Newbiepilot wrote:

This picture is why I think the A320neo Supply chain is more complex than the 737

The supply chain, for any aircraft including A320 or 737, is a long chain of tiered suppliers providing structural components as well as a myriad of pipes, ducts, brackets, avionics components, pumps, valves, fans, harnesses etc...All managed in configuration, tested and qualified, and shipped from all over the world. That is where the complexity lies.
This is just the tail end, and its focus on structural parts misses that fact that these sections are actually pre-equipped modules which will come together at the FAL...just like the 787 !
So what the diagram actually means is that instead of hundreds of thousands of parts converging onto a single FAL location, the supply chain is effectively split into several sub-chains with little overlap. This would actually tend to simplify management of operational variabilities, and avoids creating a mega logistics chocking point at the FAL

It seems that subsequent posts are on this theme as well : systems installation is likely equivalent to structural assembly in terms of driving lead times, man-hours, specialist tooling and critical paths. In some cases it may have become the only driver. I would suspect that procurement costs are still driven by the massive structures made of expensive materials, but the costs of qualified system components are probably not that far behind.
So going forward, "streamlining production processes" is most likely a heavy work on system design and installation within the structure, rather than pure structural design considerations.

Which is why I join Astuteman in saying that this discussion about barrels vs panels is fairly meaningless. And it cannot be considered only from a structural point of view, as systems considerations may be important drivers as well (high power/high voltage electrics, fiber optics directly integrated into the structure, combined structure/system modules...)

2175301 wrote:

Using end of year and 4th quarter 2017 numbers: Boeing had and outstanding deffered and unamortized tooling cost of $28,531 Billion (if I added correctly), and 658 orders. This would be about $43 million per remaining aircraft. Looking at the 3rd to 4th quarter reports on Deferred and unamortized cooling cost Boeing reduced such cost by $751 million with 36 deliveries (and average of $20.86 million per aircraft if I did my math correctly).

And that right there may be the reason why Boeing became so aggressive. I had not realized that the deferred costs/plane had been rising so much. If Boeing wants to avoid a forward loss, it makes sense to sacrifice a bit of revenue (they have lots anyway) to extend the accounting block and spread those costs as much as possible
[I'm not being negative, this just seems to be a reasonable strategy given the constraints of program accounting]

2175301 wrote:

My point is that they have potentially learned how to produce a much less costly barrel in the process of making 600+ of them for the 787

But Boeing has not necessarily revolutionized manufacturing costs, the 787 is now simply back on to its predicted "permanent regime", with costs 15-20M$ under the predicted average cost of production for the program accounting block.
All based on a production method which is by and large similar to the Airbus one, except for the minor point that they skip the step of assembling panels into a fuselage section. So I doubt that when predicted production costs were first presented to auditors at the start of the program accounting, the auditors would accept cost predictions significantly different from what could be seen at Airbus.

To be clear I'm not trying to piss on the great efforts and innovations pushed by Boeing on the 787 lines, on the contrary I admire some aspects of it due to my own experience. It's just that there is a lot of talk here, based on some perceived idea that production methods for the 787 are never-seen-before and result in significantly lower costs than for any other aircraft, and that this could be directly carried over to the potential 797. Yet I really do not see any real-world indication that this can be true, and most of the justification here is based on just pumped-up arguments based on only 2 sale campaigns and a fairly meaningless discussion about barrels vs panels.
Now if anyone here were to tell me that Boeing has implemented a fully digital, model-based design with virtual pre-testing and operational simulations, then yes, I'd be willing to accept that they have a good chance of doing something remarkable with the 797. Information management and communication is where the opportunities lie.

OK last post, I'll get back to work now

275 NEO's have been delivered so far. The 8,000th A320 (Tianjin, PW powered) a few weeks ago.

If we consider the A321NEO Plus a stretch of the A321 and the A321 NEO Plus-Plus as having a new wing, I really can't see those folks now looking at new Plus Plus wing configurations being shifted to help resolve the engines delivery problems. This is not your typical local bakery with people giving a hand to catch up

keesje wrote:

If we consider the A321NEO Plus a stretch of the A321 and the A321 NEO Plus-Plus as having a new wing, I really can't see those folks now looking at new Plus Plus wing configurations being shifted to help resolve the engines delivery problems. This is not your typical local bakery with people giving a hand to catch up

Back in Reply #85 we had:

Polot wrote:

mjoelnir wrote:

Regarding moving engineering assets to the A320 family ramp up problems. The main problem seems to be engines. That are things that have to be done at the engine manufacturers. How would one use Airbus engineering assets to speed up the work at the engine manufacturers?

Correction: the main problem at the current production rate seems to be engines. Airbus wants higher production rates. Rates higher than they have ever produced before. Just because Airbus can build A320s smoothly at the current rate (we will ignore engines) doesn’t mean there are not challenges in increasing the rate that need engineering resources to solve. An increased production rate can introduce an entirely brand new rate limiting step.

Shortly before that post, Airbus announced the new rate of 63/month in 2019, so I can see how this isn't just an engine problem they are addressing.

On the other hand, I too have raised the point that it doesn't seem that plausible that shifting engineers working on new product development to manufacturing would be helpful, but there was some push back on that idea.

This could all be an exercise in information warfare and/or public relations.

JoeCanuck wrote:

IF Boeing decided to switch to panels for a new plane, that doesn't automatically mean that barrels were a mistake on the 787. All it would mean that barrels were optimum then, and something better may have come along in the meantime.

Now, I'm not saying Airbus's panel method is ideal either. CFRP techology is advancing every day, so neither method may be the best idea for the next gen aircraft.

While it certainly would not be a good idea to switch formats on existing production lines, if you're building a new line, it may be more efficient to incorporate the newest technology available.

Maybe I was being a little too provocative...

I agree that it's possible that panels could turn out to be a better solution for NMA where barrels were an optimal solution for the 787... but I think it would have to be a really big difference to make a method switch compelling. Either that or barrels were not as advantageous as they originally thought.

Note I'm not saying anything slanderous here, it's perfectly feasible - and okay - to develop a technology and then decide an alternative might have been as good or better.

