All the hard work proved a worthwhile investment. By the end of September some eighty-three inward convoys had arrived, totalling 1,306 merchantmen. Only eighteen ships had been sunk, eight of which had been lost after dropping out of their convoys. Similarly just two ships were sunk in the fifty-five outward-bound convoys. There was a further boon as the convoys also allowed a more effective use of the naval intelligence still pouring in from Room 40 and the wireless directional stations. This provided a wealth of information as to the approximate location of German submarines which seemed to have no concept of wireless silence. Although too geographically vague to be of much use for the multifarious patrols engaged in the generally fruitless task of tracking down and sinking U-boats, it did greatly assist convoys as they could be diverted round the dangerous waters where U-boats were known to be operating. The U-boats found the oceans bare and empty as a group of ships sailing in a tightly packed convoy were only marginally more visible to a submarine than a single ship. Even as early as August 1917, Lieutenant Commander Alfred Saalwächter commanding the U-94, realised the impact of the new system.
The convoys, with their strong and efficient escorts making an attack extremely difficult, are in my view quite capable of drastically reducing shipping losses. The chances of sighting a convoy of seven ships is less than that of sighting seven independent ships. In the case of a convoy it is mostly possible to only fire on one ship. For any ship torpedoed in convoy, the chance of immediate help is a factor of considerable importance to morale.
Lieutenant Commander Alfred Saalwächter, U-94
When they did encounter a convoy, the submarine commanders were forced to take excessive risks to score their kills, all the while harried by armed escorts and liberally bespattered with depth charges. The log book kept by Lieutenant Commander Hans Adam of the U-82 reveals the chances that had to be taken and difficulties surmounted to make a successful attack on a convoy in September 1917.
I shot past the bows of this steamer towards Steamers 4 and 5. Steamer 4 I hit. Steamer 2 had hoisted a red flag, which was probably to announce the presence of the U-boat; for several torpedo boats make for the steamer. As there was no chance of firing from the only remaining usable tube (stern tube), I dived. The destroyers dropped about ten depth charges; one burst pretty near the stern. The attack was rendered very difficult by the bad weather, swell, seaway and rain squalls. The success of the attack was due to the excellent steering under water. Made off noiselessly south-east under water. 4.45 pm rose to surface. I try to come up with the convoy again, as it is still to be seen. But a destroyer forces me under water again. 6.37 pm rose to surface. Two destroyers prevent me from steaming up. Owing to heavy seas from south-east it is impossible to proceed south so as to get ahead of them. Moreover, sea and swell make it impossible to fire a torpedo. Therefore gave up pursuit.
Lieutenant Commander Hans Adam, U-82
Gradually the rate at which Allied shipping was being sunk began to fall in a direct proportion to the number of ships travelling in convoy; at the same time the numbers of U-boats sunk began to rise. Almost despite itself, the Admiralty had stumbled across the solution to the submarine crisis. Nevertheless, it was all too late for Jellicoe: exhausted by his efforts and dogged by the enmity – or worse, ill-disguised contempt – of both Lloyd George and Geddes, he would be finally dismissed by Geddes on 24 December 1917. The new First Sea Lord, Vice Admiral Sir Rosslyn Wemyss, had a far greater residual energy and was able to build on the sure foundations that Jellicoe had laid. Wemyss would continue Jellicoe’s reforms within the Admiralty, building a logical staff structure that allowed the proper delegation of decisions and responsibility.
By the end of 1917 one of the great questions of the war had been answered: Britain would not after all be starved out. The failure of their submarines to achieve their ambitious targets resulted in a severe blow to German morale and the German High Command realised that the war would not be won by the U-boats. The Battle of Jutland had confirmed that the British blockade of Germany would endure. The 1917 defeat of the U-boats, however, would ultimately result in the 1918 Spring Offensives designed to knock Britain out of the war on land before the Americans could arrive in strength on the Western Front.
By 1918, the Americans were firmly welded into the Grand Fleet which would move south to Rosyth, in the Firth of Forth, at Beatty’s instigation in April 1918. The Americans contributed the five fast dreadnoughts of the 6th Battle Squadron, under the command of Rear Admiral Hugh Rodman, which were soon integrated into the fleet. Rodman showed a refreshing willingness to conform to British methods of tactics, gunnery and signals, recognising the value of the long years of war experience possessed by the Royal Navy. This stood in sharp contrast to the attitude adopted by General John Pershing and the American Expeditionary Force on the Western Front, who blatantly ignored the advice of British and French commanders at every turn.
In the war against U-boats, the convoy system was now in full swing and operating with ever-increasing effectiveness. Submarines were hunted down with a remorseless savagery. For the U-boat crews it could be a terrible ordeal, as Captain Lieutenant Johannes Speiss, by this time in command of the U-19, experienced off the Scottish island of Oversay on 15 April.
