Chapter 8: Training and Rehearsing for Operation OVERLORD
Earlier Amphibious Experience
One of the outstanding features that distinguished U.S. operations in World War II from those of 1917–18 was the extent to which the technique of the amphibious assault was developed and employed. The high degree of perfection achieved in both the tactical and logistical aspects of amphibious operations in World War II was the more remarkable in that it represented progress made chiefly after the war began. At the start of the conflict there was little in the way of training centers, proven techniques, or special equipment designed for the amphibious type of operation, particularly for its logistic aspects.
This lack was serious indeed, for an amphibious assault is as much a supply operation as a tactical one. Perhaps at no point in modern warfare do tactics and logistics rub elbows so intimately as in the initial stages of a landing operation. Assault formations of necessity travel light, carrying only the most essential maintenance items such as rations and ammunition. Sustaining and reinforcing them require the immediate—in fact, the almost simultaneous—organization of the assaulted beaches for supply, For a brief moment tactical and supply operations may almost merge. Once the beaches have been cleared and secured they cease to be a battlefield and become a logistic base whose main function is to insure a steady flow of supplies and reinforcements.
The U.S. Marine Corps had prepared a “Tentative Manual for Landing Operations” in 1934, much of which later found its way into the Army field manual titled “Landings on a Hostile Shore” (FM 31–5). In conjunction with the Navy the Marines had conducted a series of fleet landing exercises in the thirties to test their amphibious doctrine, and U.S. Army units participated in those of 1937 and 1938, and again in 1941 and 1942. Throughout the exercises the main emphasis was on the tactical aspects of amphibious assaults, and the doctrine of beach organization and techniques of supply handling got only secondary consideration.1 Shore party organization was particularly faulty, and there was no clear division of authority between ground and naval units. While the exercises undoubtedly profited the Army units taking part, they left much to be desired so far as the logistic aspects of amphibious warfare were concerned, and the entrance of the
United States into the war in December 1941 found amphibious supply techniques in a relatively early stage of their evolution.
Japanese successes in the Pacific gave added impetus to the development of amphibious techniques and equipment in the United States. In the winter of 1941–42 the Japanese launched a series of amphibious operations which carried them into the Philippines, New Guinea, the Aleutians, the Malay Peninsula, and the Netherlands Indies. These landings were either on a small scale or unopposed, however, with ports being captured intact, and they gave little indication of the complex problems connected with large-scale assaults on well-defended shores. Nevertheless they underscored the necessity for devoting greater effort to the development of amphibious warfare and to the production of special equipment. The U.S. Navy took steps to increase the production of landing craft, while the Army devoted additional effort to the development of equipment such as the amphibian truck. The British gave particular attention to commando training and to operations employing landing craft.2 The first Allied amphibious operations were undertaken in August 1942, when U.S. Marines landed on Guadalcanal and a predominantly British-Canadian force raided the German Atlantic Wall at Dieppe. Both landings provided experience in landing techniques but were on a scale barely suggesting the scope of a full-scale invasion operation.
Early in 1942, meanwhile, the Army had embarked on its own amphibious training program, although it again had units take part in Marine-sponsored exercises in January and during the summer. In March the War Department directed the Army Ground Forces to select a site for an amphibious training center, and the Corps of Engineers was instructed to train enough boat crews and maintenance units to allow divisional and joint training under the Army Ground Forces to begin that summer. Three months later Col. Daniel Noce (promoted to brigadier general in July) organized the Engineer Amphibian Command at Camp Edwards, Mass. The Army Ground Forces meanwhile established the Amphibious Training Command (later renamed Amphibious Training Center), also concentrating its activities initially at Camp Edwards.
The Engineer Amphibian Command was activated principally to train boat crews which the Army Ground Forces expected to use in instructing divisions in amphibious landings. But this concept of engineer responsibilities was immediately broadened, and steps were taken to combine all the units needed to provide transportation, organize the beaches, evacuate wounded and prisoners of war, and handle the build-up of supplies for a division in a shore-to-shore operation. In this way a boat regiment, a shore regiment, and various service units were combined to create the 1st Engineer Amphibian Brigade, which was activated on 15 June. The shore regiment, its key unit, was to be trained to assume responsibility for all supply and engineering functions in the beach area, and the engineer boat regiment was to operate small landing craft and carry out other shore-to-shore operations. An amphibian signal company was added to handle communications, a medical battalion
to evacuate the wounded, a quartermaster battalion to operate supply dumps, and an ordnance platoon, a boat maintenance company, and a depot platoon from a base shop battalion to repair vehicles and craft.
Formation of the 1st Brigade by no means crystallized amphibious supply doctrine. The composition of the brigade was still tentative, and its functions were not yet clearly defined, partly because the respective spheres of responsibility of the Army and Navy in a landing operation had not yet been clearly defined. While the brigade was designed to provide both logistical and combat support, the tactical role received the main emphasis at first. Since it had barely a month to ready itself for joint training with the Army Ground Forces, the brigade could not form its many units into an integrated team and had little training in the actual movement of supplies. The 1st Brigade actually received little training in the United States beyond boat operation, beach development, and hasty road construction. In July it was made available to the Amphibious Training Command of the Army Ground Forces for joint exercises, but its training was again cut short, for it was almost immediately alerted for movement to the United Kingdom, and special efforts had to be made to fill its equipment shortages.3
In the United Kingdom up to this time developments in amphibious warfare were confined largely to its tactical aspects and were carried on by the Commandos under Admiral Mountbatten, who took command of Combined Operations Headquarters late in 1941. American interest in commando training was evident from the start, and in the spring of 1942 arrangements were made to create an American section at Combined Operations Headquarters and to train American Rangers with the British Commandos.
The development of supply methods and far-shore organization proceeded more haltingly. The 531st Engineer Shore Regiment, one of the key units of the 1st Brigade, received some basic instruction at the British Amphibious Training Center at Inveraray in Scotland, but most of the units of the brigade were scattered upon arrival in England, and for some time its role in a cross-Channel operation was indeterminate. In the United Kingdom all U.S. amphibious training was turned over to the Navy, as was the responsibility of providing boat crews for shore-to-shore movements. Consequently the boat regiment, one of the brigade’s basic units when first organized, was disbanded. The brigade’s responsibilities henceforth were limited strictly to ship-to-shore and shore operations, and its combat engineers, who had become boatmen, now became stevedores.4 In fact, there was opposition from the Navy to the retention of any organization higher than a battalion, and the 1st Brigade itself narrowly escaped extinction.5 Before the North African operation in 1942, therefore, no standard amphibious doctrine had been developed, and few amphibious techniques had been tested. Landing rehearsals conducted in Scotland just before the convoys sailed afforded no training in the vital problem of unloading vehicles and supplies.
Operations in the Mediterranean inaugurated a more extensive schooling in the logistic aspects of amphibious warfare, with TORCH providing the first lessons. When that operation was finally launched, the lack of training and experience was much in evidence. Critiques of it pointed to many errors and underlined the need for great improvements in training, planning, and equipment. Many of the criticisms applied particularly to the faulty supply operations, the major weaknesses being poor coordination between the various forces, undeveloped amphibious techniques, divided authority, insufficient training, poor staging, and bad combat loading. The need for better landing craft and the need for training in the actual handling of supplies across beaches were emphasized, for the time it took to land supplies exceeded all estimates.
The North African operation can hardly be regarded as a prototype of the later OVERLORD operation. It involved a much longer sea voyage, and the amphibious phase of supply operations was actually very short, for the ports were quickly brought into operation and the beaches abandoned. But TORCH did point the way with the practical experience it gave in the handling of landing craft, unloading, the establishment of beach dumps, improvement of exit roads, and so on.6
Efforts were immediately made to rectify the deficiencies of the TORCH operation, particularly in landing craft, combat loading, and amphibious techniques and training. Developments in the United Kingdom, which included the setting up of a planning school, will be covered later. In North Africa itself the first major change came when the Army dropped its control over landing craft. A more important development was the organization of a large amphibious training school where experiments could be carried out and key units could be given training in ship-to-shore operations. During the winter such a training center was constructed by the 2nd Battalion, 531st Engineer Shore Regiment, at Port-aux-Poules, Algeria, and was activated as the Fifth U.S. Army Invasion Training Center. On the logistical side the center afforded training in loading and unloading vehicles and personnel from various types of landing craft. By the end of May 1943 it had trained many units for the Sicilian invasion, including those of the 1st Brigade.
