Boeing's Dreamliner

Watched by hundreds of cheering workers from the aircraft factory, Boeing’s 787 Dreamliner took to the skies for the first time at an airfield near Seattle, in a long-delayed test flight for a plane viewed as a breakthrough due to its lightweight design, hi-tech composition and fuel efficiency.

At 10.30am local time, the plane, painted in blue and white Boeing livery, lifted off smoothly in damp conditions. But the flight, which was due to last four hours, was brought to an end an hour early when persistent rain swept through the area. Flown by Boeing's chief test pilot, Mike Carriker, the 787 was flanked by two T-33 military reconnaissance aircraft and was filled with equipment to measure its performance, efficiency and safety.

In a rare show of solidarity, Boeing's European rival, Airbus, paid tribute to the US company and promised robust competition: "Airbus congratulates the people of Boeing on this important achievement in their history."

About half of the 787 is built from carbon and titanium composites, rather than the aluminium used for the majority of commercial airliners. Its lightweight design has allowed Boeing to promise tens of millions of pounds of savings on fuel and maintenance to its customers. Boeing has received orders for 840 aircraft, including advance sales to British Airways, Virgin Atlantic and Monarch Airlines, and the plane is viewed as crucial to Boeing's success in its commercial rivalry with Europe's Airbus.

"It's only the second time in the history of aviation that the materials with which aircraft are built have fundamentally changed," said Wolfgang Demisch, a New York-based consultant on aerospace finance. "They went from wood and fabric to metal. And now from metal to composites."

Conceived in 2003, the 787's journey to its first flight has been a turbulent one. The test was two-and-a-half years late after a series of technical hold-ups, strikes and problems with suppliers. At one stage in the highly delicate process of assembly, progress was hampered by a tiny disparity of 0.3 inches at the connection between the plane's cockpit and fuselage sections. More recently, engineers have struggled with a shortage of bolts and with a stress tests on a joint between the wing and the body.

A mid-size plane, the 787 will carry about 250 people on long-haul routes of up to 8,200 nautical miles – covering London to Jakarta in one hop. It will use 20% less fuel than more conventional aircraft.

The Dreamliner faces a further 10 months of tests to obtain full certification of its air worthiness before deliveries to airlines can begin. If all goes to plan, the first deliveries could take place at the end of 2010.