SOME OF THE ICE PATROL'S PROBLEMS, AND HOW IT 



ATTACKS THEM 



The primary duty of the ice patrol is locating and broadcasting the 

 position of all ice near the steamship tracks which cross the North 

 Atlantic south of Newfoundland. The patrol service is maintained 

 to assure, if possible, that vessels using these tracks will not run 

 unwarned into ice-infested waters. 



The patrol's responsibility is certainly not the safe passage of }?er- 

 sons, vessels, and freight across the ice-patrol regions. That is, 

 indeed, the final aim of the ice patrol's work, but the safety of each 

 individual ship is something not under the control of the ice-patrol 

 officials. Safety from dangers incident to collision with ice is de- 

 pendent upon the judgment of the individual shipmasters in estimat- 

 ing the situation ahead of them. The patrol's broadcasts give these 

 men a certain amount of late information, which is undoubtedly 

 useful as a guide for shaping their course and speed policies past the 

 Grand Banks. 



One patrol vessel is out on duty at all times during the heavy ice 



^season. The fuel capacity and other limitations of the vessels that. 



have been used to date are such that they can cruise at about 10 knots 



'during daylight hours of good visibility during their 15-day duty 



periods in the ice regions, and ordinarily no more. Greater work than 



:that they can not do because of the need for fuel to carry the ships to 



and from the ice area, to evaporate sea water for domestic and boiler 



purposes, to supply demands for steam during long stand-by periods 



•of fog, darkness, and storm, to retain position in currents, and for 



.emergency reserves. 



Bad visibility and bad weather together are so prevalent that on the 

 ■average the patrol can count on no more than 150 hours of efficient 

 ■searching weather per 15-day period of patrol duty. During these 

 150 hours the patrol ship averaging 10 knots can run 1,500 sea miles 

 and can sight bergs at an average distance of not over 15 miles on 

 either hand. In other words, the patrol vessel herself can examine 

 not over 45,000 square sea miles of water area per average patrol 

 •cruise, even when every available hour of good visibility is utilized to 

 .the full for search purposes. 



Some ground is lost because of doubly searched areas that unavoid- 

 ably exist about the corners of the search patterns. Other reasons, 

 such as necessary overlapping of searches made on different days due 



(83) 



