Or Boeings new aircraft will not be out before the 2030s when the Ultrafan is mature (350neo) and scalable to smaller designs.

The scalable comments go back a ways, at least to early last year:
https://www.rolls-royce.com/media/press ... lades.aspx

I take that as very general. If they make a ~40,000 lb thrust engine, I'm sure it will be its own design, sharing little directly with the demonstrator, but sharing general features like a geared fan, composite blades, CMC hot section parts, and a very high pressure ratio.

Interesting. I would have to guess as the odds of NMA arriving by 2025 are basically zero now - a timeline later in decade might work for Rolls and why the discussion is revived.

Put this under interesting in terms of another data point that makes 2-3-2 more likely.

Plus it occurred to me during the 350F discussion that a normal base size pallet of 96"x125" could fit nicely in an 2-3-2 cargo hold lengthwise that is about 30" wider than an A320.

An LD3-45's base is 61.5" so you only need 34.5" more to fit a 96"x125" pallet. Given the belly would be flatter on a cross section that is 30" wider at 186" than an A320 - it should just about fit. Maybe not much higher than an LD3-45 at 48" or so - but that should still allow you to cross ship it.

Perfect opportunity for Airbus to launch a re-winged A322 using slightly uprated versions of the GTF and LEAP-X...

744SPX wrote:

Perfect opportunity for Airbus to launch a re-winged A322 using slightly uprated versions of the GTF and LEAP-X...

Until Boeing actually launches NMA, I don't see the need to. They would just be spending money developing a plane to secure sales they already would have had with the A321.

The only relevant quote is:

“It is fairly well documented that Boeing is exploring the opportunity for a new aircraft,” Rolls Chief Executive Officer Warren East said at its annual meeting on Thursday. “Like the other engine manufacturers, I am sure, we are in dialog with Boeing about that.”

To be honest there is nothing to take away from it. Obviously the 2025 EiS of 2019 has sailed, so the timetable will look different.

Stitch wrote:

744SPX wrote:

Perfect opportunity for Airbus to launch a re-winged A322 using slightly uprated versions of the GTF and LEAP-X...

Until Boeing actually launches NMA, I don't see the need to. They would just be spending money developing a plane to secure sales they already would have had with the A321.

They would get an premium/higher margin over the A321 and have first mover advantage in an segment where there is no competition yet. On the other hand it would force Boeing to reconsider/cancel the NMA as an big part of the market will be lost.

I do think in the long term it is better for Airbus to let Boeing grab 40-60% with the NMA and just grab the remainder of the market with the A322. In an duopoly usually you don't want to kill your competition, you just want to do a bit better yourself...

JonesNL wrote:

They would get an premium/higher margin over the A321 and have first mover advantage in an segment where there is no competition yet. On the other hand it would force Boeing to reconsider/cancel the NMA as an big part of the market will be lost.

I do think in the long term it is better for Airbus to let Boeing grab 40-60% with the NMA and just grab the remainder of the market with the A322. In an duopoly usually you don't want to kill your competition, you just want to do a bit better yourself...

First mover advantage didn't win the day for the de Havilland Comet.

Boeing's market calculations will have to include any possible Airbus move.

787 had to be launched knowing Airbus could do something like A350.

Boeing has to be confident the market can support its product and an Airbus response and Comac too.

If it can't stand that challenge it won't be launched, and maybe that's why it hasn't been launched, although we have learned it was on track for launching when the 2nd MCAS crash happened.

JonesNL wrote:

They would get an premium/higher margin over the A321 and have first mover advantage in an segment where there is no competition yet.

But that is kind of the point - there is no competition for Airbus in that market segment right now. The A321 might not be the best option (hence Boeing studying NMA), but right now it is the only option. They're going to buy the A321 because they can make it work, or they're just not going to buy, period. I mean it's not like they are going to go to Boeing and order a 767-300ER.

JonesNL wrote:

On the other hand it would force Boeing to reconsider/cancel the NMA as an big part of the market will be lost.

To listen to some of the pundits on this forum, there is no real market to lose as it doesn't exist.

But then maybe that is Boeing's plan - "trick" Airbus into investing billions in an A322 with no real market just as some believe they "tricked" Airbus to invest in the A380 by floating all those phantom 747 re-hashes in the 1990s.

Stitch wrote:

JonesNL wrote:

They would get an premium/higher margin over the A321 and have first mover advantage in an segment where there is no competition yet.

But that is kind of the point - there is no competition for Airbus in that market segment right now. The A321 might not be the best option (hence Boeing studying NMA), but right now it is the only option. They're going to buy the A321 because they can make it work, or they're just not going to buy, period. I mean it's not like they are going to go to Boeing and order a 767-300ER.

JonesNL wrote:

On the other hand it would force Boeing to reconsider/cancel the NMA as an big part of the market will be lost.

To listen to some of the pundits on this forum, there is no real market to lose as it doesn't exist.

