Boeing Y3 Composite 370-500 Seat Twin VLA Design "Ecoliner"
Last week I posted this topic on another forum, just thought Í should share.
Henry Lam ( http://www.kaktusdigital.com) found some time to create an exterior some artist impressions.
The 350-500 seat market segment
Looking at aircraft currently available there seems to be a market for larger aircraft. New VLA´s are launched by the bigger OEMS (747-8i and A380) and there is pressure to enlarge aircraft types seating over 300 passengers (A350XWB, Boeing 777 and Boeing 787. The 747-8i falls in the middle off this. Sales could indicate there might be room for a new passenger aircraft in say 10 years, the A380 seems too large for many airlines and markets.
Existing technology offers opportunities for very efficient design
New materials such as composites for fuselages and structures, large efficient turbofans such as Trent and GENX ovffer technology to make a significant step in efficiency in the 350-480 seat segment. Full length double deck offers gains in structural efficiently at limited fuselage lengths.
A solution could be a cross section offering 777 like maindeck flexibility: 9-10 abreast and a full length upperdeck significantly smaller then the A380, but far more practical then the limited 747 upperdeck.
Larger: http://www.kaktusdigital.com/images/large/y3_i01.jpg
Adding cabin length & width to rise capacity
Both sides of the Atlantic have been studying cabin configurations. Stretching length above 80m creates airport restrictions that are probably prohibitive for many airlines. Likely no passenger aircraft will longer then 777-300ER, A340-600 or A380-900 in foreseeable future. Adding width creates problems of it’s own in terms of evacuation, efficient use of space. It becomes very large and heavy.
Twin engine widebodies
Since Airbus introduced widebody twin in the seventies, scale of both turbofans and airframes have grown. There seems to be no real limit but Equipping 500 passengers with 2 engines above the Pacific, poles and Siberia might prove undesirable for many airlines, passengers and authorities.
A compromise could be to fit such an aircraft with 2 large engines and an APTU (Auxiliary Power and Thrust Unit) providing thrust during critical flight stages. Boeing studied it during the nineties. A twin + APTU seems to offer significant saving over a conventional four engined configuration.
A full composite twin VLA facilitating between 370 and 500 passengers (shorter + longer version) could have specification very competitive to current available aircraft types.
I think in the next decade there will occur a gab in the VLA market under the A380. A big twin+ seems a feasible alternative / 747 replacement for many airlines. What do you think?