A load lowering descent controller having a fixed cylindrical body or capstan about which a rope or cable is turned. The descent controller allows for lowering of the load at a controlled rate by adjusting the amount of friction between the controller and the rope or cable as a function of rope or cable turning and relative contact with rope or cable engagement surfaces in the controller. The fixed cylindrical body or capstan is surrounded by a vented sleeve to prevent the rope from becoming heated and to prevent the user from being injured.