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dare100em
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 12:25 pm

Newbiepilot wrote:
keesje wrote:
I can't imagine a twin aisle being more efficient than a longer single aisle. Compare the same capacity, age, 757 and 762. OEW differs significantly.

A big single aisle, with wider fuselage/ aisle for quick deboarding and twin aisle premium class option, dedicated wingsets for short and medium range, could be a better compromise. Lighter anyway.


I think you overanalyzing the impact of fuselage width on weight of the airplane. The 767-200 has a wing that is 50% larger than the 757. It has the structure in the wing, wingbox and tail for 50% higher MTOW. That is why it is so much heavier.

The fuselage tube itself doesn't weight that much compared to the wing, wingbox, gear and tail. I don't have exact numbers, but I remember reading that he 737 fuselages coming in on the trains are only 1/7 of the total weight of the plane once it rolls out of the factory. Adding the wings, gear, engines, systems and interior is a large part of the weight. I wish I could find that source to double check if it is correct because I cannot verify it is true. I think his is why we are seeing an aluminum fuselage and composite wing on the 777x.

Finding the right balance of structural weight for the wing and its structure for how much payload the plane is going to carry is more difficult.


That's correct. To some degree the bigger cross-section means even less bending strain because the geometrical/area moment of inertia goes up faster then the frontal area, so the walls can be designed to be thinner in rsponse. The effect even increases further because at the same capacity a twin can be much shorter than a single aisle, lowering the beding stress of the parts of the fuse not supportet by the wing even more. This isn't taken into account in most discussion. The 767 and older dual aisles where as heavy for their capabilities, not for their fuse withness.
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 12:28 pm

But the size of the fuselage decides the payload you can carry. No point in having a wider fuselage and not being able to carry the payload to fill it. Then add the desired range and you come up with a design.

The payload of the single aisle will be smaller than that of the twin aisle. Trying to make a twin aisle with a A321 like payload, is pointless because aerodynamically your finesse ration will be unattractive and your fuselage weight will still be higher. In addition your rudder will be larger as it will be close to the centre, which will eat up a huge part of the general advantage of the wider fuselage when it comes to with standing bending forces.

In the end it would be the geometry of a A310-200/300. Even with modern technology, I doubt you could reduce the difference in weight to less than 20% against the A321 and less than 305 against a single aisle using similar technology.
 
frmrCapCadet
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 3:28 pm

http://www.seattletimes.com/business/bo ... they-hear/

This has more 'inside' discussion than anything I have seen so far. It makes the case for a twin aisle. And it predicts a market of 5000 planes.

My ps is still that it will ruin the now fractured possibility for the 787 to even approach break even. Then again, it could keep Boeing in business.
Buffet: the airline business...has eaten up capital...like..no other (business)
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 4:27 pm

70-80 Million for a 5200nm twin aisle with economics matching or better than a 787... sure
Last edited by seahawk on Thu Mar 09, 2017 4:56 pm, edited 1 time in total.
 
bhill
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 4:31 pm

Carpe Pices
 
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Polot
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 4:46 pm

seahawk wrote:
In the end it would be the geometry of a A310-200/300. Even with modern technology, I doubt you could reduce the difference in weight to less than 20% against the A321 and less than 305 against a single aisle using similar technology.


Indeed, so the key is if there is a big enough market, and if Boeing can keep costs under control enough, to develop a plane that will be difficult for Airbus to match with the A321/A320 family without major changes but also does not step too much on the 787.

The potential is there, even ignoring all other carriers just think about how much AA and especially UA/DL (they are going to need something smaller than the A339 eventually) would love the plane to replace/expand upon their 767 and TATL 757 fleets, and it would probably be attractive to LCCs with TATL ambitions, especially if dipping their toe into the pond is successful with the A321LR (A321LRs work, but in dense layouts will still be rather restricted to mostly the North Eastern US from Europe). It is just what the price to Boeing will be, and can they financially justify it.
 
Newbiepilot
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 5:06 pm

There is a lot of attention being put on Transatlantic flying. I think the bigger market for this plane is in Asia. There are many 737s and A320s flying around in China. Airspace and airports are crowded. Frequency is high on many routes. Currently there are 777s, 787s and A330s being used on 3 hour domestic flights and neighboring countries. Assuming a smaller long range and bigger shorter ranged derivative are offered, I could hundreds of bigger MOM planes sold in China. Eventually China won't be able to keep building more runways and with the population, I could see a MOM being very successful. This is what the original A300 was envisioned to do in Europe.

Another factor when discussing China is the impending COMAC planes. Sales campaigns for A320neos and 737MAX planes might start to be harder with government pressure to buy the C919. A MOM plane gives Boeing a larger plane that for now has no competitor from COMAC.
 