Regarding barrels vs panels shouldn’t we consider development and mfg cost separately.

For panels, each individual component requires separate supply chain and tooling investment.

For barrels it’s seems to me the situation on the next plane is so much more elegant.

I’d love some input from those who industry experience.

I think it is too early to say the 797 will have a CRFP fuselage as far as I can see.

It's not like the Al supply chain & production technology suppliers have been sitting on their hands for the last 25 yrs.

Boeing’s latest 777-9 will have composite wings but will sport a mostly aluminium fuselage The reason for this change is the emergence of advanced third generation aluminium-lithium (Al-Li) alloys, which are not just cheaper than both CFRP and titanium alloys, but are also lighter and stronger than previous iterations. As a result, Al-Li alloy-intensive aircraft have better fuel efficiency and lower maintenance costs.

In terms of processing, costs, maintenance and mechanical properties metals might be tun out (again) as the best option for the fuselage. Maybe AlMgSc (AA5028) turns out cheaper & lighter the carbon fibre for the narrower fuselages..

https://aluminiuminsider.com/aluminium-lithium-alloys-fight-back/

Now back to topic.. ok, let it go

Planeflyer wrote:

Regarding barrels vs panels shouldn’t we consider development and mfg cost separately.

For panels, each individual component requires separate supply chain and tooling investment.

For barrels it’s seems to me the situation on the next plane is so much more elegant.

I’d love some input from those who industry experience.

Panels can be made everywhere on cheap tooling / moved around in the belly of every wide body.
Barrels in huge autoclaves / Dreamlifters only. Think about that .. $$ ..

Again, Airbus has a very large 320neo family backlog, reducing costs, improving delivery schedules, ramping up production has a huge profit potential. Competing with a potential MOM will come, they will have the cash to easily do it, and pay dividends. Boeing will have an advantage on the MOM for a few years. So what? Two companies can't have the same particular advantage at the same time.

Revelation wrote:

On the other hand, I too have raised the point that it doesn't seem that plausible that shifting engineers working on new product development to manufacturing would be helpful...

Why wouldn't it? Developing new processes, parts, tools and techniques can help improve on efficiencies needed to push current aircraft production rates higher. Airbus already invests many millions of dollars every year in continuous improvement of their existing line up, not only in adding value to their products but also improving production processes. This shift in engineering resources could well mean that they want to explore more opportunities in helping bring down the backlog faster.

I recall (but couldn't find out for sure) that Airbus has 3 primary assembly lines for the A320, not sure how many lines and jigs for structures there are. Boeing I think has 2 main lines + the P-8 line that also can build commercial planes. Back a decade ago Boeing changed the 777 line from the previous fixed position to a moving line, besides for cost B had found that the fixed line was limited to about 7 planes a month. Similarly the NB lines have an original design rate. Bumping that rate and going above means that the critical path at each station needs to be sped up, that is often quite tough as the jigs are set up to perform specific tasks so adding manpower doesn't really speed up things appreciably. Going to 3rd shift and working weekends maximizes the hours a line operates a week, but with lunch, breaks, and shift changes the 3rd shift only adds like 6 hours of production.

Airbus may need to build another line to complete the major pieces that ship out to Alabama or China in order to get the rate increase. That is expensive but may be the only way to speed up the total rate. The 787 has two lines with about 8/month capacity on each line. In the NB's a line probably tops out at about 25 per line per month.

Getting a line producing all one model (say A321) eliminates nearly all changeover from one plane to the next. Airbus focusing on only the current models in production maximizes the output.

With the extensive backlog and taking 55% of the NB orders allows it to defer any review until a few years after B launches the MOM, possibly even 5-6 more years before they tackle the NB replacement. So best to optimize the current production for several years.

If by temporarily delaying action on the + and ++ models, A can increase output and decrease cost this is a very good move.

After all it seems they have time to respond assuming B launches the 797.

I happen to think B will, in part because the barrel concept facilities new designs at lower cost.

IMO market forces will decide. Before the Plus Plus came up Leahy was strongly denying any need for a bigger A321 "for now"

And then the situation changed. Longer term research in general isn't driven by day to day communication of executives.

On a Plus Plus, it would most likely have a bigger wing, wingbox etc.

That might justify a dedicated FAL at one of the 4 locations, most likely Mobile or Hamburg. Unless the Chinese start waving with a proposal A can't refuse.

I've been wondering what would be the smallest possible Plus Plus wing that could do the job. I guess requirements could be:
- adding 500NM extra range to the A321LR
- getting rid of 2 ATC's out of the 3 in the A321LR fuselage
- adding significant capacity/ space for seats /crew rest/ galley/ lavatory
- 2 meters aft the wing, 3 meters before.

The smaller, lighter, the better. It has to be lean enough for 270 seat single class 2-5 hour leisure / LCC flights too, inter hub in Europe, US Eastcoast and Asia.
Earlier on, I concluded a ~30% bigger wing tank capacity, with a roughly similar wing setup would result in a ~10-12% bigger wingspan.



Keeping it within ICAO Reference Code C seems impossible, but limiting wingspan to ~41m might enable modifying / certifying many code C gates for it, without having to go for more costly reference code D modifications.

Elementalism wrote:

Right now the LR does about 90% of the 757, a 40 year old design. So I would expect the 797 to bring forward efficiency. Meaning I wouldnt expect the LR to really be 90% of a 797 when all is said and done.

As for the rest. Anything is possible. Boeing could also give it away for free. What we do know is Boeing believes it is a 4K frame market, not 1k. History has shown the 757\767 are ~2400 frames in a different time in aviation. And the A330 is the size of a 787. The A330 Neo isnt exactly lighting it up vs the 787. It will not be able to compete with the 797 imo. Too expensive, too big, too much plane, too expensive to run.

And I don't expect this to cost 20 billion. A lot of the R&D for this was done with the 787 program. Now they need to take that and build a clean sheet MoM aircraft in the ~300-350,000 pound MTOW range that can do 4500-5000nm with 230-250 pax.

