Tag Archives: WW1

Victory over the U-boats

On 21 October 1918 Admiral Reinhard Scheer, the German Chief of the Admiralty Staff, ordered all U-boats to return to base. This ended the German campaign of unrestricted submarine warfare, which meant sinking merchant ships without warning, that had begun on 1 February.[1]

Scheer’s orders were obeyed by almost all U-boat captains. UC 74 (Oberleutnant Hans Schüler) sank the 85 ton Greek sailing ship Aghios Gerasimos by gunfire in the Eastern Mediterranean on 23 October and a number of merchant ships were sunk by mines laid by UC 74 after 21 October off the Suez Canal. Other ships were sunk after 21 October by mines laid earlier.[2]

Admiral Henning von Holtzendorff, Scheer’s predecessor, had argued that the Germans had to break the British economy in order to win the war and this could be achieved by destroying 600,000 tons of merchant shipping per month for five months, which would cut British trade by 39% within five months. The Germans were aware that this might bring the USA into the war against them but thought that it would not be able to replace the lost merchant shipping and that there would be insufficient transports to take US troops to Europe.[3]

The U-boats’ best month before February 1917 was October 1916, when they sank 341,363 tons of merchant shipping according to German records. There are some differences between British and German figures but they are not large. German ones are slightly higher over the whole war but are lower in some months. V. E. Tarrant argues that the German numbers are the more accurate and they are quoted here.[4]

As shown in the table below, the Germans achieved their target of sinking 600,000 tons of shipping in only three months: April, May and June 1917. However, the 860,334 tons sunk in April meant that the average for the first seven months of unrestricted submarine warfare was 612,310 per month. Von Holtzendorff’s belief that this level of loss for five months would break the British economy was proved to be wrong.

These figures are for ships from all countries, not just Britain sunk by U-boats, including by mines laid by U-boats, but excluding ships sunk by surface raiders and aircraft.

Month Gross tons
Aug-14
Sep-14
Oct-14 866
Nov-14 2,084
Dec-14
1914 Total 2,950
Jan-15 17,577
Feb-15 22,785
Mar-15 89,517
Apr-15 41,488
May-15 126,895
Jun-15 115,291
Jul-15 98,005
Aug-15 182,772
Sep-15 136,048
Oct-15 86,064
Nov-15 167,523
Dec-15 107,739
1915 Total 1,191,704
Jan-16 49,610
Feb-16 95,090
Mar-16 160,536
Apr-16 187,307
May-16 119,381
Jun-16 93,193
Jul-16 110,728
Aug-16 163,145
Sep-16 231,573
Oct-16 341,363
Nov-16 326,689
Dec-16 307,847
1916 Total 2,186,462
Jan-17 328,391
Feb-17 520,412
Mar-17 564,497
Apr-17 860,334
May-17 616,316
Jun-17 696,725
Jul-17 555,514
Aug-17 472,372
Sep-17 353,602
Oct-17 466,542
Nov-17 302,599
Dec-17 411,766
1917 Total 6,149,070
Jan-18 295,630
Feb-18 335,202
Mar-18 368,746
Apr-18 300,069
May-18 296,558
Jun-18 268,505
Jul-18 280,820
Aug-18 310,180
Sep-18 171,972
Oct-18 116,237
Nov-18 10,233
1918 Total 2,754,152
Grand Total 12,284,338

Source: Tarrant, V. E., The U-Boat Offensive, 1914-1945, (London: Arms and Armour, 1989), pp. 152-53. Originally from Der Krieg zur See, 1914-15, vol v: Der Handelskreig mit U-booten.

The losses were stemmed by the adoption of various counter-measures of which the introduction of convoys was the most important. Convoys had been used in previous wars and for troopships in this one. The Admiralty opposed them for a number of reasons:

Code breaking and radio direction finding could enable it to track U-boats. This had worked against surface raiders but was ineffective against U-boats because they could not be detected once submerged except by spotting their periscopes or torpedo tracks

An armed merchantman could avoid torpedo attack by zigzagging and fight off a gun attack by a surfaced U-boat.

Merchantmen would not be able to keep station, especially at night. In fact convoys were in areas where U-boat attack was unlikely for most of their journeys, giving them time to practice formation sailing.

Ships would be delayed in sailing. This was false as ships were already delayed by reports of U-boats near their ports.

Convoys would give U-boats an attractive target as they assembled in open seas. The US entry into the war meant that they could assemble in US ports. They could in any case have done so at Bermuda or Halifax, Nova Scotia.

Convoys would concentrate targets together, so would require to be escorted by as many as one destroyer per merchant ship. Allocating this number of destroyers to convoy escort would mean that the Grand Fleet would have to stay in port. Only eight to 10 escorts were actually needed for a 20 ship convoy and smaller ships than destroyers proved to be adequate convoy escorts.[5]

It was actually almost as hard for a U-boat to spot a convoy as it was for it to find an independent ship. According to Vice Admiral Sir Arthur Hezlet, a British WWII submarine captain, a ship could be spotted from 10 miles away. A 20 ship convoy would be two miles wide so could be seen from 11 miles away. Convoys therefore meant that U-boats would find fewer targets, not more. Even if a U-boat spotted a convoy, it would probably have time to  torpedo only one, at most two of its ships and would be counter attacked by the escorts. The British also used radio direction finding to avoid U-boats.[6]

This was confirmed by Karl Dönitz, commander of Germany’s U-boats in WWII and a U-boat captain in WWI. He wrote that ‘[t]he oceans at once became bare and empty…for long periods…the U-boats…would see nothing at all.’ When a convoy did appear, the ‘U-boat might well sink one or two of the ships, or even several; but that was but a poor percentage of the whole.’[7] It would also be vulnerable to counter-attack by the convoy’s escort.

The British had been using convoys in the war. As well as troopships, ships sailing between England and the Netherlands had been convoyed since July 1916 because of the risk of destroyer attack. Ships carrying coal from Britain to France were convoyed from February 1917 at the request of the French. The Admiralty insisted on calling the convoys controlled sailings.[8]

The French coal convoys had been organised by Commander Reginald Henderson.[9] He obtained figures from the Ministry of Shipping that showed that the number of ocean going ships sailing to and from the UK was much lower than realised.

The Admiralty had included short voyages made by small, coastal ships in its reports of the number of ships calling at British ports in order to make the Germans think that the sea traffic to the UK was too great for the U-boats to destroy. The 2,500 voyages each way per week claimed was too many to convoy but the true number of ocean going ships arriving and leaving was 120 to 140 per week.[10]

On 25 April 1917 the War Cabinet decided that the Prime Minister, David Lloyd George, should visit the Admiralty in order to find out what it was doing about U-boats. Lloyd George and his colleagues were in favour of convoys but the Admirals had resisted them. However, the next day Vice Admiral Alexander Duff, head of the Admiralty’s Anti-Submarine Division, who now had Henderson’s figures, submitted a paper to the Admiralty stating that ‘[i]t seems to me evident that the time has arrived when we must be ready to introduce a comprehensive scheme of convoy at any moment.’[11]

Convoys would need 70 escorts. Only 30 destroyers were currently available but more would be built by the time that convoys could be fully organised and USN ships would soon be available.[12]

The introduction of convoys did not eliminate shipping losses but it reduced them sharply, from 5% of sailings in the UK in April 1917 to 0.5% by the end of the war. Some ships continued to sail independently and suffered heavy losses.[13]

A large number of aircraft were allocated to anti-submarine warfare in home waters: an average of 189 aeroplanes, 300 seaplanes and 75 airships in the last six months of the war, with an average of 310 being available each day. Their bombs were too small to sink U-boats but they had a significant deterrent effect. In 1918 U-boats attacked only six convoys with air escorts, sinking only three ships. Over the whole war only five ships were sunk in convoys with both air and surface escort.[14]

The Americans and British were also able to build new ships more quickly than the Germans had forecast. The US entered the war with a relatively small shipbuilding industry but rapidly built one, including constructing accommodation for workers and public transport to take them to work. The British made the Admiralty responsible for both naval and merchant shipbuilding, so that it could make the necessary trade-offs. These including suspending construction of three of the four Hood class battlecruisers in order to build more merchantmen. Sir Eric Geddes, a businessman who had solved railway supply problems behind the Western Front was made Controller of the Admiralty, putting him in charge of the materiel side of the navy. This job was normally done by the Third Sea Lord, an admiral. Ships were built to standardised design.[15]

Merchant shipping construction (tons)

1915 1916 1917 1918
UK          1,000,000         600,000          1,800,000   2,400,000
USA             250,000  n/a          1,500,000   4,500,000

Source: Friedman N., Fighting the Great War at Sea: Strategy, Tactics and Technology (Barnsley: Seaforth, 2014), pp. 284-86.

