A Single-armed Manta-board as a New Diver-controlled Planing Board and Its Use for Underwater Surveys

Due to inadequacies of previous underwater towing techniques and the special needs of a recent underwater survey, a modified mania-board technique was developed. With this new technique, the diver holds on to the manta-board with one arm; consequently, the board is referred to as a single-armed manta-board (sam-board). The sam-board proved inexpensive and highly maneuverable, allowing the divers to freely collect samples or record information. Through some experimenting with the board and changing some of the variables, such as rope lengths, towing speeds, etc., a highly efficient towing method can be achieved. Preplanning and strict diving safety procedures must, however, be implemented to assure efficiency. This paper presents the materials, guidelines for board construction, equipment, and preplanning and diving safety procedures necessary for the sam-board towing operation.

Construction and Operation of a Two-place Diver's Sled

Fisheries gear researchers have employed scuba diver-operated sleds to evaluate towed fishing systems since the early 1950's. One of the earliest sled designs was a converted Stokes litter in which two divers sat tandem with the forward diver operating the diving controls (Sand, 1956). The litter was relatively easy to maneuver and provided a comfortable platform for observing operational fishing gear. However, the use of underwater photographic equipment to document gear performance was difficult due to the limited mobility of the observer-cameraman.