Planning for the Sicilian invasion (Operation HUSKY) was far more complete than for TORCH and was built on a much sounder foundation. Units were better trained and there was better equipment. In one way the operation was to resemble the later OVERLORD operation much more closely because it was to be made across a short stretch of sea, and was not launched from such widely separated points as was TORCH, for which one task force had to cross the Atlantic. HUSKY was also to be a landmark in the development of amphibious logistic support, both in far-shore organization and in equipment. For the first time a naval beach battalion was utilized to achieve closer coordination between the Navy afloat and the Army ashore. In addition, the make-up and responsibilities of the amphibian brigade emerged more clearly.
Through most of the winter the 1st Engineer Amphibian Brigade had existed in name only, its units scattered and performing a variety of duties. Their assignments included unloading cargo, operating
smoke pots, running quartermaster depots, and constructing warehouses. The organization was now redesignated the 1st Engineer Special Brigade and was quadrupled in size for the purpose of operating four beaches and a large beach maintenance area. Three engineer combat regiments in addition to the 531st Engineer Shore Regiment were attached and used as the basis of engineer regimental beach groups, each of which was attached to a combat division. The regimental beach groups in turn were broken down into battalion beach groups, each placed in support of an infantry or armored regimental combat team for the landings. With all its attached and assigned units, the 1st Brigade numbered about 20,000 men for the Sicilian operation.7
The operation was not without its errors, and new flaws appeared which called for correction. Moreover, elation over the success of the landing was tempered by the realization that the lack of resistance was to a large extent responsible. Observers cautioned that the standard of training would have been severely tested had there been strong opposition on the beaches. HUSKY had also had the advantage of tideless water, a condition which would not favor an operation in the English Channel, where tides of twenty to thirty feet had to be reckoned with. Nevertheless, from the standpoint of supply the Sicilian operation was a gold mine of experience. Once more it underscored the importance of a highly developed beach organization. As one observer remarked, the faster an army intended to advance and the more violent the blows it desired to strike, the larger must be its administrative tail. Only by the quick establishment of a logistic base could the combat forces develop their full striking power, and in an amphibious operation, it was concluded, the organization of such a base required the establishment of the beach group with its essential components.8
The Sicilian operation also provided a good test of landing craft. LCTs were used more extensively than ever before and, in general, performed well, although defects in some types were discovered. An innovation that proved very useful was the U.S. Navy’s ponton causeways—easily assembled piers used to unload all types of smaller craft. They were used so successfully that they became standard equipment for all future operations of a similar nature.
Perhaps the two most noteworthy revelations of the operation were, first, the feasibility of operating beaches over an extended period of time and, second, the success of a new piece of equipment—the DUKW. Until the Sicilian operation it was doubted whether open beaches could be used for an extensive period without deteriorating. The HUSKY experience proved this fear groundless by showing that they would not cut up and deteriorate under intensive use. Even relatively poor beaches proved capable of being efficiently used with certain engineer improvisations. This was a welcome revelation in view of the extensive use of beaches which would have to be made in the cross-Channel operation.
The success of the DUKW was phenomenal. Essentially the DUKW was a 2½-ton 6x6 truck chassis with a boat hull, propeller, and rudder enabling it to operate with about a 5,000-pound load in moderate sea and surf. The first shipment of these amphibians had arrived in North Africa in April. Experienced operators accompanied
Column of DUKWs, during training exercise off Cornwall
them and set up a school that trained a thousand men to operate them. The amphibians were used for many purposes, including some not intended. They carried stores far inland to forward dumps, evacuated casualties and prisoners, and in at least one emergency were used to transfer a Ranger battalion to meet a sudden enemy counterattack. Their versatility was immediately recognized, and heavy demands were made on them, with the result that they were frequently overloaded and misused. Lack of maintenance equipment and spare parts also contributed to their rapid decline in efficiency. But they demonstrated their usefulness in a hundred ways and proved themselves one of the most valuable “weapons” in the Allied arsenal. From HUSKY on no landing operation was to be attempted without them.9
Two later amphibious operations in the Mediterranean gave additional experience to American units in logistical operations. These were Operations AVALANCHE (the southern Italy landings of September 1943) and SHINGLE (the Anzio assault of January 1944). The southern Italy invasion contributed relatively little to amphibious doctrine or techniques. There were few major supply difficulties in the operation of the beaches, and because the ports were opened early the importance of the beaches declined rapidly after they had served their initial usefulness. Additional uses were found for the DUKW, but otherwise there were no true innovations. The Anzio operation contributed little more to amphibious doctrine except to underscore the practicability of long-term operation of beaches. The prospects for the success of operation SHINGLE were gloomy for several reasons, among them the reported inadequacy of the beaches. But from the standpoint of supply the operation actually far surpassed the hopes of the planners, thanks largely to an unanticipated development—the quick restoration of the small port of Anzio, which the Navy had thought worthless. The 540th Engineer Combat Regiment developed the port’s discharge capacity to the wholly unexpected figure of nearly 8,000 tons per day at the end of March.10 The operation therefore produced the very significant realization that the performance of small ports might be improved tremendously, a possibility which had been minimized heretofore.11
Although conditions in the Mediterranean may have differed in many ways from those in the English Channel, and although none of the Mediterranean operations served as an exact model for the later cross-Channel undertaking, North Africa, Sicily, and Italy provided a school of practical experience in which to test amphibious equipment, planning, organization, and training. Out of these proving grounds came the basis for much of the planning conducted in the United Kingdom for OVERLORD, and a number of the units that were later to participate in the Normandy invasion gained invaluable experience.
The Training Schools and First Exercises
During the period of the Mediterranean operations developments in the field of amphibious operations were of course taking place in other areas as well. In the Pacific smaller but important landings were being carried out, and in the zone of
interior training developments were also to have their influence on amphibious doctrine and practice. Direct exchange of information and personnel between the European and Pacific areas was rather negligible, although there was correspondence between the two, as for example between the 1st Engineer Special Brigade in Europe and the 2nd Brigade in the Pacific. Several key officers who had taken part in the Aleutian Islands landings, among them Col. Benjamin B. Talley, later to command the OMAHA Beach organization for a time, were brought to London to assist in cross-Channel planning.
More evident was the effect of courses, given in the United States, where several agencies were engaged in amphibious training. All units intended for assault missions and sent to the United Kingdom after January 1943 were given advanced training in the assault of fortified positions, much of it at the Engineer School at Fort Belvoir, Va., under doctrine developed by the Corps of Engineers.
Meanwhile, training in various aspects of amphibious supply operations was carried on at several installations. The Engineer Amphibian Command at Camp Edwards continued to train shore service parties and boat crews, and developed techniques for shore-to-shore movements. At Fort Pierce, Fla., and later at Camp Pickett, Va., specialized instruction was given to engineer units under the direction of the Amphibious Force, Atlantic Fleet. These experiments and exercises usually involved an engineer combat battalion with attached service troops in support of a regimental combat team. At first there was no specialized equipment and little conception of the use to which the service troops were to be put. The 1116th and 1119th Engineer Combat Groups (later designated the 6th and 5th Engineer Special Brigades respectively) received training on this pattern, which was quite unlike anything later attempted in the Normandy invasion. Both groups regarded the principles they were taught as unsound and set about developing a new solution, similar to the battalion beach group idea developed for the Sicilian landing. In addition, experiments and training were conducted at Fort Pierce by several engineer combat battalions in the destruction of underwater obstacles, which was expected to be one of the most hazardous of all invasion tasks. Schools were also set up in the United States for the training of DUKW operators and mechanics.12
The sum of most of this experimentation, training, and actual practice was eventually gathered together and applied in the United Kingdom. Little specialized training, amphibious or otherwise, was given American troops in the United Kingdom until late in 1943, however, since the policy had been laid down that training in the overseas theater should be held to a minimum. For various reasons it was felt that all specialized training should be given in the United States, and the ETOUSA G-3 specifically announced in July 1943 that the theater would proceed on the assumption that troops arriving in the United Kingdom had been properly trained before their departure from the United States. But the pronouncement of such a policy was no assurance that it would be followed, or that any reliance could be placed on its assumption regarding the adequacy of the training of units shipped from the United States. The need for specialized training facilities in the theater became evident as early as 1942.
