The fastest rotational speed for a ring or disc-shaped object was achieved by scientists at Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA, on 9 December 1985. Using an air turbine, the Demo 1C flywheel was spun up to a tip speed of 1405 m/s (5,058 km/h 3142.9 mph), at which speed it failed due to the stress on the materials involved.