TAUT-WIRE MOORING FOR OPEN OCEAN ANCHORING.

Twenty taut-wire moorings were designed and placed to hold instrument buoys for the deep underwater detonation, Shot Wahoo, of Operation HARDTACK, Water depths varied from 300 to 1000 fathoms and the majority of the moorings enjoyed no protection of the nearby atoll from open sea conditions. These conditions consisted of a 12 to 18-knot breeze and a short 3-ft chop from the northeast superimposed over a 300-ft long, 6 to 8-ft high swell from the east southeast. Of the twenty moorings place, 7 or 8 survived the effects of the event. One failed from collision with a vessel. Eleven failures resulted from undetermined effects of the detonation. The cause for ten of these was a tension break at the lower end of the cable the cause for the eleventh could not be determined. The remaining mooring, which had no instrument buoy attached and was marked only by a spare subsurface buoy at the end of the nylon pennant, was never found. All but one cable failure was within 8000 ft of surface zero. However the survival of two moorings at 4800 ft from surface zero indicates that the wire size chose, though marginal, would have been satisfactory for open sea conditions alone. For the combined sea and detonation conditions that did prevail, an increase to 14-in. diameter cable for stations within 8000 ft of surface zero probably would have been sufficient to maintain all moorings. Author