Tsaacs—Faughn-Schick—Sargent: Deep-Sea Moorings 283 
SHOCK CORD 
SENSING ELEMENTS 
INSTRUMENT WIRE 
(A) Position in slack weather. 
(B) Position in heavy weather. 
Fig. 5. Shock-cord mooring pennant. 
married to it at intervals in S-shaped loops, as in figure 5. An advantage of this 
latter system is that the terminations of the instrument line remain at approxi- 
mately constant depths as the scope increases. In this system a specially designed 
submerged float (see below) is necessary to permit recovery of the instrument 
line. The shock cord is designed to be under considerable tension when vertical, 
and to extend to maximum allowable tension at the limiting weather conditions. 
The design of the elastic pennant is much simpler than that of the floating 
pennant, as the restraint history with displacement is readily calculated. 
THE SUBMERGED FLOAT 
The submerged float must provide sufficient buoyancy to support the mooring 
wire and to result in adequate tension at the anchor. (Adequate tension is dis- 
eussed later.) Subsurface floats have usually consisted of spherical steel tanks 
with a diameter of approximately 3 feet, and a wall thickness of % inch or more 
(commercial butane tanks and cylindrical steel tanks have been used). In use, 
subsurface floats are normally pressurized to about the ambient pressure at their 