1. A twin aisle A/C will never be more efficient than a single aisle
2. where would this "new technology" come from to surpass a single aisle A321neoLR?
3. Boeing needs to recoup the R&D cost. If it is 10B$ or 20B$ doesn't matter it puts them at a disadvantage right out of the gate
4. yes, of course the A330 is too big. But if it is only used for certain routes (those the A321neoLR cannot do) it will only be too big (and to costly to operate) on those few routes.
THIS is what Airbus can offer to compensate either by offerering a dirt cheap price (R&D for A330 is long written off) or a discount on the A321s etc. as long as you can keep Boeing from selling 1000s of MOMs....

To say that a twin aisle can never be as efficient as a single is plainly wrong.I am sure you meant over short sectors?
There clearly are crossovers which will depend on the aircaft in question.
As has been said many times the present A320 wing is optimised for short trips ( and indeed has a lower optimism speed).It is not an optimum wing for 3-4 knm.Clearly the 797 wing will be optimised for this sort of trip(s) distance (3-5 knm).Yes a twin aisle is more draggy -but by how much?We don't know ,but that is why there has been so much talk about complex lower drag ovoid shapes.The better wing may well overcome the drag penalty.
Also on the ort of trip length envisaged the 797 will be taking more pax and more cargo (A321LR is zero cargo)further.All these factors have to be put into the efficiency equations.
Over shorter distances as stated the narrow body rules.So no surprises that Airbus has been discussing improved shorter range 'plus' models with fully optimised 200 and 250 seat arrangements.They will surely come when they have got their production backlog issues sorted.It should prevent the 797 'creeping down' the range spectrum.Caveat single vs twin disembarkation times might be an issue but I doubt it.
However above 250 pax - and one 797 model is clearly above (260-270 pax 2 class?) -then if you have short 'thick' routes then this would be your choice.Yes you can super stretch narrow bodied a/c to this size (753) but they are a nightmare to board and exit.

with more efficient I was not refering to drag etc. but to yield.
If you want to transport 200 people in a single aisle the trip costs at lot less (total and per passenger) as with 200 people in a twin aisle aircraft.

.
I think Airbus hopes Boeing goes in with a real capable 797 twin aisle, the bigger and more capable, the better.
Keeping pushing around 737s in the enormous <260 seat < 3000Nm segment.

Twin aisle fuselage diameters might enable standard cargo containers to be stored in pairs in the lower deck. That can be a major income source besides the passengers.

bigjku wrote:

I think the engineering moves around the A320neo are about finding any and all ways to produce it more cheaply. Fundamentally it makes sense. Any improvements on the current base are only going to increase cost. If you find out that you don’t have the space costwise to play with step 1 is to drive down your current cost then see what you can add to it.

I dug this up from ST: Lynnwood engineering firm to design Airbus assembly line

It says:

For this fourth A320 production line in Hamburg, Nova-Tech will provide all the equipment to move and position aircraft components, to align and join fuselage sections, and to align and join wings to the fuselage.

Bill Bigot, Nova-Tech’s vice president of marketing and business development, said the design is very different from the existing assembly lines, using mobile tooling instead of fixed monumental equipment.

Airbus “wanted a step change,” Bigot said. “It’s not an evolution but a revolution.”

Nova-Tech will supply an integrated system, including drilling robots, an automated logistics system, test equipment, mobile access platforms and hand tools. It will also provide the work orders that instruct mechanics on how to do the assembly.

So, even two years ago, Airbus wanted to massively change how it assembled A320s and hired specialists to help.

Yet now we see even more resources being moved away from A320+/++ design and towards A320 production optimization.

I wonder what that says about earlier efforts to optimize the production line for rate and for cost.

Revelation wrote:

bigjku wrote:

I think the engineering moves around the A320neo are about finding any and all ways to produce it more cheaply. Fundamentally it makes sense. Any improvements on the current base are only going to increase cost. If you find out that you don’t have the space costwise to play with step 1 is to drive down your current cost then see what you can add to it.

I dug this up from ST: Lynnwood engineering firm to design Airbus assembly line

It says:

For this fourth A320 production line in Hamburg, Nova-Tech will provide all the equipment to move and position aircraft components, to align and join fuselage sections, and to align and join wings to the fuselage.

Bill Bigot, Nova-Tech’s vice president of marketing and business development, said the design is very different from the existing assembly lines, using mobile tooling instead of fixed monumental equipment.

Airbus “wanted a step change,” Bigot said. “It’s not an evolution but a revolution.”

Nova-Tech will supply an integrated system, including drilling robots, an automated logistics system, test equipment, mobile access platforms and hand tools. It will also provide the work orders that instruct mechanics on how to do the assembly.

So, even two years ago, Airbus wanted to massively change how it assembled A320s and hired specialists to help.

Yet now we see even more resources being moved away from A320+/++ design and towards A320 production optimization.

I wonder what that says about earlier efforts to optimize the production line for rate and for cost.

It tells us exactly what Airbus have told us. They're serious about it.

Rgds

Good news, one of the priorities is to improve margins and no place better to do it than on the 320 program.

keesje wrote:

.
I think Airbus hopes Boeing goes in with a real capable 797 twin aisle, the bigger and more capable, the better.
Keeping pushing around 737s in the enormous <260 seat < 3000Nm segment.

Is that why you posted this in the 797 development thread?

keesje wrote:

I see a strong drive towards a range of 5000NM or even more for NMA.

IMO that risks building an aircraft that is way to heavy to be competitive on the bulk of flights.

I think it should be optimized, or at least be very efficient for flights of around 2hrs / 1000NM.

Are you hoping Boeing builds an overly capable 797 to protect the market for the A321neo?

Newbiepilot wrote:

keesje wrote:

.
I think Airbus hopes Boeing goes in with a real capable 797 twin aisle, the bigger and more capable, the better.
Keeping pushing around 737s in the enormous <260 seat < 3000Nm segment.

Is that why you posted this in the 797 development thread?

keesje wrote:

I see a strong drive towards a range of 5000NM or even more for NMA.

IMO that risks building an aircraft that is way to heavy to be competitive on the bulk of flights.

I think it should be optimized, or at least be very efficient for flights of around 2hrs / 1000NM.

Are you hoping Boeing builds an overly capable 797 to protect the market for the A321neo?

