A Naval History of World War I

by Paul G. Halpern

  What was the German response to these measures, and what about the vulnerability of the patrols burning lights? Keyes relied for protection on two destroyer patrols, one on the eastern half of the barrage and the other on the western half. The destroyers patrolled the area between the Folkestone and Cape Gris-Nez minefields and the old Goodwin Sands-Snouw Bank barrage. The latter was tacitly abandoned and allowed to deteriorate. The British also relied on receiving advance warning of a potential German raid through wireless intercepts and the work of Room 40.

  The serious attack on the new barrage came in mid-February. Marinekorps Flandern requested the High Sea Fleet destroy the new British light barrier in the Strait, which “made it very much more difficult” for the U-boats to get through unmolested and was “actually almost impassable.” The German forces in Flanders admitted they were unable “to deal a sufficiently effective blow” and asked the High Sea Fleet for assistance.18 Scheer sent the Second Flotilla under Korvettenkapitän Heinecke, who was to proceed to the attack directly from the German coast without calling at the Flanders base in order to achieve surprise. The destroyers were to refuel at Zeebrugge after the attack and immediately return to German waters.

  The operation was postponed once because of bad weather, but on 13 February Heinecke in B.97 sailed with the Third and Fourth Half-Flotillas, eight large (1,700–1,800 tons) and powerful destroyers, although one was forced to drop out and return to Germany with condenser trouble the following day. Shortly after midnight on the night of 14–15 February, the German force split in two northeast of Sandettie Bank. Heinecke in B.97 led the Fourth Half-Flotilla (B.109 and B.110, reinforced by V.100) in an attack on the barrage west of the Varne and Colbart Bank. Kapitänleutnant Kolbe in G.101 led the Third Half-Flotilla (G.102 and G.103) in an attack to the east of the bank. The Germans achieved complete surprise, aided by the very dark night and, perhaps, the fact that it was the first destroyer attack on the Dover Strait patrols since April of 1917. Also, the British patrols committed errors that helped the Germans escape. They had been alerted by NID that a German submarine would attempt to break through the barrage on its way home. This may have assisted the Germans when firing first broke out, as the patrols assumed it was the drifters engaging the submarine trying to break through on the surface.

  There were other serious lapses. The three destroyers of Kolbe’s group on their way home encountered the four destroyers of the eastern barrage patrol. The Amazon, the last ship in the British line, saw the Germans passing astern, challenged, and received no reply. Nevertheless, her commander concluded they were friendly and passed the message down the line of ships to the senior officer in the Termagant that three of their destroyers had passed. The senior officer asked how the Amazon knew they were friendly, but by the time the messages passed up and down the line and he learned the destroyers had not responded to the challenge, it was too late to act and the patrol continued as normal. Kolbe had not opened fire on the British because his force was slowed by condenser trouble in G. 103 and he erroneously believed the British patrol numbered six destroyers. The senior officer on the minefield patrol in the monitor M.26 also failed to promptly inform Keyes he had seen a green flare, the signal for “enemy surface craft,” as opposed to white and red flares, the signal for a submarine on the surface.

  The Germans got away unscathed, although G.102 was mined on the approaches to Zeebrugge and unable to return to Germany with the flotilla until repairs were completed a few days later. The German destroyers sank by gunfire a trawler and seven drifters and severely damaged another trawler, a paddle minesweeper, and five drifters. Scheer claimed they had sunk more than thirty ships and that a reconnaissance by one of the torpedo boats of Marinekorps Flandern the following day revealed “the guard had been completely withdrawn.” The German official history published in the 1960s repeated the claim that the following night the illumination of the Strait had been extinguished.19

