Flywheels are typically made of steel and rotate on conventional bearings; these are generally limited to a revolution rate of a few thousand RPM. Some modern flywheels are made of carbon fiber materials and employ magnetic bearings, enabling them to revolve at speeds up to 60,000 RPM (1 kHz). Carbon-composite flywheel batteries have recently been manufactured and are proving to be viable in real-world tests on mainstream cars.
1925: The Tri-State Tornado. Indiana was one of three Midwest states in the path of the deadliest tornado in American history. On March 18, 1925, the Tri-State Tornado traveled a record 219 miles on the ground from Missouri through Illinois and into Indiana, where it struck Posey, Gibson and Pike counties.
More about the power of tornadoes: 1  Tornado Alley encompasses the eastern section of South Dakota, eastern Colorado, Nebraska, Kansas, Oklahoma and northern Texas. 2  One of the deadliest tornadoes in recorded history was the Tri-State Tornado of 18 March 1925. The tornado traveled a total of 219 miles, killing 695 people in Illinois, Missouri and Indiana. Although Oklahoma City holds the record for the most tornadoes, tiny Codell, Kansas, holds the distinction of being struck on the same date for three consecutive years, with tornadoes occurring on 20 May of 1916, 1917 and 1918.