OVERLORD is set in Motion, May–July 1944
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Chapter 9: Mounting the Operation
The Mounting Problem and Plan
It is unlikely that the average observer in the United States who learned of the Allied invasion of Normandy from his newspaper or radio on 6 June 1944 had much appreciation of the multifarious and almost frenzied activities which occupied the American and British forces in the United Kingdom in the months just preceding the assault. In that period the detailed plans were written, the flow of troops into the United Kingdom reached its height, the big training exercises and rehearsals were held, eleventh-hour efforts were made to fill the supply and equipment shortages, and the coastal areas of the United Kingdom were prepared for the staging of the operation. Finally, in the weeks just before D Day the vast administrative machinery was set in motion by which units were organized for their far-shore missions and moved from their home stations to the embarkation points. The initiation of this hushed and extremely complex process, known as the mounting, marked the first stage in the execution of the great invasion design.
The staging of OVERLORD proved by far the most complex feature of the operation, and called for meticulous planning and an unprecedented degree of coordination and control. On its U.S. side the operation involved the loading of 130,000 men in the assault, initial follow-up, and preloaded build-up echelons alone. After these forces were deposited on the far shore the buildup machinery was to move another 1,200,000 men across the Channel within the first ninety days. For an indefinite period thereafter it was to continue to handle whatever additional formations passed through the United Kingdom on their way from the United States to the Continent.
Allied planners had long been aware of the magnitude and complexity of staging a seaborne invasion, and the theory and techniques of mounting had developed through a long period of trial and error. Exercise HARLEQUIN, held in September 1943, had set the pattern for the eventual development of the mounting procedure, establishing the concept of mounting as a series of steps by which units would be brought to a more and more advanced stage of preparation and formation for the assault and finally embarked for the sea voyage. For most units the process involved three successive steps—assembly or concentration, marshaling, and embarkation. The mounting process normally began with the movement of troops from their home stations to the concentration area. The purpose of this step was to reassemble units which for one reason or another had been split up in the United Kingdom, and to replace equipment and supplies which had been lost, damaged, or consumed in their training or in carrying
out earlier tasks. In practice a unit’s concentration area might actually be its home station if this was located within reasonable distance (fifty to seventy-five miles) of the embarkation area. Troop units arrived intact and self-sufficient in the concentration area and took the first steps in preparing for the sea voyage. They carried out the preliminary waterproofing of their vehicles, acquired additional supplies, and packed their equipment. At this stage assault units also shed their “residues.” Because of the limitations in shipping space it was necessary to move most units in the assault and early build-up at reduced strength, or at “assault scale.” All administrative personnel and over-strength, troops whose services would not be needed during the initial stage of the invasion, were therefore detached from their units in the concentration stage. These detachments, unlike the main bodies of the units, were for the most part administratively self-sufficient; they were concentrated in separate residue camps under the direction of the base section commander and were to be called forward later for embarkation and movement to the far shore, where they would join their units.
After the concentration or assembly, troops moved to the marshaling areas. At this stage units were briefed on their mission in the coming operation, were issued their prescribed supply of rations, lifebelts, maps, and other necessities, carried out final waterproofing, and were organized into the formation which they were to have for the assault—that is, broken down and formed into craft loads. Beginning with this phase of the mounting, troops were to be relieved of all administrative responsibility by static service personnel. This step was necessitated in part by the shedding of residues in the concentration areas, and in part by the fact that equipment would have been packed. SOS troops provided by the base sections were to carry out all housekeeping functions such as messing and quartering for troops passing through the marshaling areas.
The final step of the mounting would be taken when units were called forward to the embarkation points, usually only a few miles distant.1
Preparation for the mounting got under way in earnest in the fall of 1943 after Exercise HARLEQUIN. Responsibility for mounting the U.S. forces in Operation OVERLORD was assigned to the SOS. General Lee in turn delegated this task to the base section commanders, authorizing them to deal directly with the commanding general of the 1st Army Group and with one another on all matters concerning the administrative facilities and installations required. They were charged with a formidable list of responsibilities: locating and constructing concentration and marshaling areas, feeding and housing troops, waterproofing vehicles, issuing emergency supplies, planning the movement of troops, locating and constructing the necessary roads, embarking personnel, equipment, and supplies, preparing ports and approaches, providing hardstandings for thousands of vehicles, supplying recreational facilities for troops during their stay in the marshaling areas, setting up aid stations and hospital facilities for the care of the sick and wounded, and operating depots and dumps for the storage and last-minute
issue of supplies. After the start of the operation the base section commanders were to be responsible also for the receipt, treatment, and evacuation to fixed hospitals or concentration areas of casualties, refugees, and prisoners of war, as well as for the continued mounting of troops. All these missions were to be performed under operational procedures already established by and with the British districts, with which the Americans maintained close liaison.2
U.S. forces were allotted all marshaling and embarkation facilities in southern England west of Poole, inclusive, and shared facilities with the British eastward as far as Southampton. Almost the entire staging area thus fell within the Southern Base Section, which was to handle by far the largest share of the mounting, including the staging of all the seaborne assault forces. Western Base Section was to handle the preloaded build-up forces and paratroop elements of the airborne divisions, and was to share in the mounting of the later build-up. In actual practice the responsibility for the mounting was further delegated by the base sections to their districts, which became the principal administrative agencies for handling the movements.
