Most core rigs over 15 feet (5 m) in length are cumbersome, awkward, and in bad weather somewhat dangerous to handle. On all Woods Hole Oceanographic Institution ships, coring is done over the side, using a hydraulically operated A-frame. In recent years, two methods have been used to transfer the core rig from its point of assembly to its 'down' position outboard, attached to the lowering cable....
Burke, John C.. 1968. "Davit for handling piston corers." Journal of Marine Research 26, (2). https://elischolar.library.yale.edu/journal_of_marine_research/1125