Federal Aviation Administration today ordered airlines to stop flying their Boeing Dreamliner jets until they can show they'have fixed a fire risk linked to battery failures aboard the jets. The move follows an emergency landing in Japan that prompted that country's two major airlines to ground their fleets of 787s, and a similar problem aboard a Dreamliner on the ground in Boston nine days earlier. "The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787 airplanes," the FAA announced this evening. "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."