Blood, Tears and Folly: An Objective Look at World War II

The maps were supplemented by a number of diagrams showing the differences between our local time and that in the various areas of operations, charts showing tides and currents and ice and fog conditions with special reference to the north-west Atlantic … A large globe more than three feet in diameter gave a realistic picture of the wide Atlantic as it really is and was of great assistance in determining distances which could be worked out only approximately on ordinary charts, which, where great distances are concerned, make no allowance for the curvature of the earth’s surface.

FIGURE 6 (#ulink_535cbccd-36e0-5123-8d76-2db69815d4dc)

British shipping losses in the first year of the war – Royal Navy and merchant total 452 (#ulink_535cbccd-36e0-5123-8d76-2db69815d4dc)

On that first day of September 1940 his charts showed that his U-boat losses to date – 28 – exactly equalled the number of new boats commissioned in the same period. That still left him fewer than at the start of the war because of the needs of training, repairs, trials and shakedowns. Of his 27 operational U-boats only seven or eight would be at sea on an average day, too few for Dönitz to operate the sort of ‘wolf-pack’ tactics he wanted, though sometimes several boats could be brought together to converge on a target.

The chart recording his successes would have shown an aircraft-carrier, a battleship, three destroyers, two submarines, five auxiliary cruisers and 440 merchant ships estimated at a total 2,330,000 tons. Dönitz used tonnage sunk per U-boat day at sea as a measure of the U-boat arm’s efficiency. By this measure October 1940 was the peak of his success, with five and a half ships sunk each month per U-boat at sea. (The high figures achieved later in the war were sinkings by larger numbers of boats, and Dönitz remained acutely aware of his failure to get back to his 1940 peak.)

The French bases at Lorient, Brest, St Nazaire and La Rochelle were near deep water and difficult for the British to mine. RAF Bomber Command did not mount an all-out bombing campaign against them until it was too late. For in 1941, at Hitler’s command, concrete shelters were constructed over the pens and made so thick and strong that normal RAF bombs had little effect. Virtually indestructible, these pens are still there today. The French show perverse pride in them and permit only their own citizens to look inside.

The Germans also had the benefit of skilled French technicians. Delighting their German masters, the French shipyard workers laboured even harder than their counterparts in Germany. They reduced the turn-around time that U-boats spent in port by no less than 22 per cent. ‘Until this time two and a half boats had been in port for every submarine at sea and the French helped to reduce this figure to a ratio of 1.8:1.’

As German armies consolidated their conquest of France and the Low Countries in the summer of 1940, the British kept many destroyers and other craft in base, ready to repel an invasion of their islands. Convoys sailed with few escorts, and for much of the crossing had to manage without protection. Out in the North Atlantic the U-boats were sinking merchant ships at a dismaying rate. U-boat commanders, with their battered hats and white roll-neck sweaters, were coming home from patrol to report the sinking of forty or fifty thousand tons of shipping. These undersea aces got the same sort of film star treatment in Germany that the Spitfire pilots (often with similarly battered hats and similar white roll-neck sweaters) were enjoying in Britain. U-boat crews were cosseted. French resort hotels were converted to rest homes for them, or they could return to Germany on the special U-boat train that went backwards and forwards with supplies, ammunition and spare parts. If they stayed near their bases, their high pay (with double pay for each day in the Atlantic operational zone) ensured their warm welcome in restaurants, nightclubs and brothels despite their reputation for boisterous behaviour.

From the bases in France U-boat men could strike at ships bringing fuel, wheat and war supplies to Britain from the United States and Canada, as well as beef from South America, while the routes of vital ore from South Africa and oil from Nigeria were almost on their doorstep. The African convoys were seeking safety further west and the transatlantic routes were going ever more northwards into icy seas. The U-boats followed them.

