Moderators: richierich, ua900, PanAm_DC10, hOMSaR
iceberg210 wrote:seahawk wrote:Revelation wrote:I don't think it will take eight years to make a LEAP derivative, and from what we read that's the most likely launch engine.
Only if you can achieve the performance goals with an engine only half a generation more advanced than the competition. Being 2 years later might be preferable if the engine gives you another 5% fuel burn reduction.
Blind speculation on my part but I think it'll be launched with two options for engines, LEAPX+ and EITHER Ultrafan or GTF. But the latter two will have a two year later EIS. Maybe the way you get tricky with it is make the 797-7 the launch model with the 8 following with the two engine options while the 7 gets the engine option later. We'll just have to see...
Randy Tinseth, Boeing’s vice president of marketing for commercial planes, said the company was reluctant to change the design because larger wide body jets were better suited for cargo.
“We don’t want to over design an airplane just to carry belly cargo, especially when I can make an airplane that becomes more efficient delivering and carrying passengers,” he told Reuters on the sidelines of a global airlines meeting.
Stitch wrote:I'm going to hazard a guess that the preferred design cannot take dual LD3s and that is where the ask was from some customers. I still want to think we're looking at LD2/LD8 (ala the 767) more than LD3-45/AKH like on the A320 family (and assuredly NSA).
ITB wrote:I haven't seen this mentioned yet. In the FlightGlobal article "Boeing still on track to 2025 NMA – despite engine makers’ travails," published yesterday online, Randy Tinseth is quoted as saying this:
“We have an airplane between today's widebodies and today's single aisles. It won't look like either of them. When we take a look at what our customers want and need in this market, there no question that efficiency is critical. When a widebody airplane is operated on these shorter missions - the mission potentially of an NMA – they are over capable. With the ability to carry heavy cargo comes weight, structure, and inefficiency.”
Interesting. Boeing now has an airplane concept between a widebody and a single aisle, but "It won't look like either of them." What exactly does Tinseth mean with this statement? Is he saying the 797 will be significantly different, design wise, from today's airliner? Probably not. But still.
Source: https://www.flightglobal.com/news/artic ... ne-449146/
morrisond wrote:I'll say it again as I've said many times - NMA will most likely be an 2x3x2 Oval with a Container something like a 2' Wider LD3-45 in the belly - maybe 5-6" higher. Then they can reuse the Cross Section and Nose for NSA. It just makes a lot of sense.
parapente wrote:The statements from Boeing seem to indicate that the decision to offer will be put back a year due to the stresses on the OEM engine manufacturers-although it could be a smoke screen
I thought it odd that he said the decision could go back a year -on an already tight timescale yet the EIS is not put back.They are going to have to work mighty fast.It perhaps suggests that both the wing and engine are scaled versions of existing wings?As for cargo -the design must be frozen by now -certainly the major decisions do it is what it is.I think they will be well advised to put pax economics before cargo volume.
Hell airlines can always buy the 788 if it means that much to them.
Revelation wrote:He also says that Boeing has discussed the project with 60 airlines and he downplays the idea that the product may be launched at Farnborough.
QuarkFly wrote:
Except that kind of cross section would not make any sense at all for a NSA narrow-body. Too much frontal area, and weight for only one more seat per row than a 6-acoss single-isle aircraft. And I doubt you could just put a shorter range wing on that larger center wing box.
QuarkFly wrote:morrisond wrote:I'll say it again as I've said many times - NMA will most likely be an 2x3x2 Oval with a Container something like a 2' Wider LD3-45 in the belly - maybe 5-6" higher. Then they can reuse the Cross Section and Nose for NSA. It just makes a lot of sense.
Except that kind of cross section would not make any sense at all for a NSA narrow-body. Too much frontal area, and weight for only one more seat per row than a 6-acoss single-isle aircraft. And I doubt you could just put a shorter range wing on that larger center wing box.
(Ihssane Mounir, senior vice-president for commercial sales and marketing at Boeing) said the new mid-market plane would focus on what he described as a “revolutionary production system” incorporating new digital technology.
“It’s not a plane that will be technologically much more advanced than what we have today. What will be very advanced is the production system,” Mounir said.
“Based on where we are today, we are very comfortable with the fact we can do it by 2025, but we haven’t made a decision.”
Mounir said “conservative” estimates showed global demand for 4,000 to 5,000 middle-of-the market jets over 20 years.
Revelation wrote:The part I found most interesting was:.(Ihssane Mounir, senior vice-president for commercial sales and marketing at Boeing) said the new mid-market plane would focus on what he described as a “revolutionary production system” incorporating new digital technology.
“It’s not a plane that will be technologically much more advanced than what we have today. What will be very advanced is the production system,” Mounir said.
QuarkFly wrote:Hmmm, seems like only about 15 years ago, B was talking about the 787 production system....designed both digitally and globally, much fewer fasteners, would snap together on the line with the help of MOATT's (Mother of all Tool Towers), huge reduction in cost due to modern networked IT, etc etc...
