A cable strumming experiment (the Bermuda Testspan) was conducted by the U.S. Navy from 

 December 1973 to February 1974. The site of the experiment was near Argus Island, Bermuda. A 256 

 m (840 ft) long, 16 mm (0.63 in.) diameter electromechanical cable was suspended horizontally in the 

 water at a depth of 28 m (92 ft). The cable had no strumming suppression devices attached, but it had 

 numerous weights, instrumentation devices, and floats distributed over its length. The experimental 

 arrangement is shown in Fig. 3.21. The unfaired cable and instrumentation were similar to the cables 

 which made up the horizontal delta module of the SEACON II array. Two current meters were 

 suspended near the mid-span point of the cable. 



Kennedy and Vandiver (55) have analyzed the results of this experiment and have reached 

 several conclusions. They found that the strumming response of the cable was typical of a broadband 

 random process and that resonant and nonresonant lock-on were rare. The high modal density, which 

 ranged from the 10th to the 150th mode, and extreme variations in current speed and direction were 

 chiefly responsible for the broadband response of the test span. The peak rms cross flow displacement 

 amplitude experienced by the Bermuda Testspan was estimated by Kennedy and Vandiver to be y = ± 

 0.5 D. A more thorough discussion of this large scale field experiment is given by Kennedy (60). 



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