U.S. forces were allotted all marshaling and embarkation facilities in southern England west of Poole, inclusive, and shared facilities with the British eastward as far as Southampton. Almost the entire staging area thus fell within the Southern Base Section, which was to handle by far the largest share of the mounting, including the staging of all the seaborne assault forces. Western Base Section was to handle the preloaded build-up forces and paratroop elements of the airborne divisions, and was to share in the mounting of the later build-up. In actual practice the responsibility for the mounting was further delegated by the base sections to their districts, which became the principal administrative agencies for handling the movements.
Of the two base sections, Southern had by far the more complex task. It had to provide the bulk of the accommodations for the flood of troops arriving in the United Kingdom from the United States in the spring of 1944, and at the same time it had to prepare for the mounting of all the seaborne assault forces. Eight U.S. divisions were quartered in the Southern Base Section area by January 1944. Within the next five months the number rose to fourteen, and the total U.S. military population of the Southern Base Section doubled, rising from approximately 360,000 to 720,000. This sudden growth in strength made it necessary not only to build new camps but to convert old buildings which had been rejected earlier as unsuitable for military purposes.
Mounting all the seaborne assault forces was a tremendous task for Southern Base Section. The assault elements first had to be mounted for the rehearsals, TIGER and FABIUS I, which took place at the end of April and in the first days of May. Those troops were then to return in mid-May to the marshaling areas where they would remain awaiting final embarkation two or three weeks later.3 When they finally moved out to the ports their places would be taken by the initial build-up forces in accordance with priorities established by the First Army. Once that process had begun it was expected that the marshaling camps would always contain about two days’ flow of troops and that troops would spend only from eighteen to thirty-six hours in them.
Southern Base Section had been divided into four districts, numbered XVI, XVII; XVIII, and XIX. The entire coastal zone from Southampton westward was divided between the latter two, however, and those two districts were responsible for the mounting of all assault elements except the airborne troops. XVIII District (Col. Paschal N. Strong), to the east, was to handle Force O, the OMAHA Beach task force, and XIX District (Col. Theodore Wyman, Jr.) to the west, was to handle Force U, the UTAH Beach force.
The entire coast in the Southern Base
Section zone, extending from Portsmouth westward, was divided into nine marshaling and embarkation areas, four of them falling within the XVIII District and five in the XIX. (Map 10)* [inside back cover] Of the four in the former, one area in and around Portsmouth and Gosport was operated entirely by the British, two around Southampton were to be used by both the British and Americans and were jointly operated, and a split area around Weymouth, the Isle of Portland, and Poole was operated solely by the Americans. All five areas in XIX District were U.S. operated. The nine areas (lettered from A to D in XVIII District and from K to O in XIX District) had a total of ninety-five marshaling camps with a capacity of 187,000 troops and 28,000 vehicles. The number and size of the camps in each area were determined by the out-loading capacity of the adjoining embarkation areas, of which there was a total of nineteen.4 For the organization of Area M, a typical marshaling and embarkation area lying between Plymouth and Fowey, see Map 10.
The other two Southern Base Section districts—XVI and XVII—were to mount glider elements of the 82nd and 101st Airborne Divisions.
