Second Battle of Heligoland Bight

British minelaying The British used sea mining defensively to protect sea lanes and trade routes and offensively to impede the transit of German submarines and surface ships in the North Sea, the danger of which was illustrated on 17 October 1917 by the sortie of the German s and (the action off Lerwick) against the Scandinavian Convoy. (During 1917, six U-boats were sunk by British mines and in two years, the German minesweeping counter-effort suffered the loss about 28 destroyers and 70 minesweepers and other ships.) The Germans had been forced into minesweeping up to into the Heligoland Bight and in the southern Baltic Sea, covered by light cruisers and destroyers, with occasional distant support by battleships. After the action off Lerwick, several proposals for attacks on the German minesweepers and escorts were canvassed at the Admiralty. On 31 October, the British sent a large force of cruisers and destroyers into the Kattegat, which sank , an armed merchant ship and nine trawlers. German test trips The prolific British laying of mines and net barrages outside the main German mine belts between Horns Reef and Terschelling, close to the bases of the High Seas Fleet () forced the into surveying the British minefields, to find routes through them for transit into and back from the North Sea. Test trips were carried out, being substantial operations with ships to find the mines, minesweepers, torpedo boats (usually a continental term for destroyers), U-boats, barrier breakers and light cruisers, with air reconnaissance by Zeppelins and seaplanes. The Test trips were also protected by battleships on routes known to be free of mines. ==Prelude==

North Sea operations On 20 October, the British code breakers of Room 40, part of the Naval Intelligence Division of the Admiralty, decrypted orders to the submarine to scout to the north of Bergen to find the new route of the Scandinavian Convoy. Agent reports from Copenhagen disclosed an imminent German attack by seven light cruisers and 36 destroyers. During the week ending 11 November, British light cruisers, destroyers and a battlecruiser escort, conducted an abortive sweep along the fringe of the Heligoland Bight minefields. By mid-November the Admiralty had obtained enough intelligence to intercept one of the big German minesweeping operations, provided that the ships based at Rosyth, in Scotland, could sail in time. The Admiralty decided that an offensive operation should begin on 17 November. Test trip, 17 November The Germans planned a Test trip for 17 November 1917, comprising the 2nd and 6th Auxiliary Mine Sweeper Half-Flotillas, the 12th and 14th Torpedo Boat Half-Flotillas, Barrier Breaking Division IV and light cruisers of Scouting Group Division II, commanded by Rear-Admiral () Ludwig von Reuter from the 6th Mine Sweeper Half-Flotilla. The s and from Squadron IV, each with ten guns, led by Captain () Kurt Graßhoff in Kaiserin, were to act as covering force for the group. The battleships were to reach a point west of Heligoland by while the Test trip group rendezvoused in the Heligoland Bight about half-way between Horns Reef and Terschelling. With poor weather grounding Zeppelins and making it impossible for light cruisers to embark seaplanes after they had alighted on the sea, the Test trip relied on reconnaissance patrols by two land-based seaplanes from Borkum on the German coast just east of the Netherlands, for reconnoitring ahead of the group. British plan The German Test trip had been revealed by the code breakers of Room 40, allowing the British to plan an ambush. On 16 November, orders for an attack on the Test trip were sent to Admiral Sir David Beatty, Commander-in-Chief of the British Grand Fleet. On 17 November 1917 a force of cruisers under Vice Admiral Trevylyan Napier was sent to attack the German minesweepers as they were minesweeping. ==Battle==

The action began at roughly west of Sylt, when sighted German ships. She opened fire at Reuter advanced with four light cruisers and eight destroyers towards the British ship to cover the withdrawal of the minesweepers, with all but the trawler , escaping the British detachment. A stern chase ensued as the German forces, making skillful use of smokescreens, withdrew south-east at their best speed, under fire from the 1st Cruiser Squadron, the 1st Light Cruiser Squadron and the 6th Light Cruiser Squadron. was detached from the 1st Battle Cruiser Squadron and came up at high speed to join the battle. Both sides were hampered in their manoeuvres by the presence of naval minefields. At about the same time, the light cruisers came under fire from Kaiser and Kaiserin, Kaiser-class battleships, which had come up in support of Reuter's ships; was struck by a shell, which damaged a gun turret; shortly afterwards, the British ships gave up the chase as they reached the edge of more minefields. A shell went through the upper conning tower of the light cruiser , killing the conning tower crew and mortally wounding the Captain, Herbert Edwards, on the bridge and knocking unconscious the navigator, Lieutenant-Commander M. F. F. Wilson. All personnel on the lower bridge were killed and the gunnery officer, Lieutenant H. C. C. Clarke took command, which was made more difficult because the shell also cut all electrical communications and reduced the rate of fire. The battlecruiser Repulse briefly engaged the German ships at about achieving a hit on the light cruiser that started a serious fire. ==Aftermath==

