AIRLINES expressed confidence in the safety of Boeing's 787 Dreamliner yesterday as investigators searched for the cause of a fire on one of the advanced jets and billions were wiped off the company's market value.

British officials said initial checks into what they called a serious incident appeared to rule out any link to the battery-related problems that grounded the Dreamliner fleet for three months earlier this year.

The fire on the Ethiopian Airlines plane at Heathrow Airport in London on Friday raised new questions about an aircraft seen as crucial to Boeing's future.

The incident was a setback for a company trying to rebuild confidence in its flagship jet and compete with Airbus in the booming market for more fuel-efficient long-distance planes.

Boeing shares fell 4.7 percent at US$101.87 on Friday after the Heathrow fire, knocking US$3.8 billion off the company's market capitalization.

In the early stages of the investigation, airlines said they would continue to fly their Dreamliners, while others confirmed they would stick to their plans to buy the aircraft.

Virgin Atlantic said it remained committed to taking delivery of 16 of the planes from the autumn of 2014. Delta Air Lines is buying a 49 percent stake in the airline.

Polish flag carrier LOT, the first European airline to take delivery of the 787 last year, said it was in constant contact with Boeing.