Convoy TM-lo Consisting of 9 tankers and 4 escort vessels, 

 bound from Trinidad to Gibraltar, the convoy lost 7 of its 

 tankers to U-boats while out of range of shore-based air- 

 craft , It was becoming more and more apparent that defeat 

 of the U-boats could not be achieved until virtually un- 

 interrupted air cover for convoys was providedo 



February 1943 $ with losses from U-boats totaling 63 

 vessels of 359 ^,000 tons, proved that the December and 

 January lull had only been temporary,, Approximately half of 

 the Atlantic losses were in the northwest area_, where wolf- 

 packs of 20 U-boats and more were in action. As a counter- 

 measure VLR (Very Long Range) aircraft began operations 

 during the month in an effort to provide air cover over the 

 gap, 



March 1943 saw world-wide losses from U-boat attacks 

 totaling 107 vessels of 627 9 000 gross tons. U-boat packs 

 were frequently outnumbering escort vessels two to one On 

 one occasion Convoys HX-229 and SC-122;, which were routed 

 closely together j, ran into a pack of 40 U-boats and in the 

 ensuing action lost 20 ships , VLR's finally were able to 

 come to the rescue and force the U-boats to retire This 

 was on 20 March ? a date which is sometimes referred to as the 

 decisive date in the antisubmarine war, since thereafter in- 

 creasingly energetic Allied measures succeeded more and more 

 in blunting the offensive power of the enemy*, and losses of 

 merchant vessels declined at an ever increasing rate. 



It was during March 1943 that the USS B0GUE, first United 

 States escort carrier s started to operate in the North Atlantic, 

 Also in that month it was agreed that starting in May the 

 United Kingdom and Canada should be responsible for the secur- 

 ity of convoys across the North Atlantic, with the United States 

 providing certain air and sea forces. 



Shipping losses from U-boats in April 1943 fell to 56 

 ships of 328 s 000 gross tons, with losses in the Northwest- 

 Atlantic only half of what the}?- were in March, Japanese sub- 

 marines sank 6 ships in the Southwest Pacific off the east 

 coast of Australia, The month saw 17 U-boats sunk in the 

 Atlantic for a record high to that date. Five antisubmarine 

 "killer groups" were in action in the North Atlantic, two of 

 them with their own escort carriers. These groups had as 

 their mission the destruction of U-boats and were not tied 

 down to convoy duty. 



- 74 



