The tagging arrays were deployed from the 

 CGC EVERGREEN during April and June of 

 1974. This was accomplished by casting off a 

 spherical float attached to one end of the line. 

 The line was then paid out as the vessel steamed 

 around the iceberg. The cutter closed on the float 

 heading into the wind and retrieved the spherical 

 float with a grapnel. The two ends of the line, 

 each having eye splices and thimbles, were joined 

 together with a shackle. The tethering ring of 

 the RDF spar buoy was attached to the shackle 

 and placed in the water. The iceberg, thus en- 

 circled, carried along its array as it drifted. 



During the first cruise (April/May 1974) the 

 iceberg tagging project was plagued with the 

 difficulty of locating suitable icebergs for tagging 

 (i.e., small enough size) in the survey area. 

 Later a storm carried away the arrays from the 

 icebergs that finally were tagged. This storm 

 lasted about two days with winds reaching 38 kts 



and the sea increased to 16 feet. All three tag- 

 ging arrays were carried away and only one was 

 recovered. The line on the recovered array was 

 broken in two places. One break occurred with 

 such force that the ends of the line, fibers were 

 fused; there was no evidence of chafing. The 

 other break appeared to be the result of chafing. 

 Because of this, little useful drift data were ob- 

 tained from the first cruise. 



The second cruise, using similar arrays, met 

 with greater success because of more favorable 

 weather. The CGC EVERGREEN was able to 

 track several icebergs in dense fog for nine days. 

 However, the tagging arrays slipped repeatedly 

 over or under the icebergs. This necessitated 

 early recovery of the equipment, which drifted 

 away from the berg although the line circle had 

 remained intact. This result was completely un- 

 expected and probably resulted from the iceberg 

 snagging tha line and rolling out of the loop. 



RADAR AND VISUAL 

 IDENTIFICATION 

 SPAR BUOY 



Figure A-l— ICEBERG TAGGING ARRAY DEPLOYED 

 DURING IIP 1974 



18 



