Abstract: A skyline log-yarding carriage has three drums including an in-haul drum, a haul-back drum, and a drop line drum, all interconnected for rotation in the same direction at the same time. The carriage also has a drum brake and a cable clamp, the latter for holding the carriage stationary on the skyline. The brake and clamp are applied alternately by remote control. The in-haul and haul-back drums are positioned at opposite ends of the carriage above the level of the drop-line drum. However, the haul-back drum is located slightly below the level of the in-haul drum so that a slack-pull line can pass from the underside of the haul-back drum forwardly from the carriage to a powered yarder drum in a cable passage thus created between the in-haul and drop-line drums for gravity or "shotgun" yarding. In gravity yarding the slack-pull line is used to lower the drop-line under power for attachment to a load while the brake is released and the clamp applied.

Abstract: A cable clamp includes a box-like housing with opposite sidewalls, an open top and opposite end openings. A clamping mechanism within the housing includes a pair of laterally and longitudinally movable, laterally spaced inner clamping blocks with replaceable wear plates on their inner faces defining a cable passage therebetween so that a cable can pass freely longitudinally through the housing. A pair of outer wedging blocks back up the inner blocks and are laterally but not longitudinally movable within the housing. The outer blocks are spaced inwardly from the sidewalls of the housing to define wedging spaces. Longitudinally double-tapered outer faces of the inner blocks mate with complementary inner faces of the outer blocks. The outer faces of the outer blocks are vertically tapered to receive correspondingly tapered wedging surfaces of activating wedges movable vertically within the wedging spaces to drive the outer and inner blocks laterally toward the cable, causing the wear plates to grip it.