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.
The American Red Cross and other volunteer agencies will arrive with food and water, and temporary housing will be designated by FEMA. 1  Reflectivity of the supercell that produced the Moore, Oklahoma tornado on May 3, 1999. At the time of this radar scan, a tornado was on the ground.