Aircraft: the lonely sea and the sky

Until war started, the British had given little thought to the weapons needed if aircraft were to sink submarines. The Blackburn Kangaroo, a twin-engined biplane used against U-boats in the final weeks of the First World War, could carry four 250-lb bombs. The twin-engined Avro Anson, which in 1939 comprised well over half of RAF Coastal Command’s aircraft, could carry only four 100-lb bombs. Although these were specially designed anti-submarine bombs their efficiency had never been properly tested. The first chance to measure Coastal Command’s anti-submarine bombs came on 5 September 1939, two days into the war, when an Anson of 233 Squadron dropped two 100-lb bombs on a submarine that surfaced off the coast of Scotland. The bombs bounced off the water and exploded in mid-air, causing enough damage to bring the Anson down into St Andrews Bay. The submarine proved to be one of the Royal Navy’s fleet.

A few days later, on 14 September, two Blackburn Skua dive-bombers from the aircraft-carrier HMS Ark Royal attacked the U-30 which had surfaced alongside the freighter Fanad Head while a German boarding party searched for food (the U-boat rations had gone mouldy) prior to opening its sea valves to sink it. Again the anti-submarine bombs exploded in the air, bringing down both planes. The U-boat crew, commanded by Kapitänleutnant Lemp, rescued two of the aviators and then dived with them as prisoners. The next day another Anson was damaged by its own bombs without causing damage to the target. A year later, on 25 October 1940, three Hudson bombers from 233 Squadron subjected the U-46 to a concentrated attack in which one 100-lb anti-submarine bomb scored a direct hit. The U-boat’s pressure hull remained intact and the vessel managed to get back to port.

It is no surprise to learn that the first U-boat sinking from the air was carried out by Bomber Command using ordinary 250-lb general purpose bombs. A Bristol Blenheim on an armed reconnaissance went dangerously low to deliver a determined attack upon U-31, which on that day, 11 March 1940, was undergoing sea trials off Heligoland Bight. One, perhaps two bombs, hit the hull. Everyone aboard, including many dockyard workers, died though the hull was salvaged, refitted and went back into action. At last, a month later, a Fairey Swordfish flying off HMS Warspite did manage to score with two 100-lb anti-submarine bombs, sinking the U-64 at anchor.

In view of the ineffectiveness of the anti-submarine bombs, the airmen decided to throw at the enemy the only other anti-submarine weapon available: the depth charge designed in the First World War. This thin metal drum, packed with explosive, had an adjustable fuse which detonated according to water pressure. A nose and tail were fitted and it was dropped with reasonable success on practice targets, although only large aircraft could carry the depth charge since it weighed 450 lb. Altogether different to the bomb, it was designed to go into the water alongside the target rather than strike it (those that hit a submarine seldom exploded), and since the explosion took place underwater it posed far less danger to the airmen. But such depth charges were not in general supply until the summer of 1941.

In 1939 both sides were acutely short of large long-range aircraft. The Luftwaffe had been forced to use a civil airliner, the Fw 200C Condor, a beautiful machine that in August 1938 had flown non-stop from Berlin to New York and back at an average speed of 205 mph. Pressed into use for long-range maritime reconnaissance, the Condor was not rugged enough for the rigours of military flying.

FIGURE 7 (#ulink_acb1741a-00c2-539b-b00e-a464f7717e30)

Focke Wulf Fw 200C Condor (#ulink_acb1741a-00c2-539b-b00e-a464f7717e30)

The RAF had the equally fine Short Sunderland flying boat, a four-engined machine with a crew of anything up to 13. It came complete with kitchen and beds. Although it looked like the same manufacturer’s civil flying boat, this aircraft was built to a military specification and so was much better suited to a military role than the adapted Condor. One Sunderland, forced down on to a very rough Atlantic, with winds gusting up to 100 mph, remained afloat for the nine hours that it took HMAS Australia to arrive and rescue its crew.

