typical Atlantic storm: ‘I couldn’t see anything for the swirling spray. The wind shrieked through the rigging and superstructure. It looked as though we were sailing through boiling water as the wind whipped the wave tops into horizontal spume, white and fuming, which stung my eyes and face. Now and again I caught a glimpse of one of the big merchant-ships being rolled on its beam ends by the huge swells sweeping up under rain-laden skies.’ Butler’s destroyer, Matchless, hove to near a struggling merchantman with a twelve-foot split in its upper deck. Soon afterwards, one of their own men was washed overboard. The captain took the brave, futile decision to turn in search of him. Butler thought: ‘The captain’s gone crazy, he’s going to risk the lives of two hundred men to look for some silly bastard that hadn’t the sense to keep off the upper deck.’ After a few anxious moments, the hopeless quest was abandoned. Then Butler learned that the lost man was one of his own messmates. ‘I was saddened and shocked, filled with remorse about my selfish attitude…“Snowy” was well liked and had the reputation of being a “gannet” who never stopped eating. Never again would we hear him ask cheerfully at mealtimes, “Any gash left?”’
Aboard corvettes, workhorses of convoy escort groups, conditions were much worse, ‘sheer unmitigated hell’, in the words of a seaman. ‘Even getting hot food from the galley to fo’c’sle was a tremendous job. The mess decks were usually a shambles and the wear and tear on bodies and tempers something I shall never forget. But we were young and tough and, in a sense, we gloried in our misery and made light of it all. What possible connection it had with defeating Hitler none of us bothered to ask. It was enough to find ourselves more or less afloat the next day with the hope of duff for pudding and a boiler-clean when we reached port.’
And then there was the enemy. While Germany’s capital ships commanded headlines and their sorties inflicted some injuries, Axis submarine and air forces represented a much graver long-term threat, and the men of both arms displayed courage and skill. U-boats achieved striking early successes, such as sinking the old battleship Royal Oak in Scapa Flow, and wreaking havoc upon vulnerable merchantmen. Churchill as First Sea Lord estimated that the introduction of convoying in 1939 was responsible for a 30 per cent fall in Britain’s imports. Merchant ships were obliged to waste weeks waiting for convoys to assemble. Once ocean-bound, they travelled painfully slowly, and were offloaded on arrival by a lethargic and sometimes obstructive British dock labour force. Many ships that carried commodities in peacetime had to be diverted to move troops and munitions across huge distances by circuitous routes, to avoid Axis air and submarine concentrations – for instance, almost all Egypt-bound cargoes travelled via the Cape of Good Hope. The voyage to Suez lengthened from 3,000 miles to 13,000, while a Bombay-bound ship made a passage of 11,000 miles against the pre-war 6,000.
Until 1943, the Royal Navy was desperately short of escorts and effective technology to hunt U-boats. The British sank twelve German submarines in 1940, and just three in the six months between September that year and March 1941; intelligence and skilful convoy routeing did more to frustrate Admiral Karl Dönitz than did anti-submarine escorts. The Royal Navy was slow to realise the vulnerability of merchantmen off the African coast, where in 1941–42 just two long-range Type IX U-boats achieved some spectacular destruction, partly because they maintained wireless silence and partly because few defensive resources were available. The British were grievously hampered by lack of air support. The RAF’s Coastal Command was short of planes; its long-range Sunderland flying boats suffered from crews’ poor navigational and depth-charging skills, together with technical problems that reduced their effort in 1941 to an average two sorties per aircraft a month. Meanwhile, until 1942 many of the Royal Navy’s destroyers remained committed to coastal defence of Britain.