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keesje
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 5:15 pm

If Boeing makes a 5000NM twin aisle for the price of an A321 that would really put Airbus into problems.

And if your cat said woof it would be a dog.

Cutting edge technology defying physics / logic for the glory of the nation.

Just like in the movies, the public loves it.
"Never mistake motion for action." Ernest Hemingway
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 5:36 pm

They promised no more moonshots, so why not try for Mars?
 
Newbiepilot
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 5:48 pm

[photoid][/photoid]
keesje wrote:
If Boeing makes a 5000NM twin aisle for the price of an A321 that would really put Airbus into problems.

And if your cat said woof it would be a dog.

Cutting edge technology defying physics / logic for the glory of the nation.

Just like in the movies, the public loves it.


Are A321s actually selling for 70 or 80 million? The latest aircraft valuations thread had A321 numbers topping out at around 50 - 55 million. If sales price for an A321neo is in the 50-60 million range, then the MOM probably would only be able to sell for 70 or 80 million. These are actual prices and not list prices of course. I don't understand your reaction.
 
morrisond
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 5:57 pm

A 2x3x2 Oval Composite Barrel that takes LD3-45's with only about 16% more surface area (160" H x 185"W Oval) using 787 Tech is not a Moonshot. Use what you learned on the 787/777X and use that tech/systems architecture, wing Aero. The only thing new would be the Oval barrel - But they have been playing with that for years and they should have a pretty good handle on how to build it by now and how strong it is. This could be within 10% of the weight of an A321 (assuming wing sized for same mission). You gain 1 Seat per row which means a shorter aircraft for the same capacity and more room up front so you might be able to 2x1x2 Bus adding more seats as well. The Oval might help you with Aero as well generating more lift. Definitely doable for 2025 assuming they have the Barrel figured out already and an Engine can be ready in time.
 
airzona11
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 6:04 pm

As others have noted above, the composite barrel, and knowledge learned from other aircraft projects is going to be key here. If we are talking ~7 years from now, might not be a moonshot. The size of the wing will be interesting. If it slotted for 757/767 gates, vs the smaller box of A320/737 that negates a lot of issues. The problem the 787 had for airlines like UA was that the wingspan was larger than the slotted space for a 767.
 
PlanesNTrains
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 7:01 pm

A350 wrote:
Altogether the advantages are very clear, but is there enough margin that they can pay for the development of a clean-sheet design and an additional aircraft family at the airline's fleets? I'm not yet convinved


Nobody is, including Boeing. That's why we're still waiting. :-)
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
morrisond
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 8:32 pm

airzona11 wrote:
As others have noted above, the composite barrel, and knowledge learned from other aircraft projects is going to be key here. If we are talking ~7 years from now, might not be a moonshot. The size of the wing will be interesting. If it slotted for 757/767 gates, vs the smaller box of A320/737 that negates a lot of issues. The problem the 787 had for airlines like UA was that the wingspan was larger than the slotted space for a 767.


Put Folding Wingtips on the 2x3x2 Oval and it would fit in A320/737 gates no problem at all and Boeing has already figured out the tech - it could make it very efficient and a great TransAtlantic Frame.

That may be what is making some of the Airlines very happy - Folding tips getting a nice long wingspan into Existing gates.

You might not need 40-45K of Thrust either with a nice long wing, 38-40 Might do it.
 
iamlucky13
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 8:38 pm

frmrCapCadet wrote:
http://www.seattletimes.com/business/boeing-aerospace/boeings-talking-with-airlines-about-a-797-and-they-like-what-they-hear/

This has more 'inside' discussion than anything I have seen so far. It makes the case for a twin aisle. And it predicts a market of 5000 planes.

My ps is still that it will ruin the now fractured possibility for the 787 to even approach break even. Then again, it could keep Boeing in business.


5000 sales has been mentioned before, but depending on the source, it sounds like either the absolute top end of the possible demand, or 5000 sales for the entire mid-market segment, including A321LR's and A330 NEO's. For example:
https://www.flightglobal.com/news/artic ... -a-427527/
Boeing estimates that a 20-year market for at least 2-3,000 aircraft, and perhaps as many as 4-5,000 units "if you build a really good airplane", says Tisneth.


Basically, Boeing has to convince themselves the program can turn a worthwhile profit at 2000 frames.

There will likely be nearly 1500 787's in service before the MoM is even available, and the 787-9 and 787-10 will still be much more capable aircraft. I wouldn't worry too much about the effect of this program on the 787. Besides, by then I think there's good chances Boeing will be starting to think about a mid-life upgrade for the 787.

keesje wrote:
If Boeing makes a 5000NM twin aisle for the price of an A321 that would really put Airbus into problems.


