Abstract: The dynamic behavior of rotor systems with a cracked elastic support was analyzed.Experimental investigations of rotor vibration characteristics,in particular,caused by a crack in elastic supports by using the control of an active elastic support/dry friction damper,was carried out,It is proven that the damper is effective to reduce rotor vibration caused by cracked elastic supports.Experimental results show that the damper with the P control method,can be achieved with the emergency shutdown,and plays a key role of protecting rotor systems.