Because of the differences in facilities in the eastern and western portions of the Southern Base Section area the two districts mainly responsible for the mounting—the XVIII and XIX—met the problems of accommodation in different ways. The XVIII District to the east contained many large camps, most of which had been constructed by the British and were easily converted. They had capacities ranging from 1,500 to 9,000 men, possessed large messes and recreation halls, and could be expanded fairly readily. Several large buildings used by civilian agencies were also taken over. The XIX District contained fewer large and compact camps, and was harder put to find accommodations for the flood of units which arrived in the spring of 1944. It therefore had to make much more extensive use of the sausage camps described earlier. These small tented camp areas, straddling from five to ten miles of roadway and containing a dozen or more small 230-man camps, had their drawbacks, for they required more personnel for efficient operation, and the wide dispersal of units made control difficult. But they also had their advantages, for camouflage was easy, and they were quickly constructed, and since speed and ease of construction were important they eased the accommodations problem considerably.5
The differences in accommodations in the two districts resulted in differences in mounting techniques as well. American observers at the HARLEQUIN exercise had expressed the belief that the mounting procedure, which used one installation for concentrating and another for marshaling, was unnecessarily complicated. The two processes, they felt, could be accomplished in one area. In XVIII District, where facilities were more adaptable, such a consolidation was begun quite early and adopted as more or less standard practice. The XIX District, because of its limited facilities, planned to concentrate troops in one area and marshal them in another near the port wherever necessary.6
Providing the needed accommodations entailed much more than acquiring buildings or erecting tents. Early in the year there was a severe shortage of beds, and it was necessary for Southern Base Section to buy lumber, wire, nails, and tools on the open market and to build 50,000 double-tiered bunks. Later in the spring an acute shortage of operating personnel developed, which promised to become worse once the mounting machinery was set in motion. SOS officials foresaw this deficiency as early as February and at that time indicated that it would be necessary to use field forces to perform service functions during the mounting of the operation. General Lee estimated that at least 15,000 field force troops would be needed, in addition to some 46,000 SOS troops that were to be taken off other work for this purpose.7
The necessity of calling on combat troops to perform housekeeping duties was fully confirmed with the mounting of the two rehearsals, TIGER and FABIUS, in April. In fact, the original estimates proved too small. At that time the Southern Base Section was given use of the entire 5th Armored Division in the concentration and marshaling areas of the XIX District. In addition, the 29th Infantry Regiment and the 6th Tank Destroyer Group were assigned similar duties in the XVIII District. Even these measures did not meet all requirements, for there was an unfilled demand for specialists in certain categories. There was a persistent shortage of cooks, for example, despite the fact that attendance quotas at the Cooks and Bakers School were increased early in the year in Southern Base. SOS units were ordered to double the normally allotted number of cooks to meet the housekeeping needs of the marshaling areas. As a result of the stepped-up program, 4,500 cooks, in addition to many mess managers, were trained in the first three months of 1944.
The mounting of the assault forces entailed a great amount of construction besides that involved in the provision of the marshaling camps. Additional loading facilities were vital to the embarkation plan, for the ports were unequal to the task of simultaneously loading hundreds of ships, particularly landing craft. This requirement was met largely by the construction of concrete aprons known as “hards” along the water’s edge, some within the ports and others along river banks, where landing craft could nose in and drop their ramps to take on personnel and supplies, and particularly vehicles. Other installations such as engineer depots, advance shops, supply distributing points, railheads, and ordnance recovery points had to be built. Southern Base Section alone increased the number of engineers employed on such projects to 47,500 in May. To service the invasion units, to equip them properly, and to facilitate their movement to the ports, hundreds of still other installations were needed, including dispensaries, sterilization and bath facilities, field bakeries, POL and water distributing points, post offices, ration dumps, traffic regulating points, military police installations, and all types of supply distributing points.8
Mounting in Western Base Section, which held six U.S. divisions at the end of May, proved considerably simpler than in the southern coastal area, primarily because seaborne assault units were not
Waterproofed tank recovery vehicle moving from a “hard” onto a landing craft.
involved. Western Base’s initial responsibility was to mount the preloaded build-up through the Mersey ports and Bristol and to marshal the paratroops of the two airborne divisions at airfields in eastern England. The base section then had to handle a portion of the later build-up via the shuttling of ships between the United Kingdom and the far shore. Because its units did not have to be broken up and formed into assault teams and craft loads, they were for the most part embarked from quays in the normal manner, which required little of the meticulous planning necessary for the assault forces. The less complicated marshaling process permitted a more centralized administration. Western Base Section constructed only twenty-four marshaling and four residue camps to accommodate its seaborne build-up forces and generally located them farther from the embarkation points than in the Southern Base Section. Reduced scales of accommodations were adopted, and existing camps were expanded by the use of tents where necessary. They were operated by two engineer general service regiments—the 360th and 373rd—augmented by camouflage, fire-fighting, depot, and various other detachments, rather than through the district headquarters. There was no resort to the sausage camps, although
such areas were surveyed and held in reserve. Part of Western Base’s build-up forces were to be staged in Northern Ireland, and a small emergency staging area was constructed for this purpose on the outskirts of Belfast.
The mounting of airborne units was a separate and somewhat special problem. Both paratroops and glider troops were marshaled at their departure airfields, where marshaling camps known as “eggs” were constructed, each camp having a capacity of about 200 men.9
The Mounting Begins
The SOS mounting plan was issued on 20 March 1944, and the plans of the base sections and subordinate echelons followed soon after. Under the plan Task Force O was to marshal in the Portland–Poole area, Task Force U in the Torquay–Dartmouth sector, and Force B (follow-up) in the west country around Falmouth and Plymouth. Preloaded build-up units were to be embarked through the Bristol Channel ports, and the earliest build-up divisions via the shuttle service through Southampton.