It's a safe assumption it won't be the price of an A321. It might have the CASM of an A321 due to having more seats, but I'm not even sure of that. It must have a better CASM than a 788 or A330 NEO on similar stage lengths. If it can't even achieve that, it has no hope, but I don't know why it shouldn't be able to.

It could hypothetically have slightly worse CASM than the A321LR, but still win some sales campaigns against that model due to greater route flexibility.
 
iamlucky13
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 9:13 pm

morrisond wrote:
A 2x3x2 Oval Composite Barrel that takes LD3-45's with only about 16% more surface area (160" H x 185"W Oval) using 787 Tech is not a Moonshot. Use what you learned on the 787/777X and use that tech/systems architecture, wing Aero. The only thing new would be the Oval barrel - But they have been playing with that for years and they should have a pretty good handle on how to build it by now and how strong it is. This could be within 10% of the weight of an A321 (assuming wing sized for same mission). You gain 1 Seat per row which means a shorter aircraft for the same capacity and more room up front so you might be able to 2x1x2 Bus adding more seats as well. The Oval might help you with Aero as well generating more lift. Definitely doable for 2025 assuming they have the Barrel figured out already and an Engine can be ready in time.


I was just playing with some simplified geometry - based on the Wikipedia numbers for the A321 of 240pax at 28", that's 1120" length of the seating area. For a 156" x 163" ellipse, that's 3898 sq ft of skin surrounding the cabin.

Suppose for the MoM we widen the fuselage by 1 x 18" seat and 1 x 21" aisle compared to the A321. That's 195" (pretty similar to 198" for the 767). To fit the same number of seats in at the same pitch with the same fuselage height, the elliptical calculation indicates 3756 sq ft of skin around the cabin.

That's 4% less skin than the A321 for the same number of seats, although obviously not accounting for the nose and tail taper and numerous other factors. The weights could be extremely close, except for the fact that Boeing is targeting more range.

The big negative aside from the heavier frames to maintain the oval shape is the frontal area is 25% greater.
 
WaywardMemphian
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 9:21 pm

Has anyone brought up the possible freight only model aspect of this.

How would this plane fit in at FedEx in a freight role.
 
kurtverbose
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 9:22 pm

Just remember, Airbus will have a lot more scope to drop the price of the A321/2 than Boeing will with a 789.
 
airzona11
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 9:25 pm

morrisond wrote:
airzona11 wrote:
As others have noted above, the composite barrel, and knowledge learned from other aircraft projects is going to be key here. If we are talking ~7 years from now, might not be a moonshot. The size of the wing will be interesting. If it slotted for 757/767 gates, vs the smaller box of A320/737 that negates a lot of issues. The problem the 787 had for airlines like UA was that the wingspan was larger than the slotted space for a 767.


Put Folding Wingtips on the 2x3x2 Oval and it would fit in A320/737 gates no problem at all and Boeing has already figured out the tech - it could make it very efficient and a great TransAtlantic Frame.

That may be what is making some of the Airlines very happy - Folding tips getting a nice long wingspan into Existing gates.

You might not need 40-45K of Thrust either with a nice long wing, 38-40 Might do it.


Very good and interesting point. Would love to see some mockups. I really hope we get to see a tangible plane!
 
morrisond
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 9:44 pm

iamlucky13 wrote:
morrisond wrote:
A 2x3x2 Oval Composite Barrel that takes LD3-45's with only about 16% more surface area (160" H x 185"W Oval) using 787 Tech is not a Moonshot. Use what you learned on the 787/777X and use that tech/systems architecture, wing Aero. The only thing new would be the Oval barrel - But they have been playing with that for years and they should have a pretty good handle on how to build it by now and how strong it is. This could be within 10% of the weight of an A321 (assuming wing sized for same mission). You gain 1 Seat per row which means a shorter aircraft for the same capacity and more room up front so you might be able to 2x1x2 Bus adding more seats as well. The Oval might help you with Aero as well generating more lift. Definitely doable for 2025 assuming they have the Barrel figured out already and an Engine can be ready in time.


I was just playing with some simplified geometry - based on the Wikipedia numbers for the A321 of 240pax at 28", that's 1120" length of the seating area. For a 156" x 163" ellipse, that's 3898 sq ft of skin surrounding the cabin.

Suppose for the MoM we widen the fuselage by 1 x 18" seat and 1 x 21" aisle compared to the A321. That's 195" (pretty similar to 198" for the 767). To fit the same number of seats in at the same pitch with the same fuselage height, the elliptical calculation indicates 3756 sq ft of skin around the cabin.

