D-Day 70
h labour So the next Corncob became the ‘key ship’ from which the rest of the Gooseberry sprouted in both directions, and she and those that followed were sunk in the right spots. With experience of local tides and weather, the Planter and his maritime gardeners became expert in sinking Phoenixes using a system of valves operated by sappers; these units were rarely more than a few inches out of line. With practice, the time taken to sink a Phoenix fell to between ten and 20 minutes, depending on the type. Progress on Mulberry A was considerably slower than B, and under pressure from commanders a Phoenix was poorly planted near the entrance in fading light on an adverse tide. Such mishaps could help explain the different fates of A and B in the subsequent storm. More than half the provision for sheltered water was in place at Mulberry B by D+10, though construction of the piers took longer than planned. The first supplies for the Battle of Normandy itself – material other than that needed for the building of the Mulberry – trundled through Arromanches on D+7, and within three days had topped 2,000 tons a day. Activity there did not cease until the port was closed to traffic on December 1, or D+178. However, the Mulberries suffered a hammer blow on D+13 when a fierce storm appeared literally from out of the blue. The Mulberry despatch officer in Britain, a man who constantly scanned the latest weather forecasts, had been assured on the morning of D+12 (June 18) that the outlook was very good. Met men assured the despatcher that the forecast was almost perfect – they were confident that there would be a 48-hour spell of fine, settled weather, with not a hint of an Atlantic low on the horizon. “So arrangements were put actively in hand; all possible tugs were mobilised and set out with a record number of units, including 22 tows of roadway each 480ft long, making a total of nearly two miles,” according to the War Office account. “But not one yard of roadway reached the far shore, because at 0300 hours on the Monday morning (D+13) it commenced to blow and it blew a full gale for three days, such as had not been known in the Channel in a summer for 80 years. “It has been described as second only in portent to the gale which scattered the Spanish Armada in 1588; and it would have scattered and smashed the Allied Armada of small craft, with disastrous results to the forces already ashore in Normandy, had it not been for the Gooseberries provided by the 60 blockships. “They had already rendered
yeoman service during the rough weather in the days immediately following D-Day but during the storm they, as the Eastern Naval Task Force Commander signalled, literally saved the day.” It is thought only some 20 per cent of available smaller craft were lost in the storm – tribute indeed to the Gooseberries and the partially-finished Mulberry B – but the sight on the beaches on D+16, when the storm abated and calm weather returned, was a grim one for the Allies, with hundreds of vessels driven ashore and smashed, or lying two or three deep above the high water mark. Everyone available piled in to help, and within four days of the storm ending daily overall discharge of cargo to the beaches had risen to 40,000 tons and the backlog of waiting ships had been sorted – although the Mulberries played only a minor part in this phase of the operation. Mulberry A “took the gale square on the chin,” according to the 1946 report. It had been all but demolished – only a quarter of its Beetles were moored, compared with 100 per cent at the British port, and more than half of the Phoenixes disintegrated, damaged by untethered Bombardons and being burst by water entering the tops of the hollow compartments, putting pressure on the structure. Nearly all the Corncobs either settled more than three feet, diminishing their effectiveness, shifted position or broke their backs. Inside the breakwater every pier and roadway was damaged, most of them beyond repair. Just one Spud pontoon survived, as the operator (against instructions) winched the concrete platform well clear of the water, ignoring overload warnings. By contrast, Mulberry B, which took “a glancing blow,” was battered and bruised, and its breakwater breached, but it survived – just. It had also afforded some measure of protection to an estimated 500 small craft and other vessels. Having said that, even on the worst day of the storm Mulberry B managed to land 800 vital tons of ammunition. An assessment was carried out, and just over a week later Mulberry A was abandoned, with elements salvaged for use repairing Mulberry B, though the Gooseberry at St Laurent was reinstated using Phoenixes double-banked alongside the Corncobs.