Units could not be shipped back to training centers in the United States for retraining there. As invasion plans progressed, therefore, and as new equipment became available, new techniques were learned, and the specific requirements of the invasion tasks were defined, it became increasingly obvious that the theater would have to conduct its own specialized training.13
The first step in the establishment of such specialist training in the United Kingdom was taken in 1942 when the American School Center was organized. The theater commander at first authorized the Commanding General, SOS, to set up two separate schools, one for the training of officer candidates, the other for specialized training which had been neglected in the United States or forgotten through disuse. After the inspection of several possible sites, the Officer Candidate School and the Supply Specialists School were activated at Shrivenham, in Berkshire, where modern barracks, conference rooms, drill and recreation areas, and space for expansion were available. Col. Walter G. Layman was named commandant. The two schools were to accommodate 250 students at one time. They began their activities late in 1942 and later were combined and redesignated the American School Center.
The Officer Candidate School was designed primarily to train men whose professional qualifications fitted them for direct commissions, but who lacked the necessary military background and training. Other men, not qualified for direct appointment, had to be sent to officer candidate schools in the United States. The Officer Candidate School at Shrivenham operated for only about one year. In April 1943 Headquarters, ETOUSA, announced that officer requirements had been met, and the school was discontinued in September.
The Supply Specialists School, which had a longer life, planned courses in such miscellaneous subjects as fire fighting, motor transport, radio operation, mess management, medical field service, counterintelligence, and unit administration. In the spring of 1943 the school was removed from SOS direction and placed under the direct control of the theater commander. Late in the year General Devers ordered the school to give first priority to civil affairs instruction, and the school was expanded to accommodate much larger classes. In May 1944, just before the invasion, instruction was being given in eighteen courses, ranging from a few hours to thirty days in length. In the meantime Colonel Layman, the director of the school, had assumed additional duties as chief of the Field Force Replacement System. In the last weeks before the invasion the school was gradually transformed into a ground force replacement training center and devoted itself almost exclusively to the training of limited-assignment personnel. While the Supply Specialists School did not offer any specialized training in amphibious operations, it had some influence on various supply and service functions common to the coming beach operations and on other normal supply operations. Both the Supply Specialists School and the Officer Candidate School were later established on the Continent.14
Of more significance to the logistic preparations for OVERLORD was the training given to Allied officers in administrative planning. British and American officers were poorly acquainted with the
planning procedures in each other’s forces. This deficiency was particularly noticeable at the staff level, where a high degree of coordination and understanding was necessary in the planning of joint operations. The lack of mutually understandable procedures was sharply evidenced in the confusion attending the planning of the North African invasion. To solve the problem the Commanding General, SOS, in October 1942 requested the theater commander’s approval of a plan to establish a joint British-American “Q” school, the objective being to form a reservoir of trained American and British administrative officers who were thoroughly familiar with each other’s staff procedures and who would thus be better equipped to work together in the detailed planning for the eventual cross-Channel operation. The name Q school derived from the British Quartermaster General or Q staff, which was the equivalent of the G-4 on U.S. staffs, and indicated that the field of study would be logistic planning.
Approval was at first requested only for an experimental trial course to determine its practicability. With such approval granted, General Lee completed arrangements for the school with his opposite number, General Riddell-Webster, the British Quartermaster General. Col. George A. Lincoln, a former West Point instructor and Rhodes scholar, and Brigadier R. A. Riddell of the British Quartermaster General’s staff were designated co-directors. They carried out the detailed work on the curriculum and actually launched the courses. The idea of the Joint Q Planning School was to have a special significance for logistical planning, for, while both operational and administrative problems were to be considered, the course was to be devoted primarily to the study of administrative problems arising out of the planning and organization of combined amphibious operations. This entailed also the study of the organization, staff duties and procedures, and maintenance systems of the two Armies.
The experimental courses were held from 5 to 12 December 1942 in the British General Staff College at Camberley. Both British and American staff officers served as instructors, and officers from both armies attended the courses. So confident was General Lee that the justification for the school would be borne out by the experimental course that he meanwhile drew up plans for establishing the school on a more permanent basis. By the time the final plan was outlined (January 1943) the Camberley experimental courses had been given and General Lee could state that they had been sufficiently successful to justify the continuation of the school.
The Joint Q Planning School opened on a more permanent basis on 25 January 1943 at Norfolk House, St. James’s Square, London, with a ten-day course for thirty officers, half of them British and half American.15 Key officers in the SOS staff sections and services and representatives of the Eighth Air Force were directed to attend the first course. The school was placed under the joint supervision of the British Quartermaster General and the Commanding General, SOS. Subjects initially studied included staff procedures, preliminary planning for an amphibious operation, landing tables, mounting, beach maintenance, maintenance problems of the assault and later stages, civil administration, and a host of other problems. These subjects were grouped into three general categories and the course
was presented in three parts: (1) a comparison of the organization of the British and American Armies, with emphasis on functioning of supply services and administration; (2) background of planning, ships and craft, beach organization, naval and air aspects of overseas movement, mounting, far-shore brigades, division of Army and Navy functions, and civil administration; and (3) planning methods for an amphibious operation, including scales of equipment and maintenance, loss estimates, special features of operations in northwest Europe, and specimen directives.
From the very beginning the school operated on the assumption that it was preparing for the invasion of France, and in the year during which it functioned it was a most important training organization for officers who participated in the OVERLORD planning. Changes were made from time to time as new techniques were developed or new topics became more apropos, and as specialists became available as instructors. The program evolved into a series of twelve-day courses, and classes grew in size to about seventy officers, half British and half American, and most of them of field grade. Both SOS and Headquarters, ETOUSA, sent officers to the school, the SOS allotment being distributed to the staff, services, and base sections, and the ETOUSA allotment being made up from theater headquarters, the air forces, and the field forces. In the year between January 1943 and January 1944, when the last course was offered, 460 American officers attended the school. Most of the officers who took the courses either held key positions or played active roles in the various planning agencies and in the staffs of units which were scheduled to assault the Normandy beaches and establish supply installations on the far shore.16
The training afforded by the American School Center and the Joint Q Planning School was initiated in what may be roughly termed the early training phase. In this period, from the activation of the theater in June 1942 to the fall of 1943, there were relatively few American combat or amphibiously trained supply units in the United Kingdom, for the big buildup had not yet begun. Consequently, until the fall of 1943 invasion training was largely a matter of experimentation involving British units and the 29th Infantry Division, the only large American ground force combat unit stationed in the United Kingdom for many months after the departure of units for North Africa. In many respects the 29th Division was a sort of trial horse for training methods. It carried out a rigorous training program, which included trying new assault methods, amphibious landings, testing new equipment such as amphibious tanks, and new techniques such as the waterproofing and swimming of vehicles. This experimentation had its primary effect on later training of combat units, and had only an incidental or indirect bearing on supply operations. Special courses, such as those conducted by the Engineer School at Wallingford, in Oxfordshire, had a more direct influence on logistics. Supply problems received more attention in the various exercises which were held throughout this early period. These exercises were a vital stage in the development of both tactical and logistical doctrine as later applied. Most of them were experimental in nature and were designed more to develop and test techniques than to train troops.
