A compression chuck for variously conducting and braking a rope, wherein the compression chuck includes a first and second portions. The invention includes a first biasing mechanism which maintains the compression chuck first and second portions in a disengaged condition with the rope, wherein the rope is conducted freely in response to outside forces on the rope. Also included is an actuator, wherein the actuator is operable to overbear the first biasing mechanism to place the compression chuck in an engaged condition with the rope in response to a rope break, braking movement of the rope. The first and second compression chuck portions may be carried on opposing parallel plates that are biased apart until the actuator moves such plates together in response to a rope break. At least one of the plates may be fixed to a crane head, crane, or other structure proximate a moving rope, when installed.