But then maybe that is Boeing's plan - "trick" Airbus into investing billions in an A322 with no real market just as some believe they "tricked" Airbus to invest in the A380 by floating all those phantom 747 re-hashes in the 1990s.

That would be a risky trick though. A322 would sit on a niche market. BUT, it is a niche market with low investment rate and 0 competition.
Boing doesn't have any answers for that. They would shoot themselves in their foot by spending at least 20 billion dollars for a niche market filled by their competitors.

ewt340 wrote:

Stitch wrote:

JonesNL wrote:

They would get an premium/higher margin over the A321 and have first mover advantage in an segment where there is no competition yet.

But that is kind of the point - there is no competition for Airbus in that market segment right now. The A321 might not be the best option (hence Boeing studying NMA), but right now it is the only option. They're going to buy the A321 because they can make it work, or they're just not going to buy, period. I mean it's not like they are going to go to Boeing and order a 767-300ER.

JonesNL wrote:

On the other hand it would force Boeing to reconsider/cancel the NMA as an big part of the market will be lost.

To listen to some of the pundits on this forum, there is no real market to lose as it doesn't exist.

But then maybe that is Boeing's plan - "trick" Airbus into investing billions in an A322 with no real market just as some believe they "tricked" Airbus to invest in the A380 by floating all those phantom 747 re-hashes in the 1990s.

That would be a risky trick though. A322 would sit on a niche market. BUT, it is a niche market with low investment rate and 0 competition.
Boing doesn't have any answers for that. They would shoot themselves in their foot by spending at least 20 billion dollars for a niche market filled by their competitors.

Yes - assuming they only ever used that cross section for that one product - which they would never do. With the the choice of the right cross section it could function as an NSA replacement as well the 767 market segment up to capacities such as A330-200.

That is where they could get enormous economies of scale and it might be up to $30B to do an NMA and NSA - but when you are spreading the cost over 5,000-10,000 frames - it's not so big a number ($3-6Million per frame in development).

Another reason why 7AB makes no sense for NMA.

Wouldn’t an A322 suffer from the same operational issues as a 757-300. How long exactly can you make a single aisle before it actually does not make sense. I’m genuinely just curious

Also it’s obvious to me that Boeing wants to use NMA to answer two markers at once. Which seems evident by their constant focus on the airframe rather than the engines and calhouns belief that they have the advantage with composite materials. Both the MOM and also the 321 competitor. They’ll use the MAX10 to satisfy their customers that cannot wait.

744SPX wrote:

Another reason why 7AB makes no sense for NMA.

We should talk about that someday. Maybe someone could come up with a spreadsheet or two that might tells us if it's a good idea or not.

Opus99 wrote:

Wouldn’t an A322 suffer from the same operational issues as a 757-300. How long exactly can you make a single aisle before it actually does not make sense. I’m genuinely just curious

Probably not. It doesn't seems like they would stretch A322 over 50m. Currently A321 is around 44.51m. The next stretch would probably be around 4.3m stretch (around 8 frames stretch / 168 inch stretch).

Capacity wise, it would be closer to B757-200 than B757-300.

Revelation wrote:

744SPX wrote:

Another reason why 7AB makes no sense for NMA.

We should talk about that someday. Maybe someone could come up with a spreadsheet or two that might tells us if it's a good idea or not.

I see what you just did there...

ewt340 wrote:

Opus99 wrote:

Wouldn’t an A322 suffer from the same operational issues as a 757-300. How long exactly can you make a single aisle before it actually does not make sense. I’m genuinely just curious

Probably not. It doesn't seems like they would stretch A322 over 50m. Currently A321 is around 44.51m. The next stretch would probably be around 4.3m stretch (around 8 frames stretch / 168 inch stretch).

Capacity wise, it would be closer to B757-200 than B757-300.

Ah i see. Thanks

I wonder what they are pitching to Boe and what Boe has RFP
https://www.flightglobal.com/engines/ro ... 52.article

TropicalSky wrote:

I wonder what they are pitching to Boe and what Boe has RFP
https://www.flightglobal.com/engines/ro ... 52.article

Kinda interesting, suggests a CFM LEAP follow-on may be advantaged since we know it can scale down to MAX7/A319 sized applications too.

Even though Rolls-Royce has always said that the geared UltraFan architecture is scalable and could be developed be applied for a range of future aircraft, East acknowledges that the design lends itself primarily to widebodies. “Below widebody long-distance travel… we totally understand that UltraFan isn’t necessarily the right power and propulsion answer in those applications.”

Opus99 wrote:

ewt340 wrote:

Opus99 wrote:

Wouldn’t an A322 suffer from the same operational issues as a 757-300. How long exactly can you make a single aisle before it actually does not make sense. I’m genuinely just curious

Probably not. It doesn't seems like they would stretch A322 over 50m. Currently A321 is around 44.51m. The next stretch would probably be around 4.3m stretch (around 8 frames stretch / 168 inch stretch).

Capacity wise, it would be closer to B757-200 than B757-300.