Aircraft are not virtual...they need to be designed, tested, certified and built at a reasonable cost. Nobody can digitize their way out of a business case, solid aerospace engineering, safety and efficient production -- nor should they be allowed to !!
Revelation wrote:
I think the 797 approach is a lot more rational than the 787 approach.
Revelation wrote:I think the 797 approach is a lot more rational than the 787 approach.
Jon Ostrower
@jonostrower
2h2 hours ago
Boeing eyes 1Q19 for board authority to start selling new NMA https://theaircurrent.com/industry-stra ... uce-goose/ … (via @theaircurrent)
Revelation wrote:For what it's worth, in https://twitter.com/jonostrower/status/ ... 0885094401 we read:Jon Ostrower
@jonostrower
2h2 hours ago
Boeing eyes 1Q19 for board authority to start selling new NMA https://theaircurrent.com/industry-stra ... uce-goose/ … (via @theaircurrent)
So, as late as March 31, 2019?
mffoda wrote:Well they have the 797 trademark ready to go.
See FG link.
https://www.flightglobal.com/news/artic ... rk-450071/
Revelation wrote:
Revelation wrote:For what it's worthJon Ostrower
Boeing eyes 1Q19 for board authority to start selling new NMA https://theaircurrent.com/industry-stra ... uce-goose/ … (via @theaircurrent)
So, as late as March 31, 2019?
Boeing has quietly registered the name ‘797’ as a trademark, European intellectual property documents show.
The US airframer’s application, from its Seal Beach facility, gives little context for the registration beyond identifying that it would cover a range of items including aircraft and aeronautical equipment.
Revelation wrote:FG: Boeing secures '797' trademark
Most have expected this, but some of our a.net numerologists might be disappointed.
seabosdca wrote:If there will be two separate fuselages for this and NSA (as seems quite likely) then one assumes there will be two separate model numbers. And 777-787-797 for the widebodies is such a clean progression, but there is no corresponding number for the narrowbody. The numerologists will get their fun when NSA gets closer to reality.
Nomadd wrote:Has there been a decision on the hull? I remember a Boeing engineer saying that a CFRP hull like the 787's wouldn't have any weight advantage over aluminum for a 737 size craft because the thickness wouldn't scale down.
Triumph Aerospace Structures vice-president of engineering Martin Perya thinks it would be "extremely difficult, if not impossible" to adopt a composite airframe for a single-aisle aircraft with today's carbonfibre technology. He says "high level" investment would be required to scale up production capacity with facilities featuring autoclaves, clean rooms and cold storage spaces, and that such infrastructure is "largely impractical for higher-volume production".
Perry notes that autoclave processing is "the single most cycle-time-affecting process in the value chain". He adds: "The economic viability [of potential capacity expansion] is very wearisome as the investment required would be significant and return on that investment is somewhat risky." He believes a "different approach" is needed as "there is a kind of limit that I think the industry is... hitting right now with that thermoset technology".
As Boeing evaluates options for its proposed New Mid-market Airplane (NMA), it is arguably under greater pressure than rival Airbus to decide whether to adopt a composite design for an all-new aircraft. Marketing vice-president Randy Tinseth said in March that the airframer would use on the NMA "proven and understood" technologies rather than radical new ones, and that the manufacturer plans "no big technology push as we saw on [the] 787".
TWA772LR wrote:I remember the 787 was originally launched as the 7E7. Considering the Mom moniker, does that mean the 797 will be launched as the 7M7?
Stitch wrote:TWA772LR wrote:I remember the 787 was originally launched as the 7E7. Considering the Mom moniker, does that mean the 797 will be launched as the 7M7?
The "E" stood for "Efficiency" to reflect the significant fuel efficiency improvements compared to earlier Boeing models (i.e. - 767).
TWA772LR wrote:I remember the 787 was originally launched as the 7E7. Considering the Mom moniker, does that mean the 797 will be launched as the 7M7?
Revelation wrote:Nomadd wrote:Has there been a decision on the hull? I remember a Boeing engineer saying that a CFRP hull like the 787's wouldn't have any weight advantage over aluminum for a 737 size craft because the thickness wouldn't scale down.
There's a very interesting article on this very subject at FG ( https://www.flightglobal.com/news/artic ... ro-449415/ ).
One quote:Triumph Aerospace Structures vice-president of engineering Martin Perya thinks it would be "extremely difficult, if not impossible" to adopt a composite airframe for a single-aisle aircraft with today's carbonfibre technology. He says "high level" investment would be required to scale up production capacity with facilities featuring autoclaves, clean rooms and cold storage spaces, and that such infrastructure is "largely impractical for higher-volume production".
Perry notes that autoclave processing is "the single most cycle-time-affecting process in the value chain". He adds: "The economic viability [of potential capacity expansion] is very wearisome as the investment required would be significant and return on that investment is somewhat risky." He believes a "different approach" is needed as "there is a kind of limit that I think the industry is... hitting right now with that thermoset technology".
So this is about single-aisle but it could apply to 797 given the production volumes they want to hit.