That's 4% less skin than the A321 for the same number of seats, although obviously not accounting for the nose and tail taper and numerous other factors. The weights could be extremely close, except for the fact that Boeing is targeting more range.

The big negative aside from the heavier frames to maintain the oval shape is the frontal area is 25% greater.



I think that is one of the benefits of using Composite in this size class - it has excess strength to handle impact loads so the penalty might not be so bad.

Try an elipse with a width of 185" (Assume 737/787 seat Widths and two 18" aisle's and you save 9"), I think it is only a 16% frontal area penalty - Not far off the Delta of the 320 vs 737 and that doesn't seem to hurt the 320 that much...

Plus you might get some extra lift out of the oval offsetting the drag.
 
iamlucky13
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 10:09 pm

morrisond wrote:
I think that is one of the benefits of using Composite in this size class - it has excess strength to handle impact loads so the penalty might not be so bad.

Try an elipse with a width of 185" (Assume 737/787 seat Widths and two 18" aisle's and you save 9"), I think it is only a 16% frontal area penalty - Not far off the Delta of the 320 vs 737 and that doesn't seem to hurt the 320 that much...

Plus you might get some extra lift out of the oval offsetting the drag.


I think the composite tradeoffs are the other way around - excellent tensile strength for hoop stress and bending loads, but has to be thicker than those considerations alone indicate in order to meet impact requirements.

I went wide to be somewhat conservative. Your suggestion sounds aggressive. I tend to expect something in the middle. However, A 185" x 163" ellipse yields 18.6% larger frontal area and 6.4% less skin area than a 156" x 163" ellipse.
 
morrisond
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 10:38 pm

Maybe I didn't phrase it correctly - wouldn't the thicker composite skin necessary for impact loads give you even greater strength to resist the Oval fuselage trying to make itself back into a circle?
 
flipdewaf
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 10:39 pm

H o w does the oval fuselage affect shoulder space?
Image
 
AirbusA6
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 10:44 pm

frmrCapCadet wrote:
http://www.seattletimes.com/business/boeing-aerospace/boeings-talking-with-airlines-about-a-797-and-they-like-what-they-hear/

This has more 'inside' discussion than anything I have seen so far. It makes the case for a twin aisle. And it predicts a market of 5000 planes.

My ps is still that it will ruin the now fractured possibility for the 787 to even approach break even. Then again, it could keep Boeing in business.


As an aside I was interested in this quote from the article

Udvar-Hazy said the key to going forward will be development of a suitable engine with 40,000 to 45,000 pounds of thrust. He said he expects Boeing to offer a choice of two engines, likely one from GE and another potentially from a Pratt & Whitney/Rolls-Royce joint venture.


That's the first I've heard of a PW/RR joint venture, IAE mark 2?
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keesje
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 11:13 pm

Newbiepilot wrote:
[photoid][/photoid]
keesje wrote:
If Boeing makes a 5000NM twin aisle for the price of an A321 that would really put Airbus into problems.

And if your cat said woof it would be a dog.

Cutting edge technology defying physics / logic for the glory of the nation.

Just like in the movies, the public loves it.


Are A321s actually selling for 70 or 80 million? The latest aircraft valuations thread had A321 numbers topping out at around 50 - 55 million. If sales price for an A321neo is in the 50-60 million range, then the MOM probably would only be able to sell for 70 or 80 million. These are actual prices and not list prices of course. I don't understand your reaction.


I have no idea what you mean Newbiepilot. The prices are online, distract a 30% discount and here we are. More than 50% discount for an A321?
http://www.airbus.com/presscentre/pressreleases/press-release-detail/detail/2017-price-adjustment-for-airbus-modern-fuel-efficient-aircraft/
"Never mistake motion for action." Ernest Hemingway
 
Newbiepilot
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Re: Airlines interested in Boeing MOM concept.

Thu Mar 09, 2017 11:30 pm

Keesje, I think you know what I mean since you commented in the airplane valuations thread. When they mention $70-80 million being the price the market will accept for a MOM plane, I assume they are referring to actual price and not list. Actual A321 prices top out around $50 million according to the blue book numbers posted here:

viewtopic.php?t=1345101
 
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Devilfish
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 2:28 am

This article tells of airline support for the MoM.....

http://www.flightglobal.com/news/articl ... om-434961/
"Everyone is entitled to my opinion." - Garfield
 
 
ikramerica
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 2:45 am

morrisond wrote:
A 2x3x2 Oval Composite Barrel that takes LD3-45's with only about 16% more surface area (160" H x 185"W Oval) using 787 Tech is not a Moonshot. Use what you learned on the 787/777X and use that tech/systems architecture, wing Aero. The only thing new would be the Oval barrel - But they have been playing with that for years and they should have a pretty good handle on how to build it by now and how strong it is. This could be within 10% of the weight of an A321 (assuming wing sized for same mission). You gain 1 Seat per row which means a shorter aircraft for the same capacity and more room up front so you might be able to 2x1x2 Bus adding more seats as well. The Oval might help you with Aero as well generating more lift. Definitely doable for 2025 assuming they have the Barrel figured out already and an Engine can be ready in time.