In the course of the entire war, while 6.1 per cent of Allied shipping losses were inflicted by surface raiders and 6.5 per cent by mines, 13.4 per cent were caused by air attack and 70 per cent by U-boats. The British suffered their first severe blow in the autumn of 1940, when the slow eastbound Atlantic convoy SC7 lost twenty-one out of thirty ships, and twelve out of forty-nine in the fast HX79. Thereafter, the tempo of the undersea war rose steadily: during 1941, 3.6 million tons of British shipping were lost, 2.1 million of these to submarines. Churchill became deeply alarmed. His post-war assertion that the U-boats caused him greater anxiety than any other threat to Britain’s survival has powerfully influenced the historiography of the war. It is scarcely surprising that the prime minister was so troubled, when almost every week until May 1943 he received loss statistics that represented a shockingly steady, debilitating depletion of British transport capabilities.
But the submarine force commanded by Dönitz was weak. Germany’s pre-war industrial planning envisaged a fleet which achieved full war-fighting capability only in 1944. Naval construction was skewed by a focus on big ships: a hundred U-boats could have been built with the steel lavished on the Bismarck. On the eve of war, Admiral Erich Raeder, German naval C-in-C, wrote: ‘We are not in a position to play anything like an important part in the war against Britain’s commerce.’ Until June 1940, Dönitz did not anticipate waging a major campaign in the Atlantic, because he was denied means to do so; the small, short-range Type VII boats that dominated his armoury were designed to operate from German bases. Even when the strategic picture radically changed with Hitler’s seizure of Norway and of France’s Atlantic ports, the Kriegsmarine continued to build Type VIIs. Productivity in German shipyards, hampered by shortages of steel and skilled labour, and later by bombing, fell below British levels. U-boats remained technically primitive. Innovation – for instance, the 1944–45 Schnorkel underwater air-replenishment system – was not matched by reliability: the revolutionary Type XXI sailed on its first war patrol only on 30 April 1945.
Thus, Dönitz’s force lacked mass, range and quality. Just as the Luftwaffe in 1940–41 attempted to deal a knockout blow to Britain with wholly inadequate resources, so the U-boat arm lacked strength to accomplish the severance of the Atlantic link. Germany never built anything like enough submarines to make them a war-winning weapon. Dönitz calculated that he needed to sink 600,000 tons of British shipping a month to achieve a decisive victory, for which he required three hundred U-boats in commission to sustain a third of that number in operational areas. Yet only thirteen U-boats were on station in August 1940, falling to eight in January 1941, rising to twenty-one the following month. This small force inflicted impressive destruction: two million tons of British shipping were sunk between June 1940 and March 1941. But in the same period just seventy-two new U-boats were delivered, far short of the number Dönitz needed. They achieved their highest rate of productivity – measured by tonnage sunk per submarine at sea – in October 1940; thereafter, while many more boats were deployed, their pro-rata achievements diminished.
As the war developed, while the Allied navies grew apace in skill and professionalism, the quality and determination of U-boat crews declined. One by one Dönitz’s aces were killed or captured, and the men who replaced them were of lesser calibre. German torpedo technology was almost as flawed as that of the 1942–43 US Navy. Direction of the U-boat campaign was hampered by changing strategies and impulsive interventions by Hitler. German naval intelligence and grasp of Allied strategy, tactics and technology were chronically weak.
It is a remarkable and important statistic that 99 per cent of all ships which sailed from North America to Britain during the war years arrived safely. Even in the bad days of April 1941, for instance, 307 merchantmen sailed in convoy, of which only sixteen were sunk, together with a further eleven unescorted vessels. In June that year, 383 ships made the Atlantic passage, in convoys of which submarines attacked only one, sinking six ships, along with a further twenty-two unescorted merchantmen. In 1942, by far the most alarming year of the U-boat war, 609 ships were sunk in the North Atlantic, a total of some six million tons. So prodigious was American shipbuilding capacity, however, that in the same period the Allies launched 7.1 million tons of ships, increasing their available pool of thirty million tons.
Yet, as is the way of mankind, the Allies perceived most of the difficulties on their own side. While posterity knows that in 1942 the U-boats inflicted the utmost damage of which they were capable, and that thereafter the tide of the convoy war turned steadily against them, at the time Churchill