About 1,700,000 tons of Austrian and German merchant shipping interned in US ports were requisitioned by the US government. They included a number of liners, which transported US troops to France. Amongst them was the giant Vaterland, renamed the Leviathan in US service.[16]

The U-boats failed to stop over 2,000,000 US soldiers sailing to Europe, 10% of them on board the Leviathan. Two eastbound troop transports were sunk by U-boats and another accidentally by collision. Three returning to the USA to collect more troops were also sunk. The total of US soldiers killed by U-boats was less than the 700 who died as a result of influenza caught on the voyage.[17]

German U-boat construction in 1918 was only able to keep pace with losses. They had 224 [Sondhaus] or 226 [Gibson and Prendergast] under construction at the end of the war and completed 13 in October 1918. The hoped to complete 30 a month in 1919. However, they were struggling to man their new boats. U-boats needed experienced captains and fully trained crew: the six most successful U-boat captains in terms of tonnage sunk and 14 of the leading 18 survived the war. Consequently, the Germans refused to cut the training programme given to men before they were assigned to an active U-boat. About two dozen of those under construction at the end of the war could have been commissioned had trained personnel been available.[18]

The U-boats inflicted severe damage to Allied shipping but their attempt to blockade the UK failed and brought the USA into the war against Germany.

 

[1] L. Sondhaus, German Submarine Warfare in World War I: The Onset of Total War at Sea (Boulder MD: Rowman & Littlefield, 2017). Kindle edition, location 4855.

[2] Ibid. Kindle locations 4861-68.

[3] D. Steffen, ‘The Holtzendorff Memorandum of 22 December 1916 and Germany’s Declaration of Unrestricted U-Boat Warfare’, Journal of Military History 68, no. 1 (2004).

[4] V. E. Tarrant, The U-Boat Offensive, 1914-1945 (London: Arms and Armour, 1989), pp. 152-53.

[5] N. Friedman, Fighting the Great War at Sea: Strategy, Tactics and Technology (Barnsley: Seaforth, 2014), pp. 274-78.

[6] Original source A. R. Hezlet, The Submarine and Sea Power (London,: 1967), pp. 94-95; Quoted in A. J. Marder, From the Dreadnought to Scapa Flow; the Royal Navy in the Fisher Era, 1904-1919, 5 vols (London: Oxford University Press, 1961-70). vol v, pp. 88-89.

[7] Original source K. Doenitz, Memoirs: Ten Years and Twenty Days (London,: 1959), p. 4;  Quoted in Marder, From. vol. v, p. 89.

[8] Friedman, Fighting, pp. 276-77.

[9] C. E. Fayle, Seaborne Trade, 3 vols (London: HMSO, 1920). vol. iii, p. 100.

[10] J. S. Corbett, H. Newbolt, Naval Operations, 5 vols (London: HMSO, 1938), p. vo. v. p. 18.

[11] Ibid. vol. v, p. 19.

[12] Ibid. vol. v, pp. 18-19.

[13] Marder, From. vol. v, p. 87.

[14] Ibid. vol. v, pp. 91-93.

[15] Friedman, Fighting, pp. 284-86.

[16] Ibid., p. 286.

[17] P. G. Halpern, A Naval History of World War I (London: UCL Press, 1994), p. 437.

[18] R. H. Gibson, M. Prendergast, The German Submarine War, 1914-1918 (London: Constable, 1931), p. 363; Sondhaus, German. Kindle locations 4497-4513.

Advertisements

3 Comments

Filed under War History

The Dover Straits in the First World War

Origin of the Dover Patrol

At the outbreak of war the main British naval force in home waters was the Grand Fleet, based in Scotland. There were, however, four different forces based in the south east of England: the 1st and 3rd Destroyer Flotillas under Commodore (T) and the 1st Submarine Flotilla under Commodore (S) at Harwich; Cruiser Force C at the Nore; the 6th Destroyer and 2nd and 3rd Submarine Flotillas under the Admiral of Patrols at Dover; and the Channel Fleet of 20 pre-dreadnought battleships. These forces were not under a single command.[1]

The 6th Destroyer Flotilla of two light cruisers and 20 destroyers was responsible for the defence of the Dover Straits and was named the Dover Patrol.[2] The loss to U-boats of the cruiser HMS Pathfinder off Berwickshire on 5 September 1914 and of three armoured cruisers of Force C in the southern North Sea on 22 September showed the importance of the Patrol Flotillas in anti-submarine warfare. At the same time, the work of the Admiral of Patrols was becoming more complex, including minelaying, prevention of enemy minelaying and organising the transport of British troops to France and Belgium and the evacuation of Belgian refugees. On 7 October it was decided that the Dover Patrol should become a separate command. Rear-Admiral Horace Hood took it over six days later.[3]

Hood was replaced by Vice Admiral Reginald Bacon in April 1915. Bacon later wrote a two volume history of The Dover Patrol, which is now out of copyright and available to read at Naval-History.net or to download at The Internet Archive.

Bacon listed the achievements of the Dover Patrol: drifters, crewed by pre-war fishermen, maintained anti-submarine nets, which stretched for 45 miles in 1917; trawlers, also crewed by fishermen swept for mines across 250 miles per day; 120,000 merchant ships passed through the straits with light losses; 5,600,000 troops crossed the Channel without loss; the enemy held coast was bombarded from sea 28 times from ranges of up to 15 miles versus a maximum of 12 miles on ranges in peacetime; examination of merchant ships; and laying of minefields.[4]

The first anti-submarine drifters arrived at Dover in January 1915 and there were over 130 of them there by June. They dragged an average of 1,000 yards of nets with a mesh pattern of 10 foot squares to a depth of 120 feet. The straits were a maximum of 21 miles wide and 180 feet deep, with an average depth of 108 feet. This meant that 36 drifters could in theory block the passage, but in practice tides and current made the task of such small craft difficult even in good weather. They were at best armed with a 6 pounder gun and sometimes with just a machine gun, requiring them to be protected by destroyers and armed auxiliary steamers. German records show that U8, scuttled on 4 March 1915 after being caught in the nets, was the only U-boat lost to the Dover barrage in 1915 or 1916. It did, however, force the larger U-boats that were based in Germany to take the longer route round Scotland to the Atlantic, with the smaller UB coastal submarines and UC minelayers based in Flanders using the shorter route through the Dover Straits.[5]

Mine Warfare

The Allies used mines to combat U-boats but U-boats also laid mines. The 15 boats of the UC I class carried 12 mines but had no deck gun or torpedo tubes. The 64 UC II class boats carried 18 mines and had two bow and one stern torpedo tubes. They initially had no deck gun although some were fitted with a 105mm gun in 1918. The 16 UC III class boats that were commissioned had 14 mines, the same torpedo armament as the UC IIs and either an 88mm or a 105mm gun.