Months of toil had gone into the army and army group Buildup Priority Lists, which specified the order in which hundreds of units and detachments were to embark for the cross-Channel voyage in the first ninety days. Allied planners nevertheless had foreseen the need for an effective movement control organization which would see to it that marshaling and embarkation were carried out in the order and speed which made the best possible use of shipping without clogging the camps, roads, and embarkation points, and, more important, would permit the modification of priorities in shipments in accordance with tactical requirements insofar as the available shipping would allow. In other words, machinery was needed which would regulate the movement of troops through the mounting process and also permit alterations in the course of the build-up. In addition, a centralized control of ships and craft shuttling between the United Kingdom and the Continent was needed to insure flexibility and economy in the use of shipping.
For this purpose the Buildup Control Organization (short title, BUCO), consisting of British and American ground, naval, and air representatives, was established at Fort Southwick, near Portsmouth, under the joint direction of the Allied Army, Naval, and Air Commanders-in-Chief. Maj. Gen Charles S. Napier, Director of Movements in the War Office and later Chief of Movements and Transportation, G-4, SHAEF, had conceived the basic idea for BUCO and had worked out many of the details personally. Through representatives of the Allied Naval Commander, the British Ministry of War Transport, and the U.S. War Shipping Administration BUCO was to control the movements of ships and craft; through the representatives of the War Office, the Air Ministry, and Headquarters, ETOUSA, it was to control the movement of personnel and vehicles to the embarkation points.
BUCO was not an agency of the Supreme Commander. It was to operate directly under the tactical commands most immediately concerned with the build-up of troops. Under the chairmanship of Brigadier G.C. Blacker (Br.), who represented the Commander-in-Chief, 21 Army Group, BUCO had both U.S. and
British zone staffs. The U.S. Zone Staff consisted of a chairman (Col. Eli Stevens), representatives of the major U.S. commands involved in the build-up, and an advisory representative of the War Shipping Administration. In practice, the U.S. Zone Staff functioned directly under the senior American tactical commander on the far shore (the Commanding General, First Army, until 1 August and the Commanding General, 12th Army Group, thereafter). Supervision by the representatives of the joint commanders in chief was limited mainly to decisions affecting the allocation of shipping between U.S. and British forces.
Two subordinate organizations were established to act as executive agencies in carrying out BUCO’s decisions. These were Movement Control (MOVCO) and Turn-Round Control (TURCO). On its U.S. side MOVCO was in effect an agency of the ETOUSA chief of transportation and had the mission of supervising the movement of troop units from their home stations to the embarkation points. It planned to accomplish this roughly as follows: On the basis of the over-all troop Buildup Priority Lists, prepared and amended from time to time by First Army and 1st Army Group, BUCO prepared appropriate lists for each embarkation area indicating the order in which units were to embark for the next three weeks, and in addition periodically released a forecast of loadings. On the basis of this information MOVCO in turn was enabled to prepare a periodic “force loading forecast,” projected ten days in advance, and finally a daily “force movement table.” It issued force loading forecasts for each embarkation area, indicating the allocation of craft and shipping to units, the approximate time of arrival of units in marshaling areas, and their loading times, thus giving the base sections and embarkation areas an indication of movements that could be expected. The final movement schedule took the form of a daily movement table issued by U.S. MOVCO to Headquarters, Southern Base Section, the marshaling areas, and the embarkation areas covering a twenty-four-hour period of flow. In effect, the daily table was an extract from the loading forecast brought up to date with the latest amendments in priorities, and was the basis for a detailed allocation by the embarkation area headquarters of personnel and vehicles to individual craft and ships. It also served as instructions to the transportation agencies in the base sections, enabling them to issue road and rail movement tables for the movement of units forward into the marshaling areas.
TURCO was organized to assist naval commanders in controlling the movement of ships and craft so as to achieve the optimum rate of turn-round of vessels between the far shore and loading points. On instructions from BUCO it was responsible for bringing the prescribed number of ships and craft into designated embarkation points.10
In coordinating the actual marshaling and embarkation with these two agencies the two base sections again developed different methods. Western Base Section set up a simpler and more centralized system of control. All movement orders were the responsibility of the Transportation Corps, which controlled the location and movement of all units through a headquarters established at Newport and a subsection
headquarters at Swansea in the Bristol Channel area. The district headquarters had no intermediary role in this system. Southern Base Section set up a more elaborate supervisory agency known as Embarkation Control, or EMBARCO, which was intended to serve as a nerve center for the entire Southern Base Section mounting complex. EMBARCO planned to maintain a record of the location and capacity of all concentration and marshaling area camps, and to keep informed at all times as to the location of every unit in the mounting process. For this purpose enormous boards were set up in a large Nissen hut at Southern Base Section headquarters near Salisbury, where the strength and location of all units were charted. Through this agency Southern Base Section hoped to exercise detailed control over every movement from concentration area to embarkation point, issuing the necessary movement instructions to the districts. The system proved difficult to operate, as will be shown in the next chapter.11
The machinery in Southern Base Section was set in motion late in April with the mounting of forces participating in the final rehearsals. Force U, consisting principally of the 4th Division and the 1st Engineer Special Brigade and totaling 30,452 men and 3,569 vehicles, was marshaled by the XIX District. In mounting Exercise TIGER, however, a procedure was followed which was contrary to established practice. Units were broken down into craft loads at their home stations before their briefing, a step that caused considerable confusion in the marshaling camps. SHAEF intervened and ordered troops to be briefed by unit rather than by craft load in the future, thus making mandatory the standard mounting procedure originally planned. There were other defects in these initial stages of the mounting. Traffic did not move smoothly in the embarkation stage, and there was poor liaison between Army and Navy officials.