  Keyes wrote Beatty, “The murder of those gallant fishermen has made me feel very b—y minded,” and called the German communique “a dirty lie” because the trawlers and drifters had gone out full strength the next night with “the usual number burning flares incessantly.”20 Keyes demanded action against those patrol officers who had let his command down. In the end the commander of the Amazon was court-martialed and sentenced to be severely reprimanded. Keyes considered this sentence excessively lenient. The officer was relieved of his command, as were the commanders of the Termagant and M.26. Keyes, for his part, rewrote the patrol orders to include the clear statements that suspicious vessels were to be regarded as enemy; excessive challenges were to be avoided; and if a challenge was not immediately answered, offensive action was to be taken without delay.21 None of this should obscure the fact that given the technology of the time, it probably would have been impossible to avoid some loss to the ships burning flares: they were easy targets. Unpleasant as it may have seemed, the occasional loss of trawlers and drifters on the barrage might have been the price of maintaining control of the Strait. Under the circumstances, the courage of the auxiliary patrol who manned the little ships is all the greater. It is also significant that this turned out to be the last destroyer raid on the Dover Strait during the war. The Germans could not permanently shake the barrage and, as we have seen, the barrage was steadily growing more effective.

  The German Flanders Flotilla did try to attack the Allied line of communications between Dunkirk and Nieuport where the railway line ran close to the sea. The attack on the night of 20–21 March by nine destroyers and six torpedo boats—with another four small A-class torpedo boats to mark the bombardment positions—coincided with the beginning of Ludendorff’s major offensive on the western front. After Russia dropped out of the war, the Germans were able to shift troops to the western front, and employing their numerical superiority, as well as innovative tactics, they began a great attack on 21 March. In very broad terms, the Ludendorff offensive was a desperate gamble to achieve a decision on the western front before the American army could arrive in force. The naval accompaniment was puny. The German flotilla was divided into three bombardment groups, but their raid achieved little. They were promptly engaged by the monitor Terror anchored off the coast, and the flotilla leader Botha, British destroyer Morris, and French destroyers Capitaine Mehl, Magon, and Bouclier immediately put to sea from Dunkirk. The running battle that followed had all the confusion usual in a night action of this sort. The torpedo boats A.19 and A.7, which had marked the positions through which the bombardment groups had to pass, were cut off, and the Botha, although slowed by damage from the guns of the German destroyers, managed to ram and sink A.19. Her fighting lights were, however, extinguished by damage to her electrical circuits. This led to a tragic mistake, for when the officer commanding the torpedo tubes in the Capitaine Mehl saw a large destroyer without fighting lights, he concluded she was German and fired a torpedo—striking the Botha in the after boiler room. In the meantime the French destroyers overwhelmed and sank A.7 and then screened the Morris, which towed the crippled Botha back to port. The Flanders Flotilla had lost a pair of ships with little to show for it, and, although they conducted a fleeting bombardment farther to the east in the vicinity of La Panne on 9 April, the Flanders Flotilla was as incapable of seriously disturbing the seaward flank of the Allied armies as the High Sea Fleet was of permanently disrupting the blockade in the Dover Strait.22

  THE ZEEBRUGGE AND OSTEND RAIDS

  Zeebrugge, Ostend, and Bruges formed a triangle with Bruges as its apex. The submarine pens at Bruges, protected by massive concrete shelters from aerial attack, were connected to Zeebrugge by an 8-mile canal. A series of smaller canals also led from Bruges to Ostend. The base of the triangle was formed by approximately 12 miles of heavily fortified coastline between Zeebrugge and Ostend. Zeebrugge was also the location of a particularly active German naval air station. The shelter given by the mole generally provided smooth water for seaplanes to take off within the harbor, and throu
ghout 1918 the Brandenburg W.12 and W.29 twin-float seaplanes—the W.29 a powerfully armed monoplane—earned considerable respect from their British opponents.