No, as you yourself quoted

I think Airbus hopes Boeing goes in with a real capable 797 twin aisle, the bigger and more capable, the better.

The A321 seems the bread and butter of their portfolio. Boeing going for the 767 segment would be good news for them.

parapente wrote:

We don't know ,but that is why there has been so much talk about complex lower drag ovoid shapes.The better wing may well overcome the drag penalty.

I wouldn't have an issue with the aerodynamics of a Ovoid being ok but the weight of the thing is the issue (and that drives the size of the wing so the Surface are suffers). The hoop stresses of a larger pressure vessel increase linearly with the diameter and as the surface area increases with the diameter then you have the weight increasing with a higher power of the diameter and so the increase in weight is always bigger than the increase in available floor area.

I cant see an ovoid cutting the mustard for this, the added weight for creating a poor pressure vessel is much better spent on adding LD2 capacity offsetting the small amount of Swet you gain.

Fred

c933103 wrote:

If the advantage of twin aisle over single aisle is boarding and deboarding time, then shouldn't twin aisle be more favorable on short sector than long sector? But why in the real world there are more narrowbodies flying short routes and more widebodies flying long routes?

'cos boarding time is over-rated.

If it were so important, the new A321 cabin wouldn't have the old L2 door blocked up, they'd be using it to board forward and aft, giving a quasi-twin aisle.

flipdewaf wrote:

parapente wrote:

We don't know ,but that is why there has been so much talk about complex lower drag ovoid shapes.The better wing may well overcome the drag penalty.

I wouldn't have an issue with the aerodynamics of a Ovoid being ok but the weight of the thing is the issue (and that drives the size of the wing so the Surface are suffers). The hoop stresses of a larger pressure vessel increase linearly with the diameter and as the surface area increases with the diameter then you have the weight increasing with a higher power of the diameter and so the increase in weight is always bigger than the increase in available floor area.

I cant see an ovoid cutting the mustard for this, the added weight for creating a poor pressure vessel is much better spent on adding LD2 capacity offsetting the small amount of Swet you gain.

Fred

I also have big questionmarks around the avoid shape. The disadvantages seem to richly beat advantages.

A generously dimensioned circular fuselage could offer a hybrid NMA twin/single aisle configuration but also cover the much larger 180-220 seat <1500NM segment in a competitive way.

Cargo capacity would be better than 7 abreast, because for the same seat capacity you have a longer fuselage / cargo deck.



Focussing on full systems, cockpit, fuselage, cabin & tail section identicality, while investing where it make a difference; wings, engines landing gears. To make it real light and practical (ICAO code C gates).

Not cheap but way more efficient than 2 programs.



That would scare Toulouse way more than a carbon 767 from 2026.

Revelation wrote:

I wonder what that says about earlier efforts to optimize the production line for rate and for cost.

First it says
- that building an airliner is difficult
- that building an airliner with good quality is really difficult
- that building lots of airliners with good quality is super difficult
- that building lots of airliners with good quality at (relatively) low cost is mega difficult

...and thus, there will always be new ways to refine the whole process.

It also says that production technology is evolving faster than aerospace technology. And thus that there is more to gain by investing in production than in an all-new airplane if your existing line-up covers the market demand well enough, including in particular the main centers of gravity of said market where thousands of aircraft are being sold.

airmagnac wrote:

Revelation wrote:

I wonder what that says about earlier efforts to optimize the production line for rate and for cost.

First it says
- that building an airliner is difficult
- that building an airliner with good quality is really difficult
- that building lots of airliners with good quality is super difficult
- that building lots of airliners with good quality at (relatively) low cost is mega difficult

...and thus, there will always be new ways to refine the whole process.

It also says that production technology is evolving faster than aerospace technology. And thus that there is more to gain by investing in production than in an all-new airplane if your existing line-up covers the market demand well enough, including in particular the main centers of gravity of said market where thousands of aircraft are being sold.

Thank you for the excellent explanation.

It does make me wonder if it was an organic decision ("there is more to gain by investing in production than in an all-new airplane") versus one influenced by competitive pressures because NSA will come out of the gate with the rapidly evolved production technology therefore Airbus is deciding to make advancements sooner rather than later.

It also makes me wonder what role the 4th XFW line plays in all of this. Was it less helpful than planned therefore a lot of rework is needed? Was it more helpful than planned therefore the manpower will be spent on rolling it out over all the lines? Did it enable a lot of more optimizations and more manpower is needed? Ahh, so many questions...

And, would it or would it not make sense to make such improvements for A330neo, or does it not meet the "main centers of gravity" test? Schulz himself said selling more A330neo is a priority this year. The product seems to be at a crossroad.

keesje wrote:

flipdewaf wrote:

parapente wrote:

We don't know ,but that is why there has been so much talk about complex lower drag ovoid shapes.The better wing may well overcome the drag penalty.

I wouldn't have an issue with the aerodynamics of a Ovoid being ok but the weight of the thing is the issue (and that drives the size of the wing so the Surface are suffers). The hoop stresses of a larger pressure vessel increase linearly with the diameter and as the surface area increases with the diameter then you have the weight increasing with a higher power of the diameter and so the increase in weight is always bigger than the increase in available floor area.

I cant see an ovoid cutting the mustard for this, the added weight for creating a poor pressure vessel is much better spent on adding LD2 capacity offsetting the small amount of Swet you gain.

Fred

I also have big questionmarks around the avoid shape. The disadvantages seem to richly beat advantages.

A generously dimensioned circular fuselage could offer a hybrid NMA twin/single aisle configuration but also cover the much larger 180-220 seat <1500NM segment in a competitive way.

Cargo capacity would be better than 7 abreast, because for the same seat capacity you have a longer fuselage / cargo deck.



Focussing on full systems, cockpit, fuselage, cabin & tail section identicality, while investing where it make a difference; wings, engines landing gears. To make it real light and practical (ICAO code C gates).

Not cheap but way more efficient than 2 programs.



That would scare Toulouse way more than a carbon 767 from 2026.

