in left field but it seems reasonable. And while we are on it is 4-4 a non player because of evacuations?

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 6:59 pm
by Newbiepilot
Boeingphan wrote:
Is there a reason 8 abreast doesn't work in say a 3-2-3 setting? While middle seats aren't desirable the 2 in the middle seem a bit more tolerable and its fitting more folks than the 2-3-2 setting. Maybe someone has this set up or maybe I'm so far out in left field but it seems reasonable. And while we are on it is 4-4 a non player because of evacuations?


Airliners.net exaggerates the importance of cabin width in airplane design. The fuselage tube itself is only 10-15% of the weight of the total airplane. Structurally a 2-3-2 is not disastrously inefficient compared to a 6 or 8 abreast design. The majority of the weight of an airplane is the engine, wing, gear, systems and furnishings. We are talking a 1% weight penalty max on having a 2-3-2 cabin width. The people inside of the plane weigh more than the fuselage structure does.

They key design features are the payload, empty weight and max takeoff weight. Those weights determine wing size and engine size. From there different fuselage widths and lengths can be considered.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 7:17 pm
by seahawk
Taxi645 wrote:
seahawk wrote:
One wonders how you would find a 20% reduction in OEW over the 787, while offering similar size and range...


Why would it have similar size and range? That's more the A350 role. If you're aiming for more differentiation to the A350 is doesn't make sense basing it on the capabilities of an even more capable plane than the A330, the 787. The A330 replacement doesn't need the size nor range of the 787 and, as Polot say's, can make use of GTF and other SFC improvements. I think the smallest possible diameter 8-abreast that still accepts LD3's would make sense.


Your A360-900 proposal is very similar to the 787-8 in range and capacity.

william wrote:
A shrink has never been a marketing success in the past, and all of a sudden it will now? Especially against a new platform? And depending on what Boeing comes up with, this shrink may not be "good" enough no matter how "cheaply" Airbus may sell it because of lower RD costs.


Yes, a shrink never sold to well in the past, but currently the A330 would be the only option in that size range and if the demand is so huge, why no airline ever pushed Airbus for a A330 light, instead the MTOW went up and up.

Apart from that I am always surprised, when people come to the conclusion that it would be totally awesome if Boeing or Airbus would built a new plane and trade even more seating comfort for efficiency. Everybody here heavily invested in airline stocks? I personally would be very careful designing something with less than 17.5" seat width and less than 18" aisle width, because the risk of a regulation for minimum seat comfort is increasing. And you would look very stupid if your 17" seats at 2-4-2 turn into 2-3-2 due to legislation requiring 17.5" seat width.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 7:32 pm
by kurtverbose
The gap isn't A320 to A330. By the time a new aeroplane comes along (8-10 years minimum) the A330 will be on its last legs. The gap is A320 (or A322 as it probably will be by then) and A350neo

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 7:41 pm
by flipdewaf
Newbiepilot wrote:
Airliners.net exaggerates the importance of cabin width in airplane design. The fuselage tube itself is only 10-15% of the weight of the total airplane. Structurally a 2-3-2 is not disastrously inefficient compared to a 6 or 8 abreast design. The majority of the weight of an airplane is the engine, wing, gear, systems and furnishings. We are talking a 1% weight penalty max on having a 2-3-2 cabin width. The people inside of the plane weigh more than the fuselage structure does.

They key design features are the payload, empty weight and max takeoff weight. Those weights determine wing size and engine size. From there different fuselage widths and lengths can be considered.

While you are correct that the fuselage weight only constitutes ~10% of the weight that level stays constant as a ratio so if you increase the weight of the fuselage by 10% then the overall weight for the aircraft only increases by 1% if you are willing to accept a performance reduction, if you want the performance to remain (payload range) then the rest of the aircraft needs to increase too. If anything I think the fuselage/cabin is still under played, its just a.net likes to play 17vs 18 inches far too much.

Fred

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 8:08 pm
by TWA772LR
flipdewaf wrote:
Newbiepilot wrote:
Airliners.net exaggerates the importance of cabin width in airplane design. The fuselage tube itself is only 10-15% of the weight of the total airplane. Structurally a 2-3-2 is not disastrously inefficient compared to a 6 or 8 abreast design. The majority of the weight of an airplane is the engine, wing, gear, systems and furnishings. We are talking a 1% weight penalty max on having a 2-3-2 cabin width. The people inside of the plane weigh more than the fuselage structure does.

They key design features are the payload, empty weight and max takeoff weight. Those weights determine wing size and engine size. From there different fuselage widths and lengths can be considered.