In XVIII District the marshaling of Force O, which consisted mainly of elements of the 1st and 29th Divisions and the 5th and 6th Engineer Special Brigades and totaled 29,714 men and 3,241 vehicles, also encountered difficulty, owing principally to the complicated movement schedule. Some units were misdirected; a few could not be located immediately; and the dissemination of information and instructions was faulty, in some cases as a result of an overemphasis on security.
Portions of the build-up forces, including the 9th Infantry and 2nd Armored Divisions, rehearsed their marshaling and movement to the point of embarkation, and then returned to their concentration areas. Upon the completion of these rehearsals and the return of assault units to their marshaling areas the movement of Force B, the follow-up force of 26,492 men and 4,431 vehicles, also got under way.
In the weeks just before D Day a tremendous increase in movements took place in England, particularly in the coastal areas. The transportation network became alive with trucks, combat vehicles, and train after train of foot troops, and cities like Gloucester, Cheltenham, Cirencester, and Oxford became critical traffic bottlenecks. In many areas, particularly where the sausage camps had been established, embargoes on all traffic were imposed, creating hardships on the local inhabitants and in some cases causing resentment. On all other highways movements
were rigidly controlled, with military police guiding all convoys in their movement through the mounting process. The Transportation Corps assigned 478 officers and 2,583 men from group regulating stations and traffic regulating groups to Southern Base Section alone for the control of troop movements.12 Upon arrival at the regulating points convoys were checked for their make-up by base section personnel, and then were escorted to the designated camps. Assignment of a camp area depended on the type of vehicles in the unit, the roads it was to travel, and the time schedule. At the edge of the camp the units were met by a representative of the camp commander, who indicated parking areas. Vehicles were then parked, camouflaged, and “topped off” with gasoline, and guards were posted. The troops then marched into the camp, which was usually less than a mile distant. There the unit was once more checked against the movement forecast, and troops taken to the quarters areas and assigned blocks of tents. After being briefed, units were broken down into craft loads. Thereafter they awaited the final embarkation signal.13
In the vital marshaling phase of the mounting the assault forces were placed in final readiness, in both supply and organization, for the cross-Channel movement and actual assault of the enemy beach. It was in the marshaling area that the soldier was issued the items which probably first impressed him with the real nature of coming operations. For there, during the waiting period, he received such items as antiseasickness pills, water-purification tablets, emergency rations, heating units, vomit bags, dusting powder, and a lifebelt, and there he donned the impregnated clothing and applied to his shoes the paste intended to protect him against chemical warfare. Perhaps the most convincing sign that this was not to be just another dry run was the payment of 200 francs in the new French currency issued by the Allied military government.
Once these details were out of the way the soldier might ease the long wait with a game of baseball or poker, he might go to a movie, he might read the Stars and Stripes, Yank, or the special issue of Army Talks called “Achtung,” specifically written for the men scheduled to enter combat on the Continent. Extraordinary efforts were also made to indulge the men’s taste and appetite in these last few days in the United Kingdom. Fresh meat and white bread were regular items on the menu in this period, and special precautions were taken to guard the diet against foods conducive to seasickness in the case of seaborne assault forces, and against gas-forming foods which might induce stomach cramps in the case of paratroops. In an unaccustomed display of kindness, the Army even allowed some troops to sleep through breakfast and then served them an extra-large noon meal.14 Mobile bakeries provided fresh bread; laundry and shoe repair units provided other essential services. Ordnance patrols circulated through the areas, checking waterproofing, making minor repairs, and occasionally replacing vehicles or other equipment.
Maintaining adequate security was another vital aspect of the mounting, entailing
protection against air attack as well as against the leakage of information. Once the briefing began at the end of May a complete security seal was imposed on all marshaling camps, wire was strung around the perimeter of each camp, all contact with the outside was controlled through gates, and more than 2,000 counterintelligence corps personnel ceaselessly covered their beats to prevent strays from entering or leaving the camps without authorization.
