Operation Neptune
Page 13
It was appreciated by the planning staff that the recovery of damaged craft from the far shore would not be solely a matter for tugs. There would almost inevitably be cases of coasters stranded on the beaches and unable to haul themselves off with their kedge anchors. Nor could tugs help efficiently in the case of assault and landing craft which might become “broached to” on the beaches. Yet the recovery of these vessels would be important, not only so that they could be put back into service, but also to clear the beaches. For this reason beach salvage parties were organised and trained. They were provided with tractors to serve as “land tugs” and bulldozers to help in pushing stranded craft back into the water.
The task of recovery and repair on the far shore was likely to be great, and for this reason strong beach repair parties were organised, and HMS Adventure, a minelaying cruiser, and HMS Albatross, a seaplane carrier, were fitted as special repair ships to work off the beaches.
Both the repair and the tug organisations had, of course, to work in the closest co-operation with the salvage organisation which was specially set up for the invasion. To run this organisation Admiral Sir Bertram Ramsay secured the services of the greatest salvage expert in the United Kingdom. This was Mr T. McKenzie, of Metal Industries, Ltd., who had handled the salvage in Scapa Flow of the scuttled ships of the German High Seas Fleet of the last war. Mr McKenzie joined the staff of the Allied Naval Commander-in-Chief on 15 January 1944, being gazetted a Commodore RNVR. The salvage organisation was also charged with the responsibility for wreck disposal. It was recognised that the wrecks of sunken vessels might obstruct the approaches to the beaches more effectively than enemy action during the critical “follow-up” and initial “build-up” periods, and that this was a danger which might well be exploited by the enemy.
From the beginning Commodore McKenzie’s organisation was limited by shortage of heavy salvage gear, and above all by shortage of tugs. The latter caused Admiral Sir Bertram Ramsay no little anxiety. The towing commitments began some time before D-day owing to the need to assemble the components of the “Mulberry” harbours and the blockships for the “Gooseberry” shelter harbours, as well as all manner of dumb lighters and barges. He was aware that a great strain was unavoidably being placed upon the whole tug organisation, and particularly upon the crews of the tugs. At one stage prior to D-day representations were made to him that the available tugs were being greatly overworked. He replied: “Everyone must be prepared to work harder than they have ever had to work before. It cannot be helped. It has just got to be put up with.”
One of the greatest technical achievements which was called for during the preparatory period was the waterproofing of many thousands of vehicles of great variety of type. This entailed experiment, manufacture of the special fittings required in order to “waterproof” the vehicles, and trial of the vehicles so fitted.
This waterproofing was no mere matter of making the mechanical and electrical mechanisms of the vehicles “splash-tight.” They had to be really waterproof, for it was recognised that wave conditions might make it inevitable that vehicles would be almost totally submerged before they drove up the beach. The waterproofing of all these vehicles was not a naval commitment, except in so far as the navy was greatly interested and concerned in the experiments and trials, but it is worth recording the fact that for some months almost the entire tin-plate industry of the United Kingdom was engaged on the manufacture of the special shields and fittings required.
Meanwhile a great deal of surveying work was being done by the Royal Navy off the French coast. It must be remembered that such charts of the French coast as were in our possession were based upon surveys at least four years old. Shoals have a way of shifting, particularly in places where there is a large rise and fall of the tide. “Neptune” was an operation in which inches in the depth of water would be important. Nor was this all. A geological survey was also necessary to determine the nature of the beach and the sea bed below low-water mark. The components of the “Mulberry” and “Gooseberry” harbours had to be sunk in the correct depth of water, and it was also important to know the nature of the bottom in these positions. A “Phoenix” or a blockship would sink gradually down in soft mud, but would remain at a given level if settled on gravel or firm sand. Heavy vehicles, too, might get “bogged down” before reaching high-water mark if the beach was too soft.
To discover all these things surveys of the French coast were undertaken months before D-day. The very design of the “Mulberries” depended to a great extent on the results of the preliminary surveys.
It is no easy matter to survey the beaches and the sea bed close off a coast strongly defended and held by a determined enemy. It is even harder to do so and keep the enemy in ignorance of one’s intentions. Surveying is an art which demands concentration and great accuracy if the results are not to be a menace. It is difficult enough by day in peace-time. Yet it was achieved on dark nights close under the guns of enemy shore batteries by some of the coolest heads that have ever worn naval caps.