Most important of the early exercises from the point of view of amphibious operations and also in the development of supply practices were two known as JANTZEN II and HARLEQUIN. The first of these was held by the British Western Command in the Carmarthen area of southern Wales in July 1943. The purpose of JANTZEN II was to practice the maintenance of a corps and supporting troops over beaches for a period of two weeks. It involved the movement of troops from concentration areas through assembly and transit areas, embarkation, the loading and unloading of coasters, the organization of beaches and a beach maintenance area, the establishment of a bulk fuel supply installation, and so on. Only administrative and supply troops took part, and there was as yet no special amphibious equipment, but the exercise produced valuable information on staging problems and on the whole matter of supply maintenance in an amphibious operation.
Even more important was Exercise HARLEQUIN, held early in September under the direction of the Commander-in-Chief, 21 Army Group, and the commanders of the First Canadian and Second British Armies. HARLEQUIN was actually part of a larger deception scheme planned for the summer of 1943, and therefore had several purposes. Most useful from the point of view of training for the later cross-Channel operation was the testing of mounting procedures—that is, the machinery to move troops from concentration or assembly areas through marshaling camps to embarkation points. Complete landing tables were worked out, and the bulk of the forces involved moved to assembly areas, formed into craft loads, and then moved to embarkation points. Only a small number of vehicles were actually loaded, and the bulk of the troops returned to their stations without embarking. Exercise HARLEQUIN was held along the south and southeast coast of England, where mounting installations, including concentration areas and reception and marshaling subareas, were established. American officers participated only as observers, and learned a great deal about the mounting procedure and about housekeeping problems in the concentration and marshaling areas. Perhaps more significant was the basic change in planning concept which the exercise produced regarding movement and loading. HARLEQUIN revealed that, contrary to previous opinion, the loading of assault forces, even though preplanned, was much more difficult a problem than the loading of build-up forces. The exercise thus had a direct bearing on the estimated needs of mounting and loading facilities.
JANTZEN II and HARLEQUIN were British exercises and were only two of several held in 1943. American units participated in many other exercises designed to test specific doctrines or solve particular problems. These practice operations dealt with such varied problems as communications, the use of smoke, the training of naval forces in combined operations, embarkation, and turn-round of shipping. All had their influence on invasion planning and later training of American units, although the results were hardly definitive.17
The Assault Training Center and Engineer Special Brigades
Training activities between the fall of 1943 and the date of the invasion fall roughly into four categories: the highly
specialized training given to assault units and beach engineers; the minor exercises used to test portions of the OVERLORD plan; the training program worked out by the various assault units themselves; and the major exercises or dress rehearsals held just before D Day. Neither the many minor exercises nor the independent training programs of the various units are within the province of this volume. Space limitations prohibit a detailed description of the many specialized exercises; as for unit training programs, which were undertaken by nearly all American units in the United Kingdom, they had no special bearing on the unusual problems connected with the assault, for in most cases they followed training instructions as laid down in the manuals and were a continuation of training given in the United States. Of more particular significance were the highly specialized training given the assault units and beach brigades, and the big dress rehearsals immediately preceding the invasion.
In view of the type of resistance expected at the Atlantic Wall, which bristled with steel and concrete, it was evident that assaulting forces would need special training and organization. This realization eventually led to the establishment of the most important U.S. invasion training center in the European theater—the Assault Training Center. Its establishment was the direct result of steps taken as early as 1942, when an American section was set up in the British Combined Operations Headquarters. Arrangements to attach such a staff to the Chief of Combined Operations had been made after General Marshall’s visit to England in April 1942. Col. Lucian K. Truscott, Jr., who as a lieutenant general later commanded the Fifth U.S. Army in Italy, was selected to head the section, its principal mission being to study and report on the conduct of combined operations and to provide battle training for as many American troops as practicable. The section was established in May, and in the succeeding months U.S. Rangers trained with British units in commando tactics.18
The training of U.S. assault units eventually took a different form, however. Americans participated in British combined operations training on the assumption that the training of assault units for the cross-Channel operation would in general follow the principle of Commando and Ranger training. Before long it was realized that this would not be the case. Rangers were selected, trained, and equipped for special missions, usually striking swiftly and then returning to their base. Assault troops in the invasion were to be normal infantrymen, organized on a division basis, and were to remain ashore for sustained offensive action after the capture of a beachhead. In the winter of 1942–43 thinking on this matter had advanced to the idea of an independent assault training center. The ETOUSA G-3 Section, under General Barker, had in fact made plans for the establishment of such a training center and took steps to obtain an officer to head the project. Late in January 1943 Lt. Col. Paul W. Thompson of the Office of the Chief of Engineers, War Department, was transferred to the European theater and a few weeks later was assigned to the G-3 Section to take charge of the new project. Described by General Lee as “our best informed engineer officer on German organization, technique and tactics,” Colonel Thompson
was a logical choice for the assignment. He had been trained as an engineer, had served with a German engineer battalion and studied hydraulic engineering at the Technische Hochschule in Berlin-Charlottenburg, and had served with the Intelligence Branch of the Office of the Chief of Engineers. His assignment foreshadowed the large role which engineers were to play in the invasion.
Meanwhile members of the ETOUSA G-3 Section began a search for a training area large enough to accommodate regimental combat teams and possessing shore and beachhead terrain generally similar to that of northern France. After inspecting several locations they finally chose an adaptable site on the western coast of Devon between the towns of Woolacombe and Appledore. The area embraced 25 square miles of land, 8,000 yards of beach on the Bristol Channel, and 4,000 yards on the Taw estuary. (See Map 6.) Inspecting officers noted several disadvantages, but in general the area had the characteristics of the northwest French coast, including the vitally important tidal range which was absent in the Mediterranean landings. It was thought at first that the area would not have to be evacuated, even though about 10,000 acres of farmland were taken from cultivation. The limitations in space meant that all firing would have to be tightly controlled. It later became necessary to move some of the civilian population for reasons of security and safety. The Assault Training Center was activated on 2 April 1943, with Colonel Thompson named as commandant. Target date for the opening of the center and the start of training was set for 1 September.
The Assault Training Center was placed directly under Headquarters, ETOUSA, and its activities were coordinated with the G-3 Section, which was responsible for training. The center’s over-all mission was to develop the special tactics and techniques necessary for an assault of a heavily defended shore and to train units to be employed in such an operation. This involved not only the development of assault doctrine and workable methods for the assault of enemy-held shores, but the training of demonstration troops, the staging of demonstrations of approved techniques, and the instruction and supervision of all assault units expected to participate in the operation. For this purpose the center was to assemble and organize a special assault battalion combat team to act as a test unit. It was assumed that all units training at the center would have had either basic amphibious training in the United States or training similar to that of the 29th Division in the United Kingdom, or actual battle experience in the Mediterranean.
In some respects the center began from scratch as far as amphibious techniques were concerned. At the time of its activation in April only the limited lessons of the TORCH landings were at hand, and TORCH showed little resemblance to the type of landings envisaged in the cross-Channel operation. To begin with, the Americans relied heavily on British experience in formulating the training program, and the center was authorized to establish liaison with both British and American agencies in the field and with British Combined Operations Headquarters. That assault techniques were in the formative stage is indicated by the many discussions and proposals initially put forth on the subject of the organization and arming of assault units, some officers recommending that special assault divisions
and assault regiments be formed, others recommending that the normal battalion structure be retained but that special assault platoons be constituted. General Noce, who had organized the Engineer Amphibian Command in the United States, had an active part in these early decisions as the new ETOUSA G-3.
