Yet another fleet of Boeing airplanes was found to have a potentially disastrous flaw — one that could set the entire aircraft ablaze.The Federal Aviation Administration found that the company’s 777 liner has poor electrical insulation near its fuel tank, according to a proposed rule the federal regulator posted in March.“This condition, if not addressed, could result in an ignition source inside the fuel tank and subsequent fire or explosion,” the Airworthiness Directives note states.The fuel tanks of near ...