electronic load cell for the southwest corner mooring line was installed 

 but did not work. 



Wind velocity data was obtained from a cup anemometer and vane 

 installed on a tower on La Salle Park Wharf (Figure 4) at an elevation 

 of 10 m above mean water. The anemometer was calibrated in NWRI's 

 towing tank for speeds up to 6 m/s. The difference between pre- and 

 post-season calibrations was -2.6 percent. The post-season value was 

 used. The compass was calibrated on the tower with readings taken by 

 pointing the vane at known reference locations around the harbour. 

 Bearings were then determined accurately from a map. 



The pressure, load and wind sensors were connected to a 

 12-channel Sea Data logger via a custom built control unit (Valdmanis 

 and Savile 1984). The control unit activated the logger whenever the 

 wind speed and direction met pre- set conditions. This limited recording 

 observations to significant events. A nine-minute sample of data would 

 be collected at 2 Hz, followed by a 51-minute gap. At the beginning of 

 the next hour, the control unit would check the wind conditions to 

 determine whether to start collecting another sample. 



In order to improve the resolution of the data gathering 

 system, a duplicate set of the pressure signals with the means removed 

 was amplified 21.8 times and stored along with the other data on 

 cassettes by the Sea Data logger (Valdmanis and Savile 1984). 



72 