The organization of the center and the writing of specific plans for its operation received additional impetus from the RATTLE Conference of late June, where the need for assault training was again noted. By the end of July considerable progress had been made in formulating a training program. Assault unit organization was tentatively agreed to, plans were made for the construction of full-scale German-type beach obstacles and fortifications, obstacle courses, and combat ranges, and arrangements were made for the Navy to provide landing craft and to participate in the preparation of training schedules and field exercises. By mid-August the center had moved from its temporary headquarters in Grosvenor Square, London, to Woolacombe, and work was pushed on the new quarters and on the various assault and firing ranges and courses. Five administrative divisions were set up, including a headquarters and staff, a station complement, a school troop section, an assault training section, and an amphibious section. The amphibious section was to organize training for the purely amphibious phase of operations, from embarkation to landing, while the assault training section was responsible for operations after the touchdown on the beaches. School troops were to provide task forces and combat teams for demonstration and for the development of tactics, for controlling and umpiring exercises, simulating enemy forces, and so on. Early in August the 156th Infantry arrived at the center to assume these duties, testing various techniques developed by planning officers, and later demonstrating them and instructing other units.19
Training at the center was organized mainly with the combat units in mind, and was concerned primarily with such matters as the development of the most effective assault team, the best combination of weapons, the use of tanks, and the best techniques to overcome coastal fortifications, although the logistic aspects of amphibious operations also received attention. Beginning in September 1943 the 29th, 28th, and 4th Divisions, and a portion of the 1st Division, despite its battle experience in the Mediterranean, all completed the training course at the center. The 2nd and 5th Ranger Battalions and parts of the 101st Airborne Division also took the courses, as did specialized artillery, antiaircraft, chemical warfare service, quartermaster, and engineer units which had missions in the assault. All units were rated on their performance. Training was hard, and a number of accidents occurred, as could be expected in exercises which included the use of live fire. But the need for realistic training undoubtedly justified the risks.
More important for the logistic aspects of the invasion operation was the training given the engineer brigades which were scheduled to organize the Normandy beaches for supply. The infantry participation in the amphibious phase of the operation would be limited to a few hours;
the engineer brigades were to perform service functions for an indefinite period. The 1st, 5th, and 6th Engineer Special Brigades all were given specialized instruction at the Assault Training Center, and were among the most highly trained of the invasion units.
Each of the three brigades consisted basically of three engineer combat battalions, a medical battalion, a joint assault signal company, a company of military police, a DUKW battalion, an ordnance battalion, and various quartermaster units, numbering 4,000-odd men. But eventually all three were built up to a far greater strength. The 1st Brigade was transferred to England in December 1943 with only 3,346 men. In the OVERLORD operation it was assigned the mission of supporting the VII Corps and organizing UTAH Beach, and in the spring of 1944 its strength was greatly augmented by the attachment of a large number of units. These included quartermaster service companies, TC port companies, military police escort guard companies, and several small special units, some of which were to land well after D Day and required no special amphibious training. By the time of the invasion the brigade again had a strength of over 15,000.
A considerably larger and more complicated organization was evolved for OMAHA Beach. OMAHA was to have the important MULBERRY installation and was to develop a substantially larger discharge capacity than UTAH. Two brigades—the 5th and 6th—were therefore formed to handle the larger volume of supplies in support of the V Corps. Both the 5th and 6th Brigades were newly organized from engineer units which arrived in the United Kingdom in the winter of 1943–44. Shortly after the 1119th Engineer Combat Group arrived in November 1943, it was designated the 5th Engineer Special Brigade and began the process of building up to invasion strength in the same manner as the 1st Brigade. The 1116th Engineer Combat Group arrived in January 1944, was immediately redesignated the 6th Engineer Special Brigade, and its strength was similarly augmented by attachment of the necessary units. Both groups had had amphibious training in the United States.
In view of the large supply organization envisaged for OMAHA Beach, engineer planners of the First U.S. Army recommended the organization of an over-all headquarters to provide a unified command at OMAHA. Plans for it were drafted in February 1944, and First Army headquarters immediately authorized the grouping of the two brigades under one command. The final form which the OMAHA supply organization would take was not immediately clear, but in March the new headquarters was formed, using personnel from both brigades, First Army, and V Corps, and was named the Provisional Engineer Special Brigade Group.
Group headquarters eventually became an organization far beyond the size originally contemplated. The idea of a small, compact headquarters, concerned primarily with planning, was gradually abandoned as the demands of the job made apparent the need for a much-expanded organization. In the course of the planning it was realized that the two brigades by themselves would not be able to handle the OMAHA supply operation, which included not only the organization of supply over a wide beach, but the operation of an artificial port with a discharge goal of 5,000 tons per day, and of two minor ports (Grandcamp and Isigny). To
meet these latter needs the 11th Port, which had been operating the Bristol Channel ports, was attached to the group in April. The 11th Port, numbering more than 7,600 men, included four port battalions, five amphibious truck companies, three quartermaster service companies, three quartermaster truck companies, an ordnance medium automotive maintenance company, and a utility attachment. By D Day the entire Provisional Engineer Special Brigade Group, with all its attachments, had a strength of nearly 30,000 men.20
While the Assault Training Center was set up primarily to develop assault techniques and train infantry combat units, it provided an important training ground for all three of the engineer special brigades. The 6th Brigade carried out the most strenuous program, ending with two beach exercises for groups of 1,600 men. These included landing, setting up dumps, clearing beaches, and constructing exits. This training was conducted largely under the direction of officers from the brigades themselves, employing their own school troops. In November 1943 the 234th Engineer Combat Battalion had been assigned to the center for the training of other engineer units. This battalion maintained beaches, gave indoctrination lectures and demonstrations, and assisted in exercises employing engineer brigades in the organization of beaches, preparation of exits and dumps, maintenance of road nets, preparation of traffic plans, salvage of drowned vehicles, and movement of supplies. For the training of the beach organization, therefore, the center was to a large extent actually organized as a far-shore beach, with the 234th Engineer Combat Battalion carrying on the functions of a far-shore brigade and assisting in the training of engineer units for their mission on the Normandy beaches.
Besides serving as a training ground the Assault Training Center also tested and made alterations in amphibious doctrine and techniques. In connection with supply operations, for example, new uses were found for the DUKW, and improvements were made in the use of these amphibians in ship-to-shore operations. Early in November 1943 a demonstration of coaster unloading went very badly, revealing weaknesses particularly in the stage when the DUKW was held alongside the coaster to receive cargo. In the following weeks new types of gear were devised to remedy this defect, and when the exercise was repeated a month later great improvements had been made in the transfer operation.
The Assault Training Center thus had an important role in the development of amphibious techniques and in the training of units, not only in methods of assault, but in the vital beach supply operations, on which the OVERLORD operation was to be so dependent. Thousands of troops were run through one or more of the courses at the center, and by the end of April the major portion of the center’s training was completed. As the invasion date neared, key personnel at the center were gradually recalled for assignments in units with missions in the assault. Colonel Thompson was given a new assignment early in March, and in the next two months there followed several changes in command. On 1 May the buildings and training areas were, with a few exceptions, turned over to a Field Force Replacement Depot, and on 15 May the center was officially deactivated.
Major Exercises
While the Assault Training Center offered specialized training to assault formations and beach organizations, the Allies were holding a series of exercises that constituted a second major category of training. Beginning in January 1944 and continuing until marshaling for the invasion itself began, an almost unbroken succession of such exercises took place, two or more often being conducted simultaneously. There was, first of all, a series of very specialized exercises involving relatively small numbers of troops of one type. These were mainly of the technique-testing variety, the details of which cannot be described here. More important from the point of view of training in the coordination of combined arms and services were the large scale exercises and final rehearsals. The major exercises—known as DUCK I, II, and III, FOX, and BEAVER—brought together all elements of a force in a combined assault and supply action, including all phases and aspects of the mounting and launching of an amphibious operation, Finally, two big dress rehearsals—named FABIUS I and TIGER—attempted to duplicate as nearly as possible the conditions expected in the cross-Channel invasion.21
Of the major exercises DUCK I was probably the most important. It was the first attempt to bring together the various arms and services in a coordinated amphibious operation approximating the conditions of the later assault. Being the first, it revealed many defects, and their elimination greatly affected the training and planning for the exercises which followed. Exercise DUCK I was first conceived as a mounting exercise for the Services of Supply, and was discussed as early as the summer of 1943. Later its scope was extended to cover all phases and aspects of an amphibious operation, and the actual planning of the exercise was begun early in November. The final decision to hold the exercise was made later in the month by representatives of V Corps, SOS headquarters, the Navy, Southern Base Section, XIX District (a subcommand of Southern Base Section), the British Southern Command, and the British Southwestern District. Because DUCK I was to interfere as little as possible with either the preparations or the facilities of OVERLORD, the Slapton Sands area, a few miles southwest of Dartmouth, was selected as the site of the exercise. Although this thinly populated area, relatively removed from the BOLERO and OVERLORD installations, had some disadvantages, it bore a general resemblance to the Normandy coast, even possessing a lagoon separating the beach from the mainland, approximating the features of the UTAH area. (See Map 6.)
