Forecast traffic growth coupled with increasing congestion problems on the ground and in the air will lead to a demand for a UHCA early next century.
With passenger traffic growth rate in the order of 5.4% worldwide, a need for some 800-900 aircraft of 600 seats and above can be expected. The average capacity split could be 39% for a version with 600 seats and 61% for an 800 seater. These calculations indicate a theoretical need for the respective size classes which could also be satisfied partially by existing and future derivatives of large size aircraft. According to Airbus Industrie same 250 UHCA type aircraft could realistically be delivered to airlines during the first decade of the next century.
An aircraft of that capacity will have to be limited to a geometry of about 80 m x 80 m otherwise serve airport limits could be expected.
With the 747 already firmly established us in the fleets of the major airlines the double decker ovoid cross section seems to be the preferred solution for the airlines. In order to carry 600 passengers by not exceeding the 80 m fuselage length a 9/6-abreast seating configuration on two decks would be sufficient.
The benefits of technology and size would lower the seat mile costs by 11% on a 3000 nm trip compared to the largest existing civil aircraft.
The lower fuel consumption per seat compared to all other commercial aircraft is a contribute towards environmental protection and energy conservation.
Due to its huge dimensions main problems will arise at airports (ground movements, gate compatibility, passenger handling and turn around times), and at production facilities.