US crash investigators looking into the Asiana accident have provided an unusual amount of information to the public. Is that heading off conspiracy theories or creating confusion?
US and Canadian regulators have been warning for years that the type of rail car involved in the fatal derailment and explosion in Quebec is far more prone to rupturing in accidents than other models available.
Investigators are interviewing the flight's pilots and crew to help determine the cause of the Asiana crash at San Francisco International Airport on Saturday. Here are several factors under scrutiny.