Zeebrugge Raid
The Zeebrugge Raid (Dutch: Aanval op de haven van Zeebrugge; French: Raid sur Zeebruges) on 23 April 1918, was an attempt by the Royal Navy to block the Belgian port of Bruges-Zeebrugge. The British intended to sink obsolete ships in the canal entrance, to prevent German vessels from leaving port. The port was used by the Imperial German Navy as a base for U-boats and light shipping, which were a threat to Allied control of the English Channel and southern North Sea. Several attempts to close the Flanders ports by bombardment failed and Operation Hush, a 1917 plan to advance up the coast, proved abortive. As ship losses to U-boats increased, finding a way to close the ports became urgent and the Admiralty became more willing to consider a raid.
See also: First Ostend Raid and Second Ostend RaidAn attempt to raid Zeebrugge was made on 2 April 1918 but was cancelled at the last moment, after the wind direction changed and made it impossible to lay a smokescreen to cover the ships. Another attempt was made on 23 April, with a concurrent attack on Ostend. Two of three blockships were scuttled in the narrowest part of the Bruges–Ostend Canal and one of two submarines rammed the viaduct linking the shore and the mole, to trap the German garrison. The blockships were sunk in the wrong place and after a few days the Germans had opened the canal to submarines at high tide. Lessons were learned during the operation that would be put to use in the Second World War.
Background[edit]
Strategic developments[edit]
At the end of 1916 a combined operation against Borkum, Ostend and Zeebrugge had been considered by Admiral Sir Lewis Bayly, commander of the Coast of Ireland Station. The plan was rejected due to the difficulty of supplying a landing force and the vulnerability of such a force to a land counter-attack; subsequent proposals were rejected for the same reasons. A bombardment of the Zeebrugge lock gates under cover of a smoke screen was studied by Vice-Admiral Sir Reginald Bacon, commander of the Dover Patrol and the Admiralty in late 1915 but was also rejected as too risky. In 1916, Commodore Reginald Tyrwhitt proposed an attack to block Zeebrugge, which was rejected. Tyrwhitt suggested a more ambitious operation to capture the mole and the town as a prelude to advancing on Antwerp. Bacon was asked to give his opinion and rejected the plan, as did the Admiralty.[1]
Rear-Admiral Roger Keyes was appointed director of the Plans Division at the Admiralty in October 1917 and on 3 December submitted another plan for the blocking of Zeebrugge and Ostend using old cruisers in a night attack in the period from 14 to 19 March. Bacon also proposed an operation on 18 December, which combined Tyrwhitt's landing on the mole with a blocking operation. A monitor, HMS Sir John Moore, was to land 1,000 troops on the mole, the monitor HMS General Craufurd was to bombard the lock gates and fortifications from short range; the blockships were to enter the harbour in the confusion. The raid was proposed in 1917 by Admiral Sir John Jellicoe but was not authorised until Keyes adapted Bacon's plan for a blocking operation, to make it difficult for German ships and submarines to leave the port. The raid was approved in January 1918 and volunteer crews were obtained from the Grand Fleet "to perform a hazardous service".[2]
Prelude[edit]
German defences[edit]
By 1917 the German defences on the Flanders coast included Kaiser Wilhelm II, a heavy artillery battery at Knokke, east of the Bruges Canal, of four 12 in (300 mm) guns, with a range of 41,000 yd (23 mi; 37 km) and the Tirpitz battery of four 11 in (280 mm) guns, with a range of 35,000 yd (20 mi; 32 km), 1.5 mi (2.4 km) west of Ostend. Two more batteries were being built in early 1917 and between the main defences were many mobile guns, entrenchments and machine-gun nests. The only vulnerable part of the German defensive system was the lock gates at Zeebrugge, the destruction of which would make the canal to Bruges tidal and drastically reduce the number of ships and submarines that could pass along it.[15]
British preparations[edit]
An appeal was made to the Grand Fleet for volunteers for special service on 23 February 1918.[c] Very few of the participants were aware of the objective.[18][19][d] The cruisers involved in the blockade, including HMS Vindictive, were equipped in Chatham by over 2,000 workers for the special fitting out or (in the case of the ships to be sunk) stripping out of unnecessary equipment, including their masts. Iris, Daffodil and the submarines were converted in Portsmouth. The fleet made its rendezvous at Swin Deep, about 8 nmi (9.2 mi; 15 km) south of Clacton. The first opportunity for the raid was early April 1918 and on 2 April the fleet sailed and Zeebrugge was bombed by 65 Squadron from Dunkirk. The success of the raid depended upon smokescreens to protect the British ships from the fire of German coastal artillery but the wind direction was unfavourable and the attack was called off. Zeebrugge was visible to the fleet and the fleet to the Germans in Zeebrugge; seventy-seven ships of all sizes, some with their lights already switched off, had to make a sharp turn to the west to return to their bases.[21]
Royal Navy order of battle for the Zeebrugge and Ostend Raids: 22 April 1918[46]