Because it was impossible to conceal completely from enemy eyes the tremendous concentration taking place in southern England, both on land and along the shores, the Allies expected the Germans to send bombers over the marshaling and embarkation areas. To provide air protection against such attacks an antiaircraft brigade was attached to Southern Base Section, the heavy antiaircraft artillery being manned by the British, and the light guns by Americans.15 Camouflage was another logical protective measure. Instructions on camouflage measures in the marshaling areas were issued in March, and camouflage discipline began even with the selection of mounting installations. New construction was carried out with the minimum of disturbance to the ground pattern; and there were periodic inspections by both visual and photographic aerial reconnaissance. Both districts of Southern Base Section were given engineer camouflage units (from the 604th Engineer Camouflage Battalion). Officers from these units gave standard camouflage instruction to the task forces as they passed through the camps, erected model camps for demonstration purposes, and enforced camouflage discipline. The 604th Camouflage Battalion painted 18,000 tents in the sausage camps with reclaimed camouflage paint, and also repainted much sand-colored equipment originally designed for Operation TORCH. The goal of the battalion was to render marshaling areas unrecognizable at 10,000 feet.16 In Western Base Section preparations were made for the smoke-screening of some of the big general depots, like G-40 at Barry in southern Wales.17
Two onerous problems—making up supply deficiencies, and waterproofing vehicles—added greatly to the administrative burden of the mounting. In theory, every American unit in the United Kingdom should have been properly equipped either before departure from the United States or from pre-shipped stocks shortly after arrival in the theater. In actual practice many units lacked portions of their basic equipment for varying periods of time after they arrived in the United Kingdom. Such shortages should have been made up at their home stations by normal requisitioning. But again practice often fell short of theory. Either because the equipment simply was not available, or because late arrivals in Britain had too little time, emergency issue of many items was necessary in the last weeks before the invasion. This continued after the mounting had already begun, and therefore at a time when the SOS administrative machinery was already heavily taxed.
Deficiencies within the assault units were attended to first, for they had been noted in the course of the exercises. By the time those units returned to the marshaling areas after the final rehearsals most of their shortages had been eliminated. The
build-up divisions, however, started the marshaling process with serious shortages. The Ordnance Service was particularly hard pressed to meet late demands, for it already had many responsibilities in the mounting. Troops were scheduled to arrive in marshaling areas with ordnance equipment checked and with complete combat loads of ammunition. Base section mounting installations were to provide only the day-to-day maintenance and replacements normally required while units were in the camps, and certain services connected with the mounting. The Ordnance Service accordingly set up field depots and field service points to issue limited quantities of new equipment and ammunition and to repair or replace vehicles. It also provided teams to test waterproofing and wreckers to clear highways in case of accidents.
But many units began the marshaling process with little or no ordnance equipment, and for a time the supply of these units was badly snarled. Meeting eleventh-hour deficiencies of equipment therefore proved an unexpectedly heavy burden. Non-divisional units made the heaviest demands, and the condition of their vehicles and other equipment was inexcusable in many cases. One unit with a T/E calling for 136 carbines arrived in the marshaling area without a single weapon and without ammunition, creating a problem which the Ordnance Service was neither prepared nor expected to cope with during the mounting process. Many showdown requisitions had been submitted but had not been filled. In some cases they were canceled without notice to the requisitioning unit. Providing the initial issue of T/E equipment was made difficult in many cases by the fact that First Army had been permitted to draw replacements in advance of the operation, thus exhausting surplus stocks. Some of the needed equipment was known to exist in First Army dumps, but it could not be obtained for lack of the necessary authority on the part of the base sections. Sufficient priority was eventually given the base section requisitions, and the situation began to clear up rapidly at the end of May. In the end almost all needed equipment and supplies were obtained.
Similar situations developed in connection with medical and signal supply. There were critical shortages of some signal equipment until the very date of the invasion, and in the case of medical supplies the Western Base medical officer and depot personnel intervened in the last weeks to get vitally needed items released and issued to the using units.
Many an emergency was attributed to the failure to follow existing instructions. Procedures for handling supplies and equipment in an amphibious operation had long since been laid down in a guide known as “Preparations for Overseas Movement, Short Sea Voyage” (POMSSV). Had more of the field force units followed this bible, many crises and anxious weeks could have been avoided.18 In some instances transient units left camps in a deplorable condition. Some camps were below standard, creating sanitation hazards. Fortunately, medical troops were able to expand their facilities and prevent serious threats of epidemic.19
Waterproofing of vehicles was an inescapable requirement. That stage in the landings when vehicles left the ramps of landing craft and entered the water was expected to be a crucial point in the
assault. Unless adequate precautions were taken, not only might many vehicles be drowned in the sea but vehicles stalled at the end of a craft’s ramp could effectively prevent the unloading of other vehicles at that spot. This threat was a great deal more critical in the OVERLORD landings than in the Mediterranean operations because of the greater tide ranges in the Channel. A rising tide could block salvage efforts for many hours.
