Airbus now expects the plane to weigh in at 290 metric tons, instead of its earlier target weight of 276 metric tons. - about 5 percent heavier than the previous target. The additional weight is mainly a result of an 11 tonnes heavier fuselage as well as 2.74 tonnes of additional weight in its wings.

The A380 would weigh in at 1,153 pounds per passenger, compared with 913 pounds for a Boeing 747-400. The weight of an aircraft directly affects its fuel efficiency, a key performance measure for airlines deciding what planes to buy.

Airbus insisted that the A380 Airbus will still meet its fuel efficiency target 2.9 litres of fuel per passenger for each 100 kilometres of flying. (81 miles for one gallon of kerosene per passenger) when the plane goes into service in spring 2006.

Airbus says it could compensate for the A380's bulge by improving aerodynamic performance to maintain fuel efficiency.

Another option could be to squeeze more weight out of plane parts and furnishings such as passenger seats, galleys and toilets.