The Carbon 767 Idea seems to be an Anet creation. Although NMA may well end up being 8W I still think it will end up being 7W as then they can use the Barrel for NSA. Basically NMA will come first but it will be a big wing/wingbox version of NSA. It just makes too much sense. Especially if you only need 5,000NM range - which we are almost there with current Single Aisle's. You don't need to go 8W and LD2's - it will make it way too heavy and you'll never be able to use it for NSA.

Keesje - I've asked before - why wouldn't NMA be an 7W Ovoid big wing version of the NSA - much along the lines of your A322/A323 Studies - weight should be very comparable given that it would be shorter than A322/A323 for the same seating with a 36" wider LD3-45 in the belly for lots of cargo capacity?

How many times have we read that the Skin thickness of a carbon barrel in Single Aisle size is thicker than it structurally needs to be account to account for impact loads - couldn't that extra strength and creative shaping/bracing with the Fuselage frames in the Crown and cargo areas (which wouldn't weigh that much in Carbon) offset the disadvantages of the pressurizing issues of an oval?

Have we not also seen rumours from Boeing sources that they are not actually thinking about a pure Oval? Basically it would be too different circular cross sections joined at the floor beam? The top being sized for the 7W Cabin, with the bottom being a smaller portion of a much larger circle - with the same width as the Cabin but shallower depth. I am not a structural engineer but I would have to guess this would be a lot simpler from a structure standpoint.

morrisond wrote:

keesje wrote:

flipdewaf wrote:

I wouldn't have an issue with the aerodynamics of a Ovoid being ok but the weight of the thing is the issue (and that drives the size of the wing so the Surface are suffers). The hoop stresses of a larger pressure vessel increase linearly with the diameter and as the surface area increases with the diameter then you have the weight increasing with a higher power of the diameter and so the increase in weight is always bigger than the increase in available floor area.

I cant see an ovoid cutting the mustard for this, the added weight for creating a poor pressure vessel is much better spent on adding LD2 capacity offsetting the small amount of Swet you gain.

Fred

I also have big questionmarks around the avoid shape. The disadvantages seem to richly beat advantages.

A generously dimensioned circular fuselage could offer a hybrid NMA twin/single aisle configuration but also cover the much larger 180-220 seat <1500NM segment in a competitive way.

Cargo capacity would be better than 7 abreast, because for the same seat capacity you have a longer fuselage / cargo deck.



Focussing on full systems, cockpit, fuselage, cabin & tail section identicality, while investing where it make a difference; wings, engines landing gears. To make it real light and practical (ICAO code C gates).

Not cheap but way more efficient than 2 programs.



That would scare Toulouse way more than a carbon 767 from 2026.

The Carbon 767 Idea seems to be an Anet creation. Although NMA may well end up being 8W I still think it will end up being 7W as then they can use the Barrel for NSA. Basically NMA will come first but it will be a big wing/wingbox version of NSA. It just makes too much sense. Especially if you only need 5,000NM range - which we are almost there with current Single Aisle's. You don't need to go 8W and LD2's - it will make it way too heavy and you'll never be able to use it for NSA.

Keesje - I've asked before - why wouldn't NMA be an 7W Ovoid big wing version of the NSA - much along the lines of your A322/A323 Studies - weight should be very comparable given that it would be shorter than A322/A323 for the same seating with a 36" wider LD3-45 in the belly for lots of cargo capacity?

How many times have we read that the Skin thickness of a carbon barrel in Single Aisle size is thicker than it structurally needs to be account to account for impact loads - couldn't that extra strength and creative shaping/bracing with the Fuselage frames in the Crown and cargo areas (which wouldn't weigh that much in Carbon) offset the disadvantages of the pressurizing issues of an oval?

Have we not also seen rumours from Boeing sources that they are not actually thinking about a pure Oval? Basically it would be too different circular cross sections joined at the floor beam? The top being sized for the 7W Cabin, with the bottom being a smaller portion of a much larger circle - with the same width as the Cabin but shallower depth. I am not a structural engineer but I would have to guess this would be a lot simpler from a structure standpoint.

Double bubbles have been around for ages, 737, 767, 747 to name a few. For CFRP fuselages. I'm not sure if it would be as effective. Bending moments around the floor seem hard to avoid for a layered carbon skin.

c933103, Varying cross section height is very pratical because of double bubble floor loading, turning it 90 degree would require a vertical load carrying wall in the cabin. Technically possible, but apparently not practical (Airbus P500 concept) http://3.bp.blogspot.com/_-Oqf_vOmanM/SpEWrtulsUI/AAAAAAAAAHU/4PdN0sFL5Tw/s1600/Airbus_P500_concept.JPG

Personally I wouldn't be really surprised if Boeing stays away from CFRP fuselage for this aircraft. Production infrastructure / upfront investment, simplicity of outsourcing, repair and overhaul, questionable weight savings. it has to make sense.What if Al Li pulls forward positive ROI by 6 years?

If NMA could be bigger NSA or the other way around seems sematics if they are initiated at the same time.

morrisond wrote:

Keesje - I've asked before - why wouldn't NMA be an 7W Ovoid big wing version of the NSA - much along the lines of your A322/A323 Studies

Boeing could do that. But then Airbus responds with an identical plane scaled up 10% to allow 8abreast. We then have a repeat of the 767 Vs A330 where Airbus would again outsell Boeing 2 to 1.

No one's crazy enough to go 7ab again. You could just go 8ab and a shorter fuselage using the same technology.

morrisond wrote:

Have we not also seen rumours from Boeing sources that they are not actually thinking about a pure Oval? Basically it would be too different circular cross sections joined at the floor beam?

I came up with that idea and made the graphics for that in Photoshop. They weren't runours from Boeing I made them up out of thin air.

Revelation wrote:

It does make me wonder if it was an organic decision ("there is more to gain by investing in production than in an all-new airplane") versus one influenced by competitive pressures because NSA will come out of the gate with the rapidly evolved production technology therefore Airbus is deciding to make advancements sooner rather than later.

NSA, and even MoM, are just vaporware for the moment, do not have anything close to a converged defintion (it would have leaked via airlines by now), and even if they had, they would each be >10B$ and >10 years away from full stabilized production. Why in the name of all that is aeronatucially holy would Airbus react to such a "threat" ?
Sorry to be brutal, but this is an a-net alternative reality threat, not a real world threat !

