Wj y 1. !: was ■■ crucial month, Some 120 U-boats we -e - b 

 "<■" In the Ai Lantic, and s iecisive battle took place on 4 Kay 

 bet a r ) Convoy OI-IS-5 and a >ack of about 10 U-.bc t . The con- 

 voy sonsisted i f seme 30 ships and 1 stragglers. Ar avers e 

 of i escort vessels was present during the ngagement. Durj 

 the afternoon of I May, despite bad weather, aircraft of the 

 RCAP carried t two attacks, one of them which sank one of 

 the U-boats. Shortly after m.i Inight, two U-boats la ir hed 



ajor attacks nd ] 12 ships. On 5 Kay, lue to 1 ['vie it] er, 



air cover could be provided for only a brief 'y' le, but y .' I- 

 n.3 -ht the ■■■ t] ped and from then on the escorts had tl e 



uppi r md. Durin '~ n 3 course of tl 3 ni vu tl ey fru ' . ; ted 

 about twenty-four attacks by U-boats without suffering any 

 losses and a t the same time inflict 1 , evere e on the 



it least 5 U- 1 oats being considered sunk. 



After 17 May no ship was lest in the Atlantic north of 

 45 degrees north, latitude. World-wide losses to U-boats in 

 May lecreased to 50 ships of ? 35,000 gross tons. T' e r : her 

 of U-boats surd: during the month readied a recor ;h of 14, 



with 38 of the sinkings in the Atlantic. Shore-based aircraft 

 accounted fcr more than half of the U-boats sunk iurin the 

 month, while carrier-based aircraft participated in three of 

 the attacks in i] ch the submarine was considered bo have ".eer 

 sunk. z" the end of May the average number of U-bo( ts at sea 

 in the Atlantic had dropped ' ibor^ °5 ar 3 for tl e first ti. . 

 it was noticeable that U-boats were a? T 1 :g to press home 

 attacks even "hen favorably situated bp do so. 



By June 194 >, the U-b< at 3 r< tired frc i the a rfcfc 



At 1 title convo:/ routes and they succeeded in sinkin ; only 20 



lips of 96,000 ros i tons luring the month. At the ss le 

 -' : le, IS U-boats sunk, 1G by Allied • '.aft. 



Mo smi 11 . ■ rt of tb si :cess of Allied aire ' . _:s- 1 " 

 U-b< - 1 r ivas lue t< the '''. 'O 1 s I microwave radar enuipmei 

 with /hich they were fitted. fhe Ail"-; ■ ': adu - - " : :/a- 

 wave radar aught the CJermans flat-footed. For some unex- 

 plained reason they failed u o ^ues the sort of improvement 

 which the Allies hi made in their radar sets, and in attempt- 

 ing to sol .a; the problem, tl ey ran up a nv ' p c^ )1 : " alleys. 

 Pailir 4 " r ;one up wi ' i technical solution the Germans sou ,_ t 

 a tactical answer by >rov3 lin , their U-boats n h ' ' - ivier anti- 

 aircraft irnament so that they might stay or the and 

 fight it c it when r h 1 ted by Allied a: r:.r.; i 4 - » T' ou .' o le 

 planes were lost, the principal result of this ch ir s ir tac- 

 :s wi " to provide Allied flyers with more and bett r t :\ its, 



■ -r j^» < 



75 