Most German mines laid in British waters were laid by U-boats. In the second half of 1916 an average of about six merchant ships were sunk per month in British waters. This increased to 10 in the first half of 1917 but fell back to four in the second half of that year. On average 178 mines were swept in each month of 1916, rising to 355 in 1917. Even the English Channel was too big an area to sweep completely and only about 10 per cent of the waters around Dover could be swept regularly.[6]

As an example of the size of the Dover Patrol, in October 1916 it comprised:

The Auxiliary Patrol of 2 yachts, 78 trawlers (56 fitted as minesweepers), 10 paddle minesweepers, 130 net drifters, 24 motor launches and 5 motor boats.

The 5th Submarine Flotilla of the light cruiser HMS Arrogant and 10 submarines.

The 6th Destroyer Flotilla of the light cruiser HMS Attentive, 33 destroyers of 400-1,000 tons, 12 monitors with 7.5 to 15 inch guns, 12 gun or patrol boats, 5 paddle minesweepers and a seaplane carrier.

In late October the light cruiser HMS Carysfort and the 8 L class destroyers were detached from Harwich.[7]

The Germans made several attacks by destroyers on the Dover Straits. Click on the links for more details of the larger attacks.

The first of these, on 26-27 October 1916, resulted in the sinking of the old destroyer HMS Flirt, called a 30 knotter after her designed speed, the transport Queen, six drifters, a trawler and serious damage to the destroyers HMS Nubian and Amazon. The Germans suffered no losses but missed opportunities to do more damage. The German success was helped by their previous inactivity, which made the British complacent. This action showed that the barrage had limited effect, as 14 British destroyers had crossed it without being damaged.

The Dover Patrol was reinforced by destroyers from the Humber and Harwich. Destroyers had then to be sent from the Grand Fleet to the Humber. This meant that the Grand Fleet might have had to leave part of the 4th Battle Squadron behind when it put to sea because of a lack of destroyers. The Germans were unable to base a large number of destroyers at Zeebrugge because of the risk of air attack, meaning that they face a lengthy canal journey from Bruges. This meant that the British normally detected their operations early, The Germans usually reinforced their Flanders Flotillas with extra destroyers from the High Seas Fleet before raids. [8]

The second, on 23 November 1916, was ineffectual. Six German destroyers approached the Downs and fired at the drifters, damaging one without causing any casualties, before turning away before the British destroyers in the area could engage them. They made no attempt to enter the Downs, where over 100 merchantmen were moored. The Germans claimed to have bombarded Ramsgate, but no shells landed on land.[9]

On 25-26 February 1917 the Germans sent destroyers to attack the traffic rout from England to the Hook of Holland, the Downs and the barrage. The only effects of this raid were that the destroyer HMS Laverock was struck by a torpedo that did not explode and that a bombardment the Thanet coast slightly damaged some houses.[10]

A German raid on 17-18 March resulted in the sinking of the destroyer HMS Paragon and the merchant ship SS Greypoint and the damaging of the destroyer HMS Llewellyn.

The next attack came on 20-21 April 1917. It was the first to end in a major German defeat. The destroyers SMS G42 and G85 were sunk by the British flotilla leaders HMS Broke and Swift.

This was a loss of almost 10 per cent of the destroyers based in Flanders and could not be replaced. The Germans therefore changed their strategy. Future attacks would be aimed at the Netherlands to UK convoys rather than the Channel patrols and barrage. Raids on shipping at the mouth of the Thames on 26 and 30 April encountered no shipping, although Margate was bombarded on 26 April. [11]

On 10 May a planned attack on Netherlands to UK convoys led to a battle between German destroyers and three British light cruisers and four destroyers., Neither side suffered any losses, but the British achieved their objective of protecting the convoy.[12]

A week later the Germans attacked a convoy in fog, sinking the merchantman SS Ciro. The British destroyer HMS Setter also sank after collided with HMS Sylph.[13]

A further raid on 23 May was unsuccessful. Three days later a raiding force encountered two monitors and two French torpedo boats, but a fifteen minute gun battle caused no losses to either side.[14]

The German surface forces in Flanders remained on the defensive for the remainder of 1917, fearing that the British might try an amphibious attack as part of their Passchendaele offensive. The British planned such an operation, but the land offensive did not go well enough for it to be carried out. The main tasks of the Flanders Flotillas in the rest of 1917 were minesweeping and coastal patrols. The British carried out a number of coastal bombardments, which were normally accompanied by major air battles, as both sides attempted to drive off the enemy’s observation aircraft. There were some naval encounters, but none resulted in losses to either side. By the end of 1917 too many vessels had been transferred away from Flanders, mainly to take part in Operation Albion, an amphibious assault in the Baltic Sea, for them to carry out offensive operations.[15]

Keyes takes Command

By late 1917 the Admiralty was concerned that up to 30 U-boats a month were evading the barrage. Rear Admiral Roger Keyes in December 1917, the Admiralty’s Director of Plans, proposed illuminating the mine and net barrage with searchlights at night in order to force U-boats to dive into the minefield. Bacon argued that this would reveal the barrage and make it vulnerable to attack. On 18 December he was ordered to institute an illuminated patrol. The next night UB56 was forced to dive and was destroyed by mines. Admiral Sir John Jellicoe, the First Sea Lord, was a supporter of Bacon, but he was dismissed and replaced by Admiral Sir Rosslyn Wemyss in late December. Soon afterwards, Bacon was replaced by Keyes.

Keyes strengthened the minefields and employed a patrol of a monitor with a 12 or 15 inch gun, four 30 knot destroyers, patrol boats, 14 trawlers, 60 drifters, four motor launches and two paddle minesweepers. At night the minefield was illuminated by flares from the trawlers and the destroyers’ searchlights.[16]

The larger U-boats stopped using the Straits in February and the smaller boats based in Flanders became less active from April. They laid 404 minefields in 1917 but only 64 in 1918. A 1922 Admiralty document claims seven U-boats sunk in the Dover Straits area in the first four months of 1918 and six in the rest of the year, 12 of them being UB or UC type boats.[17]

Uboat.net lists five boats lost to mines and one to depth charges in the Dover area in the first four months of the year, with the seventh described as missing. It gives four lost to mines in the Dover area and one off Flanders in the rest of the year, with the final boat having been rammed by the steamer Queen Alexandra off Cherbourg.

The Germans bombarded Yarmouth on the evening of 14 January 1918. They did not encounter any British warships and the only German ships damaged was the torpedo boat SMS V67, which struck a mine and had to be towed back to port. No ships on either side were sunk in minor actions on 23 January and 5 February.[18]

The last and seventh German raid on the Dover Barrage came on 14-15 February 1918. It was the most successful, sinking seven drifters and a trawler and severely damaging five drifters, a trawler and a paddle minesweeper without loss. Six of the raids had been successful, but they were at least a month and as much as nine months apart, with the result that the losses from one attack had always been replaced by the time of the next one. The Dover Straits Barrage therefore continued to keep U-boats out of the busy shipping lane of the English Channel, and to force them to sail round the British Isles on their way to the Atlantic, reducing their time on station. It is unclear why the Germans stopped attacking the Dover Barrage, especially when their last effort was so successful.[19]

The Dover Patrol took part in the attacks on Ostend and Zeebrugge on 23 April 1918, for which eight VCs were awarded, and the follow-up raid on Ostend on 9 May 1918, for which another three VCs were awarded. These raids were intended to close the canals that connected the ports of Zeebrugge and Ostend to the German naval base at Bruges. The first raid closed the Zeebrugge canal to larger destroyers until 14 May, but smaller torpedo boats and U-boats were able to use it and both raids failed to block the Ostend canal.