While you are correct that the fuselage weight only constitutes ~10% of the weight that level stays constant as a ratio so if you increase the weight of the fuselage by 10% then the overall weight for the aircraft only increases by 1% if you are willing to accept a performance reduction, if you want the performance to remain (payload range) then the rest of the aircraft needs to increase too. If anything I think the fuselage/cabin is still under played, its just a.net likes to play 17vs 18 inches far too much.

Fred

I still think the MoM can be done at 7-abreast with CFRP. The weight savings compared to aluminum should offset the drag brought about by the extra seat and aisle. If not, do an A310-sized aircraft and call it a day.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 8:29 pm
by 77west
I think the need to fit the same containers as the A330/787 and up will be taken into account as well. Either the narrowest possible 2-3-2 that fits LD3, or again narrowest 2-4-2 which is basically A330 width. Any narrowbody much longer than the 757-200 suffers from boarding issues. Perhaps a narrowbody with an aisle 50% greater than normal to allow two people to pass each other would work.

The MoM will really need to cover the 220-300 seat mid range market so I just don't see narrowbody working long term.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 8:45 pm
by Theseus
Newbiepilot wrote:
Airliners.net exaggerates the importance of cabin width in airplane design. The fuselage tube itself is only 10-15% of the weight of the total airplane. Structurally a 2-3-2 is not disastrously inefficient compared to a 6 or 8 abreast design. The majority of the weight of an airplane is the engine, wing, gear, systems and furnishings. We are talking a 1% weight penalty max on having a 2-3-2 cabin width. The people inside of the plane weigh more than the fuselage structure does.


Sorry if I am missing the obvious (I am no expert, this is no criticism or argument really), but I would actually read this the other way around: the weight gap from 7 to 8 abreast seating is low, and buys 15% more capacity (at least in Y), so the penalty of the 7 against an 8 based only on relative capacity and weight advantages the 8 abreast quite a bit. What am I missing ?
(of course, this is considering just weight and capacity, and ignoring aerodynamics ---wider must incur a larger penalty there, I would expect a square factor of the width gain--- and dimensioning of other systems, wings, engines, etc that the larger plane requires).

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 8:51 pm
by william
kurtverbose wrote:
The gap isn't A320 to A330. By the time a new aeroplane comes along (8-10 years minimum) the A330 will be on its last legs. The gap is A320 (or A322 as it probably will be by then) and A350neo

Yeah, that's I stated if Airbus does do this it will be as a 330 replacement. To give more market separation from the A350 it will be narrower and much lighter. So Airbus will be working with the MOM being the base working up. While Boeing's plane will be MOM at the top of the range working down, trying to tie this into a 737 replacement.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 9:57 pm
by Planesmart
william wrote:
So Airbus will be working with the MOM being the base working up. While Boeing's plane will be MOM at the top of the range working down, trying to tie this into a 737 replacement.

Well summarised.

Boeing will have difficulty pinpointing 'the' market, to satisfy internal financial criteria for a new model launch, and achieving specific 788 and 777X family targets. Airbus will be waiting.

Boeing are talking to customers to try to create consensus and groundswell enthusiasm. Tying it into a 737 replacement gives the two projects more traction, make it more likely one will be approved, and perhaps encourage an earlier Airbus move.

If the Boeing board said you can do a 737 replacement or a MOM, not both, which way would they jump?

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 10:50 pm
by jagraham
Getting a widebody to within a couple of percent of a narrowbody of same cabin floor area is possible. But the physics can't be avoided.

First, weight matters. So it's virtually impossible to build a tube and wing with the same engines and MTOW with a significant increase in fuel economy without a significant diet. 1a is that the for a certain payload the fuselage must support the structure. So if the designers did a good job with the A330 or 787, there's not much weight savings to find in the fuselage. Add in newbiepilot's observation that fuselage is 15% or so of total weight, and it would appear that there is not much gain to be had in totally redoing the fuselage. Lighter skin panels might be worth it, but that's about it.

Second, fuel consumption is not just fuel efficiency. It's fuel efficiency times thrust. If the Trent XWB is 10% SFC better than the Pratt GTF (not saying that's the case, just making an example), but has twice the thrust, the Pratt GTF will burn about 40% less fuel on an absolute basis. Not to mention the weight difference.

So the key is to make a GTF or LEAP work in the application.

Early 767-300s and A300s had engines with less than 50000 lb thrust, and were transatlantic in range. So the base airplane should be doable in 767-300 to A300 size. With regards to the 767, there were airport constraints (LGA with 7000 ft runways and gate size limits) that compromised even a 1970s wing. Wingspan has grown since then and airports accommodate A330 wingspans easily. Also, Airbus A330 CEO needs over 9000 feet takeoff distance when fully loaded, and that is alright with airlines today.