2-4-2 is the way to go. Not luxurious 2-4-2 but 17.2" seat and narrower aisle 2-4-2. It's about 10" wider than the 767, which still allows a non-cramped 2-2-2 J or domestic F (vs a cramped 2-2-2 J or 2-1-2 F) and a 1-1-1 lie flat product.

This again allows for 763 capacity in a shorter plane, and 764 capacity in an aircraft only slightly longer than the 763. Those are today's MoM capacities. Otherwise you are in A333/789 territory or A321 territory.
Of all the things to worry about... the Wookie has no pants.
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 5:57 am

Newbiepilot wrote:
Keesje, I think you know what I mean since you commented in the airplane valuations thread. When they mention $70-80 million being the price the market will accept for a MOM plane, I assume they are referring to actual price and not list. Actual A321 prices top out around $50 million according to the blue book numbers posted here:

viewtopic.php?t=1345101


Yes, CEOs that are available on the market as the original buyer did not take them up.

A NEO will go for about 10 Million more. So lets say 60-65 million, which means airlines would only take the MoM if it is not more than 20% more expensive than a A321NEO. Reaching this price level and the required performance level will be a challenge and a huge risk for Boeing. And even if they achieve those goals it will kill their 787 margins and it will be hard to meet the numbers they need to get rid of the deferred costs.
 
iamlucky13
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 6:43 am

morrisond wrote:
Maybe I didn't phrase it correctly - wouldn't the thicker composite skin necessary for impact loads give you even greater strength to resist the Oval fuselage trying to make itself back into a circle?


Ah, I see what you're saying. Unfortunately, no. I'm fairly certain a thicker skin offers little to no benefit for the bending resistance necessary to maintain the ovalized shape.

However, the fuselage frames that perform this function are only a small fraction of the structural weight of the plane, and I suspect thickening the frame flanges and possible increasing the frame chords slightly will account for a relatively small percentage of the weight. I expect frontal area to be the bigger drawback.
 
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Matt6461
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 8:29 am

ikramerica wrote:
2-4-2 is the way to go. Not luxurious 2-4-2 but 17.2" seat and narrower aisle 2-4-2. It's about 10" wider than the 767, which still allows a non-cramped 2-2-2 J or domestic F (vs a cramped 2-2-2 J or 2-1-2 F) and a 1-1-1 lie flat product.


Totally agree. 8 17.2" seats, 11 2" armrests, and 2 18' aisles = 195.6in. Call it 196in but maybe 194/195in with 17in aisles.
If it's a circular fuse and Boeing can use the 777X's 4in sidewalls at the critical points, that's a 204in fuselage. Call it 208in just to be safe (6in sidewalls and 18in aisles).
At 208in, diameter and wetted area per seat for Y cabin is equal to the A320's upper bubble ( 8/6 * 156in); total wetted area is less including A320's belly bulge.
Compared to A300/330/340, same Y seats abreast for 6.3% less wetted area (8.1% less if 204in diameter).

So basically there's extremely little - if any - wetted area penalty for a feasible 8ab circle measured against A320. More if measured against 737. Seat width is smaller than A320 but I'd trade 2-4-2 and an inch of width against 3-3. Most probably would. In addition to the seated experience, the boarding/deplaning process would be better for pax and airlines.

For the smallest family member at around A321 capacity (240 seats at 28in pitch), minimum parallel cabin length would be ~71ft (assuming non-parallel portions contain only lavs/galleys, +1ft for exits).
In fact you'd squeeze 3-4 rows at 7ab into the tapering sections, especially aft where the taper is more gradual. That would mean A321-scaled capacity is ~261-268 seats.
So the smallest member would sit ~8-12% above A321 capacity - about where it should be.
Assuming nose- and tail-cone fineness ratio of 1.6 (standard) and 2 respectively, total fuse length would be ~133ft. Fuse fineness ratio would be 7.7 - low but not fatal.
One of the biggest drawbacks of stubby fuselages is lower moment arm for the empennage. For this generation of aircraft, however, with lower weights and thrust levels, empennage will be significantly smaller (plus advances in FBW allowing smaller control margins).
A310's rudder, for example, handled up to 58k thrust per engine. Here we won't go much over 40k. MTOW will be much, much lower (less wing lift = less HTP lift = smaller HTP).
The possibility of using the 789's HLF tech for the rudder further reduces the concern about empennage size (this was seen as a wash for 779, which has proportionately less rudder impact due to much longer moment arm).