The Sunderland had won headlines a few days after war began when two of them landed on the sea and rescued the 34-man crew of a torpedoed tramp steamer. Any flying boat – let alone one with a crowd of unscheduled passengers – is difficult to unstick from open water. It was a remarkable feat of airmanship, and seamanship too. With a range of almost 3,000 miles at 134 mph the Sunderlands would no doubt have seriously depleted the U-boat flotillas if suitable bombs or depth charges had been available in the early days of the Atlantic battle.

FIGURE 8 (#ulink_97352955-4581-5e3b-9685-24d6e6bba2fb)

Short Sunderland flying boat (#ulink_97352955-4581-5e3b-9685-24d6e6bba2fb)

Since 1936 the United States navy had been using as their patrol plane a reliable two-engined flying boat which the RAF called a ‘Catalina’ after an island near Consolidated’s San Diego plant. The RAF ordered 30 of these aircraft in 1939 and they began arriving in 1941. It was one of these flying boats that sighted the Bismarck on 26 May 1941. The pilot who shadowed the German battleship was actually on a check flight with a US navy instructor aboard.

They were flying out of Lough Erne in Northern Ireland, which in great secrecy had already been allotted funds and materials for conversion to a US naval air base. The official account of the interception seems to have had some expletives deleted:

I was in the second pilot’s seat when the occupant of the seat beside me, an American, said ‘What the devil’s that?’ I stared ahead and saw a dull black shape through the mist which curled above a very rough sea. ‘Looks like a battleship,’ he said. I said: ‘Better get closer. Go round its stem.’ … two black puffs appeared outside the starboard wing tip. In a moment we were surrounded with black puffs. Stuff began to rattle against the hull. Some of it went through and a lot more made dents in it … The only casualties occurred in the galley, where one of the crew who was washing up the breakfast things dropped two china RAF plates and broke them.

During the Bismarck surveillance a Catalina created a Coastal Command record of 27 hours of continuous reconnaissance. The Cat was remembered by those who flew it for its particularly good auto-pilot, which made it possible to endure long hours at the controls of this heavy machine – patrols regularly lasted 17 hours – and meant there could be an extra pair of eyes watching for U-boats. Later, at the direct instruction of President Roosevelt, these flying boats were joined by another Consolidated aircraft: the B-24J Liberator, a four-engined aircraft with extra fuel tanks fitted. Able to carry antenna, radar sets, bombs, depth charges and even searchlights, the Liberator played a vital part in narrowing that mid-Atlantic ‘gap’.

FIGURE 9 (#ulink_d1316936-327a-5cf5-96db-d723a141de0b)

Consolidated Catalina flying boat (#ulink_d1316936-327a-5cf5-96db-d723a141de0b)

Long-range flying was pioneered during the war by hastily trained young men plucked from civilian jobs. RAF Sunderlands flew a thousand miles out over the Atlantic, and did it day after day. When America entered the war Boeing B-17 Flying Fortress pilots, at the end of their US army air force training, flew their Forts to Britain. It was a Catalina delivered to Australia that made the third air crossing of the Pacific. In normal times these events would have made newspaper headlines.

Maritime patrol aircraft needed a very long range, for they had to reach the convoys far out in the ocean before work could start. Once in place, their chief value arose from the fact that U-boats had to remain below when aircraft were present, or risk being bombed. Even a slow 7-knot convoy would soon outdistance a submerged submarine, and a submerged submarine could be detected on asdic.

The start of a convoy’s trouble came when one of a rake of submarines spotted smoke, began trailing it at a distance, and then transmitted signals to bring others. A U-boat forced to submerge might well lose contact with the convoy and would have to cease transmitting.