In 1918 the British launched a series of aerial bombing raids on the German naval bases in Flanders. From 17 February to 1 April five destroyers and torpedo boats and a U-boats were damaged by bombing. The Germans were forced to reinforce their fighter defences, but the raids became heavier from 10 May. Between then and 2 June 12 destroyers and torpedo boats and two U-boats were damaged by bombing. On the night of 28 May the Zeebrugge canal lock gate was hit by a bomb, putting it out of action for a week. On 9 June it was damaged by a coastal bombardment, closing the canal for the rest of the month to all shipping.[20]

The English Channel, a vital communications link for British troops in France and Flanders, remained open to Allied shipping throughout the war. By April 1918 it was largely closed to U-boats.

[1] Naval Staff Monograph (Historical) 1922 vol. vi, The Dover Patrol i, pp. 5-7.

[2] J. S. Corbett, H. Newbolt, Naval Operations, 5 vols (London: HMSO, 1938). vol. i, p. 16

[3] Naval Staff vol. vi, pp. 8-9.

[4] R. H. S. Bacon, The Dover Patrol, 1915-1917, 2 vols (London,: 1919). vol. i, pp. xii-xiv.

[5] L. Sondhaus, German Submarine Warfare in World War I: The Onset of Total War at Sea (Boulder MD: Rowman & Littlefield, 2017). Kindle Edition, locations 1902-50.

[6] M. Faulkner, A. D. Lambert, The Great War at Sea: A Naval Atlas 1914-1919 (Barnsley: Seaforth, 2015).

[7] Ibid., p. 105.

[8] Corbett, Newbolt, Naval. vol iv, pp. 66-67; P. G. Halpern, A Naval History of World War I (London: UCL Press, 1994), pp. 346-47.

[9] Naval Staff vol. vi, p. 88.

[10] Ibid., pp. 88-91.

[11] M. D. Karau, The Naval Flank of the Western Front: The German Marinekorps Flandern, 1914-1918 (Barnsley: Seaforth, 2003), p. 126.

[12] Ibid.

[13] Naval Staff Monograph (Historical) 1939 vol. xix, Home Waters part ix, May to July 1917, pp. 10-12.

[14] Karau, Naval, p. 126.

[15] Ibid., pp. 161-65.

[16] Corbett, Newbolt, Naval. vol. v, p. 309.

[17] Naval Staff vol. vi, p. 136.

[18] Karau, Naval, pp. 174-75.

[19] Corbett, Newbolt, Naval. vol. v. p. 217; Karau, Naval, p. 179.

[20] Karau, Naval, pp. 207-10.

3 Comments

Filed under War History

The Final Sortie of the High Seas Fleet

The final sortie of the German High Seas Fleet during the First World War took place between 22 and 25 April 1918. This was its first mission into the North Sea since August 1916, but it had not been inactive in the intervening period. From 10 to 20 October 1917 it had conducted Operation Albion, a major amphibious operation that resulted in the Germans capturing the Baltic islands of Ösel, Dago and Moon from the Russians.

Admiral Reinhard Scheer, C.-in-C. of the High Seas Fleet, learnt from U-boats that convoys between Norway and Great Britain had been escorted by battleships and battle cruisers since two German cruisers successfully attacked one on 17 October 1917. Scheer later wrote that:

‘A successful attack on such a convoy would not only result in the sinking of much tonnage, but would be a great military success, and would bring welcome relief to the U-boats operating in the Channel and round England, for it would force the English to send more warships to the northern waters.’[1]

Vizeadmiral Franz von Hipper’s battle cruisers (1st Scouting Group), the light cruisers of the 2nd Scouting Group and a destroyer flotilla would attack the convoy. All other available ships of the High Seas Fleet would cover the operations: the flagship, three battle squadrons less SMS Markgraf, the light cruisers of the 4th Scouting Group less SMS Stralsund and four destroyer flotillas.[2]

The Germans sailed at 5:00 am on 23 April but encountered fog at 10:30 am, when they were about to pass through the British minefields in the Helgoland Bight. It lifted after half an hour and they were able to proceed safely.[3]

The British then had four submarines patrolling the entrances to the Bight. HMS J6 spotted the German destroyers and light cruisers at 8:00 pm on 23 April, battle cruisers and destroyers at 8:30 pm and heavy ships at 00:15 am on 24 April. However, her captain had been told that British cruisers might be operating inside the area that he was patrolling, so assumed that they were British and did not report them.[4]

The Germans believed that the convoys travelled mainly at the start and middle of the week, so set the operation for Wednesday 24 April. In fact they sailed every four days, weather permitting. The limited range of most of the German destroyers and some of the light cruisers meant that they could stay in the operational area for only one day.[5]

A British convoy of 34 merchant ships had left Selbjorns Fjord at 1:15 pm on 22 April. Its close escort was only an armed boarding steamer and two destroyers, but it was being covered by the 2nd Battle cruiser Squadron and the 7th Light Cruiser Squadron to the south. It encountered heavy fog but reached Methil in the Firth of Forth on schedule on the morning of 24 April. The convoy to Norway was due to depart Methil the same day, with the result that the Germans would not have encountered any convoys even if their operation went to plan.[6]

The German operation did not go to plan. Early on 24 April the battle cruiser SMS Moltke suffered an engine breakdown, which reduced her speed to 13 knots. At 5:00 am Hipper ordered her to retire to the main German force. At 7:00 am Moltke was forced to break radio silence to report to Scheer that she was now capable of only 4 knots. Hipper at first turned back to help her but was then ordered by Scheer to resume his original course. Moltke was taken in tow by the battleship SMS Oldenburg at 10:45 am. Hipper did not spot any convoys and the main force set out back to base at 10 knots. Scheer had a choice of two routes and decided to take the quicker and more direct one. This increased the risk of encountering the British Grand Fleet but the other route, through the Kattegat was harder for Moltke and Oldenburg. It also risked offending the Danes and provoking the British into mining it, which would be bad for the U-boats.[7]

The British radio direction finding stations picked up the German signals and located them. At 11:45 am the Grand Fleet, which had been based at Rosyth in the Firth of Forth since 12 April, was ordered to put to sea. By the early afternoon 31 battleships, four of them American, four battle cruisers, two armoured cruisers, 24 light cruisers and 85 destroyers were at sea. Admiral Sir David Beatty, C.-in-C. of the Grand Fleet, was given the option of holding back the Methil to Norway convoy and adding the 2nd Battle Cruiser Squadron to his force but chose not to. Two battleships and the 2nd Cruiser Squadron were sent to join the force covering the convoy.[8]

At 4:00 am on 25 April J6 saw German light cruisers and destroyers and 90 minutes later spotted battlecruisers. They had passed by 7:15 am and she then reported them. Another British submarine, E42, had been sent to intercept the Germans and got into position early because they were moving slowly. At about 5:30 pm her captain Lieutenant C. H. Allen fired four torpedoes at a line of ships that was passing him. He then dived his boat and took an hour to lose the enemy, during which time he counted 25 explosions nearby.[9]

E42 had hit the port engine room of Moltke, but she made port. At 1:41 pm the Admiralty authorised Beatty to return to port if he wished.[10]

The German operation was well planned but failed because of faulty intelligence. Had the High Seas Fleet set off a day earlier or a day later it would have encountered a convoy and presumably overwhelmed it and its escort. Scheer seems to have relied upon U-boat commanders for intelligence. It is unclear if he asked German Consuls in neutral Norway for details of convoy movements. It is also uncertain if he knew whether or not the Grand Fleet was now based at Rosyth.[11]

Scheer went further north than ever before at a time when the enemy was further south. In the event the High Seas Fleet was able to avoid the Grand Fleet, but this might not have happened if J6 had reported the High Seas Fleet after spotting it several hours before it was detected by radio direction finding. Both sides could therefore point to missed opportunities.

