When daylight began to pierce the darkness on the morning of June 6, D-Day, German observers on France’s Normandy coast saw spread out before them as far as the eye could see an armada of over 5,300 naval vessels, from the largest battleship to the smallest patrol boat. This invasion flotilla, the most powerful ever assembled, with warships, amphibious ships, auxiliaries, and landing craft from Great Britain, the United States, France, Canada, Poland, Norway, Greece, and the Netherlands, was poised to start the liberation of Europe.
Over two years before that momentous day, British and American military staffs had begun preparations for the invasion of the continent. The London-based staff of Lt. Gen. Frederick E. Morgan, the Chief of Staff to the Supreme Allied Commander (COSSAC), had begun planning for a landing in western Europe back in early 1943. Morgan’s group developed the so-called “COSSAC” Plan for the invasion of France, from May 1943 on code-named Overlord. The naval aspect of that enormous undertaking would later be called Neptune.
The COSSAC plan called for an amphibious assault along a relatively narrow 30-mile (48km) front, with three infantry divisions seizing the beachhead and two others reinforcing them. Morgan unveiled the plan to
Allied leaders at the first Quebec Conference in August 1943 and soon afterwards the US-British Combined Chiefs of Staff approved it in principle. Although the COSSAC planners would have preferred a stronger effort, they did not have the clout to get for Overlord the additional air, naval, and ground forces they felt essential. That year the Americans were focused on the war in the Pacific and the campaign against the U-boat menace in the Atlantic, while the British, especially Prime Minister Churchill, were seriously considering alternative campaigns in Norway and the Mediterranean.
The appointments of Generals Eisenhower and Montgomery to Overlord at the end of 1943 finished the COSSAC plan. Neither was happy about its limited scope, either in number of divisions deployed or its narrow beachhead. By January 1944 the COSSAC plan was being completely revised to include an attack by five infantry divisions abreast on a 61-mile (98km) beach front. Unlike Morgan, these officers, who had the strong support of Roosevelt and Churchill, were able re-emphasize the prior understanding that Overlord hzd first call on Allied resources worldwide.
An officer who shared the views of Eisenhower and Montgomery on the broad front approach was Adm. Sir Bertram Ramsay, selected by the British Admiralty to serve as Naval Commander Allied Expeditionary Force, Ramsay was an easygoing naval officer who possessed a brilliant intellect and the ability to address a problem clearly. This veteran of World War I, and more recent amphibious operations at Dunkirk and in the Mediterranean, was charged with planning and overseeing the naval aspects of the invasion program.
¦ Planning Neptune
During the first half of 1944, Allied leaders, including Ramsay and Rear Adm. Alan G. Kirk, the ranking American naval officer in Neptune, feverishly worked to acquire additional assault divisions and a host of additional landing ships and craft, escorts, minesweepers, and logistic support vessels. The change to the strategic plan meant that embarkation ports and training grounds had to be set aside in southern England already chock-a-block with troops, motor transport, and supplies. Furthermore, the new invasion plan made it clear that the Allies would not have the wherewithal to support a simultaneous and complementary landing in the south of France, code-named Anvil, or to launch the Normandy assault in May, as originally planned. Eisenhower postponed Anvil to August and rescheduled the cross-channel operation for June 5, 1944.
It was soon clear that the Royal Navy could not by itself meet the new operational requirements for Neptune. The British felt compelled to maintain a strong Home Fleet in Scotland in case Hitler’s pocket battleships, cruisers, and other major combatants based in Germany sortied into the North Sea or moved south into the English Channel to contest the Allied landing. The British also feared a foray by the German batdeship Tirpitz deployed in Norway against Allied convoys steaming through Arctic waters to the Soviet Union. As a result, the British kept in reserve three fleet carriers, three modern battleships (which they also chose not to risk to the mines off the French coast), and 16 other major units. British intelligence, however, over-estimated the operational ability of the German surface fleet, whose warships and bases had been the target of Allied bombers for many months and would have been hard pressed to mount a serious attack against the Allies in any area.
The British took drastic steps to provide the additional sailors, warships, and other vessels needed for Neptune. The Royal Navy laid up 49 old combatants and decommissioned a minelaying squadron so that their crews could man more combat-effective ships and craft. The British even transferred soldiers and airmen to the sea service. Finally, the Admiralty recalled ships from the Mediterranean theater, halted the dispatch of units to the Eastern Fleet in the Indian Ocean, and reduced the number of Adantic convoy escorts.