Revelation wrote:

It also makes me wonder what role the 4th XFW line plays in all of this. Was it less helpful than planned therefore a lot of rework is needed? Was it more helpful than planned therefore the manpower will be spent on rolling it out over all the lines? Did it enable a lot of more optimizations and more manpower is needed? Ahh, so many questions...

As mentioned before, to increase production rates or improve production in general, you have multiple options which are not exclusive :
1) duplicate assembly stations (such as add a new FAL, or a new sub-station within a FAL)
2) improve assembly processes within an assembly line or a sub-station, by playing with e.g. tooling or sequencing of part installation
3) improve supply chain information flows over the whole value stream from finished product back up to elementary parts (aka 'Lean'). This also includes communication with manuf engineering & design engineering to solve day-to-day issues ("oops I dropped a hammer on the fuselage structure...do we have to throw it all away, or can we push forward ?")
4) change the design of the aircraft to ease the production tasks (for example by making more room within an assembly for assembly personnel to get in and install a part)

Your linked article is an illustration of 1)
The "focus on production" that started this thread is likely going to be a combination of 3) and 4)

And no need to conjure up wild speculation based on the new line, as it is hardly entering service. So its capabilities and impacts cannot be known, much less acted upon...

Revelation wrote:

And, would it or would it not make sense to make such improvements for A330neo, or does it not meet the "main centers of gravity" test? Schulz himself said selling more A330neo is a priority this year. The product seems to be at a crossroad.

Well given its history it is certainly in a popular spot in the market. More than, say, the original 762/763 which dissappeared fairly quickly after the -ERs appeared, which themselves lost steam one the A333 came into being
The question is, is the 787 finally reaching a point where it can do the same to the A330 ? Or is the A330 simply going through a dip in orders due to overall slow market + development issues ? Depending on the answer it may be interesting to invest in the industrial system, or not.
A possible trumpcard is that the A330 architecture is fairly similar to the A320, so maybe synergies can be found and justify carrying solutions from A320 lines over to the A330 FAL.

Revelation wrote:

airmagnac wrote:

Revelation wrote:

I wonder what that says about earlier efforts to optimize the production line for rate and for cost.

First it says
- that building an airliner is difficult
- that building an airliner with good quality is really difficult
- that building lots of airliners with good quality is super difficult
- that building lots of airliners with good quality at (relatively) low cost is mega difficult

...and thus, there will always be new ways to refine the whole process.

It also says that production technology is evolving faster than aerospace technology. And thus that there is more to gain by investing in production than in an all-new airplane if your existing line-up covers the market demand well enough, including in particular the main centers of gravity of said market where thousands of aircraft are being sold.

Thank you for the excellent explanation.

It does make me wonder if it was an organic decision ("there is more to gain by investing in production than in an all-new airplane") versus one influenced by competitive pressures because NSA will come out of the gate with the rapidly evolved production technology therefore Airbus is deciding to make advancements sooner rather than later.

It also makes me wonder what role the 4th XFW line plays in all of this. Was it less helpful than planned therefore a lot of rework is needed? Was it more helpful than planned therefore the manpower will be spent on rolling it out over all the lines? Did it enable a lot of more optimizations and more manpower is needed? Ahh, so many questions...

And, would it or would it not make sense to make such improvements for A330neo, or does it not meet the "main centers of gravity" test? Schulz himself said selling more A330neo is a priority this year. The product seems to be at a crossroad.

Very insightful comments regarding production. I would say keeping up with the supply chain is equally complex. One supplier failing to deliver can stop deliveries. It is constant work keeping that healthy and it requires engineering resources.

keesje wrote:

morrisond wrote:

keesje wrote:

I also have big questionmarks around the avoid shape. The disadvantages seem to richly beat advantages.

A generously dimensioned circular fuselage could offer a hybrid NMA twin/single aisle configuration but also cover the much larger 180-220 seat <1500NM segment in a competitive way.

Cargo capacity would be better than 7 abreast, because for the same seat capacity you have a longer fuselage / cargo deck.



Focussing on full systems, cockpit, fuselage, cabin & tail section identicality, while investing where it make a difference; wings, engines landing gears. To make it real light and practical (ICAO code C gates).

Not cheap but way more efficient than 2 programs.



That would scare Toulouse way more than a carbon 767 from 2026.

The Carbon 767 Idea seems to be an Anet creation. Although NMA may well end up being 8W I still think it will end up being 7W as then they can use the Barrel for NSA. Basically NMA will come first but it will be a big wing/wingbox version of NSA. It just makes too much sense. Especially if you only need 5,000NM range - which we are almost there with current Single Aisle's. You don't need to go 8W and LD2's - it will make it way too heavy and you'll never be able to use it for NSA.

Keesje - I've asked before - why wouldn't NMA be an 7W Ovoid big wing version of the NSA - much along the lines of your A322/A323 Studies - weight should be very comparable given that it would be shorter than A322/A323 for the same seating with a 36" wider LD3-45 in the belly for lots of cargo capacity?

How many times have we read that the Skin thickness of a carbon barrel in Single Aisle size is thicker than it structurally needs to be account to account for impact loads - couldn't that extra strength and creative shaping/bracing with the Fuselage frames in the Crown and cargo areas (which wouldn't weigh that much in Carbon) offset the disadvantages of the pressurizing issues of an oval?

Have we not also seen rumours from Boeing sources that they are not actually thinking about a pure Oval? Basically it would be too different circular cross sections joined at the floor beam? The top being sized for the 7W Cabin, with the bottom being a smaller portion of a much larger circle - with the same width as the Cabin but shallower depth. I am not a structural engineer but I would have to guess this would be a lot simpler from a structure standpoint.

