and Sst(f) is the average of the two leeward gauges (transmitted 

 waves) and Ssi(f) is the average of the two seaward gauges (incident 

 waves). It should be noted that values of Ct foi" any given frequency 

 are independent of the correction factor N(f). Figure 7 shows 

 transmission results for S^-(f)/S^-(f ) > 0.10 and f < 0.67 Hz 

 and the corresponding second-order regression curve. There is good data 

 coverage for 0.2 <^ L/B <^ 0.8. This range has been extended in Figure 8 

 by plotting results for the two values of frequency (at 0.04 — Hz 

 intervals) for each record that are just smaller than the smallest 

 frequency meeting the criterion S-i(f)/S^-(fp) > 0.10. The 

 corresponding second -order regression curve is also shown. This 

 provides good data coverage for 0.8 £ L/B <^ 1.4. 



The data plotted in Figures 7 and 8 is from 118 records 

 obtained between October 8 and November 13, 1982. Characteristic wave 

 heights vary from 12 to 66 cm with peak frequencies from 0.32 Hz to 

 0.64 Hz. 



The data in Figures 7 and 8 has been combined in Figure 9. 

 The curve through the data is the curve from Figure 7 for 0.2 <^ L/B < 

 0.6, from Figure 8 for 1.0 £ L/B <_ 2.2, and a transition by eye for 0.6 

 <_ L/B <_ 1.0. 



Some of the scatter in results is probably due to variability 

 in the direction of the incident waves. Under oblique attack, the 

 effective beam of the FTB is increased but this has not been taken into 

 account. A constant value of B = 18.9 m was used to determine values of 

 L/B. 



77 