Ah i see. Thanks

Apart from that, the A320 has a considerable bigger cross section than the 757. Which makes all the difference for comfort, cargo options and structural efficiency.

744SPX wrote:
Another reason why 7AB makes no sense for NMA.

We should talk about that someday. Maybe someone could come up with a spreadsheet or two that might tells us if it's a good idea or not.

In all spreadsheets I've made over the years, at the same technology (materials, engines), same spec (capacity, range) a single aisle seems to come out significatly lighter (10-15%).

If the requirement is for real high capacity, a conventional single aisle (20 inch) would become impracticle. But a dual aisle might be uncompetitive 200-250 seats, up to 2-3 hours, a huge part of the pie.

Very cool to see engine manufacturers being so active. This is what triggers programs and progress on the manufacturer's sides.

Noshow wrote:

Very cool to see engine manufacturers being so active. This is what triggers programs and progress on the manufacturer's sides.

I would hope that a sound business plan aiming for an existing and exploitable market niche would trigger programs and progress. Engine efficiency is a considerable but not all-deciding implication to that end.

It all breaks down to the cost and efficiency advantage some new generation can offer. This is why better engines always will be needed first. Engines take longer to develop than aircraft so it has to start at engine manufacturers.
I agree there has to be a market segment, a good product at the right price, being available in time when airlines need it and such.

CRJockey wrote:

Noshow wrote:

Very cool to see engine manufacturers being so active. This is what triggers programs and progress on the manufacturer's sides.

I would hope that a sound business plan aiming for an existing and exploitable market niche would trigger programs and progress. Engine efficiency is a considerable but not all-deciding implication to that end.

You would hope, but in the real world A320neo happened because Airbus felt threatened by BBD C Series, and 737 MAX happened because Boeing literally was threatened to lose AA as a customer if it did not come up with a response.

keesje wrote:

Opus99 wrote:

ewt340 wrote:

Probably not. It doesn't seems like they would stretch A322 over 50m. Currently A321 is around 44.51m. The next stretch would probably be around 4.3m stretch (around 8 frames stretch / 168 inch stretch).

Capacity wise, it would be closer to B757-200 than B757-300.

Ah i see. Thanks

Apart from that, the A320 has a considerable bigger cross section than the 757. Which makes all the difference for comfort, cargo options and structural efficiency.

744SPX wrote:
Another reason why 7AB makes no sense for NMA.

We should talk about that someday. Maybe someone could come up with a spreadsheet or two that might tells us if it's a good idea or not.

In all spreadsheets I've made over the years, at the same technology (materials, engines), same spec (capacity, range) a single aisle seems to come out significatly lighter (10-15%).

If the requirement is for real high capacity, a conventional single aisle (20 inch) would become impracticle. But a dual aisle might be uncompetitive 200-250 seats, up to 2-3 hours, a huge part of the pie.

Luckily Boeing and Airbus have evolved beyond spreadsheets.

Revelation wrote:

CRJockey wrote:

Noshow wrote:

Very cool to see engine manufacturers being so active. This is what triggers programs and progress on the manufacturer's sides.

I would hope that a sound business plan aiming for an existing and exploitable market niche would trigger programs and progress. Engine efficiency is a considerable but not all-deciding implication to that end.

You would hope, but in the real world A320neo happened because Airbus felt threatened by BBD C Series, and 737 MAX happened because Boeing literally was threatened to lose AA as a customer if it did not come up with a response.

How is this a "but"? In the "real world" Bombardier tried to exploit a market niche with a new product. Airbus and Boeing needed to protect their (ongoing exploitation of that very same) market niche and had the benefit of existing, more or less update-ready platforms.

morrisond wrote:

keesje wrote:

Opus99 wrote:

Ah i see. Thanks

Apart from that, the A320 has a considerable bigger cross section than the 757. Which makes all the difference for comfort, cargo options and structural efficiency.

744SPX wrote:
Another reason why 7AB makes no sense for NMA.

We should talk about that someday. Maybe someone could come up with a spreadsheet or two that might tells us if it's a good idea or not.

In all spreadsheets I've made over the years, at the same technology (materials, engines), same spec (capacity, range) a single aisle seems to come out significatly lighter (10-15%).

If the requirement is for real high capacity, a conventional single aisle (20 inch) would become impracticle. But a dual aisle might be uncompetitive 200-250 seats, up to 2-3 hours, a huge part of the pie.

Luckily Boeing and Airbus have evolved beyond spreadsheets.

They have, but the fundamental advantage of the narrow body remains and can still be reasonably estimated by spreadsheet.

The issue is that there is no one cross sectional configuration that is efficient enough at the low capacity end of the MOM and of a practical enough length at the high capacity end. The advantages of 7abreast compared to a 6 abreast (single aisle) are not realised until a capacity level whereby 8abreast is a better option than both anyway.

More power to Boeing if they can pull it off but they’ll need something more magic than carbon and electric to make it a reality and have to have the magic sauce so well protected so as not to have a next gen narrow body use the same tech, maintain the fundamental advantage and wipe the floor with it.

