The Airbus A320neo has had its maiden test flight.

The European planemaker is counting on the upgraded version of A320 to generate hundreds of billions in revenue over the coming two decades.

After extensive flight trials the passenger jet is due to enter service in just over one year’s time, competing with Boeing’s medium-haul 737.

Airbus said newly developed Pratt & Whitney engines and various design changes will make it 15 percent more fuel efficient than the current model.

It expects orders for the plane to top 3,500 by the end of this year.

Airbus also said it was confident in the performance of the new Pratt & Whitney engine.

An on-ground failure and fire on a similar engine halted testing of Bombardier’s CSeries in May and flight testing of that jetliner resumed earlier this month.

“Pratt & Whitney have been very transparent with us and given us all the detailed differences and we are satisfied and confident in the performance of the engine and aircraft,” Fernando Alonso, head of Airbus flight operations, said when asked about the differences between the two engines.

Demand forecast upped

This week Airbus raised its 20-year forecast for jet demand, citing growth in emerging markets, with China on the brink of becoming the world’s aviation powerhouse.

The planemaker said it saw strong demand for wide-body long-distance jets as airport constraints force airlines to upgrade from smaller planes on some routes, and said it might speed up production plans for A330neo and A350 jets.

Airbus sees total demand for 31,400 passenger and freighter aircraft between 2014 and 2033, an increase of seven percent from its previous rolling 20-year forecast. That would be equivalent to $4.6 trillion (3.6 trillion euros) of industry revenue at list prices.

During that time, the world’s in-service fleet will double, and China is poised to displace North America as the world’s largest domestic market within a decade, Airbus sales chief John Leahy said.