At 06:00, before dawn, on 18 November, giant searchlights ("canal defence lights") of the 357th Searchlight Battery, Royal Artillery provided hazy indirect light for the mine-clearing flail tanks supporting the infantry. These tanks moved toward the German mine field between Geilenkirchen and Immendorf, but, on the wet ground, mud lessened the flails' effectiveness and so engineers followed with mine detectors. After a brief artillery bombardment, the 334th Infantry Regiment advanced through the cleared strips at 07:00 and easily secured the high ground east of Geilenkirchen. The right flank gave some concern to U.S. commanders as a counter-attack was expected and fresh German troops appeared to be in the area; the advance to Prummern was delayed until the flank was secured. When the attack resumed, supported by British Sherman tanks, there was steady progress and the regiment's objectives were achieved by late afternoon. The British attack north and west of the town also achieved its objectives by nightfall. The Worcestershire Regiment advanced on Tripsrath, capturing its intermediate objectives of Rischden and intervening woods with little opposition and few casualties. The preparatory bombardment had reduced the Germans' will to resist and rain had exposed much of the minefields. The rain, however, also made it difficult to bring up-armoured support, anti-tank guns and supplies. An unsupported British advance on a copse using universal carriers was engaged by two self-propelled guns and forced back, with heavy casualties. Despite further counter-attacks and "friendly fire" casualties, the Worcestershires occupied Tripsrath after dark, aided by artillery, and held most of the village sometimes with Germans as next-door neighbours.
Artillery bombardment (Source: IWM)
Given the first day's success, XXX Corps' commander Lieutenant General Brian Horrocks directed that the last two phases 3 and 4 should be combined on the 19th. In order to facilitate this, the U.S. 84th continued its advance toward Süggerath, instead of consolidating overnight. A reconnaissance patrol toward Beeck, however, reported an impending German counter-attack on Prummern by two companies of the 9th Panzer Division's 10th Panzergrenadier Regiment, with six tanks. The night attack was fought off, but the American advance toward Beeck was delayed until just before dawn on the 19th. Resistance in Prummern continued until 20 November, when it was finally cleared with the support of British "Crocodile" flame-throwing tanks: the adjacent high ground, "Mahogany Hill", which had held out for two days, was finally captured by an American surprise attack on 22 November. On the 19th, the Worcestershires had been denied supply and support by the lack of a usable supply route, but they fought off a counter-attack by the 104th Panzer Grenadier Regiment of the 15th Panzergrenadier Division. Five Shermans of the 4th/7th Royal Dragoon Guards equipped for traversing mud arrived, but four were almost immediately knocked out by artillery and a Panzerfaust. A second German attack, on Rischden, this time supported by two Tigers and two self-propelled guns, was engaged by PIATs, anti-tank guns and tanks that had arrived and by flanking fire from Tripsrath and it was beaten off with severe losses [for whom?]. Events in the Prummern area had made American commanders cautious, particularly as there was now a gap in the American line between the 84th Division and the 2nd U.S. Armored Division 1.5 mi (2.4 km) distant at Apweiler. This was plugged by the temporary attachment of the 405th Infantry Regiment.
Geilenkirchen itself was subdued relatively easily by the 333rd Infantry Regiment on 19 November, but the Allied advance suffered from the lack of artillery support which had been held back by the fear of friendly fire incidents, as had occurred earlier in the British sector. Two troops of tanks from the British Sherwood Rangers Yeomanry provided close support, although they could not make up entirely for lack of artillery. From Geilenkirchen, the advance continued northeast along the Wurm toward Süggerath. Flame-throwing Crocodiles subdued the increasing German resistance, especially two pillboxes guarding the road into Süggerath. "A few squirts from the flame-throwers, and the Germans poured out ... The bastards are afraid of those flame-throwers and won’t be caught inside a pillbox ...", said one U.S. company commander. The capture of Geilenkirchen opened a supply route to Tripsrath. German artillery heavily bombarded Tripsrath for the next four days, but, sheltering in basements, the British infantry suffered few losses. On the other hand, German defenders of the neighbouring hamlet of Bauchem were subdued by a ferociously effective and uniquely concentrated four hour artillery bombardment on the 20th, and advancing infantry occupied it with no effective resistance. The lead battalion of the 333rd passed through Süggerath, by-passing determined German strongholds. Augmented by a second, fresh battalion, Süggerath was cleared during the night of 19/20 November. The 333rd Infantry was still over a mile short of its final objective of Würm, but there was the possibility of establishing a coherent frontline with XXX Corps on its left and 334th Infantry Regiment on its right. The weather, however, intervened.
Wessex troops moving up to the start line of the attack (Source: IWM)
Intermittent showers were followed by a downpour on 21 November, turning the fields into mudbaths that rendered the tanks ineffective and vulnerable. The direct road to Würm was mined and an alternative side road was blocked by debris and could not be cleared until a bulldozer was used. The U.S. infantry attempted to advance but, without tanks, they were beaten back. When the British Crocodiles were able to advance and assault the defences, there was rapid progress, with defenders surrendering. The mud intervened again, however, bogging down the Crocodiles' armoured trailers. Without their support, infantry attacks on Müllendorf failed, particularly as the German defences had been strengthened by the 15th Panzergrenadier Division. A flanking attack by the U.S. 405th Infantry Regiment toward Beeck on 22 November similarly bogged down against prepared defences. On the other side of the Wurm, British assaults were also beaten off by strengthened resistance.
The mud intervened again (Source: IWM)
Despite the frustrations of 21-22 November, and the failure to capture the final objectives, the purpose of the operation had, in fact, now been achieved. The Geilenkirchen salient had been substantially removed and the U.S. XIII Corps now had room to manoevre. The 84th Infantry Division reverted to U.S. command and further attacks were abandoned on the 23rd. On 23 November, the Worcestershires were relieved by 5th Wiltshires, who had been holding the village of Birgden for the last 12 days. This was welcome for the Worcester men who had suffered continuous shelling in their forward positions in Tripsrath and Rischden.