The Airbus A380 is set to make its maiden test flight in April

The twin-deck aircraft can carry about 555 people - more than the Boeing 747 jumbo built by Airbus' main competitor.

The ceremony was attended by European leaders including Tony Blair, Jacques Chirac and Gerhard Schroeder.

French President Jacques Chirac praised the A380 as the "crowning achievement of a human and industrial adventure", describing it as a "European success".

Sign of confidence

It is a symbol of economic strength and technical innovation Tony Blair Jumbo versus "superjumbo" The A380 timeline

French, British, German and Spanish leaders represented the Airbus consortium at the "reveal ceremony" in Toulouse.

British Prime Minister Tony Blair praised the "dedication" of all those involved in the project and said the A380 was a symbol of European cooperation at its best.

"This is the most exciting new aircraft in the world, a symbol of economic strength and technical innovation," he said.

"Above all, it is a symbol of confidence that we can compete and win in the global market."

Confident of success

The first test flight of the A380 will take place in April although Airbus is keeping the exact date under wraps.

It will enter service in 2006.

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Airbus - a joint venture between European Aeronautic Defence and Space Company (EADS) and BAE Systems - has secured 149 confirmed orders for the A380 from 14 customers, including 11 passenger airlines.

Airlines have taken options on a further 100 planes.

Airbus chief executive Noel Forgeard said he expected sales of the A380 to comfortably exceed 250, the number required for the huge aerospace project to break even.

He said Airbus hoped to sell more than 700 of the aircraft and was in talks about selling the plane to China.

"We'll sell a lot more than 250. We'll sell 700 or 750. You know it is a plane which will fly for 30 or 40 years," he told RTL Radio.

Big is best?

By building the plane - with development costing about $11bn (£6bn) - Airbus is banking on demand for large planes offering cheaper seats between the world's major cities, experts say.

We shall make a family photo; something like this will never happen again Noel Forgeard, Airbus chief executive Read more about the Airbus A380 launch ceremony

For consumers, it maps out the future of air travel, or at least the version touted by Airbus.

However, Airbus' main rival Boeing is focusing on smaller new aircraft able to fly direct to a wider number of destinations.

Boeing's rival 7E7 'Dreamliner' project, which will enter service in 2008, has already secured orders from Continental Airlines and Japan Airlines.

Airport changes

The world's busiest airports are having to change their terminal buildings to accommodate the A380.

A380 CUSTOMERS Lufthansa, Virgin Atlantic, Qantas and Malaysian Airlines are among 11 passenger airlines to have agreed to buy the A380. Emirates is its largest customer, ordering 45 while Singapore Airlines will take delivery first in 2006 Airbus' 14 customers, which also include freight and leasing companies, have committed to spend about $40bn on the plane

Heathrow is spending £450m on preparing itself for the arrival of the A380, which will arrive and depart from Terminal 3.

"The A380 is critical for us," Eryl Smith, Heathrow's director of business strategy, planning and development told the Press Association.

"It will change the face of Heathrow and the face of long haul travel."

Controversial subsidies

Without government assistance, the A380 would probably never have been built.

Billions of euros have been handed over in "launch aid loans" in recent years - under generous repayment terms - to assist Airbus's development of the A380.

Airbus has downplayed the cost of the project despite the fact it could run as much as 1.5bn euros over budget.

"That sounds quite a lot of money until you realise you are dealing with a programme which is about 11bn euros," commercial director John Leahy told the BBC.

JUMBO JET AND SUPER-JUMBO Seating: Typical 416 (max 524) Cruising speed: 0.855 Mach Flight range: 13,450km Seating: Typical 555 (max 840) Cruising speed: 0.85 Mach Flight range: 15,000km