 

[1] R. Scheer, Germany’s High Sea Fleet in the World War (London: Cassell and Company, 1920), p. 318.

[2] A. J. Marder, From the Dreadnought to Scapa Flow; the Royal Navy in the Fisher Era, 1904-1919, 5 vols (London: Oxford University Press, 1961-70), p. 149.

[3] Scheer, Germany’s, pp. 320-21. Times from this source have been adjusted for consistency with British sources, which quote times one hour behind German time.

[4] J. S. Corbett, H. Newbolt, Naval Operations, 5 vols (London: HMSO, 1938). vol. v, p. 284.

[5] Marder, From. vol. v, pp. 148-49.

[6] Corbett, Newbolt, Naval. vol. v, pp. 233-35.

[7] Scheer, Germany’s, pp. 321-22.

[8] Corbett, Newbolt, Naval. vol. v, pp. 232, 235-36.

[9] Ibid., p. 238.

[10] Marder, From. vol. v, p.154.

[11] Corbett, Newbolt, Naval. vol. v, ppp. 232, 238-39.

1 Comment

Filed under War History

The Zeebrugge Raid 23 April 1918

On 23 April 1918 the British raided Zeebrugge and Ostend with the intention of blocking the entrances to the canals linking the German destroyer and U-boat base at Bruges to the sea. These bases had been bombarded a number of times since August 1915.[1]

Approaches from Ostend and Zeebrugge to Bruges Docks. Source: https://en.wikipedia.org/wiki/Zeebrugge_Raid

Vice Admiral Roger Keyes succeeded Vice Admiral Sir Reginald Bacon in command at Dover on 1 January 1918. Keyes had in his previous job as the Admiralty’s Director of Plans prepared a plan to block Ostend and Zeebrugge. Bacon had made several changes to the plan. Keyes dropped Bacon’s intention of destroying the lock gates as well as blocking the locks, as he thought that this was impracticable. He retained his predecessor’s idea of landing on the mole at Zeebrugge in order to capture guns that threatened the approach of the blockships and to provide a diversion. This meant that a battalion of marines was needed as well as sailors.[2]

The old armoured cruiser HMS Vindictive (Captain Alfred Carpenter) would carry the first wave of the Zeebrugge assault force. Her armament, apart from two 6 inch guns on each side of the upper deck was removed and replaced with weapons more useful in an opposed landing: an 11 inch and two 7.5 inch howitzers; two flamethrowers; five pom-poms; 16 Lewis machine guns; and 16 Stokes mortars. The rest of the troops would be carried by two Mersey ferries, Iris (Commander V. Gibbs) and Daffodil (Lieutenant H. G. Campbell), which had double hulls and double bottoms, making them hard to sink, and had a shallow draft, enabling them to steam over minefields. However, it also meant that their decks were low, so they needed 30 foot scaling ladders to reach the parapet of the mole. The three assault ships were all fitted with grappling hooks to secure themselves to the mole.

Five old unarmoured cruisers were chosen to be the blockships: HMS Thetis (Commander R. S. Sneyd), Intrepid (Lieutenant S. S. Bonham-Carter) and Iphigenia for Zeebrugge; and HMS Sirius and Brilliant for Ostend. They carried minimal crews but kept some guns in order to fire as they approached and were fitted with extra steering positions to prevent a single hit disabling them. They were filled with cement to make it harder to move them and fitted with explosive charges to blow out their bottoms and sink them in the locks, with firing positions both fore and aft. Two C-class submarines, C1 (Lieutenant A. C. Newbold) and C3 (Lieutenant R. D. Sandford), were to destroy the viaduct that connected the Zeebrugge mole to the shore by exploding charges stowed in their bows.[3]

The attack would be covered by a smoke screen. Existing phosphorus based ones made dense but also created flames that were a beacon at night. Keyes therefore got Wing Commander Frank Brock, a former Royal Naval Air Service officer now serving with the newly formed Royal Air Force, to devise a substitute. Brock, a member of the family that founded and then still owned Brock’s, a large fireworks company, used chlor-sulphonic acid to produce dense smoke without flames. It was also used in saxin, a synthetic substitute for sugar, and 82 tons were needed. There was only one British manufacturer, so tea drinkers who used sugar substitutes had to drink unsweetened tea in order to provide enough chlor-sulphonic acid.[4]

The German coastal defences were formidable. There were also anti-aircraft batteries, including two guns on the mole. The numbers below are British estimates, which according to Mark Karau underestimate the actual numbers. However, the British estimate of 38 U-boats and 28 torpedo boats at Bruges and 30 destroyers at Zeebrugge was too high.[5]

 

Size Ostend Zeebrugge Zeebrugge Mole
Star shell howitzer 1
3.5 inch (88 mm) 4 2
4.1 inch (104 mm) 5 4 3
5.9 inch (150 mm) 15 7
6.7 inch (170 mm) 4
8.2 inch (208 mm) 4
11 inch (280 mm) 12 8
15 inch (380 mm) 4

Source: Corbett, J. S., Newbolt, H., Naval Operations. 5 vols (London: HMSO, 1938), vo. v, pp.246-47.

A 580 yard long railway viaduct, just wide enough to carry the railway, connected the shore to the Zeebrugge mole. The mole curved to the north east. It was 1,850 yards long and 80 yards wide and made of masonry. There was a 16 foot tall parapet on the western (seaward) side. A narrow masonry extension 260 yards long ended with a lighthouse. The mole batteries were on the extension, with an unimpeded arc of fire on any vessels approaching. the anti-aircraft guns were in a wired position 150 yards from the end of the mole, with a trench running across the mole. The gun crews and the mole’s 1,000 man garrison were housed in reinforced concrete sheds. There was a seaplane base at the south west end of the mole, which had its own garrison and concrete sheds.[6]

The British took advice from Belgian engineers, including two men who had recently escaped and had worked on a Zeebrugge dredger during the occupation, about the best places to position the block ships. The attack was to be preceded by aerial bombing and then an hour long bombardment of Ostend by seven monitors and Zeebrugge by two monitors. Similar attacks were made in the weeks before the operation to make this seem like a routine operations.[7]

A total of 165 vessels, 82 officers and 1,698 marines and seamen took part in the operation. As well as the assault and block ships, the monitors and numerous smaller craft, 29 destroyers would participate, with seven light cruisers, two flotilla leaders and 14 destroyers of the Harwich Force covering in case German ships tried to intervene from the north east. It was not an entirely British operation, as the French contributed seven torpedo boats and four motor launches.[8]

Keyes insisted that the men on the block ships and submarines should all be volunteers and unmarried. He said that the other participants were taking no greater risks than the infantry on the Western Front, but in practice the number of men keen to take part was far more than the number needed.[9]

Keyes originally intended to command from HMS Vindictive, but then realised that he needed to be able to move around to ensure that the various parts of the operation were going well. He therefore transferred his flag to the destroyer HMS Warwick.[10]

The force sailed on 11 April. While it was en route the RAF bombed Zeebrugge. At 00:45 am the expedition stopped in order to remove from the block ships the men needed for the passage but not the assault. Before it could get underway again the wind stopped and then began to blow from the wrong direction for the smoke screens. Keyes decided that it was impossible to attack without a smoke screen and called off the mission. Coastal Motor Boat 33 was captured by the Germans, who found plans on board that revealed that a blocking expedition at Ostend was planned.[11]

