wise, to sliipping across the Nortli Atlantic it was dropped from the 

 ice bulletin broadcast on the 23d of April. 



Shifts in the North Atlantic Track Agreement tracks were effected 

 as scheduled without any recommendations from Commander, Inter- 

 national Ice Patrol ; that is, shipping on track C shifted to track B 

 on 11 Ai^ril and that on track D shifted to track E on 11 April. It is 

 estimated that 23 bergs drifted south of 48° X. during this month. 

 Fourteen ice-observation flights were made in April. 



The Canadian Department of Transport started its regidar aerial 

 surveys of the St. Lawrence area on 1 April. Prior to this date it 

 had undertaken preliminary flights on the 11th, 14th, 21st and 29th 

 of March. Thereafter reports were furnished daily by the Canadian 

 Department of Transport to shipping. The limits of ice on the 5th 

 of April were from 1.5 miles off Cape Ray to 47°00' N., 58°40' W., 

 to 46°00' K, 58°00' W., to 45°00' N., 59°00' W., to 40 miles off Canso. 

 This was the extreme limit of ice and thereafter the limits receded 

 until by the 28th of April it was reported that routes to river and 

 gulf ports via Cabot Strait and Strait of Canso were clear for navi- 

 gation. Aerial surveys by the Canadian Department of Transport 

 were discontinued as of that date. 



MAY 



A flight was made on 1 ]May north along the coast of Labrador to 

 determine the potentialities for the rest of the season. "\Mien planning 

 the flight, course lines were laid out to approximate the 1,000-f athom 

 curve, but as the flight progressed it was evident that the flight plan 

 should be shifted 25 to 50 miles nearer the coast. It was apparent 

 from this flight that bergs were few in number and that pack ice was 

 closer to the beach than expected. Combining the results of recon- 

 naissance flights on 30 April, 1, 2, and 3 May, it was estimated that 

 there were only 248 bergs and 69 growlers between 47°10' N., and 

 58°25' X., and west of 50° "\Y. The great majority of these were 

 within 50 miles of the east coasts of Newfoundland and Labrador 

 and in positions where drift to the Grand Banks would be unlikely. 



During this month the general pattern for flights was to maintain 

 a check on the bergs already sighted every 2 to 3 days and then to 

 send a flight southward along the east slope of the Grand Banks 

 about once a week. The majority of the bergs coming south of 48° 

 N., during INIay were west of 51° AY., and either entered Conception 

 Bay or grounded along the east coast of the Avalon Peninsula be- 

 tween Cape St. Francis and Cape Race. By 29 May two bergs had 

 progressed south of Cape Race and grounded on Pig Bank and 

 Ballard Bank. The general drift of bergs once they had entered the 

 area south of 48° N., and west of 52° W., was south by west at speeds 

 varying from 5 to 10 miles per day. 