Double bubbles have been around for ages, 737, 767, 747 to name a few. For CFRP fuselages. I'm not sure if it would be as effective. Bending moments around the floor seem hard to avoid for a layered carbon skin.

c933103, Varying cross section height is very pratical because of double bubble floor loading, turning it 90 degree would require a vertical load carrying wall in the cabin. Technically possible, but apparently not practical (Airbus P500 concept) http://3.bp.blogspot.com/_-Oqf_vOmanM/SpEWrtulsUI/AAAAAAAAAHU/4PdN0sFL5Tw/s1600/Airbus_P500_concept.JPG

Personally I wouldn't be really surprised if Boeing stays away from CFRP fuselage for this aircraft. Production infrastructure / upfront investment, simplicity of outsourcing, repair and overhaul, questionable weight savings. it has to make sense.What if Al Li pulls forward positive ROI by 6 years?

If NMA could be bigger NSA or the other way around seems sematics if they are initiated at the same time.

How is this relatated to Airbus shelving the A320plus?

Is the decision on cross section for the NMA so important that Airbus Decided to shelve the A321plus?

Airbus has a good idea of what the NMA will be: 220-270 seats in a 2 class configuration with a max range up to 5000nm. Given that information they decided to focus on production instead of development

RJMAZ wrote:

morrisond wrote:

Keesje - I've asked before - why wouldn't NMA be an 7W Ovoid big wing version of the NSA - much along the lines of your A322/A323 Studies

Boeing could do that. But then Airbus responds with an identical plane scaled up 10% to allow 8abreast. We then have a repeat of the 767 Vs A330 where Airbus would again outsell Boeing 2 to 1.

No one's crazy enough to go 7ab again. You could just go 8ab and a shorter fuselage using the same technology.

morrisond wrote:

Have we not also seen rumours from Boeing sources that they are not actually thinking about a pure Oval? Basically it would be too different circular cross sections joined at the floor beam?

I came up with that idea and made the graphics for that in Photoshop. They weren't runours from Boeing I made them up out of thin air.

RJMAZ - so your saying you believe that Boeing will do two different cross sections for NMA and NSA? If they are going to do 8W and LD2's why not just use 787 Barrels.

They will do 7W for weight - and it's not that crazy if you don't oversize it for LD2's which you don't need for NSA. A Hybrid Double Circular Fuselage is not that much of a penalty in Surface or wetted area as one would believe. There is not that large a penalty for that extra Aisle, when you start looking at Non -Circular cross sections - especially when you look at the premium Cabin where you could probably squeeaze in 1x1x1 pods and 2x2x2 Business class with about 20" wide seats.

Yes - you drew that Diagram - however as I pointed out in previous threads - you are Misrepresenting the actual width of an LD3-45 - and you did not come up with the idea of using two different circular cross sections. That came from many news article from last year. https://www.investors.com/news/more-det ... -fuselage/

Nice drawing though.

Newbiepilot wrote:

How is this relatated to Airbus shelving the A320plus?

Is the decision on cross section for the NMA so important that Airbus Decided to shelve the A321plus?

Airbus has a good idea of what the NMA will be: 220-270 seats in a 2 class configuration with a max range up to 5000nm. Given that information they decided to focus on production instead of development

Why are you always - without exception - attacking keesje's posts? First of all, he's not the only one talking about Boeing aircraft in an Airbus thread. And second, it is very much related to the topic of this thread. We're all speculating why Airbus made this decision, and it could very much have something to do with Boeing's plans.

7 abreast has no sense from Airline POW, it's either 6 or 8. from pax POW 7 or 5 are very good... but the economy always wins over comfort (unless you have a thick wallet and want to fly in biz or Y+). Still airlines have to save money to fence attacks against ULCC.

Quite right - If Boeing does an 7W NMA (NSA XL) and NSA reusing a lot of the same parts as NMA (Tail, Barrels, Systems, Possibly tail) - I don't think an A320 Based A322/323 will cut it.

Just the extra premium revenue Boeing will get from the 2x will give it a significant advantage and help it fight off COMAC in the future when they get going. I think Airbus will have to match Boeing and do a 7W barrel - which kind of makes sense as they will have C-Series 5W, 7W New Airplane and 9W A350 Derivatives - that's a nice line-up and would give them many options for derivatives in the future.

Kikko19 wrote:

7 abreast has no sense from Airline POW, it's either 6 or 8. from pax POW 7 or 5 are very good... but the economy always wins over comfort (unless you have a thick wallet and want to fly in biz or Y+). Still airlines have to save money to fence attacks against ULCC.

If you are not doing Circular cross sections - 7W is not that much of a penalty - it's maybe 20% more cross section for 16.7% more Economy seats, and potentially 50% more Business (2x2x2) and 50% more pods (1x1x1).

Without going and digging out all the Calcs again that difference (3-4% in cross section) is about the difference between A320 and 737 and it doesn't seem to hurt the A320 that much. We are talking about microscopic differences in operating costs. Engines and Wings are a lot more important.

JetBuddy wrote:

Newbiepilot wrote:

How is this relatated to Airbus shelving the A320plus?

Is the decision on cross section for the NMA so important that Airbus Decided to shelve the A321plus?

Airbus has a good idea of what the NMA will be: 220-270 seats in a 2 class configuration with a max range up to 5000nm. Given that information they decided to focus on production instead of development

Why are you always - without exception - attacking keesje's posts? First of all, he's not the only one talking about Boeing aircraft in an Airbus thread. And second, it is very much related to the topic of this thread. We're all speculating why Airbus made this decision, and it could very much have something to do with Boeing's plans.

I didnt realize asking a question is an attack. It is a legitimate question. How is all of this cross section discussion about Boeing's design related to Airbus' decision.

morrisond wrote:

If you are not doing Circular cross sections - 7W is not that much of a penalty

We're not talking an oval 7ab against a circular 8ab. We're talking oval Vs oval, same fuselage, engine and wing tech.

The 8ab oval will beat the 7ab oval. You could just run the 8ab fuselage slightly shorter if you insisted on having an equal number of seats.

The extra taper of the 8ab due to its lower fineness ratio means there is slightly more wasted space in the tail. This is completely offset by the aisle area efficiency of 8ab. Less aisle area wasted.

7ab would be extremely vulnerable against an 8ab response.

morrisond wrote:

RJMAZ - so your saying you believe that Boeing will do two different cross sections for NMA and NSA? If they are going to do 8W and LD2's why not just use 787 Barrels.