Fred


Sent from my iPad using Tapatalk

flipdewaf wrote:

morrisond wrote:

keesje wrote:

Apart from that, the A320 has a considerable bigger cross section than the 757. Which makes all the difference for comfort, cargo options and structural efficiency.



In all spreadsheets I've made over the years, at the same technology (materials, engines), same spec (capacity, range) a single aisle seems to come out significatly lighter (10-15%).

If the requirement is for real high capacity, a conventional single aisle (20 inch) would become impracticle. But a dual aisle might be uncompetitive 200-250 seats, up to 2-3 hours, a huge part of the pie.

Luckily Boeing and Airbus have evolved beyond spreadsheets.

They have, but the fundamental advantage of the narrow body remains and can still be reasonably estimated by spreadsheet.

The issue is that there is no one cross sectional configuration that is efficient enough at the low capacity end of the MOM and of a practical enough length at the high capacity end. The advantages of 7abreast compared to a 6 abreast (single aisle) are not realised until a capacity level whereby 8abreast is a better option than both anyway.

More power to Boeing if they can pull it off but they’ll need something more magic than carbon and electric to make it a reality and have to have the magic sauce so well protected so as not to have a next gen narrow body use the same tech, maintain the fundamental advantage and wipe the floor with it.

Fred


Sent from my iPad using Tapatalk

In your opinion.

We will see what happens.

In my opinion I'm comfortable enough with the numbers that if there is a disadvantage to 7W it's small enough to not offset the Industrial and scale benefits of being able to use a Future NSA cross section as the basis for the NMA-5 and later on larger models with bigger wings/engines/gear/tail.

That is where the concept of 7W is very attractive. Otherwise you are probably stuck with two different cross sections to cover the space which will be a lot more expensive.

If the last few % of efficiency was the determining factor of who dominates the sales race the MAX 8 would have outsold the A320 NEO 10:1 and the MAX9/10 would be doing a lot better against the A321 as not many Airlines need the extra capabilities.

morrisond wrote:

flipdewaf wrote:

morrisond wrote:

Luckily Boeing and Airbus have evolved beyond spreadsheets.

They have, but the fundamental advantage of the narrow body remains and can still be reasonably estimated by spreadsheet.

The issue is that there is no one cross sectional configuration that is efficient enough at the low capacity end of the MOM and of a practical enough length at the high capacity end. The advantages of 7abreast compared to a 6 abreast (single aisle) are not realised until a capacity level whereby 8abreast is a better option than both anyway.

More power to Boeing if they can pull it off but they’ll need something more magic than carbon and electric to make it a reality and have to have the magic sauce so well protected so as not to have a next gen narrow body use the same tech, maintain the fundamental advantage and wipe the floor with it.

Fred


Sent from my iPad using Tapatalk

In your opinion.

based on well founded engineering models that correlate with both fundamental physical expectations and historic designs. I.e. both theoretical and empirical evidence.

morrisond wrote:

We will see what happens.

In my opinion I'm comfortable enough with the numbers that if there is a disadvantage to 7W it's small enough to not offset the Industrial and scale benefits of being able to use a Future NSA cross section as the basis for the NMA-5 and later on larger models with bigger wings/engines/gear/tail.

Someone can be comfortable that there’s a beardy weirdy in the sky controlling the earth, doesn’t make it true.

morrisond wrote:

That is where the concept of 7W is very attractive. Otherwise you are probably stuck with two different cross sections to cover the space which will be a lot more expensive.

Or accept that a fully fungible market doesn’t need a full capacity coverage, a gap in a market is an acceptable phenomenon.

morrisond wrote:

If the last few % of efficiency was the determining factor of who dominates the sales race the MAX 8 would have outsold the A320 NEO 10:1

I wasn’t aware that the MAX had a 10% performance advantage over the A320?

morrisond wrote:

and the MAX9/10 would be doing a lot better against the A321 as not many Airlines need the extra capabilities.

or the few% does matter and the A321NEO is actually better? Or the extra capability comes a low/no cost?

Fred


Sent from my iPad using Tapatalk

morrisond wrote:

flipdewaf wrote:

morrisond wrote:

Luckily Boeing and Airbus have evolved beyond spreadsheets.

They have, but the fundamental advantage of the narrow body remains and can still be reasonably estimated by spreadsheet.

The issue is that there is no one cross sectional configuration that is efficient enough at the low capacity end of the MOM and of a practical enough length at the high capacity end. The advantages of 7abreast compared to a 6 abreast (single aisle) are not realised until a capacity level whereby 8abreast is a better option than both anyway.

More power to Boeing if they can pull it off but they’ll need something more magic than carbon and electric to make it a reality and have to have the magic sauce so well protected so as not to have a next gen narrow body use the same tech, maintain the fundamental advantage and wipe the floor with it.

Fred


Sent from my iPad using Tapatalk

In your opinion.

We will see what happens.

