There are aspects of the failure modes of fan discs vs. flywheels. Most fan discs fail due to a huge imbalance due to the loss of a blade. I have done many tests like this and will attest that a fan letting go is not a fun thing.
And Saturday evening, a large and extremely dangerous tornado was reported near Glenn Heights, TX, south of Dallas, according to the National Weather Service. According to the Dallas Office of Emergency Management, there was some damage in the Glenn Heights area, but no reports of damage in the city of Dallas.
Members of Missouri Task Force One search-and-rescue team gather a tornado-damaged Home Depot store Tuesday, May 24, 2011, in Joplin, Mo. A large tornado moved through much of the city Sunday, damaging a hospital and hundreds of homes and businesses.