  The German destroyers and submarines at Bruges were invulnerable to attack from the sea. British monitors had bombarded Zeebrugge and Ostend from the sea in operations requiring elaborate preparations and careful screening as well as seldom-achieved conditions of weather and tide. Bacon had hoped to cut off Bruges by damaging the lock gates to the canal at Zeebrugge. The German defenses necessitated long-range indirect bombardment, which, as the official history put it, required “hitting an invisible target ninety feet long and thirty feet wide from a distance of about thirteen miles,” all the while under fire from the four 12-inch guns of the Kaiser Wilhelm II battery. The bombardments could not inflict permanent damage, and Bruges remained out of reach.23

  Keyes was determined to block Zeebrugge and Ostend from the moment he became commander of the Dover Patrol. He recognized the potential threat to the barrage that the Flanders Flotilla represented: “At present it is an awful strain on my flotilla to keep up this constant watch on the Z[eebrugge] destroyers who have so many and such easy objectives within a short steam.”24 The success of the Dover barrage and the blocking of Zeebrugge and Ostend were linked, and offensive action of this sort was completely in line with Keyes’s natural inclinations. Plans Division had studied the question well before Keyes replaced Bacon. The importance of Zeebrugge was evident. There had been separate proposals for an attack by others, including Bayly and Tyrwhitt in 1916 and 1917. Bacon too had elaborated various schemes, which Keyes and Plans Division dismissed as impracticable.25

  Keyes submitted the final plan for Operation Z.O. to the Admiralty on 24 February.26 By then preparations were well under way. The basic plan was to simultaneously sink blockships in the entrance to the Zeebrugge-Bruges canal and the entrance to Ostend harbor. The blockships would be obsolete cruisers: the Iphigenia, Intrepid, and Thetis for Zeebrugge; the Sirius and Brilliant for Ostend. The blockships at Zeebrugge would have to pass the massive curved stone mole—1,840 yards long, 80 yards wide, and connected to the shore by a 300-yard viaduct—which formed the harbor and then proceed more than 3,400 feet to the entrance of the canal. There were batteries at the northern extremity of the mole that threatened the blockships, and the raiding force would therefore have to storm and temporarily occupy the northern part of the mole to neutralize the danger. The mole would be attacked from the seaward side by approximately 700 Royal Marines and 200 seamen carried in the specially modified old cruiser Vindictive and Mersey ferries Daffodil and Iris II. The Vindictive was fitted with machine guns, mortars, flame throwers, one 11-inch and two 7.5-inch howitzers for engaging the shore batteries, ramps, and specially hinged brows that would be lowered onto the mole for landing troops. The ferries, which the Vindictive would have to tow to the approaches to Zeebrugge, would carry 22-foot scaling ladders because even at high water their decks would be well below the mole.

  The British planned to sacrifice CMBs—later altered to the obsolete submarines C.1 and C.3—to blow up the viaduct connecting the mole to the shore, thereby preventing German reinforcements from reaching the mole. The plan also called for the extensive use of smoke screens, and aerial attacks and long-range bombardments of the coastal batteries near Ostend and Zeebrugge by monitors would serve as diversions. The bombardments would begin, weather permitting, in the weeks preceding the operation in order to lull the Germans into the belief they were routine. The crews of the blockships would abandon ship in boats and rafts and would be picked up by motor launches and CMBs. A grand total of 165 vessels of all types and 82 officers and 1,698 seamen and marines were allocated to the operation. Keyes flew his flag in the destroyer Warwick.27 Many of the men had been specially picked from the Grand Fleet. There would have been no lack of volunteers: for many Operation Z.O. seemed to end a long period of frustration. At last the navy was really going to do something. Again, Keyes probably expressed the typical sentiment when he wrote Beatty: “The more I think of it the more confident I feel that—even if we don’t absolutely achieve all we are setting to do—we will accomplish a good deal for the credit of the Service, and will give the enemy a bad night.”28

  The operation was originally scheduled to take place during the period in March when tide and moon conditions were right, but had to be postponed when the necessary amount of the essential smoke making chemicals could not be produced in time and the late arrival of some of the ships delayed their conversion. The expedition sailed the night of 11 April but when only about 16 miles from their objective Keyes discovered the wind had dropped to nothing and then shifted so that it was blowing from the south. This would have deprived the British of the benefits of the smoke screen and exposed the force to possible disaster. Keyes had no choice but to abort the operation and execute the far from easy task of turning the force about and returning to port. The feelings of all, especially keyed up for the operation, can only be imagined. The operation was canceled again on the 13th after the vessels had already raised steam because the wind had risen to the point where the sea was too rough for the small craft to operate or the boarding vessels to berth on the seaward side of the mole. The British now had to wait in great suspense for the next period of favorable conditions of tide and moon.29