In my opinion I'm comfortable enough with the numbers that if there is a disadvantage to 7W it's small enough to not offset the Industrial and scale benefits of being able to use a Future NSA cross section as the basis for the NMA-5 and later on larger models with bigger wings/engines/gear/tail.

That is where the concept of 7W is very attractive. Otherwise you are probably stuck with two different cross sections to cover the space which will be a lot more expensive.

If the last few % of efficiency was the determining factor of who dominates the sales race the MAX 8 would have outsold the A320 NEO 10:1 and the MAX9/10 would be doing a lot better against the A321 as not many Airlines need the extra capabilities.

It's not an opinion that 6-abrest & 8-abreast are better than 7-abreast. Single aisle advantages and the extra row + LD3 container that came with 8-abreast configuration is the proof for it.

ewt340 wrote:

morrisond wrote:

flipdewaf wrote:

They have, but the fundamental advantage of the narrow body remains and can still be reasonably estimated by spreadsheet.

The issue is that there is no one cross sectional configuration that is efficient enough at the low capacity end of the MOM and of a practical enough length at the high capacity end. The advantages of 7abreast compared to a 6 abreast (single aisle) are not realised until a capacity level whereby 8abreast is a better option than both anyway.

More power to Boeing if they can pull it off but they’ll need something more magic than carbon and electric to make it a reality and have to have the magic sauce so well protected so as not to have a next gen narrow body use the same tech, maintain the fundamental advantage and wipe the floor with it.

Fred


Sent from my iPad using Tapatalk

In your opinion.

We will see what happens.

In my opinion I'm comfortable enough with the numbers that if there is a disadvantage to 7W it's small enough to not offset the Industrial and scale benefits of being able to use a Future NSA cross section as the basis for the NMA-5 and later on larger models with bigger wings/engines/gear/tail.

That is where the concept of 7W is very attractive. Otherwise you are probably stuck with two different cross sections to cover the space which will be a lot more expensive.

If the last few % of efficiency was the determining factor of who dominates the sales race the MAX 8 would have outsold the A320 NEO 10:1 and the MAX9/10 would be doing a lot better against the A321 as not many Airlines need the extra capabilities.

It's not an opinion that 6-abrest & 8-abreast are better than 7-abreast. Single aisle advantages and the extra row + LD3 container that came with 8-abreast configuration is the proof for it.

Good luck in trying to get a 330 cross section to compete in the NSA space.

For approximately the same skin area a tight light 7W has more internal volume than a 6W of similar capacity. Two tight aisles of 777X width are approximately equal in floor space to one Single aisle of 27" when you adjust the cabin for the same number of passengers. There is not as big a disadvantage to 7W as some make it out to be.

Boeing could launch two complete clean sheets based on two different cross sections in the next 5 years to replace MAX and 757/767 - but somehow I think the odds of that are very low.

They will pick either 7W or 6W. I have faith that Boeing and Airbus engineers using modern Supercomputers if they choose too could come up with a very efficient 7W. Some of the properties that make Carbon possibly not the best choice for a single aisle (skins that need to be thicker than optimal to deal with ramp rash - but still lighter than metal) - can be put to good use in making something like a 7W Double Circle cross section work.

Carbon can also be used to make much larger more complex monolithic parts for instance by making the floor beams, lower lobe all one big part that also provides the structure of the cargo compartment to help deal with the abnormal stresses. Then tie the floor/ sides and ceiling together with the lining of the cargo compartment attached to that big monolithic part to effectively build one very large keel beam.

Boeing has been playing with 7W for at least 15 years. If they want to do it they will figure out a way to make the tradeoffs acceptable. I'm sure Airbus could do the same thing and with the C220 in the family - it could actually be a great cross section for them to replace A320/330 (with different wings/gear/ engines) and stretch C220 up into MAX8 A320 space so they don't have to cover that.

Boeing has been playing with 7W for at least 15 years.

At least 20 years. The fact no airline, engine OE or stakeholder committed to, no doubt endless discussions, presentations and proposals for all those years, should have been a signal 7 might not be brilliant. http://www.patentbuddy.com/Patent/6616100

Opus99 wrote:

Wouldn’t an A322 suffer from the same operational issues as a 757-300. How long exactly can you make a single aisle before it actually does not make sense. I’m genuinely just curious

I seem to recall Boeing marketing the 757-200 in the 1980s as the longest narrow body airplane that can be built/operated efficiently. Or something similar.

keesje wrote:

Boeing has been playing with 7W for at least 15 years.

At least 20 years. The fact no airline, engine OE or stakeholder committed to, no doubt endless discussions, presentations and proposals for all those years, should have been a signal 7 might not be brilliant. http://www.patentbuddy.com/Patent/6616100

Yes - as you know it was the rumoured cross section for NSA which was shelved when they decided to do the MAX and the MAX crashes sidelined the launch of 7W as the possible cross section the second time.

Have you seen Boeing launch a new 6W or 8W cross section in that time either?