With these problems in mind great efforts were made both in the United States and the United Kingdom to develop satisfactory waterproofing techniques. Essentially, the problem was one of developing a compound which would effectively seal the vital parts of vehicles and yet be easily stripped off after the vehicles were landed. British experiments begun early in 1942 led to the developments of a compound which was used by both the British and Americans in the North African landings. Experimentation continued after TORCH, and in the spring of 1943 an experimental station was opened at an American ordnance depot in the Southern Base Section where shop facilities and beaches for wading exercises were available. In January 1944 the station was given full responsibility for developing an adequate waterproofing technique. This included the development of proper methods of handling all ordnance equipment in amphibious operations, developing a satisfactory waterproofing material, and the coordination and supervision of all training and experimentation in waterproofing. In the meantime trials with jeeps and trucks were held off a beach near Plymouth, and a training film was prepared by the Army Pictorial Service. Progress was satisfactory enough by the summer and fall of 1943 to start classes for the training of instructors and inspectors in December. Under specifications laid down by the ETOUSA G-3, the Amphibious Division of the Ordnance Service trained more than 3,500 men as waterproofing instructors and inspectors by July 1944.
The basic material adopted was a British product known to the Americans as asbestos waterproofing compound, which consisted of grease, lime, and asbestos fibers. Metal tubing was used to extend air vents in gas tanks and crank cases, and flexible tubing for carburetor air intake extensions and exhausts. Metal stacks and adapters and ventilating ducts were built for armored vehicles to enable air to be drawn in and exhaust to be blown out, a release mechanism permitting the stack to be jettisoned by the driver after the tank reached shore.
The actual waterproofing was to be accomplished in three steps. The biggest portion of the job was done in the home camps. Vital parts of the motor and wiring were left exposed at this stage, since they could not withstand sealing for any extended driving. Additional work was accomplished in the marshaling areas, and the final sealing was done after vehicles had been loaded. In a reversal of the process, a minimum of de-waterproofing was to be accomplished immediately after the vehicles left the water on the far shore, and the larger job of stripping the compound was handled later. Standardized procedures were developed and publicized for all vehicles and for other special equipment such as Signal Corps radios.
Until March 1944 field force units sent representatives to the experimental station in Southern Base Section to be trained in waterproofing methods. It was decided at this time, however, that waterproofing inspection
should be performed by specially trained personnel provided by the Ordnance Service. In addition to carrying out the responsibilities already listed, Ordnance now had to furnish inspectors, it had to send welding teams to mount stacks and shrouds on tanks, it had to prepare and circulate instructions on salvaging waterproofed equipment on the far shore, and it had to do the actual waterproofing of all replacement ordnance vehicles. An ordnance base automotive maintenance battalion and a base armament maintenance battalion provided personnel to act as waterproofing inspectors in Southern Base Section. In Western Base Section First Army provided over a hundred men for inspection teams, and qualified ordnance waterproofing detachments from the SOS were also stationed at each camp. Actual waterproofing was carried out by field forces units, many drivers having attended the Ordnance training schools in the two base sections. Materials were issued for 137,041 wheeled and semi-tracked vehicles, 4,217 full-tracked vehicles, and 3,500 artillery pieces. Waterproofing of vehicles of the build-up forces continued for a month after the invasion, after which it became feasible to land vehicles dry shod.20
Both base sections suffered acute shortages of manpower in operating the mounting machinery. The demands for service personnel actually compounded a preexisting shortage, and some units found themselves with overlapping missions—attached to a base section in the United Kingdom to assist with the staging, and assigned to the Advance Section and scheduled for early movement to Normandy. Diverting combat units to service duty undoubtedly eased the situation but was not an unqualified success. Combat troops were untrained in many of the assignments they were called on to perform, and latecomers even among the SOS units were seriously handicapped by inexperience and lack of adequate orientation in the plan and all its intricacies. Men were called on to work long shifts to meet the demands of the mounting schedule. Southern Base Section alone employed 43,000 men in the process, 20,000 in XVIII District and 23,000 in XIX District, excluding troops used in mounting the airborne forces.21 To make matters worse, many units, choosing to ignore instructions, needlessly added to the burden of the mounting machinery by arriving in the marshaling areas with over-strengths and residues in addition to their assault echelons. Others arrived with equipment in excess of that which could be accommodated on unit vehicles or on landing craft and ships, on which space had been carefully allocated. The excess baggage had to be shipped to the proper port for loading on cargo vessels, and its delivery to the far shore consequently was delayed. Such practices were in clear violation of mounting instructions and caused unnecessary confusion in the marshaling areas.22
The briefing of officers in Forces O and U finally began on 22 and 23 May respectively. In the case of the 1st Engineer Special Brigade, headquarters staff officers visited all field units and briefed unit officers who, in turn, briefed the men under their command. Some headquarters formed briefing teams, which moved from unit to unit and outlined the plans. In many cases they used excellent visual aids,
such as sponge rubber models of the beach areas as well as large-scale maps and aerial photographs. Security precautions were doubled, and marshaling areas were patrolled night and day. In this critically important period a few well-executed enemy air raids might easily have disrupted plans. But only a few minor raids took place, the most serious of which occurred on the night of 30 May, when German planes dropped several bombs in the bivouac area of an ordnance battalion near Falmouth in Cornwall. Twelve men were killed and nineteen wounded; but replacements were obtained immediately and the unit was at its former strength when it embarked.
