Hi newbiepilot, take a look and you should be able to see, left below, there are 2 aisles but 2 seats per row are removed for business class.
I think your idea for a new small airplane with a 30 inch aisle which expands cabin width by 10 inches is a bad idea since it does not increase seat count. I think a 35 or 52 inch wider cabin that allows 2x3x2 or 2x4x2 seating makes much more sense.
The way I view it, keesje's NSA design concept is all about trying to remove the drawbacks of having a large single aisle aircraft (boarding times, in-flight cabin challenges, business class seating etc.), while keeping the inherit benefits of a narrowbody (long and slim, low drag/weight). Additionally, but more importantly in my mind, his design concept addresses both development and production costs. The new NSA he is proposing is not only a MOM aircraft, but it is also the 737 replacement. High volume production equals lower costs, more aircraft sold. The benefits for the airlines, that can have aircraft of the same family doing both short and medium to long haul flights (flexibility, crew, ground facilities etc.), is major. I find keesje's ideas new and innovative. He is not just suggesting yet another 767 replacement with advanced materials.
Concerning cabin width, it is not only the number of Y seats abreast that is important, but also how efficient the cabin can take business class seats. Aisle access from all business class seats is extremely important. The suggested NSA cabin can have four business class seats abreast, all with direct aisle access. The NSA cabin width is very efficient is this regard. Concerning Y seats, 6 abreast Y seats and 10 inch wider aisle, compared to 7 abreast Y seats and two narrow aisles, is similar from a cabin width efficiency point of view. Just divide cabin width, with number of seats abreast. One can argue for one or the other, it all depends on how large the MOM should be. But remember, two aisles doesn't solve the trolleys blocking the aisle problem. A wide aisle does. Boarding a plane with a wide aisle, where people can pass each other, might be more efficient than two narrow aisles. When boarding a widebody, the FAs must check each passengers boarding pass in order to direct the passenger to the correct aisle.
Reading through all the posts in this tread, it is quite obvious to me that people's notions of what constitutes a MOM aircraft, are very different. For me a MOM aircraft is a plane that is optimized for medium to long haul flights, that's flights with a scheduled flight time roughly between 7 to 10 hours (+/-). Both the A339 and 787-10 is within this sweet spot, but these aircraft a way to large for many routes and airlines. The A321LR will probably be able to do 8 1/2 hours scheduled flight time, but is it an optimized design for these long flights?
Many of the posters here, in my opinion, are suggesting way to large aircraft for a MOM. What is actually lacking in both OEMs catalogs are small aircraft able to do longer haul. Direct point-to-point flying saves costs (flight time, therefore also fuel, navigational and landing fees, hub airport charges, taxes etc.). I also think passengers are willing to pay more for flying direct and thus saving time. The 787 promised to open up more direct flights, and has enabled that to some extent, but it became to large, to costly, and to capable (range).
How large is the 787-8? Most commonly it is configured with 220 to 240 seats in a 2/3 class layout (just take a look at seatguru). In an all Y configuration, with 9 abreast seating @ 31 pitch, the 787-8 can seat approximately 300 passengers. In an all Y, 6 abreast seating @ 31 pitch, the A321LR (in 2019) can seat up to 220 passengers. I think the initial MOM aircraft should be closer to the A321LR size, and later stretched and gradually made more capable (range). If you are in the camp that actually wants a 787 sized MOM, just shorter ranged, I would tell you that the benefits of an aircraft with a optimized design range of about 1000 nm less, is greatly overstated. It would be better to misuse a 787-8, instead of paying for a clean sheet design. Remember that the MOM must cost less to manufacture in order to have narrowbody economics.
The CEO of Norwegian said during a press conference that the A321LR would have a lower fuel burn than the 787 crossing from Western Europe to the US East coast. And then he added, "and we don't have to fill all those seats" (higher seats counts equals lower yields per seat, higher risks an challenges during low season, less fleet flexibility, and some routes can't support a large aircraft). Norwegian is a major 787 customer (43 on order is a remember correctly), and have 30 A321LR on order.
The point here I think is that the wider aisle does increase seat count, by allowing a much longer tube (thus more seats) which can still be boarded and disembarked in a short timespan ...
Whether that is better than a tight 2-3-2, with a stubbier body for the same capacity, is a moot point.
Might be worth having a look at the MC21, which has a cabin 6" wider than the A320, so is a fair way towards the concept Keejse is proposing already.
Excellent, I agree.
It depends how large the MOM should be, ref. stubbier body vs long/slim body. A some point a widebody would be better choice. The wider aisle makes it possible to have a larger narrowbody, and therefore moves this threshold.
Last edited by reidar76
on Sat Mar 11, 2017 9:29 am, edited 2 times in total.