So it seems clear that a small twin-aisle can be as efficicient as the A320 even before we get to the weight savings of a stubby tube versus a long narrow one, CFRP/NewMetal vs. old metal.
That's what the airlines are probably learning via Boeing's presentations.
An 8ab circle would lose LD3 ability, but LD3-45's are doable and we've already seen plans to use even MAX-8's extensively on TATL. So I don't think cargo is going to tip this picture, especially with an inevitable trend of declining yields as cargo prices approach the marginal cost of filling the world's burgeoning belly capacity (i.e. very low).

And that's just for the smallest family member of A321 plus ~10% size. The next-largest member at ~753/762 size is even more optimal.

I have no idea whether an oval would be better than the above-sketched 8ab circle - whether 7ab or 8ab. It doesn't need to be better IMJ; if it is that's just gravy.

I never bought the line that it HAD to be priced at ~$70mil.
A plane's value proposition is the sum of its life-cycle costs and revenues. Boeing can change the price at which its products sell by making them more or less fuel- or otherwise efficient.
The idea of a fixed $70mil cost was a bit like airlines saying it had to be CFRP - maybe it does but let Boeing figure that out.
Likewise, let Boeing figure out at what airline cost in capital it can offer airline savings on fuel and other expenses, explain the numbers to airlines, and see what sells.
We're now hearing that $80mil could be the price target; we may see a higher willingness to pay - especially for the larger version(s).

IMO a baseline at ~A321+10% size and a stretch at ~753/762 size - both with MOM range - could be followed by a further stretch approaching A332 size with only transcon range. That kind of plane could end up dominating domestic/regional trunk routes - no small market.

What's the business case for Boeing? Say they'll spend $15bil and want 20% annual ROI at production maturity - $3bil profit per year.
If they build 200/year, they'd need $15mil/plane. If the plane sells at $80mil, that's 19% profit margin. Doable...

Still you have to be aggressive to close that business case, especially given the risks inherent in airliner programs and especially given 787 PTSD.
Maybe 20% ROI is too low a minimum. At 30% it's harder to see.
I think everyone looking at this seriously sees it would be a great plane for airlines and would yield serious production profit for Boeing.
The only open question seems to be whether there's a sufficient ROI for a big new program.
I hope they launch but can't say for certain I'd bet my job on it were I in the nice offices in Chicago.
 
hz747300
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 9:01 am

What's wrong with a 757 with the composite skeleton, advanced avionics and new engine? They can even build in front & back airstairs and call it the 7-awesome-7.
Keep on truckin'...
 
dare100em
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 9:18 am

@MATT

That's exactly the point. They'll build a plane capable of a sardine 2-4-2 (17” seats, 1,5” armrest, about 20” aisle) and LD3/45. The more- and more common Y+ class will get 2-3-2 with 19” seats, 2” armrests and 21” aisles. Plus the option for 1-1-1 in business. The fuse witness could be even narrower than a 767. This plane won’t have any penalty to an A320. It is a perfect plane for the expansion of LCC to medium-long flights. Furthermore it would be great as an all Y bus for intra-Asia stages no longer than 4 hours. In such configurations the MOM could haul 350 people plus at extreme favourable CASM plus short boarding – deboarding and turnaround times.
There are many points which could make such an MOM a real success, killing all hope for anything below an A330-900neo. Furthermore by going this direction Boeing is much safer regarding anything Airbus can do with an A312neo² or A322 (new Wing, 40+ m fuse). By doing just a 3-3 configuration the threat would be totally different.

The main challange is to control the costs to build such a plane. I has to be in the 80-90 m (assuming 60 m for an A321neo) ballpark wich will be really hard to achieve.

hz747300 wrote:
What's wrong with a 757 with the composite skeleton, advanced avionics and new engine? They can even build in front & back airstairs and call it the 7-awesome-7.