Just the problem of maintaining communications with the many units was a tremendous one. Because marshaling camps were scattered throughout southern England, it was often difficult to locate units to inform them of changes in plan, plans which were highly classified and had to be delivered by courier and then disseminated to subordinate echelons. One major change in the tactical plan was made only a few days before embarkation. This was the change resulting from the discovery of additional German strength in the Cotentin, which prompted the VII Corps to shift the drop zones and area of operation of the 82nd Airborne Division so as to assure the winning of the beachhead. The change had no effect on the mounting of units scheduled for the D-Day assault, but certain follow-up and build-up units were now given new priorities and phased forward.
In the meantime the “mounting” of supplies had also begun. The loading of vehicle ships, coasters, LCTs and barges got under way in the second week of May, most cargo being prestowed to meet the desires of the First Army. All supplies scheduled for delivery on the far shore in approximately the first fifteen days were loaded before the operation was actually launched. Several ports specialized in loading certain commodities. Llanelli, Sharpness, and Port Talbot, for example, were used exclusively for POL; Penarth and Fowey were primarily ammunition ports; heavy engineer and other out-of-gauge equipment was handled at Cardiff; and a fleet of 112 vehicle-loaded Liberties operated mainly out of Southampton.23 In this way equipment that had crossed the submarine-infested Atlantic in 1943, and cargo that more recently was piled on the wharves of the New York and Boston ports—oil from wells in Texas, jeeps from Detroit, M1’s from Massachusetts, radios from Pennsylvania, artillery shells from Illinois, K-ration cheese from Wisconsin, blood plasma from a town in Tennessee—found their way into the holds of vessels which soon would converge on the Normandy shore.
Late in May the build-up of certain combat units was moved forward, and a last-minute accommodation had to be made to meet the new supply requirements. Since shipping was closely allocated and loading was already well under way, special measures had to be taken to find space for additional supplies. Part of the requirement was met by the acquisition of extra barges which could be beached on D plus 1. More space was acquired by the expedient of loading the vehicles of certain truck companies which had been left empty for just such an emergency. Nearly 4,000 tons of supplies were carried in this manner.24
As the marshaling of men, vehicles, and
Loaded landing craft and ships for the cross-Channel voyage
supplies of the assault forces began, the warships and landing craft which were to carry and escort these forces were also being assembled by the Navy. The assembly of craft for the assault forces began after the Allied Naval Commander, Admiral Ramsay, issued his operation order at the end of April. The American naval forces were organized as the Western Naval Task Force, commanded by Rear Adm. Alan G. Kirk, and comprised the two assault forces and one follow-up force. Assault Force O (Rear Adm. John L. Hall, Jr.), totaling nearly 1,200 ships and craft, provided the lift and necessary naval gunfire support for the OMAHA force, and Assault Force U (Rear Adm. Don P. Moon), totaling nearly 800 vessels, provided the lift and support for the UTAH force. Elements of both forces participated in the TIGER and FABIUS I rehearsals and then returned to port for final repairs and refitting. Force B (Commodore Campbell D. Edgar), with about 500 ships and craft, constituted the follow-up force for OMAHA Beach.
For the cross-Channel movement Task Force O was organized into five convoys. Most of its craft were assembled at Portland and Weymouth, and the remainder at Poole. Assembly was completed by 30 May, and loading began the following day. Task Force U was organized into twelve convoys. Its loading ports were more widely scattered, extending all the way from Falmouth, in Cornwall, to
Poole, and the assembly of the force was therefore more difficult. Force U was given somewhat greater fire power, since it was to operate on the right flank of the invasion force and counter enemy naval attacks from Cherbourg and the Channel Islands. Its craft were assembled and ready to load on 30 May.
Embarkation of both assault forces and the follow-up force was completed on 3 June, and the marshaling of the remainder of the OVERLORD forces was in full swing. With the loading of the assault forces completed and the task force convoys assembled along the southern coast of England, the cross-Channel movement now awaited only the signal from the Supreme Commander.