Most of the work was done by RNVR officers in specially converted LCP’s (Landing Craft, Personnel). The personnel space in these little craft was decked in and became a fairly large chart room and they were fitted with accurate compasses and echo-sounding machines. In their new guise they were called LCP (Sy)—the (Sy) indicating that they were specially fitted for surveying.
On every night during the dark periods of the moon when the weather was at all feasible these little craft worked close off Hitler’s “Atlantic Wall,” while others actually landed parties in dinghies to scoop up samples of the beaches from which the scientists could tell how they would stand up to the beaching of vessels and the passage of heavy traffic. In order to avoid giving the enemy any clue of the places in which we proposed to effect the main landing of the invasion, these surveys were carried out along most of the possible stretches of the French north coast, and one surveying party which was landed in the Pas de Calais area failed to return.
On the whole, however, the Germans paid practically no attention to these surveying activities. The reason for the immunity of the surveyors from enemy interference was the subject of considerable conjecture. It seemed impossible to believe that the German look-outs were so blind or their radar organisation so inefficient that they remained unaware of the presence of the surveying craft close off their coasts. Some would have it that the Germans had orders not to open fire since to do so would reveal the position of their batteries and strong points; others that the Germans were years behind us in the use of radar and employed it only for the control and ranging of their gunnery and not as a warning system.
Whatever the reason we may be thankful that our surveyors did not suffer heavy casualties.
The planning staffs had in the meantime pressed on with the planning of the details of the operation and with the preparation of the Operation Orders. As has been said, these Operation Orders for “Neptune” comprised a printed book of foolscap size nearly three inches thick. They were the most detailed operation orders ever issued. They left nothing to chance and covered every possible contingency. In the “build-up” section detailed orders were laid down for the sailing of the first 47 convoys after the initial assault. These 47 convoys were to sail to France by D plus 3, after which the three-day convoy sailing schedule would be repeated over and over again. In the operation orders there were included what were called “Mickey Mouse Diagrams.” These were charts on which the positions of every convoy and every minesweeping, covering or bombarding force were plotted at a given time. There was one such “Mickey Mouse Diagram” for every hour during the approach phase, and by turning them over quickly one got the effect of a motion picture showing the movement of all the hundreds of groups of ships taking part.
The operation orders also detailed the actual beaches to be used in the Bay of the Seine area. There were to be five such beaches and assault areas off the beaches, and they were all given code names for rapid identification purpos
es.
To the west of the little harbour of Port en Bessin there were two beaches over which the United States troops were to land. These were called OMAHA and UTAH beaches. East of Port en Bessin there were three beaches, which were to be used by the British and Canadian troops. These from west to east, were called GOLD, JUNO and SWORD.
Thus there were five main beaches to be used in the initial assault. Each beach was to be assaulted by a division of troops, thus fulfilling General Montgomery’s requirement of assault on a five-divisional front. Each division of troops to be landed in the initial assault was to be transported across the Channel and landed by a separate naval assault force, which was known by the initial letter of the beach to be used. Thus “Force G” was charged with the landing on GOLD beach and “Force S” with that on SWORD. In addition to the five assault forces there were two “follow-up” forces, each carrying one division of troops for the immediate follow-up of the assault. The British “follow-up” force was called “Force L” and the American “follow-up” force was called “Force B.”
The chain of naval command therefore became:
The operation orders for “Neptune” were ready for issue on 24 April 1944. That is not to say that they were by any means final. Again and again they had to be corrected or amended as new problems arose and their solutions were formed. This went on until shortly before D-day, when the operation orders were “frozen” by signal from the Allied Naval Commander-in-Chief. This step was necessary in order to ensure that no amendment would be issued so late as to be received by some of the forces taking part and not by others which might have already put to sea.
In so vast an undertaking as the preparation for the invasion of Normandy it was inevitable that a great many people should be “in the know,” and that the number of these should increase rapidly as the plans and preparations advanced. Naturally, all possible steps were taken to ensure that nobody knew more than was essential to his job, but there is often much truth in Benjamin Franklin’s dictum that “three may keep a secret if two of them are dead.”
Secrecy—or “security,” to use the Service term—was vital to the success of the invasion, and the fact that the place, time and strength of the invasion were kept so secret that tactical surprise was achieved in the assault must be considered a great triumph for the Security Executive, the Inter-Services Security Board, and all who served under them.
