The seats and aisles are wider

The Japanese airline has ordered 50 of the mid-sized planes worth up to $6bn.

The Dreamliner with bigger windows and wider aisles and seats is designed to use 20% less fuel per passenger.

The aircraft - Boeing's first entirely new model in a decade - is seen as a bid to regain market share from Airbus which overtook it last year.

Spying scandal

Airbus is pushing its double-decked A380 which can seat about 555 passengers - around 155 more than current jumbos - as a means of allowing airlines to service the busiest routes.

DREAMLINER 7E7 Uses 20% less fuel More cargo space Higher humidity Wider seats and aisles Larger windows 200-300 seats Can travel 6,500-16,000km

But Boeing is hoping airlines opt for its lighter more fuel-efficient jets to get customers to their destinations more directly.

The Dreamliner which will eventually replace the 757 and 767 will start flying from 2008.

Boeing has been rocked by a series of scandals which led to the resignation of the company's chief executive Phil Condit at the end of last year.

The scandal surrounded lucrative US air force contracts and allegations that they were illegally acquired using insider information from arch-rival Lockheed Martin.

In 2003, Boeing delivered fewer jets for the first time ever than its European rival Airbus.