With all effort now on Mulberry B, at least half of the material landed went direct to the beach for almost two weeks while the port was repaired, and a further week was spent expanding the installation. That proved a wise move – when the port returned to full working order around D+28 the tonnage landed almost trebled from the week before, and the increased throughput of 50 per cent above planned capacity continued unabated for two months, with the record for a single day being 11,000 tons. The port also handled increased numbers of vehicles, troops, casualties and prisoners. Liberty ships would go alongside berths along the outer harbour walls and discharge cargo over the side to DUKW amphibious craft and lighters, the latter often transferring goods on to lorries at a Whale pierhead. In good weather, Liberty ships could also be handled just outside the breakwater. Coasters – often between 16 and 22 at a time – would be handled by the Mulberry; some could be beached, some unloaded via the Whale piers and the rest used DUKWs and lighters in the same fashion as the Liberty ships. The defence of the harbour was mainly handled by the craft of the Coastal Forces, which sheltered inside the western arm,
l Lorries are loaded at a pierhead in Mulberry B at Arromanches during June 1944 Picture: © IWM (A 24371)
heading out nightly to ward off German raids, and some 500 anti-aircraft guns, some mounted on the Phoenixes, which were supplemented by the guns of the warships and blockships. Smokescreens from 30 smoke trawlers and a barrage of balloons was also deployed. Because of the need to douse all lights during night-time air raids, and the consequent difficulty recognising and locating ships in the dark, most of the work of the port was done during daylight hours, unless there was a special urgent cargo to process. That also gave the men time to rest and eat. Enemy attacks were troublesome for the first six weeks or so, the bombing proving more nuisance value than destructive, but after that they became sporadic. The millionth man stepped ashore in Normandy on July 4 or
5 – records on the exact date vary. Mulberry B was ‘winterised’ to protect it against autumn storms by pouring sand into hollow Phoenix compartments and providing each caisson with a rough metal roof. With the luxury of hindsight, the Chiefs of Staff decided that the presence of Mulberries had not been the crucial factor in the success of Operation Overlord. In a report by Sir Walter Monckton published in January 1946, the Chiefs of Staff Committee decided that Bombardons had contributed little or nothing to the overall success of Operation Overlord, while the value of the Whale roadways was open to question. While the equipment itself proved effective in all weathers, the various piers within Mulberry were subject to changing uses – the LST and Barge piers were said to be worth their weight in gold, though the LST (heavyduty) pier was late in appearing. The Gooseberry and Phoenix breakwater combination was a success – so much so that the report concluded that “something simpler than Mulberry will probably do [in other similar operations]; a Gooseberry of Corncobs plus an LST pier and perhaps a short barge pier.” It added: “A still further development of the use of amphibious craft is likely to
Bombardons
Eastern Breakwater Eastern Breakwater Western Entrance
Stores Piers
Eastern Entrance LST Pier
contribute substantially to the efficient use of such a harbour.” Clearly, part of the problem of operating the Mulberries was that planners had only factored in a half-gale as the upper tolerance, as the likelihood of anything worse was so remote. In fact, the storm of D+13 proved to be just such a rare event, but within another week or so the Allies had taken Cherbourg and could start to use the port’s sheltered waters while rebuilding damaged infrastructure – although as it was principally a passenger liner port in peacetime, it was never going to have the capacity to sustain the full might of the Allied forces in France. Much more traffic was landed over the beaches than had been expected, which again meant the role of the Mulberry piers was more marginal than expected. But the fact remains that none of the above could be guaranteed. Had Cherbourg not been wrested from the Germans, or the break-out from the beachheads been slower, or the general weather worse than predicted, then the Mulberry option would have been the Allied force’s sole insurance policy.
Dover
l Mulberry B (black outline, yellow beach) compared with the port of Dover (white outline)
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Mulberry LST Pierhead 1: 2: 3: 4: 5: 6:
Beetle pontoon Whale flexible roadway - 80ft x 10ft Spud pontoon - 200ft x 60ft Jack up ‘spuds’ (legs) Artificial beach pontoon for landing craft 2 x LCI(L) mooring berths (158ft x 23ft – 390 tons)
7: 8: 9: 10: 11: 12:
Mooring Spud pontoon Mooring buffers Upper LST unloading deck LST mooring berth. (328ft x 50ft - 3,700 tons) Mooring Spud pontoon General passenger/cargo coaster mooring
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