Analysis In 1984, Patrick Beesly wrote that the British operation was daring but that Napier was unjustly blamed for its failure to pursue the German ships with sufficient vigour. Room 40 was well informed about the positions of German minefields and the British fields which the Germans were trying to clear. The information had been added to Room 40's naval charts but the information was denied to Napier, who made decisions based on the charts he did have. Admiralty reluctance to disclose that their information was derived from the decoding of wireless intercepts had led to the naval commander being ill-informed. The Admiralty did at least supply operational intelligence to the naval commanders, after Beatty had made an emergency request when he was at sea. Napier was informed in ninety minutes by the Admiralty that German capital ships had sailed at and the location of German cruisers, leading to Königsberg receiving severe damage. At the least, Room 40 had prevented the British operation degenerating from fiasco to disaster. Casualties In 1920, Admiral Reinhard Scheer wrote that the Germans suffered casualties of killed, ten seriously wounded and thirty men slightly wounded. An Admiralty communiqué listed British casualties as one officer and killed, four officers and wounded; were taken. Victoria Cross Able Seaman John Carless of Walsall, aboard Commodore Cowan's flagship Caledon, was awarded a posthumous Victoria Cross for his bravery in continuing to load and fire his gun despite receiving mortal shrapnel wounds that opened his abdomen. ==Orders of battle==

British forces 1st Cruiser Squadron Vice Admiral Trevylyan Napier CB, MVO : (flag; Capt Arthur Bromley) : (Capt Charles B. Miller CB) : Attached destroyers (13th Destroyer Flotilla) :: (Cdr John Tovey) :: (Lt. Cdr. Montague G. B. Legge DSO) :: (Lt Cdr Guy P. Bowles) :: (Lt Cdr Roger V. Alison DSO) 6th Light Cruiser Squadron Rear Admiral Edwyn Alexander-Sinclair CB MVO : (flag; Capt. Claud H. Sinclair) : (Capt. the Hon. Herbert Meade DSO) : (Capt. Herbert L. Edwards) : (Capt. William M. Kerr) : Attached destroyers (13th Destroyer Flotilla) :: (flotilla leader; Cdr. Charles A. Fremantle) :: (Cdr. Dashwood F. Moir) :: (Lt Cdr. Kenneth A. Beattie) :: (Lt. Vernon Hammersley-Heenan) 1st Light Cruiser Squadron Commodore Walter Cowan CB, MVO, DSO : (Cdre Cowan) : (Capt. Charles Forbes DSO) : (Capt. the Hon. Mathew R. Best MVO, DSO) : (Capt. Francis A. Marten) : Attached destroyers (13th Destroyer Flotilla) :: (Cdr. Charles Ramsey) :: (Lt. Cdr. Charles H. Neill James) 1st Battle Cruiser Squadron (detachment) Rear Admiral Richard Phillimore CB, MVO : (flag; Capt. William Boyle) Other forces at sea in support (none of which engaged) : Battle Cruiser Force : Vice Admiral Sir William Pakenham KCB, KCVO) :: (flag), , , :: Attached light forces (13th Destroyer Flotilla) ::: (flotilla cruiser), , , , , , , , . : 1st Battle Squadron : Admiral Sir Charles Madden :: (flag), , , , , :: Attached destroyers (12th Destroyer Flotilla) ::: (flotilla leader), (flotilla leader), , , , , , , , , . German forces 2nd Scouting Group Konteradmiral Ludwig von Reuter : (FKpt Karl Feldmann) : (FKpt Gerhard von Gaudecker) : (FKpt Otto Seidensticker) : (KptzS Walther Hildebrand) 7th Torpedo-Boat Flotilla KKpt Hermann Cordes : (KptLt Max Fink; flotilla leader) : (OLtzS Wolfgang Komorowski) : 14th half-flotilla (KptLt Richard Beitzen) :: (KptLt Arthur von Killinger; half-flotilla leader) :: (KptLt Georg Reimer) :: (Kpt Lt Wedig von Keyserlingk) : 12th half-flotilla (KKpt Rudolf Lahs) :: (OLtzS Victor Narjes; half-flotilla leader) :: (OLtzS Eberhard Kautter) :: (KptLt Martin Laßmann) Minesweepers : 6th Minesweeper Half-Flotilla [6. ] (KptLt d'Ottilié) :: M66, M7, A36, T74, M53, M4, M3, M1 : 4th Auxiliary Minesweeper Half-Flotilla [4. ] (KptLt d R Joachim Löwe) :: A63, A68, A69, A74, A41, A52 : 2nd Auxiliary Minesweeper Half-Flotilla (KptLt d R Klose) :: fishing vessels : 6th Auxiliary Minesweeper Half-Flotilla (KptLt d R Wilke) :: fishing vessels : 4th Barrier-Breaker Group [IV. ] (KptLt d R Hillebrand) :: two vessels : Group S, North Sea Outpost Flotilla (LtzS Heinrich Woldag)NO :: armed trawlers Fritz Reuter and KehdingenGE 4th Battle Squadron (detachment) KptzS Kurt Graßhoff : (KptzS Kurt Graßhoff) : (KptzS Max Loesch) : Attached torpedo-boats (anti-submarine escort) :: (KptLt Wildemann) :: (KptLt Paschen) Other forces at sea in support (none of which were engaged) : Battleships: , : Battlecruisers: , ==Notes==