PART IV - Anti-Submarine Warfare April 1917 to December 1918

Summary

INTRODUCTION

American entry into the war coincided with the worst period of the submarine campaign. In April 1917, sinkings of Allied and neutral merchantmen approached 250000 tons per week, well above the German target. Moreover, the onset of longer daylight raised the prospect of yet higher losses. Most sinkings took place in the Western Approaches but there were substantial losses, too, in the Mediterranean, the English Channel, the North Sea and the Irish Sea. British food stocks were estimated at between three and ten weeks’ consumption, while fuel oil was reduced to six weeks’ supply. The critical level of supplies necessary to maintain the Allied armies and civilian populations was 32 million tons per annum and this mark was being approached rapidly by the end of June. The U-boats were sinking shipping far faster than it could be replaced – Allied building capacity was only 130000 tons per month. The destruction of U-boats was not increasing. Between 54 and 58 had been sunk since the war began and the current rate was about three a month – at a time when the Germans were turning out three per week. The morale of the crews was high and the new boats incorporated many improvements [127, 164].

In view of this dire situation, it is not surprising that Sims’s first report to Washington declared that ‘Control of the sea is actually imperilled’ and that Page should call it ‘the sharpest crisis of the war’. Sims observed that the Royal Navy was ‘dangerously strained’ and Page referred to ‘a great depression in naval circles’ [127, 129, 151, 152, 182]. Jellicoe told Carson ‘we shall be very hard put to it unless the United States help us to the utmost of their ability’ and urged De Chair to ‘keep constantly before the US Authorities the great gravity of the situation’ [130]. A British correspondent of House called it ‘a race against time’ and British leaders from Lloyd George downwards, supported by Page and Sims, urged both the despatch of every available anti-submarine vessel and, more importantly, a huge emergency programme of mercantile construction, estimated at six million tons per annum by Lloyd George. A decrease in sinkings would not enable the target to be reduced as even more shipping would be needed to transport and supply the AEF.