An unforeseen dimension of the encounter between aircraft and submarine was the fact that land-based aircraft could not pick up survivors in the sea. This brought an unexpected outcome in August 1941 when a Lockheed Hudson bombed U-570 in the open sea to the south of Iceland. The U-boat was one of the large long-range Type IXC vessels that were notorious for the way in which seawater came over the conning tower at above-average speeds or in rough weather. The bombs damaged U-570 enough for seawater to get to the batteries and create deadly chlorine gas: a constant worry for all submarine crews. The U-boat crew signalled surrender with the captain’s white shirt and then found a white board and waved that too. The Hudson circled with guns trained, not realizing that the U-boat could not dive again. While circling the pilot suggested that his co-pilot parachute down as a prize crew, ‘but he didn’t fancy it’ he joked in a BBC broadcast. A Catalina arrived and the Hudson signalled: ‘Look after our sub, it has shown the white flag.’ Ships sent to rescue the submariners arrived just before nightfall and took the U-boat in tow until eventually it ran aground off Iceland. It was refitted and put into action by the Royal Navy as HMS Graph.

Boffins join the navy

During the 1930s scientists in Germany, France, the USA and Britain, working independently and in secret, discovered that a beam of very short pulses, sent and reflected from a target back to a cathode ray tube, would define that object’s bearing and range. It was not advanced technology, and it certainly wasn’t a British invention. Even the Russian armed forces were equipped with radar by the time war began.

The German battleship Graf Spee had excellent gun-laying radar and the Scharnhorst and Gneisenau both used radar to evade HMS Naiad in January 1941. Naiad’s Type 279 radar was outranged by the German radar, so that after one brief visual sighting by the British (who never made radar contact) the German ships were able to keep clear of their pursuers. In the Norwegian campaign the same two German ships had surprised HMS Renown by using gun-laying radar to hit her while remaining concealed in a snow squall.

The Royal Navy began to equip its ships with Type 79 radar in 1939, although at the outbreak of war only HMS Rodney and HMS Sheffield had been fitted with it. These sets were intended for the location of enemy aircraft, and were given to the big ships and to anti-aircraft cruisers such as HMS Curlew, HMS Carlisle and HMS Caracoa. In May 1940 two hundred Type 284 (50-centimetre) gun-laying radar sets were ordered. New urgency was given to radar development when, in the Mediterranean in 1941, ships without it were found to be at a grave tactical disadvantage. The US navy had been fitting radar to its ships since 1940, and in the August of that year, long before the United States went to war, the USN and RN began to share their technology.

At the start of hostilities, German radar was more accurate and sophisticated than that of any other nation. The first radar success of the war was on 18 December 1939 when a formation of 22 RAF Vickers Wellington bombers was detected 70 miles off the German coast. Only ten of the bombers returned.

While British designers concentrated on longer-range sets, the Germans wanted accuracy and, where possible, mobility. In the summer of 1940 a German mobile unit on the Cherbourg peninsula fixed the position of an RN destroyer near the British coast and it was sunk by a Luftwaffe attack.

Radar – or Radio Direction Finding as the British called it at that time – was cumbersome, and the use of delicate glass vacuum tubes, known as valves, made it fragile. Such apparatus was regarded as a land-based, or shipborne, anti-aircraft weapon that could also be used against ships. It was probably the British who first tried another idea. A team under Dr Edward Bowen put an early EMI television receiver into an old Handley Page Heyford bomber and was encouraged by getting a flickered reception from a transmitter. From this they went on to design a small high-frequency set to go inside an Avro Anson aircraft. By 3 September 1937 it could detect big ships at about five miles.

The vital factor in the development of British radar was a willingness to improvise. Priority was given to radar – and other scientific ideas – when radar was credited with having saved Britain from defeat in the Battle of Britain. The Nazi creed gave emphasis to rural traditions and old ‘Germanic’ customs; and the political leaders of the Third Reich were apt to be antagonistic to modern science, sometimes defining it as Jewish. German scientists were not automatically exempted from military service, and civilian scientists assigned to work with the armed forces did not find the welcome that their British counterparts were given. Britain invented the technique of ‘operational research’, which meant scientists (cheerfully nicknamed ‘boffins’)

advising the armed forces on the most effective way to use existing weapons rather than having to devise new ones.