SteelChair wrote:

Opus99 wrote:

Wouldn’t an A322 suffer from the same operational issues as a 757-300. How long exactly can you make a single aisle before it actually does not make sense. I’m genuinely just curious

I seem to recall Boeing marketing the 757-200 in the 1980s as the longest narrow body airplane that can be built/operated efficiently. Or something similar.

Well they then did go and build the -300 but then they didn't exactly fly off the shelves.

That being said passenger growth numbers will probably be a lot kinder to a 7W but the time of its EIS by say 2029-2030 and the bulk of the time when it is in full production from 2030-2050.

Slot restrictions and environmental concerns will cause the size of the optimal shorter range plane to grow. I can see an NSA not needing to carry any less than 200Y passengers by the time it would eventually EIS sometime in the next decade.

morrisond wrote:

In your opinion.

We will see what happens.

In my opinion I'm comfortable enough with the numbers that if there is a disadvantage to 7W it's small enough to not offset the Industrial and scale benefits of being able to use a Future NSA cross section as the basis for the NMA-5 and later on larger models with bigger wings/engines/gear/tail.

That is where the concept of 7W is very attractive. Otherwise you are probably stuck with two different cross sections to cover the space which will be a lot more expensive.

If the last few % of efficiency was the determining factor of who dominates the sales race the MAX 8 would have outsold the A320 NEO 10:1 and the MAX9/10 would be doing a lot better against the A321 as not many Airlines need the extra capabilities.

You seem to be the only one going on about 7AB.

If Boeing made a shared 7AB cross section for NSA and NMA that could bankrupt them. The efficiency penalty compared to a competing Airbus 6AB and 8AB would destroy them.

RJMAZ wrote:

If Boeing made a shared 7AB cross section for NSA and NMA that could bankrupt them. The efficiency penalty compared to a competing Airbus 6AB and 8AB would destroy them.

I keep coming back to that myself. I see NSA and NMA both being a common 6AB fuselage. Different Wings, Wingboxes, Gear, Engines, Tails will determine the capabilities and capacities. They'll start with the larger but lower volume NMA to perfect the manufacturing of the new 6AB platform. MAX will be produced until the backlog is nearly exhausted and then is replaced by the NSA which is the smaller but higher volume member of the new 6AB platform. I just can't see doing 7..where you give Airbus the opportunity to cut all of that weight eliminating an aisle and a seat (6AB)........ or you give Airbus the opportunity to cut all of that casm by simply adding one more seat (8AB). I respect your opinion and research Morris, but like RJMAX, I just can't see them doing it... 35 pages into this thread and nothing about anything that Calhoun said convinces me they will make a case for a unique 7AB light small twin aisle plane to fill the MoM space.

FiscAutTecGarte wrote:

RJMAZ wrote:

If Boeing made a shared 7AB cross section for NSA and NMA that could bankrupt them. The efficiency penalty compared to a competing Airbus 6AB and 8AB would destroy them.

I keep coming back to that myself. I see NSA and NMA both being a common 6AB fuselage. Different Wings, Wingboxes, Gear, Engines, Tails will determine the capabilities and capacities. They'll start with the larger but lower volume NMA to perfect the manufacturing of the new 6AB platform. MAX will be produced until the backlog is nearly exhausted and then is replaced by the NSA which is the smaller but higher volume member of the new 6AB platform. I just can't see doing 7..where you give Airbus the opportunity to cut all of that weight eliminating an aisle and a seat (6AB)........ or you give Airbus the opportunity to cut all of that casm by simply adding one more seat (8AB). I respect your opinion and research Morris, but like RJMAX, I just can't see them doing it... 35 pages into this thread and nothing about anything that Calhoun said convinces me they will make a case for a unique 7AB light small twin aisle plane to fill the MoM space.

The range could bottom out around 200 pax. Which would put it a bit higher than the 737 Max 8. I could see an NMA work for that range. I don't see the same cross section and fusalage work for an lower range NSA. If you are doing an New tail, Engine and wing, you might as well optimize the fusalage for smaller capabilities as well...

morrisond wrote:

ewt340 wrote:

morrisond wrote:

In your opinion.

We will see what happens.

In my opinion I'm comfortable enough with the numbers that if there is a disadvantage to 7W it's small enough to not offset the Industrial and scale benefits of being able to use a Future NSA cross section as the basis for the NMA-5 and later on larger models with bigger wings/engines/gear/tail.

That is where the concept of 7W is very attractive. Otherwise you are probably stuck with two different cross sections to cover the space which will be a lot more expensive.

If the last few % of efficiency was the determining factor of who dominates the sales race the MAX 8 would have outsold the A320 NEO 10:1 and the MAX9/10 would be doing a lot better against the A321 as not many Airlines need the extra capabilities.

It's not an opinion that 6-abrest & 8-abreast are better than 7-abreast. Single aisle advantages and the extra row + LD3 container that came with 8-abreast configuration is the proof for it.

Good luck in trying to get a 330 cross section to compete in the NSA space.

