The Russian International Aviation Committee has released information from the flight recorders of the crashed plane that killed 71 people. Experts have started studying the two devices, as well as some of the 500 plane fragments recovered so far. Investigators have opened a criminal case into the tragedy. They said in a statement that the plane was not on fire and was in one piece when it plummeted to the ground. Authorities have released the conversation between the pilot and aircraft dispatcher before the crash. It shows that the pilot may have found some problems before take-off.