So first is big wingspan. And since Cd is a direct factor of aspect ratio (everything else being equal, 10% higher aspect ratio gives 10% lower Cd ( https://www.grc.nasa.gov/WWW/K-12/airplane/induced.html ). The A330 has 197 foot wingspan vs 767-300 156 ft, or 26% greater wingspan. Which gives about 25% better aspect ratio - and 25% better Cd - right there.

So the MOM should have as long of a wing as they can get away with.

Next is wing area. For a given wing length, less area increases the aspect ratio. So the designers should shrink the wing, and particularly the root chord, as much as they can.

Then there is fuel. An A321 starts with about 7000 gal. Leeham says eachi ACT adds 2.4t (about 800 gal) fuel. So 3 ACT gives 9400 gal Leeham also says the A321neoLR can fly 52t 4000nm with this configuration (if eacih passenger with bags weighs 220 lb, 200 passengers and bags is 44000 lb or 20t. The fuel weighs 28.2t, so that leaves 4t or so for cabin equipment and catering. No cargo. Bags are bulk loaded. It's questionable, and Leeham alludes to that, but I will leave it as is.

Prorated, 220 pax should be at about 31t (10185 gal) and 250 pax should be at about 35.25t (11574 gal). The 767-300A carried 16000 gal and the A300-600 18000 gal. Each would need to get by on about 6000 gal less to be equal to the A321neoLR.

The 767 wing box fuel tank holds 8000 gallons. The A330 wing box fuel tank holds 12000 gallons. So to increase aspect ratio, the wing box becomes the primary fuel storage. It should be enough for the A330 if the other requirements can be met, while the 767-300 would need 3000 gallons (vs 16000 currently) in the wings. So the last spar could be removed and the wing area reduced by 20%. For the A330 that's a 12% reduction in drag. For the A300 (with the A330 wing box) the L/D improvement might be 30% or more. Which suggests 43000 lb thrust (down from 48000 for GE CF6-80A on 767-300). So a new wing could reduce thrust enough for this to work.

What about weight? The A321neoLR is 97t. Proportionally, the 220 pax (767-300) would need to be 107t, and the 250 pax A330 would need to be 121.25t. The 767-300A is 159t, and the A300-600 is 172t. So the 767 would need to lose about 42t, and the A300-600 about 51t. But there's another way to look at it. The OEW of the A321ceo is 48.5t. Add 4t for the heavier neo engines and 2t for the 3 ACTs and hardware, and the A321neoLR should be about 54.5t. (Leeham says the A321neoLR needs an OEW of 52t to work, but without weight savings elsewhere, that won't happen - probably MTOW will end up being 100t, but that's just my opinion). Proportionally, the 767 needs 61t OEW, and the A300-600 needs 68.2t The 767 is 82t and the A300 is 89t. Each needs to lose 21t. Engines go from 9200 lb to 6000 lb (GTF) each, a reduction of about 3t. About 2t can be taken out of structure due to less weight and less thrust. If the wings are 40% of the weight, and they are reduced by 25% of area, that's a 10% weight savings, 8.2t in the 767 and 9t in the A300. So the 767 is 13t lighter and the A300 is 14t lighter. Still have to find about 6 to 7 tonnes. But that 6 to 7 tonnes equates to a 3% to 3.5% fuel economy miss. And the payload margins have not been changed. These hypothetical aircraft may be able to fly their original payloads of 55t for the 767 and 50t for the A300. Versus 42t for the A321neoLR. So if we assume the A321neoLR payload is sufficient, these hypothetical aircraft should be able to fly the A321neoLR payload farther, or fly more payload the same distance.

Maybe the widebody MOM aircraft isn't so farfetched after all.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Fri Apr 21, 2017 11:11 pm
by william
No not so farfetched really, the widebody MOM will have to have more in common with a 737 replacement to make the numbers work than heavier A330 like aircraft.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 9:04 am
by WIederling
Newbiepilot wrote:
I'm not the biggest fan of a.net doctrine, but that is correct. The A332 was a popular shrink but probably because the A333 was underpowered with low MTOW at the time.


A332 shrink was the perfect decision for Airbus at the time. ( At its best time the A332 strongly dominated A330 deliveries.)
while Airbus waited for better engine sfc and little thrust bumps that would complement increasing MTOW over time.

The A332 exceeded that "magic range" for increased attractiveness that the A333 achieved some years later.

