the towing mode. However, the effect of increasing load upon the 

 maximum speed is progressively reduced. This is to be expected since 

 the incremental increase in s\ibmerged surface area of the FTB with 

 increasing load is least near the FTB ' s maximum loading capacity, and 

 the drag force on an object moving through water depends upon the 

 exposed area, but not upon the weight of the object. 



The maneuverability of the UTB while towing the FTB was excellent, 

 and both the FTB and the UTB handled well during these tests. 



Turning Radius of the Flattop Boat 



The turning radius of the FTB was determined using the boat's own 

 engines and also by towing it astern with a UTB. In both cases, the 

 engines were run at idling speeds , and in both cases the turning radius 

 of the FTB was estimated to be about 30 feet. Idling speeds were 

 necessary to minimize the turning radius. 



Deployment and Retrieval of Boom from the Flattop Boat 



(i) Deployment: The time required to deploy 900 ft of boom from 



the FTB using a UTB was measured under the no wind and no wave condition, 



and with the boom stored fore and aft, and athwartship. The faking 



and stacking of the boom fore and aft and deployment of the boom from 



this position over the rollers at the bow were felt to be both 



cumbersome and more difficult to carry out when compared with the 



athwartship position of the boom on the deck. 



For deployment with the boom faked and stacked fore and aft , a 

 crew of six men was required: two men in the utility boat (one man at 

 the controls and the other watching the line from the samson post to 

 the towing attachment of the boom) , and four men on the FTB (one man 

 at the controls and three men assisting boom deployment) . The total 

 deployment time for the 900-ft mixed boom measured from first 

 connecting the line from the towing attachment to the post of the UTB 

 to the dropping of the boom' s free end in water was found to be 

 approximately 8.83 minutes. 



Since fore and aft faking and stacking of the boom is considered to 

 be more difficult for deployment than the athwartship faking and stacking, 

 the fore and aft faking is not recommended if the deployment is to be 

 carried out over the rollers of the FTB. However, deployment of boom 

 from the port side, if desired, should be easier if the boom is faked 

 and stacked fore and aft, as determined during earlier tests, reference 

 8. However, two problems are anticipated in deployment from the port 

 (or starboard) of the folding FTB. (1) If the inner and the outer 

 railings of the FTB on one side are removed just prior to deployment 

 and replaced immediately at the completion of deployment, then the 

 deployment time will have to include time required for removal and 



19 