Another attempt was made on 13 April, but it had to be called off because the wind was too strong. There would not be another period when there was sufficient darkness and high water for three weeks. The Admiralty was inclined to cancel the operation on the grounds that surprise had been lost and the men could not be kept cooped up for so long. Keyes, however, persuaded them to let him try again between 22 and 28 April, when the high water was suitable. However, there was a full moon on 26 April.[12]

The assault troops had been accommodated on the pre-dreadnought battleship HMS Hindustan in port, but she was very crowded. Keyes arranged for HMS Dominion, another old battleship, to be sent in order to improve the living conditions ahead of the second attempt.[13]

The weather forecast on 22 April was favourable, with strength and direction of the wind being suitable and a good chance of clouds to obscure the moon. The expedition therefore set sail that day, with the attack to take place in the early hours of 23 April: St George’s Day.[14]

The aerial attack had to be cancelled because of rain, but the monitors started to bombard Ostend at 11:10 pm and Zeebrugge 20 minutes later. Coastal motor boats began to lay smoke screens at 11:30 pm and attacked the western end of the Zeebrugge mole in order to distract the Germans from the approaching Vindictive. Keyes had HMS Warwick positioned so that he could see both the attack on the mole and the approach of the block ships.[15]

 

Zeebrugge Raid 23 April 1918. Source: https://en.wikipedia.org/wiki/Zeebrugge_Raid

The Germans did not realise what was happening until the last minute, but then benefitted from a change in the wind. The smokescreen was blown across the approach routes, meaning that British vessels could not see each other, but the Germans could see them as they emerged from the smoke. Vindictive emerged just after midnight, coming under heavy fire. She suffered heavy casualties and many of her guns were put out of action. Captain H. C. Halahan, commander of the naval landing parties, Lieutenant-Colonel B. H. Elliot, commander of the Royal Marine landing parties and Major A. A. Cordner, his second in command, were all killed.[16]

Vindictive, Iris and Daffodil managed to get alongside the mole, a considerable feat of seamanship. Anchoring was very difficult. The surviving landing parties managed to get onto the mole under heavy fire. They could not destroy the mole’s guns, but the attack on the mole succeeded as a diversion. The Germans saw the block ships entering the harbour but probably assumed that the attack on the mole was the first stage in a landing.[17]

The towline of C1, one of the two submarines that were to be blown up against the rail viaduct connecting the mole to the shore, parted, meaning that only C3 reached the start line. Her crew were meant to abandon ship after setting her on a course for the viaduct, but her captain Sandford decided to ram the viaduct with the crew still on board and then light the fuses. They then took to a motor skiff that they had to row because of damage to its engine. They were just clear when the explosives blew up and destroyed 100 feet of the viaduct, including the telephone wires connecting the defenders of the mole to the German headquarters, They were then firing on HMS Thetis, the first of the block ships.[18]

Thetis was badly damaged and then was fouled by nets that had been laid across the harbour. She was unable to proceed to her target lock gates and ran aground before detonating her explosive charges. She had, however, cleared the way for Intrepid and Iphegenia to reach their target, where they grounded and blew themselves up. Motor launches took off the crews of the block ships. The British then withdrew, but the destroyer HMS North Star was sunk by the battery at the head of the mole. The destroyer HMS Phoebe took most of her crew off. Vindictive, Iris and Daffodil managed to withdraw, covered by Keyes’s flagship Warwick.[19]

The attempt to block Ostend failed, however. The shift in the wind had a more serious effect there. The Stroom Bank buoy had been moved a mile east of the position that the British expected it to be in. the block ship captains could not be sure of their positions because of the smoke blowing towards them. When they sighted the Stroom Bank buoy they did not realise that it had been moved, steered on a course based on it being in its previous position and sank their ships in the wrong place.

The British lost two motor launches and HMS North Star plus the block ships and submarines deliberately sacrificed. They reported 70 dead, 400 wounded and 45 missing. I counted 199 listed on naval-history.net as dying at Zeebrugge on 23 April and 16 of dying of wounds during the next week, but there are probably others who later died of wounds. Wikipedia, sourcing P. Kendall, The Zeebrugge Raid 1918: The Finest Feat of Arms (Brimscombe Port: Spellmount, 2009), says that British casualties were 227 dead and 356 wounded. The Germans claimed that 214 British were killed, 383 wounded and 19 captured, themselves losing Germans lost eight dead and 16 wounded. The German destroyers V69 and S53 were lightly damaged and S63 heavily damaged but remained seaworthy.[20]

One of the German dead was Matrose [Seaman] Hermann Künne, who had previously killed a British officer, probably Brock, in a cutlass fight.

The success at Zeebrugge and failure at Ostend led Keyes to propose another attack on Ostend. This was approved, but the British could not be ready to carry it out until the next period of favourable tides, which began on 9 May.[21]

The Zeebrugge canal was left unusable at low tide. Admiral Ludwig von Schröder, the local German commander, feared at first that it would also be blocked at high tide, but four relatively small German torpedo boats though it on the evening on 24 April, with a U-boat following the next day. The larger destroyers would have to use the Ostend canal. By 14 May salvage work allowed them to use the Zeebrugge canal at high tide and a wooden walkway allowing foot and bicycle traffic to and from the mole was completed on 8 June,[22]

The raid was executed very gallantly but its main effect was to boost Allied morale at a time when their armies on the Western Front were retreating as a result of the German March Offensive. Flanders based U-boats had to travel round Scotland to reach the Atlantic because of the Dover Barrage, which the German attack of 14-15 February showed could be attacked by destroyers based in the Helgoland Bight without them having to go via Bruges. The Germans, however, chose not to repeat that successful operation. . Both sides were happy enough with the outcome of the Zeebrugge Raid to give their commander a high award: the oak leaves to the Pour le Merite, popularly known as the Blue Max, for von Schröder; and a knighthood for Keyes.

Eight men were awarded the VC: the citations. originally published in the London Gazette, are on naval-history.net. Four of the awards were made under Clause 13 of the Victoria Cross Warrant. It allows that in a case where a large number of members of a unit deserve the VC it should be awarded by ballot of their peers. In this case the officers and the other ranks of the crews of the assault ships and the naval landing parties and the officers and the other ranks of the marine landing parties each selected one of their number.

Six awards were announced in July 1918, all to survivors and including the four Clause 13 medals. The naval officers chose Carpenter and the naval other ranks Able Seaman Albert McKenzie. The marine officers voted for Captain Edward Bamford and the marine other ranks for Serjeant Norman Finch. The other two went to Sandford of C3 and Lieutenant Percy Dean, commanding Motor Launch 282, which picked up survivors of the block ship,

The award of posthumous VCs to Lieutenant Commander George Bradford, RN and Lieutenant Commander Arthur Harrison, RN, were announced in March 1919. Both had commanded landing parties.

Barrie Pitt’s book Zeebrugge: Eleven VCs before Breakfast also covers the 10 May attack on Ostend, in which another three VCs were awarded. It will be the subject of a later post.

 

[1] Naval Staff Monograph (Historical) 1922 vol. vi, The Dover Patrol i, pp. 25-50.

[2] J. S. Corbett, H. Newbolt, Naval Operations, 5 vols (London: HMSO, 1938). vol. v, -pp. 242-44.

[3] Ibid., p. 245; M. D. Karau, The Naval Flank of the Western Front: The German Marinekorps Flandern, 1914-1918 (Barnsley: Seaforth, 2003), p. 190.

[4] Corbett, Newbolt, Naval. vol. v, pp. 245-46.

[5] Karau, Naval, pp. 187-88.

[6] Corbett, Newbolt, Naval. vol. v, p. 247.

[7] Ibid., p. 249.