At 8.25 pm, I cautiously ran out the periscope in order to make a general survey, since the Foxglove must have been passed according to my calculations. To my astonishment I saw him dead ahead of us about 1,000 metres distant and apparently stopped. ‘Periscope in!’ ‘Submerge to 20 metres!’ At the same moment BRUMMMS … As a result of the shock I almost fell into the central station. The depth charge landed right near the conning tower, everything was shaking. ‘Submerge deeper!’ ‘Full speed!’ BRUMMMS … Damn, that was some explosion, the lighting globes broke. ‘Cut in emergency lighting system! Noiseless speed, course west!’ The storage batteries are almost discharged. Twenty minutes pass and everything is quiet. Apparently the listening devices have lost us and there is no oil streak or propeller wash on the surface to betray the boat. I wanted to renew the attack and at first came up towards the surface very cautiously. Suddenly BRUMMMS … right on top of us! BRUMMMS … somewhat further away. He has lost us again. Deeper with the boat. ‘All hands forward!’ BRUMMMS … BRUMMMS … these damned charges. BRUMMMS … another shock, everything was knocked – we had touched bottom. ‘Stop the engines! Flood all tanks, stay on the bottom!’ The depth indicator shows 50 metres. The boat has negative buoyancy and remains motionless on the bottom. BRUMMMS … another depth charge, probably dropped on the water eddies we stirred up, the water must be very clear for him to see so plainly. BRUMMMS … another one. ‘Stop everything, in the boat, so that he cannot hear us!’ The situation was more than critical. Quite overcome by the severe explosions we sat, small and angry, on the bottom of the Atlantic Ocean where fortunately the water was somewhat shallow.
Captain Lieutenant Johannes Speiss, U-19
In the end Speiss and his men were very lucky as the escort vessel moved off. Had it not done so, with his electrical batteries almost totally expended, Speiss would have had no choice but to blow the U-19’s tanks, surface and accept his fate.
One incident among hundreds of clashes between submarines and escort vessels occurred on 31 May 1918 when a convoy of some thirty merchantmen was being escorted past Flamborough Head on the east coast of Yorkshire by a conglomeration of armed whalers and trawlers led by Lieutenant Geoffrey Barnish aboard the destroyer Fairy. Suddenly, not far off Bridlington, Barnish heard a loud thump from the convoy and rushed to the bridge to find that the steamer Blaydonian had collided with a submarine. At first Barnish was in a quandary.
In the past we had all had one or two scares over our own submarines suddenly appearing on the surface after their patrol in the Bight, and wanting the bearing and distance of Middlesbrough or the Tyne. I couldn’t understand a German submarine being in this position, so you can well imagine my extreme anxiety. We made challenge after challenge, while all the time we were rapidly approaching our friend or foe. Then I decided we must cripple her, so that, if she did turn out to be British, our own unfortunate fellows would have a chance to save their lives. With that object in view, I ordered the torpedo coxswain (William James Spinner) to steer for her stern, or what I thought to be her stern. We were very close to her by now, and I cannot express to you my relief when I heard a voice from her conning-tower calling, ‘Kamerad! Kamerad!’ I knew exactly what to do now, and quickly ordered the coxswain to port the helm in order to hit her in a more vital spot. But we were too close for the helm to have any effect, and quickly passed over the stern of our enemy. I don’t remember feeling any considerable force of impact at this time, and we probably damaged ourselves more than we did him. However, on passing over him, I determined to renew the attack by ram, and, sending the gunner aft to open fire with our after gun, proceeded to turn the Fairy round. The submarine fired her gun but we shelled her from point blank range with the after 6-pounder. In all, forty direct hits were made. The Germans on the submarine’s bridge now jumped into the water as we came on again with our ram. I always remember wondering how far back our bows would be pushed in, and with these feelings I backed to the wheel and kept my hand on the coxswain, probably deriving a feeling of comfort, as well as knowing that the coxswain would do what I wanted him to do with my hand directing. The destroyer’s bows struck the U-boat close beside the gun. We on the bridge found ourselves all mixed up on the deck. How far we pushed our stem in I don’t really know, for the next thing I realised was that our fore-deck was under water and the submarine had disappeared, leaving two Germans calmly standing on our submerged forecastle with their hands held up. We picked up three more later.
Lieutenant Geoffrey Barnish, HMS Fairy
They would soon be back in the water! Sadly, the Fairy was one of the very first destroyers, built back in 1897, and the damage she suffered was such that she too would soon join her erstwhile adversary beneath the waves.
The net and mine barrage was also being steadily extended to try to prevent U-boats from gaining access to the open seas. Much work was carried out on the barrage across the Dover Straits while a far more ambitious project created a new Northern Barrage stretching 240 miles from the Orkneys across to the Norwegian coast. This was never really effective due to practical problems with the mines, which were not only laid too deep to affect submarines on the surface but also had an disquieting tendency to self-detonate in chains of spectacular explosions. Yet the Northern Barrage, for all its faults, was still a stern test for the nerves of U-boat crews, who were forced to pass over or through it twice on every voyage.
The ships of the 10th Cruiser Squadron had been ploughing their lonely furrows across the northern waters since 1914. The squadron continued its low-key but important role in enforcing the naval blockade on Germany. The blockade had been steadily tightened by more patrolling cruisers augmented by the ever-useful armed trawlers. The careful monitoring and control of the passage of neutral cargoes by direct inspection, coupled with the merciless application of economic power vouchsafed through British control of steamer coal supplies, gradually brought the neutral countries to heel and they ceased to attempt blockade running. As the war went on it had also become clear that neutral shipping companies could make far more money trading legitimately without recourse to blockade running and risking the wrath of the British. Finally, the combination of the entry of the United States into the war, coupled with an effective convoy system, removed the need for the northern patrol. Its armed merchant cruisers would gradually be reassigned to convoy escorts between June 1917 and January 1918. The patrol endured only in skeleton form with the trawlers and drifters that tended to the net and mine barrage across the North Sea.