You see the same kind of growing process active on the A320 family.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 9:57 am
by parapente
It's worth rembering that this so called MOM 'gap' is a Boeing invention.Just saying it does not mean it exists.The reason they raised it at all is because of the A321NEO and the LR version in development.All the US majors are either buying it or very interested in it,along with many other carriers around the World.Boeing can hardly come out and say 'well done you got it spot on' can they.
Range.There was a recent article (will try and find) that put a 4knm radius range map on top of key cities.New York,Miami,Delhi and another (as I recall).What it shows is the 4knm from these key airports covers just about everything of importance.NY both trans con and tatl.Miami all key South American cities,Delhi all of far/Middle East.
But Boeing says no its 4,500nm.No doubt the extra 500nm would be nice but it's clearly not critical.
Pax.The A321NEO with the latest seats,interior and galleys etc can fly any thing between 240-200 pax depending on config/range.I believe it's 206 for the LR at 4knm.
Boeing says it needs to be bigger.But does it?Its a little more than the 752 and that was thought to be fine.We know what happens if you go much bigger.Its the 332 and that ain't selling (nor is the 788).So the A321NEO can't be that far off being right,particularly if you look at sales!

Finally there is price and timing.The airlines want 'soon and cheap' again that sounds like the A321NEO not a 12$bn MOM with no existing engines.
Lot of Boeing smoke and mirrors methinks.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 11:27 am
by Newbiepilot
Airbus has a big gap between the A321 and A330. The A330 wing is three times larger and carries a MTOW 2.5 times higher than the A321. The discussion of widebodies being inefficient compared to narrow bodies is because today all the widebodies have giant wings and over powered engines. Derating the engines doesn't help much. There is no question that Airbus has a gap. The question is, do they want to fill it?

Theseus wrote:
Newbiepilot wrote:
Airliners.net exaggerates the importance of cabin width in airplane design. The fuselage tube itself is only 10-15% of the weight of the total airplane. Structurally a 2-3-2 is not disastrously inefficient compared to a 6 or 8 abreast design. The majority of the weight of an airplane is the engine, wing, gear, systems and furnishings. We are talking a 1% weight penalty max on having a 2-3-2 cabin width. The people inside of the plane weigh more than the fuselage structure does.


Sorry if I am missing the obvious (I am no expert, this is no criticism or argument really), but I would actually read this the other way around: the weight gap from 7 to 8 abreast seating is low, and buys 15% more capacity (at least in Y), so the penalty of the 7 against an 8 based only on relative capacity and weight advantages the 8 abreast quite a bit. What am I missing ?
(of course, this is considering just weight and capacity, and ignoring aerodynamics ---wider must incur a larger penalty there, I would expect a square factor of the width gain--- and dimensioning of other systems, wings, engines, etc that the larger plane requires).


What it means is the actual dimensions of the cabin are not all the critical in the overall weight of the airplane. The lifting capability of the wing and engines is defines how much payload (passengers and fuel) the plane is designed to be carried. The actual fuselage cross section and dimensions aren't that critical (it could be a long 6 abreast like a 757-300 or short 8 abreast like an A310 or in the middle like a 767). With he fuselage just 10% of the weight, a 10% bigger cabin only increases the airplane weight by 1%. Fuselage dimensions are not what is critical. What is critical is how much payload needs to be carried (passengers, baggage and fuel). There can be a shorter passenger cabin that has more fuel or a longer passenger cabin that has less fuel equally well optimized for the engine and wing combination.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 11:54 am
by YIMBY
I do not expect any new clean-sheet aircraft by Airbus in the near future (unless a 100-130 seated turboprop). What I would expect is new wings, that is, a larger wing for 321 and/or a smaller wing for 332. Of course, with some mission creep both may transform to completely new projects.

I predict, however, that Airbus will not announce anything MoM-like before Boeing moves first.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 1:14 pm
by flee
YIMBY wrote:
I do not expect any new clean-sheet aircraft by Airbus in the near future (unless a 100-130 seated turboprop). What I would expect is new wings, that is, a larger wing for 321 and/or a smaller wing for 332. Of course, with some mission creep both may transform to completely new projects.

I predict, however, that Airbus will not announce anything MoM-like before Boeing moves first.
I think that both the A320 and A330 have yet to exhaust their development potential yet. Boeing has managed to keep the B737 going with successive fuselage stretches, new wings and new engines.

So, Airbus could take a page out of Boeing's playbook. They have NEOed the A320/330 - so the next logical development is completely new CFRP wings for them with new or developments of the existing NEO engines.