[8] Ibid., pp. 249-50.

[9] B. Pitt, Zeebrugge: Eleven Vcs before Breakfast (London: Cassell Military, 2003), p. 60.

[10] Ibid., p. 69.

[11] Corbett, Newbolt, Naval. vol. v. pp. 251-52.

[12] Pitt, Zeebrugge, p. 82.-81

[13] Ibid.

[14] Corbett, Newbolt, Naval. vol. v. pp. 252-53.

[15] Ibid., pp. 254-55.

[16] Ibid., p. 256.

[17] Ibid., pp. 256-60.

[18] Ibid., pp. 260-61.

[19] Ibid., pp. 261-64.

[20] Karau, Naval, p. 196.

[21] Ibid., p. 198.

[22] Ibid., pp. 200-3.

2 Comments

Filed under War History

German Attack on the Dover Straits 14-15 February 1918

The last German attack on the British anti-submarine barrage across the Dover Straits came on the night of 14-15 February 1918. The previous one on 20-21 April 1917 had resulted in the loss of two German torpedo boats and a clear British victory. The Germans then changed strategy, launching a number of attacks on shipping between the Netherlands and the UK, the largest of which took place on 10 May.

The Germans then sat on the defensive because they feared that the British Passchendaele offensive might include an amphibious assault. The British planned such an operation, but the land offensive did not go well enough for it to be carried out. By the end of 1917 too many vessels had been transferred away from Flanders, mainly to take part in Operation Albion, an amphibious assault in the Baltic Sea, for them to carry out offensive operations.[1]

The attack in mid February was carried out by Korvettenkapitän Heinecke’s 2nd Flotilla of the High Seas Fleet, which sailed from Heligoland Bight without stopping in Flanders in order to achieved surprise. Its eight torpedo boats were meant to sail on 13 February but were delayed a day by bad weather and then reduced to seven when one of them suffered condenser problems.[2]

Heinecke’s plan was to divide his force into two groups. He would lead one, which would attack patrols south of Dungeness and then the patrol line from Folkestone to the Varne Bank. The other, led by Kapitänleutnant Kolbe, would attack the patrols on the south side of the Channel.[3]

Weather conditions on the night of 14-15 February were ideal for a raid. The weather was fine but overcast, the sea was unusually calm for the time of year and visibility was variable, with patches of haze. The minefield was illuminated by flares and searchlights in order to detect surfaced U-boats, but this blinded the vessels burning them, produced smoke and potentially obscured warning lights and gun flashes.[4]

The British had a light cruiser and three destroyers in the Downs, two destroyers on the West Barrage Patrol, four destroyers on the East Barrage Patrol and two paddle minesweepers, a monitor, a destroyer, a Patrol boat, two French torpedo boats and 10 trawlers supporting the 58 drifters patrolling the deep minefield. There should have been a monitor with 12 or 15 inch guns on duty but none was available so the 7.5 inch gunned HMS M26 was on duty.[5]

Between 11:30 and midnight on 14 February the drifter Shipmates (Lieutenant W. Denson RNR) spotted a submarine and fired the appropriate warning signal of red and white lights. The submarine soon disappeared. Around 00:30 am two German destroyers fired on the paddle minesweeper HMS Newbury. She was set alight and was unable to fire the green warning signal for surface raiders. British ships that heard the gunfire assumed that it was British ships attacking the U-boat.[6]

Denson of the Shipmates saw the gun flashes and realised that a German destroyer attack was underway. Before he could report it, his drifter was caught in German searchlights and his division was under fire. Presumably fearing that his vessel might be captured, he threw his confidential books overboard. The Shipmates managed to escape but did not fire a warning signal as Denson had seen two or three signal rockets. He could not send a coded radio message as he no longer had any codebooks and he had been ordered not to send uncoded messages.[7]

The British failed to realise what was happening, assuming that gunfire was aimed at the U-boat spotted by the Shipmates and that any destroyers that they spotted were friendly. Even the captain of a British motor launch fired at by German destroyers assumed that they were British and had mistaken his vessel for a U-boat. The Germans sank seven drifters and a trawler and severely damaged five drifters, a trawler and a paddle minesweeper; 89 British officers and men were dead or missing. Vice Admiral Sir Roger Keyes, C.-in-C. Dover Command, was not certain of what had happened until nearly 3:00 am, by when the Germans were on the way home.[8]

The British held a Court of Inquiry, which highlighted the faults in the processes for challenging, reporting and signalling in the Dover Straits. Lieutenant Adam Ferguson, captain of the destroyer HMS Amazon, challenged an unknown ship three times, which he said was the normal procedure. He was then supposed to open fire but the ship was by then out of sight. Ferguson was Court-Martialed and severely reprimanded. He and his immediate superior, Commander Bernard of the destroyer HMS Termagant, were both relieved of their commands.[9]

Keyes subsequently issued new orders stating that ‘Suspicious vessels are to be regarded as enemy, unnecessary challenges are to be avoided.’ Offensive action should be taken against ships that did not immediately reply to challenges.[10]

This was the seventh and last German attack on the Dover Barrage. Six of them had been successful with only the raid of 20-21 April being a British victory. However, the attacks came at least a month and as much as nine months apart, with the result that the losses from one raid had always been replaced by the time of the next one. The Dover Straits Barrage therefore continued to keep U-boats out of the busy shipping lane of the English Channel, and to force them to sail round the British Isles on their  way to the Atlantic, reducing their time on station. It is unclear why the Germans stopped attacking the Dover Barrage, especially when their last effort was so successful.[11]

 

[1] M. D. Karau, The Naval Flank of the Western Front: The German Marinekorps Flandern, 1914-1918, pp. 161-65.

[2] Ibid., p. 176.

[3] Ibid.

[4] Naval Staff Monograph (Historical) 1922 vol. vi, The Dover Patrol i. p. 104.

[5] J. S. Corbett, H. Newbolt, Naval Operations, 5 vols. vol. v, pp. 210-11.

[6] Ibid., p. 212.

[7] Ibid., pp. 212-13.

[8] Ibid., p. 217.

[9] Ibid., p. 216; A. J. Marder, From the Dreadnought to Scapa Flow; the Royal Navy in the Fisher Era, 1904-1919, 5 vols. vol. v, p. 44.

[10] Marder, From, p. 45.

[11] Corbett, Newbolt, Naval, p. 217; Karau, Naval, p. 179.

3 Comments

Filed under War History

German Destroyer Raid of 10 May 1917

In late 1916 and early 1917 the German carried out a number of raids on shipping in the Dover area and the anti-submarine net barrage across the Dover straits. The first that resulted in a German defeat was on 20-21 April 1917 when the destroyers SMS G42 and G85 were sunk by the British flotilla leaders HMS Broke and Swift.