Participants in the exercise were to include a regimental landing team built around the 175th Infantry (29th Division), units of the 1st Engineer Special Brigade, and such attachments as a Ninth Air Force beach party and a headquarters group from V Corps. The Services of Supply was to provide the mounting installations and the supplies and equipment replacements in coordination with V Corps, and was responsible for the marshaling and embarkation of units. As in the later OVERLORD operation, this responsibility was delegated to Southern Base Section, and the latter in turn delegated the task to XIX District, the area in which the exercise was to be held,
although Southern Base Section staff officers aided in the planning and execution of the service functions. Troops were to move from their camps near Plymouth, Taunton, Barnstaple and Land’s End to embarkation points at Falmouth and Dartmouth. The 11th Amphibious Force was to move them from the embarkation points to the assault beach at Slapton Sands with the help of British naval units and protect the convoy from enemy attacks, and the Ninth Air Force was to provide air protection. To give additional training in the mounting process, troops of the 28th Division were also to be processed to the embarkation points, and then returned immediately to their stations without actually boarding craft.
The detailed planning of the exercise began late in November when the DUCK I staff held its first meeting at XIX District headquarters near Taunton. The administrative and tactical headquarters involved, XIX District and V Corps, respectively, worked closely in formulating the plan, and the first steps in the implementation of the plan were taken immediately. The exercise was to be of immense value to the Services of Supply because for the first time the whole mounting procedure was to be tried out in a coordinated operation. The SOS was to have the primary responsibility in the eventual mounting of Operation OVERLORD, and its activities in this phase included planning, constructing housekeeping installations, assembling troops and supplies, marrying the auxiliary units to their respective combat teams, processing troops through the marshaling areas, moving them to the embarkation points, loading the landing craft, loading and dispatching coasters, and transporting and feeding troops on their return to their home stations. More than 10,000 men made up the assault force in the exercise, and approximately an equal number were involved in performing the SOS functions.
D Day was originally set for 3 January 1944. On D minus 10 the loading of coasters was begun at Bristol. The movement of troops and vehicles to assembly areas began on D minus 8. LCTs began loading on D minus 6, LSTs on D minus 4, and LCI(L)’s on D minus 3, which was 1 January. At this time H Hour was definitely set as 1000 hours, and D Day was changed to 4 January. Including the assault troops that cleared the marshaling areas and embarked and the 28th Division troops that moved through the various mounting stages, a total of 26,400 men were marshaled.
The assault phase proceeded largely as scheduled, although the landings did not go entirely according to plan. Considerable trouble was caused by the runnel that separated the beach from the mainland, for bridging equipment failed to arrive on time. But in general the landings were smooth, with assault troops, following a pre-H-Hour bombardment, storming simulated enemy defenses and pushing rapidly inland. Most important from the supply standpoint were the experiences of the 1st Engineer Special Brigade. Brigade troops began landing at D plus 25 minutes, demined one beach, cleared a second, set up three supply beaches, opened beach exits, and began unloading supplies. Coasters began arriving within a few hours and were unloaded by DUKWs and landing craft, and dumps were then established inland. Engineers tested methods of track laying to improve beach roads and tried new packing and waterproofing methods. Quartermaster units experimented with pallet loading, and the Signal
Corps tested skid loading and new packaging methods.22
The exercise lasted two days, after which the mounting process was reversed and troops were returned to their home stations by XIX District. In the meantime observers completed their note taking, and a series of critiques followed. As could be expected in a first trial, errors and deficiencies aplenty were found. Criticisms were directed at varied weaknesses, from poor Army-Navy coordination and inadequacy of planning to poor traffic control and discipline, slow movement, overloading of both troops and vehicles, and violations of security.23 The inexperience of many of the 1st Engineer Special Brigade units was clearly demonstrated. The brigade commander, Col. Eugene M. Caffey, took special note of this, emphasizing the need of the brigade to build up its internal structure and to coordinate more closely the work of its heterogeneous units. More specifically, the unloading of LCTs had taken double the time planned, loading priorities had been difficult to follow, and stowage plans had failed to arrive for unloading crews.
For a first attempt the exercise had actually come off quite smoothly. The marshaling procedure, which will be described in more detail in the next chapter, worked so well in DUCK I that it formed the basis for the mounting of all later exercises and for the invasion operation itself. An improvisation had been adopted which proved most effective. British authorities had objected to the holding of large-scale exercises on the southern coast because of possible damage to hardstandings, the areas scheduled for later use as vehicle parks in the mounting of OVERLORD. Many of these could be used only a short time, for the turf was easily torn up and the areas might quickly turn into quagmires. If used prematurely, they would hamper the later mounting of the invasion. To avoid this danger Col. Theodore Wyman, Jr., commandant of XIX District, evolved a plan in which marshaling areas were built along secondary hard-surfaced roads. Camps were established in wooded areas along the edges of the roads, and the roads themselves were blocked off to civilian traffic and used as hardstandings. Because of their elongated shape on maps these areas came to be called “sausages.” Hardstandings intended for the OVERLORD mounting were thus saved, and the success of the plan made other exercises possible and also provided a means of supplementing the marshaling installations in the OVERLORD operation.
One result of the DUCK I critiques was the establishment of a permanent planning group for exercises, and after the last critique late in January this group immediately set about planning additional tests. Two sequels to DUCK I—known as DUCK II and DUCK III—were scheduled for February. They were intended to give experience to units in both the 29th Division and the 1st Engineer Special Brigade which did not participate in the first exercise. D Day for DUCK II was finally set for 14 February. Movement tables were published on the 7th, and movement of the
task force personnel into the assembly area began two days later. Some units moved directly from their home stations to the embarkation points. Loading was completed on 12 February, and the assault was carried out on the 14th and 15th. DUCK III followed the same general pattern, with the D-Day assault coming on 29 February.
In most respects these two exercises went off more smoothly than DUCK I, although the principal problems encountered were much the same as in the first exercise. There still were difficulties over traffic control, over coordination between the services, and over the Navy’s handling of craft. Although the three DUCK exercises gave training to most of the units of the 29th Division and the 1st Engineer Special Brigade, these two organizations did not team up in OVERLORD. The 1st Brigade eventually supported the 4th Division at UTAH Beach, and the 29th Division was supported by the 6th Brigade at OMAHA.
A fourth exercise held in March more closely paralleled the final OVERLORD assault plan. This was Exercise FOX, the last big training exercise before the final rehearsals. The initiator again was V Corps, which ordered the planning to begin early in February. Since the exercise was intended to be modeled on the OVERLORD operation, detailed planning was held up so that it could parallel the work on OVERLORD, and did not get under way until the First Army Operation Plan NEPTUNE was published late in the month. The exercise suffered somewhat from the resultant tardiness and once more pointed up the vital importance of adequate planning.
Exercise FOX was held at Slapton Sands, but the mounting of the exercise was this time accomplished by XVIII District and involved entirely different personnel and camps. Tactical units taking part were the 16th Regimental Combat Team (1st Division) and the 116th Regimental Combat Team (29th Division), operating in turn under the commands of the 1st Division and V Corps. The two teams were to be supported by engineer combat battalions from the 5th and 6th Engineer Special Brigades. Each of the battalions was reinforced with DUKW and truck companies, medical and signal detachments, and quartermaster and port troops to comprise a battalion beach party. The makeup of the assault force therefore bore a strong resemblance to that of the V Corps in Operation OVERLORD, although on a smaller scale.