A composite 757? Come on, it's even confusing where to start to list the drawbacks of such a move. The 757 is conceptual limited in so many ways for todays standarts (as is the 767 to a lesser degree) that hell will freeze before an Franken 757Max occurs.
 
strfyr51
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 9:49 am

Boeing Has probably gone as ar as they want to on the B767 type certificate. The MoM concept could put them in an Entirely NEW classification where they might develop an entirely NEW family of airplanes in the same vein they Used the B767-400 , he incremental changes they put in the B767-400 made that airplane closer to the B777 than it did the B767-300 in Avionics, cockpit design and some systems. If they Release the MOM? This could be he Basis for small wide-bodies for another 2 decades especially with Fly-by wire and fly by light flight controls.
Boeing is merely positioning themselves for the future as we cannot know if this will just be a New airplane? Or the start of a New airplane Family in innovation. As a Nearly 50 year aviation technician (1970-present) many of the systems I started with are far in advance of the systems I trained in 1970 . Alcoa 2024 has become Aluminum-Lithium
dope and fabric has become wound composite, Cable controlled flight controls has become Fly-by Wire and fly by Light Inertial Navigation has gone from Flux valves an Gacs to Ring Laser Gyros ( included in the platforms themselves. So much has changed that Boeing has had to replace entire certifications and categories of certifications.
The B767 can no longer be a derivative to anything New except for the size of it, (which it appears is the Basis for the MoM airplane. I suspect Airbus is at the end of the A300 Tree as well.
 
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KarelXWB
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 9:49 am

Newbiepilot wrote:
Keesje, I think you know what I mean since you commented in the airplane valuations thread. When they mention $70-80 million being the price the market will accept for a MOM plane, I assume they are referring to actual price and not list. Actual A321 prices top out around $50 million according to the blue book numbers posted here:

viewtopic.php?t=1345101


Airbus charges a premium for the NEO. If the A321 sells for $50 million, the A321neo would be 10-15% more expensive.

frmrCapCadet wrote:
http://www.seattletimes.com/business/boeing-aerospace/boeings-talking-with-airlines-about-a-797-and-they-like-what-they-hear/

This has more 'inside' discussion than anything I have seen so far. It makes the case for a twin aisle. And it predicts a market of 5000 planes.

My ps is still that it will ruin the now fractured possibility for the 787 to even approach break even. Then again, it could keep Boeing in business.


Right, if there is a market for 5,000 airplanes Boeing would have launched the thing already. This figure comes at the expense of A321s, 737-9/10s, A330s and 787s though it would be naive/unrealistic to believe the MOM aircraft would take all the sales. Looking at the 757 market and taking some growth and new routes into account, an outlook for 1,500 airplanes over a period of 20 years sounds more realistic.
What we leave behind is not as important as how we've lived.
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 9:59 am

Sure, nearly A332 size in single class with 5000nm+ range, without any disadvantage against the A321....
 
dare100em
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 10:07 am

seahawk wrote:
Sure, nearly A332 size in single class with 5000nm+ range, without any disadvantage against the A321....


OFC there are disadvantages, but it's not as severe as some allways thought it is. "It only can be a single aisle" is just an to easy assumption. And of course if it is designed as a people mover for LCC's and intra-asia you just don't need to grow lift and bulk cargo capabilities the same way you did in the past or with an A330. For that role you allready have A330neo and 787-9. So you end up with a much lighter design and only LD3/45 capabilities. You just need enough belly space to lift the bags, anything beyond is a plus. For intra-asia there won't be any cargo moved, in longer range configurations of Tier 1 carriers you'll have less density and more Y+, J, so you'll have some room for cargo.

It can't be working because I'll told you all the time it won't :roll: Let's wait and see :D
 
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KarelXWB
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 10:13 am

iamlucky13 wrote:
It's a safe assumption it won't be the price of an A321. It might have the CASM of an A321 due to having more seats, but I'm not even sure of that. It must have a better CASM than a 788 or A330 NEO on similar stage lengths. If it can't even achieve that, it has no hope, but I don't know why it shouldn't be able to.


A narrowbody price tag doesn't make much sense, it would cannibalize the upper part of the 737 market.

And a low production rate (1,000 - 1,500 aircraft over a period of 20 years equals some 50 - 75 aircraft per year) is not going to help pressing the price. I suspect airlines are going to pay a premium for this aircraft if it offers unique capabilities.

It shows why Boeing still hasn't figured out a viable business case. Why would they invest $10 billion into such program? There are always alternatives. Without a MOM aircraft, airlines would be happy to buy additional 787s.

It could hypothetically have slightly worse CASM than the A321LR, but still win some sales campaigns against that model due to greater route flexibility.


:checkmark:
What we leave behind is not as important as how we've lived.
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 10:14 am

Something able to haul 350 pax in single class configuration is no competition to the A321 anyway.
 
dare100em
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 10:52 am

seahawk wrote:
Something able to haul 350 pax in single class configuration is no competition to the A321 anyway.


