US regulator grounds Boeing 787 Dreamliner after another emergency landing

US regulators have asked the country's airlines to ground their Boeing 787 Dreamliners, flown by eight airlines worldwide, including Air India, until they can show they've fixed a fire risk linked to battery failures aboard.

The move by the Federal Aviation Administration (FAA) follows an emergency landing in Japan that prompted two of its major airlines to ground their fleets of 787s, and a similar problem aboard a Dreamliner on the ground in Boston nine days earlier.

FAA's emergency directive, issued Wednesday night, initially applies to United Airlines, the only American carrier using the new plane so far, with six 787s.

The grounding - an unusual action for a new plane - focuses on one of the more risky design choices made by Boeing, namely to make extensive use of lithium ion batteries aboard its airplanes for the first time.

The batteries are part of an electrical system that replaces many mechanical and hydraulic ones common in previous jets.

"The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787 airplanes," the FAA said.

Since July, the growing list of reported troubles aboard the planes include a fuel leak, an oil leak, two cracked engines, a damaged cockpit window and a battery problem. The FAA announced a safety review of the aircraft last week.

"The root cause of these failures is currently under investigation. These conditions, if not corrected, could result in damage to critical systems and structures, and the potential for fire in the electrical compartment," it said.

FAA on Wednesday also said it expected international regulators would take "parallel action". That would ground all 50 of the 787s delivered so far.

In line with the decision by the US regulator, state-run Air India has grounded all six of its Boeing 787 Dreamliners over safety concerns.

Air India, which had ordered 27 Boeing 787s, received its first Dreamliner last September after a wait of four years. The airline is expected to take delivery of seven more in 2013, five in 2014, six in 2015 and three in 2016.

Seven other airlines now fly the Dreamliner.

Japan Airlines and All Nippon Airways are two of the 787's biggest customers.

All Nippon Airways was especially proud of its 787 fleet. Its executives' business cards and the top of its website read "787" and "We fly 1st." ANA got the first Boeing delivered in late 2011, more than three years late. Other 787s have had problems with certain electrical panels and fuel leaks.

The other operators are Ethiopian Airlines, LAN Airlines of Chile, LOT of Poland, Qatar Airways and United Airlines of the United States. Orders for about 800 additional 787s are in the pipeline.

In a statement released Wednesday night, Boeing Chairman, President and CEO Jim McNerney said the company is confident that the planes are safe and is working with authorities to get them flying again.

With inputs from IANS