Despite these measures, Eisenhower’s naval staff was concerned they still lacked enough amphibious vessels and bombardment ships to carry out the expanded Neptune plan. Hence, they called on the US Navy to make up the deficit. This led to one of the few acrimonious exchanges between the British and the Americans during the preparations for Neptune. The British felt the Americans were employing too many amphibious vessels in their Pacific operations to the detriment of the European theater. Adm. Ernest J. King, the flinty C-in-C US Fleet and Chief of Naval Operations, disagreed, contending that he had been generous with the allocation to the European theater of Landing Ships, Tank (LST) Landing Craft, Infantry (LCI) Landing Craft, Tank (LCT) and other amphibious vessels.
The crux of the problem was that there were just not enough amphibious types in service to handle all of the Allies’ global require-merits. The high losses in the Atlantic and the Caribbean to German U-boats during 1942 had mandated increased building in US shipyards of convoy escort ships rather than landing ships and craft. The postponement of a 1943 landing in Europe also diverted amphibious vessels to other theaters.
The whole issue became moot when the British shifted LSTs and LCIs from the Mediterranean and increased the troop and vehicle load capacities of their vessels, as the Americans had done. What is more, Adm. King began to send newly constructed amphibious vessels directly from the shipyards to England. Consequently, the Allied naval force had a sufficient number of amphibious vessels on D-Day.
The short-tempered but brilliant King also objected to the dispatch of major US warships to European waters. He felt that the British had an adequate number of these combatants to handle bombardment and naval gunfire support duties. He was persuaded otherwise when Rear Adm. John L. Hall, slated to head one of the two American amphibious task forces, strongly expressed his concern for the success of the operation. Finally in April 1944, King deployed to England three old battleships {Arkansas, Nevada and Texas) and a squadron of destroyers. Still, as the American naval historian Samuel Elliot Morison has correctly observed, “the Royal Navy supplied the lion’s share of gunfire support ships” and, he might have added, the majority of the other ships and craft involved in Neptune.
The Royal Navy (which included units of the Royal Canadian Navy) would put to sea on June 5 with a total of three battleships, 17 cruisers, 65 destroyers, 360 coastal craft, and 447 frigates, destroyer escorts, corvettes, minesweepers, and similar vessels. The US Navy contribution included three battleships, three cruisers, 34 destroyers. 111 coastal craft, and 49 frigates, destroyer escorts, minesweepers and patrol craft. Another 49 French, Polish, Greek, Dutch, and Norwegian-manned warships and combat craft would sail in the invasion fleet. The amphibious landing ships and craft totalled 4,126 vessels (3,261 British and 865 US).
All of the Allied leaders associated with Neptune were conscious of the British amphibious disasters at Gallipoli in World War I and at Dieppe in 1942, while the American knew that even though their recent landing at Tarawa Atoll in the Pacific by US Marines in November 1943 had succeeded, the cost in lives had been much too great. These military professionals knew that an amphibious landing operation, involving coordinated air, sea, and ground operations, was one of the most complex of military evolutions to achieve successfiilly.
To avoid a catastrophe in France, AUied soldiers, sailors, and airmen underwent thorough and continuous training. Rear Adm. John Wilkes, great grandson of Commodore Charles Wilkes, the 19th-century American explorer of the Pacific, was charged with preparing US forces for their part in Neptune. Beginning in December 1943, the energetic admiral put the Americans through demanding training exercises at Slapton Sands and Torquay in Devon. Full-scale rehearsals took place in which the troop units and ships that were slated to fight together also trained together. Much of this training occurred in late April and early May. The Germans helped make this training real. On April 28, nine fast German E-boats burst in on a night exercise in Lyme Bay off the Devon coast and sank two of the precious LSTs before escaping in the confusion. That night off southern England, 600 American soldiers and sailors died, most of them by drowning. Despite this tragedy, the rigorous training regime prepared US and British amphibious forces well.
Furthermore, Allied maintenance and repair units were especially successful in keeping the ships and craft: of the amphibious flotilla operational. On June 1, 99.3 percent of the US and 97.7 percent of the British amphibious vessels were seaworthy and prepared for action.
The Allied navies also emphasized training for the gunfire support mission. Separate teams of naval officers were assigned to the landing forces to help ensure naval gunfire accuracy. The British called these teams Forward Observers Bombardment and the Americans referred to them as Shore Fire Control Parties. These groups, which would go ashore with airborne and amphibious assault troops, trained intensively with the gun directors of their primary support ship. They were trained to call in fire from other Allied ships as well. British and US Navy aircrew of Royal Air Force Spitfires and Mustangs and Royal Navy Seafires trained with the fire directors of the bombardment ships to adjust fire from the air.