I'm expecting a 787 barrel. Nearly everyone's seen my 787 lightweight posts.

An 8ab circular fuselage with LD2's would probably be the perfect size for this segment. Basically 6inchs widers than a 767 to allow 8ab with 17.5inch seats. It would be relatively short but not as stubby as an A310. It would be simple, good aisle to seat ratio and allow cargo though with a low max takeoff weight you'd have to sacrifice range for payload.

But as Boeing already has a 9ab composite aircraft it would be much cheaper to use that. It wouldn't be ideal from a weight perspective, it might be a little big capacity wise and it might be a little stubby. But if it shared say 50% commonality with the 787-8 that would help reduce production costs of other models.

But we might know in a few months.

8ab oval would be the best most expensive option. I would be impressed if Boeing had the balls to invest that much money.

airmagnac wrote:

Revelation wrote:

It also makes me wonder what role the 4th XFW line plays in all of this. Was it less helpful than planned therefore a lot of rework is needed? Was it more helpful than planned therefore the manpower will be spent on rolling it out over all the lines? Did it enable a lot of more optimizations and more manpower is needed? Ahh, so many questions...

As mentioned before, to increase production rates or improve production in general, you have multiple options which are not exclusive :
1) duplicate assembly stations (such as add a new FAL, or a new sub-station within a FAL)
2) improve assembly processes within an assembly line or a sub-station, by playing with e.g. tooling or sequencing of part installation
3) improve supply chain information flows over the whole value stream from finished product back up to elementary parts (aka 'Lean'). This also includes communication with manuf engineering & design engineering to solve day-to-day issues ("oops I dropped a hammer on the fuselage structure...do we have to throw it all away, or can we push forward ?")
4) change the design of the aircraft to ease the production tasks (for example by making more room within an assembly for assembly personnel to get in and install a part)

Your linked article is an illustration of 1)
The "focus on production" that started this thread is likely going to be a combination of 3) and 4)

And no need to conjure up wild speculation based on the new line, as it is hardly entering service. So its capabilities and impacts cannot be known, much less acted upon...

Thanks again for another interesting reply.

When I read the ST article it seemed pretty clear to me that the work being done for the new line at XFW would be both (1) and (2).

And the article is from over two years ago but had no info on when the new line would be starting production, so thanks for the update.

It's interesting that Airbus would decide to re-prioritize A320+/++ in favor of production while not knowing the capabilities and impacts of this new production line technology they've invested in.

I'm sorry if my speculations seem wild but there is not much coverage of this topic in the media, yet I think we're seeing it's more impactful than a casual observer might think.

Revelation wrote:

the work being done for the new line at XFW would be both (1) and (2).

You're actually correct, it is 1 and 2. That somehow got lost in my train of thought

Revelation wrote:

production while not knowing the capabilities and impacts of this new production line technology they've invested in.

And yet how would that be any different from starting work on a MoM/797 without knowing the full capabilities of the current development (777X) ?

In reality, while I'm not in manuf engineering, I'm pretty sure they have simulated the new line and tested each part of it. So they would have a pretty good idea of what to expect.

Revelation wrote:

I think we're seeing it's more impactful than a casual observer might think.

Just my own opinion, but I think it's the observable part of a huge change in the industry. From driven by super-duper latest-tech- for flight ops, I believe we are headed to an optimisation of the complete lifecycle including production, maintenance etc...
All the discussions around here regarding MoM are still implicitly assuming that an all-new aircraft can bring to the table significant benefits in direct operating (flight) costs which cannot be matched by upgrading existing designs. Yet I believe that is not true ; most gains in the past 30 years are almost exclusively due to engine SFC, and engines can be upgraded, see NEO/MAX.
If aerospace tech cannot bring anything to the table, then poems need to look elsewhere. And that does not necessarily require an all-new design either.
This is what both A and B are going after on current programs. And This is the fundamental vulnerability of the MoM, and why Boeing has to take it's time with the business case.

One element of the NMA sketch I haven’t seen much commentary on is that the actual Boeing one seems to show a 767 style cockpit (also 777/757), rather than the 787, and a max tailcone.

Do these elements imply it would actually be an aluminum frame?

texl1649 wrote:

One element of the NMA sketch I haven’t seen much commentary on is that the actual Boeing one seems to show a 767 style cockpit (also 777/757), rather than the 787, and a max tailcone.

Do these elements imply it would actually be an aluminum frame?

I am told it’s for sure to be a composite plane built along the lines of the 787 from people that should know.

Can you join aluminium and carbon composite?I imagine you can as there are aircraft with carbon fibre wings and metal bodies.I ask with reference to the above posts.
I believe that the 777 nose is a 767 nose grafted on.If so it will have just had a total upgrade for the 777x series.If they are looking to minimise development time and cost ( and increase commonality) then it would be a smart trick to do this if possible for the 797.
MLG .whilst on the commonality subject,could they use the 767 MLG as well? Just pondering.Again would save time and money.the 762 would be about right -no?

parapente wrote:

Can you join aluminium and carbon composite?I imagine you can as there are aircraft with carbon fibre wings and metal bodies.I ask with reference to the above posts.
I believe that the 777 nose is a 767 nose grafted on.If so it will have just had a total upgrade for the 777x series.If they are looking to minimise development time and cost ( and increase commonality) then it would be a smart trick to do this if possible for the 797.
MLG .whilst on the commonality subject,could they use the 767 MLG as well? Just pondering.Again would save time and money.the 762 would be about right -no?

I think it’s just a placeholder drawing and people are reading too much into it.

Wasn't really referring to the drawing ,just the concept/idea.If they have already reused the cockpit section for the 777 and that has just been updated for the 777x then it might make sense to use it for this a/c which will be a twinaisle too.Fantastic commonality and lower costs.

parapente wrote:

Can you join aluminium and carbon composite?I imagine you can as there are aircraft with carbon fibre wings and metal bodies.I ask with reference to the above posts.

You can but you need to be very careful about different stiffness ratios, thermal expansion ratios and other issues like galvanic corrosion etc. at the interfaces.