1st.Eng.ed., 1998. Xxviii + 492 pp., 43 photo-plates. D.j., 24cm x 16cm. FINE. The epic story of the Allies’ defeat of the German U-boats in May 1943 – ‘Black May’ as the Germans called it - when the Allies finally and decisively gained the upper hand in the Battle of the Atlantic. In that month Germany had the largest U-boat force they had so far sent out into the Atlantic, but during those four weeks the Allies sank 41 U-boats and damaged a further 37, forcing Doenitz to withdraw the survivors from the fray. In this gripping and highly detailed modern assessment of a single month in the Spring of 1943, the author describes the hundreds of separate engagements which took place, drawing on archives from both sides of the Atlantic as well as personal recollections. He describes the vital Convoy ON S5 ; reproduces transcripts of secretly recorded conversations between captured U-boat crew ; tells of the success of RAF Coastal Command’s radar-equipped long-range aircraft over the Bay of Biscay ; the Royal Navy’s Escort groups and their new tactics and new weapons ; and the all important role of Bletchley Park after the Royal Navy captured Enigma and, unbeknown to the Germans, broke their cipher codes.