I’m not sure who is trying to make the A330 the default cross section for an 8 abreast space. It is of course 36inches greater than the 7 abreast you proposed and yet just one more seat across yet the model you propose is just 30 inches greater in width than the A320 but yet somehow manages to get an extra seat AND and an aisle.

morrisond wrote:

For approximately the same skin area a tight light 7W has more internal volume than a 6W of similar capacity.

Is that for the liquidised pax?

morrisond wrote:

Two tight aisles of 777X width are approximately equal in floor space to one Single aisle of 27" when you adjust the cabin for the same number of passengers.

And......?

morrisond wrote:

There is not as big a disadvantage to 7W as some make it out to be.

There’s no advantage or disadvantage, the economics are what they are, no special pleasing required.

morrisond wrote:

Boeing could launch two complete clean sheets based on two different cross sections in the next 5 years to replace MAX and 757/767 - but somehow I think the odds of that are very low.

I agree, two new cross sections within 10 years would be a stretch, can they really leave the 737 that long?

morrisond wrote:

They will pick either 7W or 6W. I have faith that Boeing and Airbus engineers using modern Supercomputers if they choose too could come up with a very efficient 7W.

And a similarly increased efficiency 6w, with its inherent advantages of 7w still intact.

morrisond wrote:

Some of the properties that make Carbon possibly not the best choice for a single aisle (skins that need to be thicker than optimal to deal with ramp rash - but still lighter than metal) - can be put to good use in making something like a 7W Double Circle cross section work.

Except that’s not really true, we see no large scale weight savings due to CFRP use, we even see it not used in newer generation narrowbody fuselages at all...

morrisond wrote:

Carbon can also be used to make much larger more complex monolithic parts for instance by making the floor beams, lower lobe all one big part that also provides the structure of the cargo compartment to help deal with the abnormal stresses. Then tie the floor/ sides and ceiling together with the lining of the cargo compartment attached to that big monolithic part to effectively build one very large keel beam

For use solely by aircraft with 2 aisles?

morrisond wrote:

Boeing has been playing with 7W for at least 15 years. If they want to do it they will figure out a way to make the tradeoffs acceptable.

Or you could say that they have been doing it for 15 years (I’d be surprised if it was even that short of a length of time) and still haven’t made it work.

morrisond wrote:

I'm sure Airbus could do the same thing and with the C220 in the family - it could actually be a great cross section for them to replace A320/330 (with different wings/gear/ engines) and stretch C220 up into MAX8 A320 space so they don't have to cover that.

Yes, imagine the opportunities of being able to go more out of round without as much weight penalty does to the configurations of single aisles and head/shoulder space optimisation.

Special pleading.

Fred


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7 abreast is starting to feel like 4 engines: was good back in the day, but times have changed...

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Seems Boeing is re-engaging with engine suppliers regarding NMA. Including RR which pulled out previously as it could not meet Boeing's tight development schedule, which obviously no longer applies.

"According to Bloomberg, Rolls-Royce (RR) is in talks with Boeing regarding its new aircraft program, presumed to be the NMA (new midsize airplane) and anticipated to be designated the 797."

https://simpleflying.com/rolls-royce-bo ... lane-type/

To the contrary, 7ab is the solution for the future.

oschkosch wrote:

7 abreast is starting to feel like 4 engines: was good back in the day, but times have changed...

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I don’t think that’s how that works. The configuration that maximises efficiency in that particular frame is what works

Let's look at size of comparable capacity 6W and 7W cabins again.

Assume A320 cross section for 6W (ignoring putting an extra wide aisle in it) and an 168"x 184" Double circle cross section for a 7W.

Apparently the NMA-5 will target 321 and a potential 322. The 322 is supposedly A321 plus 3 rows which works out to 220 seats at 32" according to Airbus A321 ACAP.

That would put the length of an A322 at 46.93M. The passenger cabin would be about 37 rows looking at the ACAP for about 30M plus another 1 M for extra space in the exit rows. That puts the passenger cabin at 31M long. The width of the passenger cabin in an A321 is 3.7m - meaning a floor area of 114.7m2.

An 7W NMA with an equivalent passenger capacity would be about 32 rows giving 224 seats. That works out out to a passenger cabin length of approximately 26M plus an additional 1M for additional space in exit rows. Putting your cabin at 27M and 4.42M wide. That also means a floor area of 119.3m2 or 4% more with 1.8% more passengers. It's only a 2.1% difference per passenger in Single class. A 737 fuselage would be 109.74m2 so the A320 is 4,5% more than the 737 with the same number of passengers - a bigger delta than what a potential 7W would be.

However Boeing is calling it a 2 class airplane. By going 5W at roughly equivalent comfort to 4W you need 25% less length up front to accommodate the same number of seats - or if you squeeze in 6W up front with something like 20" seats which is doable you need 50% less.

Delta puts 24 seats up front in a 38" pitch on an 757 with 21" wide seats. That consumes 5.80M of cabin length - 5W would save you one meter and gain you an extra seat - meaning a cabin area of of 4.42m2 less putting you at barely more area than an A322 at 114.9m2 - .19% more.