That's the whole point of the MOM and this strategy is correct IMO. We allready discussed that month ago and even than my opinion - and that of other like Matt - was that the MOM is not a better A321.5neo with 500 nm more range. A clean-sheet development exactly the size or even slightly larger than a A321 (A322) woul be a serious risk because Airbus could very easily build a A321.5neo and A322neo combination with a bigger wing for 3-4 billion $. But the MOM as it turns out can't be easily counteres by that. An A322 may be inevitable anyway and make it more challenging to close the business case but still the MOM will be in another class and rightly so. Furthermore it will force Airbus to put ressources an the A330 size or slightly below because after the introduction of the (larger) MOM it's scope will be very narrow.
 
parapente
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:11 am

People seem to think that 2X4X2 twin aisle is the most likely config.With a very high aspect wing with fuel for 5k miles.They are stating pax as circa 240.If one class that's just 30 rows of seats.Is that not rather short (thus not aero optimal) for this class of WB aircraft?
Am no expert (at all!) but would look rather stubby particularly with such long wings- no?
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:17 am

parapente wrote:
People seem to think that 2X4X2 twin aisle is the most likely config.With a very high aspect wing with fuel for 5k miles.They are stating pax as circa 240.If one class that's just 30 rows of seats.Is that not rather short (thus not aero optimal) for this class of WB aircraft?
Am no expert (at all!) but would look rather stubby particularly with such long wings- no?


Image

https://www.seatguru.com/airlines/Air_T ... 10-300.php
 
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SomebodyInTLS
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:19 am

morrisond wrote:
I think that is one of the benefits of using Composite in this size class - it has excess strength to handle impact loads so the penalty might not be so bad.


Excuse me?!? Invisible delamination resulting from impacts is THE achilles heel of CFRP! The main reason single-aisle composite fuselage has largely been avoided till now is precisely because it will need to be overbuilt wrt. aircraft loads simply so it can handle the damage from ramp-rash, dropped tools, FOD from runways, hail, etc.

Edit: okay, I read the later explanation of what you meant.
Last edited by SomebodyInTLS on Fri Mar 10, 2017 11:35 am, edited 2 times in total.
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keesje
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:21 am

If we consider the flattened 2-3-2 fuselage (MOM7-200) , further improvements might be possible.

E.g. you could consider making the cabin a little higher, even circular. (NLT7-200)

It removes a lot of dead weight, all the bending fighting structure can be removed, saving weight & fuel while improving comfort.

Image

You could even consider removing 1 seat + 1 aisle and make the aircraft 20% longer. (NSA6-200)

In the 180-250 seat bracket that's very well possible.

That also improves the available space for revenue cargo pallets by at least 40% (assuming half is used for luggage) .
"Never mistake motion for action." Ernest Hemingway
 
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SomebodyInTLS
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:30 am

iamlucky13 wrote:
morrisond wrote:
Maybe I didn't phrase it correctly - wouldn't the thicker composite skin necessary for impact loads give you even greater strength to resist the Oval fuselage trying to make itself back into a circle?


Ah, I see what you're saying. Unfortunately, no. I'm fairly certain a thicker skin offers little to no benefit for the bending resistance necessary to maintain the ovalized shape.

However, the fuselage frames that perform this function are only a small fraction of the structural weight of the plane, and I suspect thickening the frame flanges and possible increasing the frame chords slightly will account for a relatively small percentage of the weight. I expect frontal area to be the bigger drawback.


Isn't the problem actually going to be that you need much stronger connections between frames and skin? With a circular fuselage, almost all the skin load is parallel to its surface - the frame is only there in a supportive role (literally). With the horizontal-oval fuselage, the skin under pressurisation will be trying to peel off the frames at the top and bottom. I imagine that if that is significant then you're going to need a different solution than typical fasteners or even bonding. Something like smoothly integrated frame/skin sections. And that would require another step forward in manufacturing.
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
Someone83
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:35 am

One thing is the frame (and wings) needed, but there is as well a question of available or potential engines. Right now there is no suitable engines on the market and a rather large fuel savings is probably wanted
 
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seahawk
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:37 am

It would be wide oval with a low floor, which would be so not nice when you look at the load distribution.
 
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KarelXWB
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:43 am

Someone83 wrote:
Right now there is no suitable engines on the market and a rather large fuel savings is probably wanted


Though new generation engines like the P&W GTF V2 and RR UltraFan are under development and should be ready by 2025.
What we leave behind is not as important as how we've lived.
 
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keesje
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Re: Airlines interested in Boeing MOM concept.

Fri Mar 10, 2017 11:51 am

The more I see about the consequences of a 2-3-2 cabin and people mention a bigger cross isn't all that detrimental, the more I lbegin to like the concept of a big narrowbody, solving some of the typical long NB cabin disadvantages (cabin) while retaining single aisle advanatges (economics) .

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