  The tidal conditions were right for the operation to take place the night of 22–23 April, although the moon itself was full. Keyes elected to take the risk rather than wait for the next dark period the following month. The date may have been auspicious; the 23d was St. George’s Day—the patron saint of England. As dusk fell, Keyes made the general signal to the force: “St. George for England” and Captain Carpenter, commanding the Vindictive, replied: “May we give the dragon’s tail a damned good twist.” The Zeebrugge operation might well have ended in disaster, given the scale of German defenses and the implacable conditions of modern warfare, which seemed to put a premium on firepower over human courage. Furthermore, the Germans were forewarned. During the aborted attempt on the night of 11–12 April, a CMB had run aground off Zeebrugge and the Germans recovered an order with plans for the operation. They apparently acted in only the most desultory manner on the information with a general order for a higher degree of alert to some, but not the most important, sectors of the coast defense.30

  The Germans reacted to the approach of the British about ten minutes before the Vindictive was due to reach the mole. Unfortunately, the British smoke screen here was rendered ineffective by a shift in the wind and the destruction of many of the smoke floats by German gunfire. The old cruiser was exposed to the German gunners in the light of star shells and searchlights. The Vindictive’s upper works were swept by heavy fire in the last 200 yards of her approach and casualties were heavy. The commander and second in command of the marine landing party were killed, along with the commander of the seamen landing party. Carpenter increased speed, but the final surge brought the Vindictive more than 340 yards farther along the mole than had been intended. This had unfortunate consequences, for it meant the guns at the end of the mole—her original objective—were too far for the landing parties to reach, her guns could not bear on the troops defending them, and she was now exposed to fire from shore batteries to the west of the mole. Other things went wrong. The special grapples with which she was equipped to anchor her to the mole failed to grip, and it required the Daffodil to push her against the mole before the special brows for landing troops could be dropped. By this time, only two—later increased to four—were serviceable. The Daffodil was forced to keep pinning the cruiser to the mole for the full fifty-five minutes the landing parties were on shore. The Iris was not able to anchor to the mole and had finally gone alongside the Vindictive’s starboard quarter to disembark her troops only to have the recall sounded.

  The landing parties performed prodigious feats of valor, but they did not get very far, and it was physically impossible for them to reach the crucial guns on the mole extension,
which were covered by machine guns. The Vindictive’s 11-inch howitzer was able to engage shore batteries, but one of the 7.5-inch guns was knocked out and the other never opened fire—two successive crews were killed by shell fire. Carpenter ordered the recall to be sounded once the blockships had been seen passing into the harbor. It seemed something of a miracle that any of the landing party could be reembarked and that the Vindictive, Iris, and Daffodil could get away without being sunk. The British were more successful at the viaduct. Although C.1 had parted her tow and failed to arrive before the recall, C.3 reached the viaduct and lodged between two piers. Her crew after setting the fuses escaped in a skiff under heavy fire. The explosion cut the viaduct.

  What of the blockships themselves? The heavy fighting on the mole combined with smoke may have enabled the three blockships to approach and escape detection until they were almost on top of the batteries at the extension of the mole. They were then subjected to virtually point-blank fire, but the Germans seemed to concentrate on the Thetis, the lead ship. The Thetis was riddled but managed to break through the net defense at the entrance to the harbor. She was, however, repeatedly holed and sinking and grounded before reaching the canal entrance. The Intrepid and Iphigenia did succeed in reaching the entrance to the canal where they blew their charges and scuttled themselves. At this point, the raid seemed to have achieved at least partial success.