Operational research boffins demonstrated that you could double the size of a convoy without doubling the length of its perimeter; in fact the perimeter of an 80-ship convoy was only one seventh longer than a convoy of 40 ships. Thus big convoys meant more effective use of escort vessels. Moreover average losses decreased from 2.6 per cent to 1.7 per cent when convoys comprised more than 45 ships. This was partly due to the fact that a wolf pack’s activities were limited by the availability of torpedoes, reloading time, stress and fatigue, whatever the size of the convoy.

Operational research also helped decide at what depth a depth charge should be set to explode. The scientists suggested that, given enough time, a U-boat crash-diving usually turned away to escape. Such targets should be abandoned as a lost cause. Depth charges dropped from aircraft should be set to explode near the surface, ensuring the more certain kill of those U-boats attacked early enough. Such ideas brought an immediate and dramatic benefit to British anti-submarine tactics.

When war began, Coastal Command had 12 Lockheed Hudson aircraft fitted with ASV (Air to Surface Vessel) Mark I radar. Better sets – fitted in the larger Armstrong Whitley bombers and Sunderland flying boats – followed. At its best, airborne radar could pick up a U-boat at 25 miles, but these valuable aircraft, with their ineffective anti-submarine bombs, seldom sank U-boats.

The boffins were asked why out of 77 U-boat sightings from aircraft in August and September 1941 only 13 were originated from airborne radar contact. The hastily built equipment was poorly serviced, they said, and operating it was a job assigned to anyone with time to spare. Better training gave aircrews faith in their equipment, and towards the end of 1941 airborne radar became more and more effective. Swordfish biplanes of 812 Squadron Fleet Air Arm showed what it could do by patrolling systematically by day and night against U-boats trying to get through the narrow Strait of Gibraltar in to the Mediterranean. One U-boat was sunk and five damaged so badly that they had to return to base.

In addition, the Royal Navy’s big ships were being fitted with its own more sophisticated gun-laying as well as air-warning radar, yet the range of British radar sets was still less than that of an alert lookout on a clear day. The urgent problem was to develop something that could be fitted into an escort vessel, such as a corvette, and detect the conning tower of a surfaced U-boat at night.

Dr S. E. A. Landale was one of the team that set up a short-wave centimetric radar on the cliffs at Swanage and traced a submarine seven miles away. He found practical difficulties when fitting his radar into a ship: ‘Corvettes are very wet and in rough weather the discomforts, inconvenience and inflow of water whenever the office door was opened had to be experienced to be believed.’

Antenna systems had to be protected against the weather. More problems arose from the rolling and pitching and the effects of engine vibration and of gunfire. Even so, by the end of 1941 the Type 271 radar had been designed, one hundred were built and fifty ships were equipped with it. This was the first operational magnetron-powered centimetric radar in the world. In use it was a revelation: it could even locate the top of a periscope. No longer could a surfaced U-boat sail at night with impunity.

Fragile but lethal: U-boats at work

But in September 1940, long before such sophisticated devices played a part in the battle, Admiral Dönitz became agitated enough to tell his staff that ‘It will not be long before the entire U-boat fleet is lost on our own doorstep.’ His distress was due to two factors which still today have scarcely been recognized, says one of the most reliable historians of the U-boat war, J. P. M. Showell. Dönitz was distressed about the number of boats lost to British submarines and mines while crossing the Bay of Biscay. The dangers of the Bay had led U-boat crews to call it Totenallee, or death row.

Leaving aside the efficacy of the mines and submarines, the fears that Dönitz showed were to have an immediate and immense effect upon the U-boat war, for he told his crews to send a radio signal as soon as they had traversed the Bay safely. This signal was transmitted when the U-boat passed the 10 degrees west line (later this was changed to 15 degrees west). The crews looked forward to this stage of the journey, for their daily rate of pay increased. The Admiralty’s Submarine Tracking Room personnel also liked it for, using HF/DF, an exact longitude could now be added to an approximate latitude for every U-boat going on patrol. With this ‘fix’ pinned in to the map it was usually possible to guess which of the convoy routes the U-boat was heading for.