. Deep-sea moorings; design and use with unmanned instrument stations. Deep-sea moorings; Oceanographic buoys. Isaacs-Faughn-Schick-Sargent: Deep-Sea Moorings 281 may be estimated from towing and wind-drag curves for the hull, and approxi- mately equals the way that the hull would make before the same wind. The orient- ing effect of this initial velocity at the approach of a comber is a very important factor and demands some wind drag in the design. As the next comber will start to break at the point where the preceding one terminated, it is necessary that the surface float return part way tow
. Deep-sea moorings; design and use with unmanned instrument stations. Deep-sea moorings; Oceanographic buoys. Isaacs-Faughn-Schick-Sargent: Deep-Sea Moorings 281 may be estimated from towing and wind-drag curves for the hull, and approxi- mately equals the way that the hull would make before the same wind. The orient- ing effect of this initial velocity at the approach of a comber is a very important factor and demands some wind drag in the design. As the next comber will start to break at the point where the preceding one terminated, it is necessary that the surface float return part way toward its orig- inal position before the next comber breaks. Otherwise it will be carried farther from its original position, putting additional stress on the system and risking dangerous disorientation. The criterion of safe performance is that the stressed system shall move the surface float approximately % of the distance it was dis- RADAR REFLECTOR STROBE OR STEADY LIGHT. -cr SKIFF DANGER ORANGE WHITE NUMERAL 500 FT PENNANT WITH SMALL ORANGE FLOATS NEAR SKIFF Fig. 4. Deep-moored instrument skiff. placed by the first comber in the interval between the moment that the first comber breaks and the moment that the succeeding comber breaks. For safety, then, the surface float must move about % of a wave length in % of the wave period, or at an average velocity of %2 of the phase velocity. The elasticity of the pennant provides the larger part of the available restoring force. Thus a 10 per cent elongation of a half-inch nylon rope in new condition will provide a restoring force of 700 pounds, or 10 per cent of the ultimate strength. A 20 per cent elonga- tion would result in a restoring force of 2,000 pounds, which is undesirably large in most circumstances, and should be avoided by proper design. The maximum force available is the sum of the maximum wind drag and the additional force exerted on the pennant by a displacement of the surface float over a distance equal to about 25 pe
Size: 2111px × 1184px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookpublisherberkeleyuniversityofcaliforniapre