The level of loss from this mission was unsustainable so the Germans changed their strategy. Future attacks would be aimed at the Netherlands to UK convoys rather than the Channel patrols and barrage. Raids on shipping at the mouth of the Thames on 26 and 30 April encountered no shipping, although Margate was bombarded on 26 April. [1]

In the early hours of 10 May the eight destroyers (822-960 tons, three 10.5cm (4.1in) guns, six 50cm (19.7in) torpedo tubes, 33.5-34 knots) of Korvettenkapitän Kahle’s 3rd Flotilla and the four destroyers of the Zeebrugge 1st Half Flotilla put to sea with orders to attack a large convoy that was due to leave the Netherlands for Great Britain that evening. Another 12 destroyers were on reconnaissance missions: four of the Zeebrugge 2nd Half Flotilla to the west and eight of the Flanders Torpedo-boat Flotilla to the south west.[2]

That night there were 12 merchant steamers heading from Great Britain to the Netherlands, with 10 travelling the other way. Commodore Reginald Tyrwhitt, commanding the Harwich Force, was at sea in the C Class cruiser HMS Centaur (4,165 tons, five 6in (15.2cm), one 13 pounder (76.2mm) and two 3in AA (76mm) guns, two 21in torpedo tubes, 29 knots) accompanied by the similar but slightly older HMS Carysfort and Conquest (4,219 tons, two 6 in (15.2cm), eight 4in (10.2 cm),one 13 pounder (76.2m), two 3in AA (76mm) and four 3 pounder (47mm) guns, two 21in torpedo tubes, 28.5 knots) and four destroyers. Other British destroyers were escorting the convoys.[3]

Between 3:50 and 3:55 am the British spotted the Germans to the south west, 8 or 9 miles away. Tyrwhitt ordered his ships to head south at full speed in an attempt to cut them off from Zeebrugge. At 4:05 am the British opened fire at about 13,000 yards range. The Germans headed south, returning fire. The light was poor and visibility was made worse by a German smoke screen and the smoke from the British cruisers, but both sides managed to straddle enemy ships with their gunfire and the British believed that they scored hits.[4]

The British pursued, but their cruisers were slower than the destroyers. By 5:02 am the German destroyers were out of range of the cruisers. The British destroyers, who had taken some time to work up to full speed, continued the chase. At 5:15 am some of the Germans turned, apparently to engage HMS Stork (975 tons, three 4in (10.2cm) and one 2 pounder (40mm) guns, four 21in torpedo tubes, 29 knots), the leading British destroyer, but withdrew on spotting that more British destroyers had arrived. Tyrwhitt called off the chase at 5:33 am , by when Stork had come under fire from German shore batteries.[5]

Neither side suffered serious damage in this operation, but it was a British victory since they prevented the Germans from carrying out their mission.

[1] M. D. Karau, The Naval Flank of the Western Front : The German Marinekorps Flandern, 1914-1918, p. 126.

[2] Naval Staff Monograph (Historical) 1939 vol. xix, Home Waters part ix, May to July 1917. p. 5; R. Gray, Conway’s All the World’s Fighting Ships, 1906-1921, pp. 168-69; Karau, Naval, p. 126.

[3] Naval Staff vol. Xix. p. 4; Gray, Conway’s 1906-1921, pp. 56, 60.

[4] Naval Staff vol. Xix. p. 4.

[5] Ibid., p. 5; Gray, Conway’s 1906-1921, p. 81.

1 Comment

Filed under War History

German Attack on the Dover Straits 20-21 April 1917

Following the German attack of 17-18 March 1917 on the anti-submarine net barrage in the Dover Straits, the Admiralty told Vice Admiral Sir Reginald Bacon, C.-in-C. Dover, that his forces should be more concentrated on nights when enemy attack appeared to be likely. The night of 20 April appeared to be such a night, as it was there was a new moon the next day and high water was at 2230.[1]

The British had two flotilla leaders (large destroyers) on the western part of the barrage and four destroyers to the east. There was a light cruiser, a flotilla leader and three destroyers and a monitor protecting shipping in the Downs, off the east coast of Kent and six destroyers at Dover.[2]

The Germans had strengthened their destroyer force at Zeebrugge by transferring Korvettenkapitän Kahle’s 3rd Flotilla from the High Seas Fleet. The operation on 20-21 April was to be controlled by Kahle. He would not be at sea but instead would command from Bruges, where the Germans collected and deciphered intercepted British orders. According to the British Official History, two groups would again attack the net barrage, but this time there would be no raid on the Downs.[3]

The force on the Dover side of the straits consisted of six destroyers from the 3rd Flotilla (822-960 tons, three 10.5 cm (4.1 inch) guns, six 50 cm (19.7 inch) torpedo tubes, 33.5-34 knots). That on the Calais side comprised four from the Zeebrugge Flotilla and two from the 3rd (852-990 tons, three 105 cm guns, six 50 cm torpedo tubes, 32-34 knots).[4]

However, Mark Karau’s history of the German naval forces in Flanders during the First World War says, based on German archives, that the Calais force included only three destroyers, with the other three operating in the Downs.[5]

A bombardment of Calais started at 2310 and one of Dover at 2330. Little damage was done to either town but  the armed trawler Sabreur was damaged at Dover. British batteries returned fire but without hitting the enemy. However, the bombardment caused Bacon to keep his Dover destroyers in port until 2355, by when the Germans had gone.[6]

At 0038 on 21 April, the Dover raiders sighted the flotilla leaders HMS Broke (1,610 tons, six 4 inch and one 1.5 pounder (20mm) guns, two .303 inch MGs, four 21 inch torpedo tubes, 31 knots) and Swift (2,170 tons, one 6 inch and two 4 inch guns, two 18 inch torpedo tubes, 35 knots). Broke was named after Sir Philip Broke, a successful frigate captain from the War of 1812.[7]

Firing commenced at 0044. Swift, which was ahead of Broke, turned towards the German line with the intention of ramming one of the smaller German ships. She missed and was hit by several shells, but one of her torpedoes hit SMS G85. Swift then pursued the Germans as far as the barrage but then had to give up because a shell hole had caused flooding in one of her forward compartments.[8]

Broke also fired torpedoes and attempted to ram a German destroyer. She missed first time but struck SMS G42 with her second attempt. She took several minutes to extricate herself, during when she came under fire from two other German destroyers. She tried to pursue the Germans but was too badly damaged to keep up with them. She therefore returned to G42, which was sinking by the stern but fired on Broke, which replied until the German guns fell silent about 0120. Broke’s engines then broke down and she began to drift towards G42. Some other British destroyers then arrived and took Broke under tow.[9]

G42 and G85 both eventually sank. The British picked up about 100 survivors from crews of 87 and 85 respectively. British losses were 40 killed or wounded on Broke and one killed and four wounded on Swift. The British casualties are listed on Naval-History.net.[10]

The two British captains, Commander Ambrose Peck of Swift and Commander Edward Evans of Broke, were awarded the Distinguished Service Order and promoted to Captain. Evans became a national hero as ‘Evans of the Broke‘ and reached the rank of Admiral, serving in the 1940 Norwegian Campaign. He had previously been second in command of Captain Robert Scott’s ill fated 1911-13 Antarctic Expedition.

The losses from this operation caused a change in German strategy. Future attacks would be aimed at the Netherlands to UK convoys rather than the Channel patrols and barrage.[11]

 

 

[1] Naval Staff Monograph (Historical) 1922 vol. vi, The Dover Patrol i. p. 97.

[2] J. S. Corbett, H. Newbolt, Naval Operations, 5 vols. vol. iv, , pp. 373-74..

[3] Ibid. vol. iv, p. 372,

[4] Ibid. vol. iv, p. 378; R. Gray, Conway’s All the World’s Fighting Ships, 1906-1921, pp. 168-69.

[5] M. D. Karau, The Naval Flank of the Western Front : The German Marinekorps Flandern, 1914-1918, p. 124.

[6] Naval Staff vol. vi. p. 98; Corbett, Newbolt, Naval, p. 375; Karau, Naval, p. 125.

[7] Gray, Conway’s 1906-1921, pp. 73, 77-78; Karau, Naval, p. 125.Karau gives German times that were an hour ahead of British time. All times quoted have been adjusted to British time.

[8] Naval Staff vol. vi. p. 99; Karau, Naval, p. 125.

[9] Corbett, Newbolt, Naval. vol. iv, pp. 377-78.

[10] Ibid. vol. iv. p. 378; Gray, Conway’s 1906-1921, pp. 168-69.

[11] Karau, Naval, p. 126.

3 Comments

Filed under War History