The success of the Normandy invasion hinged not only on sound and thorough training but on the preparations for the logistic support of the mammoth enterprise. Allied forces had to seize a beachhead and hold it against determined German counterattacks. But they also needed strength to break out into the interior of France. Thus, the flow of troops, tanks, guns, vehicles, food and fuel into the beachhead had to be heavy and uninterrupted. The Allied capture of Cherbourg, the only major port of the Cotentin Peninsula, would alleviate some of their logistic problems. But this could not be expected to happen early in the campaign ashore, and if the Germans feared losing Cherbourg, they would undoubtedly sabotage the port to render it unusable.
Consequently, the British developed two artificial harbors, codenamed Mulberry, that would be emplaced off the invasion beaches. The design and construction of these pier and pontoon structures, which Morison characterized as a “tribute to British brains and energy,” was handled by the British Admiralty and War Office. Through prodigious effort, British defense plants, shipyards, engineering firms, government agencies, and other sectors of the British warmaking establishment completed both Mulberries in time for D-Day. The Royal Navy was assigned the task of assembling the Mulberry components in four areas off Portland, Poole, Selsey and Dungeness; towing them across the Channel with over 150 US and British tugboats, and forming them into beachhead breakwaters and harbors. Within several days of the landing, the Allies hoped to have both Mulberries functioning, one off the British beaches and one off the American. Each Mulberry was designed to berth seven deep-draught ships, 20 coastal craft, 400 tugs and auxiliary vessels, and
1,000 smaller craft, and handle 7,000 tons of supplies daily.
Allied naval planners, who understood the devastating power of spring storms in the Channel, also felt it prudent to develop five beachhead shelters, known as Gooseberries, for landing craft and other smaller vessels. The Gooseberries would be formed by the sinking of blockships, called Corncobs, just offshore. Once Adm. Ramsay approved the concept, the Allies gathered 69 surplus British and US ships in Scotland.
Other preparations involved operations in proximity to the enemy. Throughout early 1944, the Allies launched small boat forces on missions all along the French coast, not only to deceive the Germans about the true invasion site, but to gather essential intelligence for the landing. For instance, in January the Royal Navy deployed several trawlers and motor launches and midget submarine X-20, all under the command of Lt. Cdr. H. N.C. Willmott, off the proposed American beaches on the Normandy coast. Two British soldiers swam ashore from the submarine and after collecting vital information on the beach sand, shingle, and gradients returned safely to the boat.
Perhaps the most important information available to the Allies, however, was gleaned by codebreakers from intercepted enemy radio
Traffic. American intelligence units hit a bonanza when they picked up a series of transmissions from Berlin to Tokyo made by Gen. Oshima Hiroshi, Japanese Ambassador to Germany. Having just completed a personal inspection of Hitlers Atlantic Wall, Oshima sent his superiors detailed reports of German defenses.
Armed with intelligence such as this, in April 1944, Adm. Ramsay issued his final plan for Neptune. The mission of Allied naval forces was to transport the Allied Expeditionary Force across the sea, help secure and defend a beachhead on the continent, and develop logistic facilities to sustain the advance into France of 26-30 infantry and armored divisions. The admiral stressed that the naval operation was a “combined British and American undertaking by all services of both nations.”
Eisenhower had not only assigned Ramsay overall responsibility for the naval forces connected with Overlord but with control in battle of those naval forces deployed off the invasion coast. The admiral s chief combat commands comprised two task forces. The Western Task Force was led by calm, self confident Adm. Kirk, a veteran of the Sicily landings and commander of the US Atlantic Fleet’s amphibious forces. His contingent included two infantry divisions of Lt. Gen. Omar N. Bradleys US First Army, which would storm the Utah and Omaha beaches on the western flank of the invasion. Kirk’s chief subordinates were Rear Adm. Don P. Moon (Force U) and Rear Adm. John L. “Jimmie” Hall (Force O), who would direct the assaults at Utah and Omaha. The Eastern Task Force, under British Rear Adm. Sir Philip Vian, would land one Canadian and two British divisions of Lt. Gen. Miles C. Dempsey’s British Second Army on 30 miles (50km) of coast between the River Orne and Port-en-Bessin. Responsible for the naval assault forces at the Gold, Juno and Sword beaches were Commodore Cyril E. Douglas-Pennant (Force G); Commodore Geoffrey N. Oliver (Force J); and Rear Adm. Arthur G. Talbot (Force S).
Force B, led by Commodore C. D. Edgar, and Force L, commanded by British Rear Adm. William E. Parry, had the critical responsibility of landing the seven support divisions on the second tide of D-Day, together with the assembly of the Mulberry artificial ports and Gooseberry boat shelters.
For the most part, British and American naval commanders directed the forces of their respective nations, but ships and craft from every national contingent steamed in each of the task forces. Thus British destroyers, French cruisers, and a Dutch gunboat operated in Adm. Kirks command while US coastal craft, two Greek corvettes, and a Polish cruiser fought with Adm. Vians forces.
World History