And in the context of 797:As Boeing evaluates options for its proposed New Mid-market Airplane (NMA), it is arguably under greater pressure than rival Airbus to decide whether to adopt a composite design for an all-new aircraft. Marketing vice-president Randy Tinseth said in March that the airframer would use on the NMA "proven and understood" technologies rather than radical new ones, and that the manufacturer plans "no big technology push as we saw on [the] 787".
It'll be an interesting choice.
You should read the article because it has lots of other interesting quotes in it, but I'll say it ends by pointing out that metallics are also making advances all the time so composites not only have to catch up in terms of production cost and flexibility, they're also chasing a moving target.
Beyond this, Boeing has not telegraphed their decision on the fuse yet. I can imagine the decision could go either way.
Keep in mind the beloved Airbus A220 has composite wings and metallic fuselage and no one is making a big thing about that.
TWA772LR wrote:I remember the 787 was originally launched as the 7E7. Considering the Mom moniker, does that mean the 797 will be launched as the 7M7?
dvincent wrote:The 767 was the 7X7, the 757 was the 7N7...
dvincent wrote:I don't recall what the 777's was, but it was an outgrowth of the 767-X project.
monomojo wrote:Revelation wrote:Triumph Aerospace Structures vice-president of engineering Martin Perya thinks it would be "extremely difficult, if not impossible" to adopt a composite airframe for a single-aisle aircraft with today's carbonfibre technology. He says "high level" investment would be required to scale up production capacity with facilities featuring autoclaves, clean rooms and cold storage spaces, and that such infrastructure is "largely impractical for higher-volume production".
Perry notes that autoclave processing is "the single most cycle-time-affecting process in the value chain". He adds: "The economic viability [of potential capacity expansion] is very wearisome as the investment required would be significant and return on that investment is somewhat risky." He believes a "different approach" is needed as "there is a kind of limit that I think the industry is... hitting right now with that thermoset technology".
Hasn't Boeing (among others) been working on out-of-autoclave cured composite structures for exactly this reason, to remove the autoclave processing bottleneck in production?
JayinKitsap wrote:CFRP barrels have the potential for high automation with relatively low amount of custom jigging, basically the mandrels (yes very fancy collapsing ones). Look at pictures of the 787 barrel construction vs the Spirit line link that I am Lucky posted. The barrel riveters in that photo can only do the 737 geometry. All of that equipment has locked in the diameter of the current tubes, but the 787 layup robots could the 797 layup as well, but on the different mandrel.
The Triumph VP is correct on the current state, but it seems to be working for the 787, should work similarly on the 797 as the technology on how to manufacture matures. Having the future NSA being the 3rd CFRP barrel method provides 2 more opportunities to tune the process.
JayinKitsap wrote:CFRP barrels have the potential for high automation with relatively low amount of custom jigging, basically the mandrels (yes very fancy collapsing ones). Look at pictures of the 787 barrel construction vs the Spirit line link that I am Lucky posted. The barrel riveters in that photo can only do the 737 geometry. All of that equipment has locked in the diameter of the current tubes, but the 787 layup robots could the 797 layup as well, but on the different mandrel.
The Triumph VP is correct on the current state, but it seems to be working for the 787, should work similarly on the 797 as the technology on how to manufacture matures. Having the future NSA being the 3rd CFRP barrel method provides 2 more opportunities to tune the process.
monomojo wrote:Hasn't Boeing (among others) been working on out-of-autoclave cured composite structures for exactly this reason, to remove the autoclave processing bottleneck in production?
GKN Aerospace, through its Dutch aerostructures division formerly known as Fokker Technologies, supplies thermoplastic leading-edge parts for the A380 and control surfaces for Gulfstream G650 business jets. Russ Dunn, GKN's senior vice-president for engineering, technology and quality, says thermoplastics have traditionally been used for lighter-loaded structures, while thermosets are suitable for large, complex primary structures, as they can be optimised for high static strength.
However, GKN is exploring the use of thermoplastics for "major structural components" – including fuselage skins, empennages and wing components – and is making "very good progress", says Dunn.
Perya describes thermoplastics as "almost the holy grail" of aerospace materials. Looking back at how employment of thermosets has grown over past decades, he expresses surprise that the aerospace industry did not concentrate earlier on opportunities offered by thermoplastics. He thinks the manufacturers were slow to adopt the material after they had spent time and effort on development of thermoset composites.
trpmb6 wrote:Honestly autoclaves aren't really the problem. If you do an out of clave cure you still need ovens. Ironically there have been situations where (undisclosed supplier) has been curing things that are meant for out of clave cure inside autoclaves because they didn't have the oven capacity.
trpmb6 wrote:The problem is the nature of composite properties. You really only need a couple plies to take the pr/t strains of a fuselage at altitude. The problem is all the accidental damage and other problems like hail strike. There is a crossover point for the crown skins where at certain radiuses and frame/stringer spacings it's more weight efficient to go with aluminum than it is to use composites. Hail impact is just that severe and aluminum responds better to that kind of impact than composites do.
Miguel Castillo Acero, vice-president of technology development at Spanish aerostructures specialist Aernnova, estimates that the costs of producing composite aerostructures are 40-100% higher than for comparable metal components, depending on part complexity.