By the time Exercise FOX was planned the mounting procedure was quite firmly established. Units moved to marshaling areas according to a schedule and began embarkation at the ports of Plymouth, Weymouth, Dartmouth, and Portland on 7 March. Nearly 17,000 men and 1,900 vehicles were processed through the system and embarked on naval craft. Some of the craft, scheduled for early landings, assembled and departed for Slapton Sands the night before D Day, escorted by British destroyers. Air cover was provided by both the RAF and Ninth Air Force.
The landings took place on 9 March, preceded by naval gunfire employing live ammunition. In general, the assault was satisfactory. Its failures and weaknesses were attributable primarily to the inexperience of the units participating, although the operation also suffered from hasty planning and preparation and from the repetition of errors of the previous exercises. Coordination between the Army and Navy and between other headquarters was still faulty, and there were other difficulties of a more tactical nature. So far as
the supply and service aspects of the exercise were concerned, neither the mounting nor beach operations went off as well as hoped. The XVIII District had had insufficient time to ready the marshaling camps for transient troops, and lack of experience on the part of camp personnel was also apparent. But camp operation improved as troops gained practice. The major criticism centered about the supply operations, most of it concerning ship-to-shore movements. There had been too few loading points for the number of craft involved; there was poor coordination between the beachmaster and coasters, resulting in the delayed arrival of supplies on the beach; unloading equipment on the coasters was in poor condition, and coaster captains had no orders. Communications were generally bad between beach headquarters and the dumps. In addition, it was found that too many DUKWs had been allotted each coaster for unloading; troops were landed in the wrong order; and there consequently was improper marrying up of troops with their equipment. There were bright spots, however, and this exercise, like others, contributed its lessons and proved the value of several new techniques. One of these was the use of DUKWs preloaded with balanced loads of ammunition for emergency use. This proved so satisfactory that it was incorporated into invasion plans. Satisfactory progress was also made in the use of new methods and materials in the waterproofing of vehicles.
The DUCK and FOX exercises were all conducted by the V Corps and, with the exception of the 1st Engineer Special Brigade, involved units scheduled to land at OMAHA Beach. In order to give experience to the 4th Division assault units along with the 1st Engineer Special Brigade units which were to support them at UTAH Beach, another series of exercises was therefore planned for the last two weeks of March. Four of these exercises—named OTTER I and II, and MINK I and II—were battalion landing team tests held in the Slapton Sands area. Two exercises—MUSKRAT I and II—involved regimental combat teams and engineer detachments in battalion exercises in the Firth of Clyde in Scotland. Finally, a seventh exercise, known as BEAVER, was a combined test for two regimental combat teams (the 8th and 22nd of the 4th Division) with a large beach party from the 1st Engineer Special Brigade, plus two companies of engineers from the 1106th Group, the 502nd Parachute Infantry, and elements of the Ninth Air Force. BEAVER was directed by VII Corps and was mounted by XIX District of Southern Base Section. The force marshaled and embarked in the Brixham–Plymouth area and was then moved to Slapton Sands by the 11th Amphibious Force. The exercise was held on 27–30 March and in general followed the DUCK pattern. Assault units secured a beachhead, pushed inland, and were then resupplied and reorganized for continued operations.
In the meantime several small specialized exercises were held by artillery, antiaircraft, tank destroyer, airborne, and air force units, and by medical and signal units. Among them were also several marshaling and loading exercises having a direct bearing on the build-up and logistical support of U.S. forces. Of the marshaling exercises the most important were three called CHEVROLET, JEEP, and JALOPY. The first was carried out mainly by troops from the 5th Engineer Special Brigade and was planned and directed by XIX District headquarters. It was designed
to train troops and supply staffs in the outloading of supplies from the United Kingdom, to train chemical warfare units in screening a harbor and beach area by the use of smoke, and to test the feasibility of extended operations in a completely smoke-screened harbor and beach. The exercise was carried out in the Port Talbot and Port Eynon areas at the end of February. Exercise JEEP, conducted by XV Corps and Northern Ireland Base Section in March, was designed to give training in the mounting of build-up forces. Elements of the 2nd Division moved from their stations in Northern Ireland to Belfast and went through the entire mounting process with the exception of actual embarkation. Personnel went only as far as quays, simulated loading, and then returned. From this training experiment came several recommendations on marshaling procedures which were later adopted in OVERLORD. A third mounting exercise, called JALOPY, was essentially a repetition of JEEP, using units of the 5th and 8th Divisions, also in Northern Ireland.
Meanwhile a series of loading exercises was held, involving the 1st, 5th, and 6th Engineer Special Brigades and various SOS units under the XVIII and XIX Districts of Southern Base Section. Their purpose was simply to arrive at the most efficient loading procedures for the cross-Channel invasion. The first of the series—NUDGER—was held in December 1943 by SOS and Canadian units at Southampton. Its main object was to determine the time required to load and unload LSTs in both daylight and darkness and to determine the speed of turn-round. The results were not final, and later exercises developed speedier methods. The same problems were further tested in Exercise SNIPE in February 1944. In Exercise GULL, held in March, the loading and landing of personnel and vehicles from LSTs were also tested.
A more specialized loading exercise, called CELLOPHANE, was conducted by XXIX District of Western Base Section late in April in the Oxwich Bay area. This was an SOS exercise designed to demonstrate skid-loading techniques to the First Army. It included the loading of skid loads and loose cargo onto coasters at ports, offloading into DUKWs and LCTs, transferring loads from ukws to trucks at beach transfer points, discharging direct from DUKWs to dumps, offloading LCTs to trucks, and discharging trucks at dumps. Exercise CELLOPHANE was a comprehensive demonstration of specialized types of loading and unloading, showing the extent to which certain types of mechanical equipment, such as fork lifts, would be required. It pointed the way to the organization of transfer points as they were eventually set up at the OMAHA and UTAH beaches. In addition to these marshaling and loading exercises a number of small tests were run off by the engineer special brigades. Among them were two series, known as CARGO and TONNAGE, involving beach battalions in the handling of supplies over beaches.
Final Rehearsals
Of the major combined exercises described above—that is, the DUCK series, FOX, and BEAVER—the three DUCK exercises had been planned and carried out before the OVERLORD plan was made final and the composition of its task forces was established. The DUCK forces were therefore mixed, containing some units later scheduled for UTAH Beach, and some for OMAHA. After publication of the First
Army NEPTUNE Plan at the end of February the exercises followed the pattern of the actual invasion operation, exercise FOX involving the units of the V Corps intended for the assault on OMAHA Beach, and the BEAVER force comprising VII Corps units scheduled for the UTAH landings. These two exercises led logically to the two big rehearsals for the invasion—FABIUS and TIGER.24
FABIUS constituted a whole series of exercises in which all the assault forces scheduled to land in the Isigny–Caen area—American, British, and Canadian—were to participate. A separate rehearsal known as TIGER was to be held for the VII Corps operation at UTAH Beach. Both were “dry runs” of the actual invasion, which was to follow very shortly. They were in a sense the climax of all the long months of training and they were the most realistic and comprehensive simulations of OVERLORD which were held.
Preliminary planning for TIGER was initiated early in February 1944, but not until April were VII Corps and the SOS given definite instructions to prepare for the exercise, which was to be held late that month. Exercise TIGER was to involve all three regimental combat teams of the 4th Division and its supporting 1st Engineer Special Brigade, and was to be mounted by XIX District on the same pattern as the earlier DUCK and BEAVER exercises. Slapton Sands was again to be the scene of the landings. The assault force was to be mounted in the Plymouth–Dartmouth area, embarked in the Dartmouth–Brixham–Torquay area and at Plymouth. The 2nd Group of the 11th Amphibious Force was to provide the lift for the sea voyage. A total of 25,000 men and 2,750 vehicles was to be embarked.
The plans for the assault on UTAH Beach differed from those for OMAHA in that they included extensive airborne operations by the 82nd and 101st Airborne Divisions. In was desirable, of course, for the TIGER exercise to include the participation of airborne units in order that the exercise could duplicate as closely as possible the actual D-Day operation. The unavailability of aircraft, however, and the technical difficulties involved in making drops in the Slapton Sands area cut to a very limited scale the participation of airborne units. They took part in the exercises, but the landings were simulated by the arrival of airborne troops in trucks. This participation involved principally the 101st Division, with which the 4th Division was to establish immediate contact behind the beaches at UTAH.