Airbus has already shown off their prototype CFRP wingbox last year - so they are thinking along those lines already. Maybe that CFRP wingbox will go into a new A321 or A322 with new CFRP wings with little or no weight penalty.

I would not be surprised if the Airbus MOM/NMA effort will be similar to what Boeing did a few decades ago with the B757/767. It won't be a bad idea to have rewinged and reengined A320/330s optimised for different airline mission preferences.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 1:22 pm
by VS11
I don't believe that a widebody MOM is a winning concept. MOM has to be narrowbody to be economical. How further can the A321 length be extended? Longer A321 seems to me to be the low-hanging-fruit answer.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 1:52 pm
by frmrCapCadet
A hunk of Boeing's gap is the 787's unexpectedly high production cost. Take off the $30 million extra for previously high production, and perhaps as much for what Boeing expected for ultra-efficient production and that 787-8 would a challenge not only to the 330neo but also to many 321s.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 2:06 pm
by Clipper101
parapente wrote:
It's worth rembering that this so called MOM 'gap' is a Boeing invention.Just saying it does not mean it exists.The reason they raised it at all is because of the A321NEO and the LR version in development.All the US majors are either buying it or very interested in it,along with many other carriers around the World.Boeing can hardly come out and say 'well done you got it spot on' can they.
Range.There was a recent article (will try and find) that put a 4knm radius range map on top of key cities.New York,Miami,Delhi and another (as I recall).What it shows is the 4knm from these key airports covers just about everything of importance.NY both trans con and tatl.Miami all key South American cities,Delhi all of far/Middle East.
But Boeing says no its 4,500nm.No doubt the extra 500nm would be nice but it's clearly not critical.
Pax.The A321NEO with the latest seats,interior and galleys etc can fly any thing between 240-200 pax depending on config/range.I believe it's 206 for the LR at 4knm.
Boeing says it needs to be bigger.But does it?Its a little more than the 752 and that was thought to be fine.We know what happens if you go much bigger.Its the 332 and that ain't selling (nor is the 788).So the A321NEO can't be that far off being right,particularly if you look at sales!

Finally there is price and timing.The airlines want 'soon and cheap' again that sounds like the A321NEO not a 12$bn MOM with no existing engines.
Lot of Boeing smoke and mirrors methinks.


That is possibly the Leeham article & configuration that you are referring to ! Their (Leeham’s) 206 layout count considered a 30-inch pitch in the economy, taking the pitch up to 32-inch should bring seat count down to around 190 at best. Since the configuration was made using an A320neo SpaceFlex concept and since we are talking an LR version of the A321neo, then we would expect a demand on catering, cabin stowage and lavatory. All above would see an A321neoLR around 180 (plus-minus).

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 2:25 pm
by Revelation
To me the most significant piece of data we have is:
seahawk wrote:
2. the market segment assigned to the MoM is anything but uniform. Reaching from less than 200 seats with 5000+nm range to more than 300 seats and less than 3000nm range.

The founder of IBM said 'it all starts with the sale'. There's little use building something that won't sell in sufficient numbers to support its investment. So many factors already cited here make it difficult to see the business case close, but to me this is the biggest one -- the market isn't clear about what it wants, and Boeing can't afford a speculative investment.

parapente wrote:
Lot of Boeing smoke and mirrors methinks.

I suppose that's one way of looking at it. The thing is, other than a few big press blasts a few months ago, Boeing really isn't going out of its way to talk it up. It's just that every so often someone here brings it up, and we have yet another inconclusive discussion.

Re: Airbus MoM / NMA / A310 replacement, 2025?

Posted: Sat Apr 22, 2017 2:46 pm
by seahawk
william wrote:
No not so farfetched really, the widebody MOM will have to have more in common with a 737 replacement to make the numbers work than heavier A330 like aircraft.


What exactly will the NSA have in common with the MoM?

frmrCapCadet wrote:
A hunk of Boeing's gap is the 787's unexpectedly high production cost. Take off the $30 million extra for previously high production, and perhaps as much for what Boeing expected for ultra-efficient production and that 787-8 would a challenge not only to the 330neo but also to many 321s.


That is imho one of the big problems for Boeing. To be competitive on performance they need bleeding edge technology and as we know from the customer survey airlines are not willing to pay much over 90 millions. But if you can bring 767-300 sized plane with 5000nm range and A321 like CASM, it is superior competitor to the 787 as long as you do not need more range. But then 5000nm is plenty and surely enough for most 767 users, who so far are seen as likely 787 customers by Boeing. So how do you sell as many 787 as they need to sell for the price they need to achieve? And with every 787 not sold, they need to achieve a higher margin for the rest.