At 6W up front you save 2M more in fuselage length and 8.84m2 of floor area - putting you a few percent under a potential A322.

Then you have to take into account the extra space you have in the ends. To get equivalent aero yes you would have to taper over a longer area. Let us assume the A322 ends are 16M long (47M -31M cabin). For the 7W you have 3% more fuselage height to taper (168"/163") and 18% more fuselage width (184"/156"). Lets call that 10.5%.

So the ends on the 7W are 17.7M putting your total 7W length at somewhere between 42.7M and 44.7M vs 47M for the A322.

That extra end space would be valuable adding somewhere around 7.0m2. You would use a little of that with the two narrower entries into the Ends - but that is less than 1m2 penalty. Leaving you 6.0m2 enough to take another row out in the cabin and easily cram them into the ends - meaning your 7W could now be 41.7M (Dual class 6W up front) to 43.7M (All Y) in length.

If I have time I'll do the skin area calculations next - but as you can see - there is not some huge penalty for 7W in terms of floor area - and in fact in 2 class there could be an advantage. In any case it is not more than the Delta between A320 and 737.

You basically pick up extra floor area for free by making a pencil fatter.

CRJockey wrote:

Revelation wrote:

CRJockey wrote:

I would hope that a sound business plan aiming for an existing and exploitable market niche would trigger programs and progress. Engine efficiency is a considerable but not all-deciding implication to that end.

You would hope, but in the real world A320neo happened because Airbus felt threatened by BBD C Series, and 737 MAX happened because Boeing literally was threatened to lose AA as a customer if it did not come up with a response.

How is this a "but"? In the "real world" Bombardier tried to exploit a market niche with a new product. Airbus and Boeing needed to protect their (ongoing exploitation of that very same) market niche and had the benefit of existing, more or less update-ready platforms.

The "but" comes in when you conflate "sound business plan" with CS. The likely response from A and B was well known, we talked about it at the time. GTF was a step change, the big boys were going to react. BBD had a small "first mover" advantage but decided to spend time and money on a new Lear and a new Global too. I remember Airbus putting the Pratt GTF on one of their flying testbeds. What was going to happen next was very obvious. Of course Pratt wasn't going to give BBD an exclusive.

BBD had to hope to use its first mover advantage well and not provoke a response too quickly (thus CS-100 before CS-300) and execute to plan to have any chance at all, and even that was wishful thinking. I remember threads saying "why not start with CS-300 then CS-500 and just deal with the inevitable response" but that's not how it played out.

morrisond wrote:

You basically pick up extra floor area for free by making a pencil fatter.

Er..... no. Fatter pencil is both heavier and has more drag, so not free.

Fred


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Revelation wrote:

CRJockey wrote:

Revelation wrote:

You would hope, but in the real world A320neo happened because Airbus felt threatened by BBD C Series, and 737 MAX happened because Boeing literally was threatened to lose AA as a customer if it did not come up with a response.

How is this a "but"? In the "real world" Bombardier tried to exploit a market niche with a new product. Airbus and Boeing needed to protect their (ongoing exploitation of that very same) market niche and had the benefit of existing, more or less update-ready platforms.

The "but" comes in when you conflate "sound business plan" with CS. The likely response from A and B was well known, we talked about it at the time. GTF was a step change, the big boys were going to react. BBD had a small "first mover" advantage but decided to spend time and money on a new Lear and a new Global too. I remember Airbus putting the Pratt GTF on one of their flying testbeds. What was going to happen next was very obvious. Of course Pratt wasn't going to give BBD an exclusive.

BBD had to hope to use its first mover advantage well and not provoke a response too quickly (thus CS-100 before CS-300) and execute to plan to have any chance at all, and even that was wishful thinking. I remember threads saying "why not start with CS-300 then CS-500 and just deal with the inevitable response" but that's not how it played out.

Hindsight knowledge. That’s easy. When the CS was conceived, probability is high that the business plan was sound. No „but“ required.

I'm not a proponent of 7 abreast dual aisle seating, but there's more to the calculation than more drag and added weight to the airframe.

You get 100% more aisle space for 15% more seats. (If you keep the aisles the same width).

That means faster embarking and disembarking, it means faster and more efficient service on board. It means faster cleaning and tighter turnaround. And it means more galley space or lavatory space in the width of the fuselage, which means you save some space length wise. You also increase overhead compartment space. And you get a roomier, more spacious cabin.

All of these things can be quantified, but I think it's more difficult to sell a concept airplane with these positives as long as it also adds weight and drag to the airframe. I do suspect airlines tend to look at the fuel burn and general economy of CASK.

I'm not a fan of 7 abreast (767 excepted) as they will either make it super tight or wide enough to fit super tight 8 abreast. If they are going to cram using narrow seat widths (and of course they will), then the best solution is 2-2-2. Everyone either gets an aisle or a window.