Exercise TIGER was held between 22 and 30 April, with D Day on the 28th. Six of the nine days were taken up by marshaling and embarkation. As in previous exercises there were traffic jams and confusion when coordination failed and schedules were not kept. The fault stemmed partly from the late arrival of naval craft at embarkation points. In some cases loading tables had to be rewritten. But in general the mounting process showed improvement, particularly in the operation of camps, and the force was successfully embarked.
Only a few hours before H Hour a portion of the seaborne force experienced a tragic encounter with German warships, which seriously marred the build-up and supply phases of the exercise. An hour or two after midnight on the night of 27–28 April, German E-boats discovered eight
LSTs in convoy off Portland. The enemy torpedoed and sank two and caused a loss of life greater than that later suffered by units in the initial assault on UTAH Beach. At the time of the attack the LSTs were proceeding westward toward the assault area, carrying troops of the 1st Engineer Special Brigade, the 4th Division, and VII Corps headquarters, which were scheduled to participate in the build-up phase of the exercise. Little was known about the enemy except that the attack was believed to have been made by E-boats. The enemy craft launched several torpedoes, some of which failed to explode, and the Germans strafed the decks of the LSTs and fired on men who jumped into the water. Several of the LSTs escaped, although at least one later picked up survivors.
The attack inflicted its heaviest damage on supply units. Army records list 749 fatalities and more than 300 injured. Most of the casualties were from one LST, No. 531. The unit suffering the heaviest losses was the 1st Engineer Special Brigade, which listed 413 dead and 16 wounded. Other units sustaining heavy losses were the 3206th QM Service Company, which lost 201 killed or wounded of its total strength of 251, and the 557th QM Railhead Company, which suffered 69 casualties. The E-boat attack was a complete surprise, and men on the LSTs reacted in different ways. Some thought at first that it was all part of the exercise, and some even kept a sense of humor and leaped over the sides of the craft shouting “Dry run!” The attempts to cope with the emergency met with considerable confusion and disclosed a number of deficiencies in connection with safety devices and regulations.
Except for the costly run-in with the enemy the exercise proceeded substantially as planned, although build-up and supply plans were upset, and the beach party was almost reduced to its assault phase elements. Following a naval bombardment of simulated enemy defenses, 4th Division assault troops went ashore, reduced pillboxes and cut wire, and made their way inland to make contact with elements of the airborne division. Units of the 1st Engineer Special Brigade meanwhile went ashore, swept mines, opened beach exits, laid tracked roads, and established the first dumps. Supply operations were watched closely by First Army, which had ordered 2,200 tons of stores unloaded in the first two days. As scheduled, two LCTs unloaded on the first tide, two coasters on the second, and on D plus 1 the mission was accomplished with the unloading of six barges. Experiments with skid loading were again carried out and proved successful enough for some classes of supplies to be incorporated in the OVERLORD supply plan.
While the VII Corps was engaged in its rehearsal, the U.S. V Corps, the three British assault forces, and certain build-up forces carried out the FABIUS exercises. These exercises, numbered I through VI, were planned independently by the various commands concerned, but were carried out more or less simultaneously and were coordinated at the level of 21 Army Group. They were all held in the period 23 April-7 May. Like TIGER, they were patterned after the OVERLORD operation and the forces had the same general makeup as in the actual invasion. Only two of the exercises involved American units. FABIUS I was the rehearsal for Assault Force O and included primarily elements of the 1st and 29th Divisions and the Provisional Engineer Special Brigade Group, under the command of V Corps. FABIUS
VI was a marshaling exercise for certain of the build-up units in the Southern Base Section area. The primary purpose of these exercises was to give the entire invasion machinery an opportunity to function as a whole in a trial run. Every attempt was therefore made to duplicate the conditions expected in the Normandy invasion.
The over-all plan for FABIUS I was drafted by First Army headquarters, but the more detailed planning began with V Corps and continued through the various lower echelons. Approximately 25,000 troops from Force O were involved, including three regimental combat teams (from the 1st and 29th Divisions), two Ranger battalions, two tank battalions, and three engineer combat battalions with various attachments from the Provisional Engineer Special Brigade Group. Patterned after the tactical plan for OVERLORD, the exercise provided for preliminary air and naval bombardments (the former simulated), landings at H Hour by amphibian tanks and infantry at Slapton Sands, followed by engineers who were to blow underwater obstacles, open beach exits, and remove mines. Other infantry troops and Rangers were also to land, with assignments similar to those in OVERLORD, and additional engineer and service troops were to organize the beach, unload cargo, and set up supply installations.
The operation proceeded generally as planned. Marshaling was smooth, the operation of the camps encountered no outstanding difficulties, and embarkation also went successfully. With most of the craft loaded, D Day for all the FABIUS exercises was postponed 24 hours (to 3 May) by 21 Army Group because of unfavorable weather, as was later necessary in the actual launching of OVERLORD. Thereafter the assault was launched as planned. Its tactical progress is of no concern here. Four beaches were opened and given the same designations as the Normandy beaches, and battalion beach groups quickly opened beach exits and roads. Some engineer units, including the 5th and 6th Engineer Special Brigades headquarters and the Provisional Group headquarters, did not make the sea voyage but moved via motor to Slapton Sands and set up installations there. Token supplies were landed just as in exercise TIGER.
FABIUS I probably came as close to following a plan as any of the exercises held thus far. Once more, however, it disclosed flaws, some of them old defects, some new. Perhaps the most applicable of the earlier criticisms was the one concerning poor traffic regulation, which resulted mainly from the tardy arrival and inadequate numbers of properly briefed military police. There also were difficulties over maintaining proper supply unloading records, and over the proper number of DUKWs required per coaster and their loading capacity. Certain units, particularly signal troops, made the usual errors in their scheduled landing. Some attempts were made to rectify these deficiencies but the time was now short and many of the criticisms of FABIUS I were later applied to the Normandy operation.
Meanwhile FABIUS VI was held to test the organization that would call forward and marshal the early build-up forces in Southern Base Section. About 50 percent of the first three days’ build-up scheduled to move through Portland and Southampton were actually marshaled. These included mainly elements of the 2nd Armored and 9th Infantry Divisions and the 187th Field Artillery Battalion. About 35,000 men and 5,000 vehicles were called forward to the embarkation points and
then returned to their home stations without embarking. In general the machinery worked quite smoothly, but while the marshaling of assault units had been refined through the many exercises, the marshaling of the build-up forces still left some room for improvement. There was the ever-present trouble over traffic control, the coordination of which was difficult at best. It was found, for example, that the speed limit of twelve miles per hour imposed on motor convoys was too slow. Loss of command control in the marshaling camps resulted from the splitting of battalions and companies, and there was some overcrowding in the camps. Measures were taken to correct these deficiencies before OVERLORD was launched.
As the units from FABIUS VI completed their marshaling exercise and moved to their home stations, FABIUS I units returned from the assault area and reentered these camps. There they remained until called forward to embark for OVERLORD. The movement into the marshaling areas for FABIUS I in a sense therefore constituted the first step in the execution of the cross-Channel operation.
FABIUS and TIGER had little of the experimental in their make-up. They were the final rehearsals. With D Day a month away, there was little time for drastic revision of either the plan or the training of units, or for correction of errors and defects. TIGER and FABIUS climaxed a long period of study, experimentation, tests, and exercises, bringing together the lessons of past experience and the fruits of planning ingenuity. Had the men who participated in these exercises known that these were the last dry runs before the invasion they might have breathed a sigh of relief. Every training action taught new lessons. But to the participating units the exercises had already become routine and monotonous. The 1st Engineer Special Brigade, for example, had taken part in fifteen in the preceding four months. There was a tendency on the part of some personnel, therefore, to regard TIGER or FABIUS as just another in an endless series of training exercises.