Everything I've seen in Aviation Week and elsewhere says twin-aisle. The fuselage weight penalty for an extra aisle is not that much, and considering that the fuselage is widely reported to be elliptical I'd say the penalty is almost nil (because the fuselage itself will generate lift). Also, Boeing is putting folding wingtips on the 777x, I'm betting the same for the 797.

My bet is a widebody with a fuselage no longer than a 900ER and folded wingspan no greater than a 900ER. So, we get a twin aisle aircraft that fits inside a standard narrowbody gate with efficiency that at least matches a -10 Max and probably exceeds it significantly. Would be wonderful on our most congested routes and into our most congested hubs. Winner.

We're gonna need a bigger boat... I mean, passenger waiting areas.

 

I think that it'll be a new concept. The XWNB (extra wide narrow body) 2x2x2 seating for coach, 2x1x2 first. I think that it should be between the hull diameter of a 737 and 767. Maybe be able to accept containers in the bellies.

 

Serious question: aren't the 787 and 767 roughly similar in pax capacity? They're very similar in external dimensions. The greater range comes from engine/aero efficiencies an higher cruise altitudes (I've ridden on them several times in the 400-410 range).

That's why I thought it would go narrow...the 787-8 is already kind of a 767 Equivalent.

Gotta admit: Lazurus' idea of a guppy-sized span/length, but two-aisle in the 160-190 seat range is interesting.

I think regardless, as Dash mentioned, containers are a must for loading expediency.

 

the 787-8 is exactly the same size as the 767-300ER. It just flies to dang far. For that reason it carries to much extra weight. Put in a smaller center tank and up the max ZFW. This should add more cargo room.

The mission we need is sub 12hrs. 150,000ish pounds of fuel should suffice.

 

So the 767-200 would have been perfect for what UAL is looking for.

 

Not a real efficient airplane for 2020

 

And I gotta admit, container/cargo capacity is the second biggest question mark in my mind. I don't know how Boeing would manage to fit in standard cargo containers. A custom design might be required and wouldn't be unprecedented. One thing is that I don't see 797s flying routes with a lot of bulk cargo demand - rather Hub to Hub or TATL from EWR/IAD/ORD to smaller European cities such as EDI. So, less cargo capacity than a 787/777 might not be a major issue.

Biggest question in my mind is engine placement. A lot of advanced concepts these days have them above-wing near the trailing edge, as there are quite significant weight and balance benefits. While we might like looking at the engines under the wing ourselves on the walkaround right now, I think future engine generations will be able to detect and automatically report problems well before we ever could spot them. And hopefully they won't need oil top offs on a regular basis either...

 

Boeing has "shrunk" airplanes in the past, after initially "growing" them. Examples: 707-120, -320, and then the shorter-range B-720. 747-100, 200, then the 747SP (long range, but fewer pax, at 47 ft shorter!), and a short-range, high density version for JAL's intra-Japan market (747SR? I forget).

Anyway, I agree wholly: it would seem a "787-7," with less fuel and more load, would be the 767 equivalent.

Asking here because I've not loaded bags: isn't it faster to load baggage in containers than one at a time? Wouldn't it also be faster to take a bag off (pax misconnect) if they knew what pod it was in?

For that reason, plus freight (if any), I figured the 797 would have pods.

I still figure the 797 will be paired with the 787 for type-ratings. And that will have a synergistic effect.

 

It's not a new concept. Remember the 767-200 "Dump Truck"?

 

https://www.flightglobal.com/news/ar...irplan-438512/
Boeing partially unveiled a New Midsize Airplane (NMA) concept with a 787-like composite wing and fuselage, a likely narrower wingspan than the Dreamliner and, for the first time, what the company calls a "hybrid cross-section".

After achieving an authority-to-offer decision earlier this year, Boeing is still perhaps months or a year away from a launch decision for an aircraft sized to carry 200-270 passengers and fly 5,000nm.

But more details of the concept have been released at the Paris air show, as the early configuration of the NMA takes shape within Boeing, which is in discussions with a host of potential suppliers, including engine companies.

The NMA will use composites "extensively" in the wings and fuselage, says Mike Delaney, Boeing's vice-president and general manager of aircraft development.

Structural materials could include advanced applications, among them out-of-autoclave thermoset composites and thermoplastic composites.

Another challenge will be identifying engine suppliers. Boeing is in discussions with GE Aviation, Pratt & Whitney and Rolls-Royce to define the NMA's clean-sheet propulsion system, which has been described as 40,000-50,000lb-thrust.

The new aircraft invites the opportunity to push the boundaries of technology, including bypass ratio. Asked in an interview if bypass ratios significantly above the current standard of 10:1 were possible for the NMA, Delaney confirmed they were.

That suggests a requirement for a power gearbox to decouple the rotation speeds of the low-pressure turbine and the fan blades, to prevent the latter from spinning above Mach 1.0. Without elaborating, Delaney says the engine companies have more options than using a power gearbox.

"We don't tell the engine guys how to design their architecture," Delaney says.

Perhaps the most intriguing design aspect of the NMA is the fuselage geometry. Boeing's early design studies have focused on optimising the cross-section to accommodate passengers, at the expense of creating space below-deck to carry bulk cargo pallets or containers.

The result is a hybrid cross-section for the fuselage, blending the passenger comfort of a twin-aisle on the main deck and the cargo compartment of a single-aisle below deck.

"It is a geometry that enables single aisle economics and twin-aisle comfort," says Delaney.

Using such a configuration, Boeing thinks the NMA will drive a new paradigm for operating economics in aircraft sized to fly 3,000-5,000nm. Delaney points to the precedent set by the 787. Boeing designed that aircraft to match the seat-mile cost of the 777 at significantly lower trip-cost.

"We want to do the same thing now into the market below the '87," Delaney says.