Men have for long cherished a belief that women can never keep a secret, yet many thousands of “Wrens” were engaged in the work of preparation for “Neptune,” and they proved themselves at least as “secure” as naval officers of considerable experience and training. The naval commander of one of the assault forces wrote in his report: “Nor must the work of the WRNS officers and ratings be forgotten. In spite of working very long hours, they remained keen and cheerful, and I knew of no instance of even the smallest lapse of security in spite of the fact that the majority of them had access to all TOP SECRET papers from the beginning.” It must be remembered that most of the cypher staffs dealing with ‘most secret’ signals, as well as the typists, teleprinter operators, and others were “Wrens.”
The requirements of security for operation “Neptune” raised all manner of problems, many of which had never before been contemplated, and some of which demanded action which is normally repugnant to free and democratic peoples. There was, for instance, the necessity to “seal” ships and even camps and shore establishments so that there should be no communication between their inmates and the outer world. There was the need to empound all mails belonging to any of the forces to be engaged—a step which had to be taken about ten days before D-day. There was also the problem of the sick and the wounded. If a man from a “sealed” ship, who had been “briefed” and therefore knew the all-important secrets of when and where the invasion was to take place, was sent to hospital through sickness or injury; was the hospital, or the ward to be regarded as “sealed”? If a man was on the danger list, was access to his bedside to be denied to his relatives? Here was a direct conflict between the unfeeling ideals of security and the principles of common humanity. The Admiralty abided by the latter and directed that relatives should not be denied access to men seriously ill or injured, but the most elaborate precautions were taken to guard against any leakage of secret information.
At the same time it was desirable to mislead the enemy whenever possible regarding our intentions. In this various factors came into play. There was, for instance, the temporary sinking of the “Mulberry” harbour sections off Dungeness, opposite Boulogne; and the great concentration of British bombing in the Pas de Calais area prior to D-day.
Another important factor was the great, and quite fortuitous, concentration of shipping in the northern and north-eastern parts of Great Britain prior to D-day. This was inevitable, because all the southern ports from Harwich round the south coast to Milford Haven were so full of “invasion” shipping that all the ordinary shipping was forced to use the more northerly ports and caused an unusual accumulation of shipping in those ports. This concentration of shipping was known to the enemy, and added considerably to the German High Command’s anxiety about a possible invasion of Norway. This was an anxiety which the Germans had felt for some time. It was still further increased by actions taken by the Allies shortly before D-day.
One of these was part of our pre-D-day mining campaign, which included an intensification of our mining of the Southern Baltic, the mining of the Sound, between Denmark and Sweden, and of the Kiel Canal. All these were, in fact, carried out for the greater protection of our projected invasion of Normandy, but they appeared to the German High Command to be an attempt to sever the German sea communications with Norway. We now know that the mining of the Kiel Canal was highly successful and forced the German High Command to take emergency measures for the regrouping of their slender shipping resources. At the same time there was considerable British minelaying activity on both sides of the Pas de Calais area, which might well have indicated that the Calais-Boulogne area was our objective.
Another Allied action which seemed to the German High Command to indicate that we were contemplating a descent upon Norway was the series of concentrated air attacks on U-boats off the Norwegian coast shortly before D-day. These attacks, which were highly successful, were in fact designed to prevent as far as possible, the U-boat squadrons in Brest and the Biscay ports being reinforced from Norway just before D-day, but they certainly helped to focus German attention on Norway.
All these factors helped to make the German High Command “take its eye off the ball” at the critical moment. The enemy was expecting feints before the invasion proper was launched, but the indications which reached him pointed either to Norway or the Pas de Calais area as the probable scenes of the main efforts of the Allies. Although he was very nervous about Norway, he believed it more likely, on the whole, that we would launch the main attack in the Pas de Calais area. This was partly due to the fact that he over-estimated our desire to assault the area from which the flying bombs were launched against London and southern England.
There were moments of anxiety regarding the security of the actual invasion plans, but the event was to show that this had been very good indeed, while the German High Command was “kept guessing” even after D-day and was reluctant to move reinforcements to Normandy during the first few days of the invasion.
CHAPTER VII
DECISION AND ANXIETY
Assembly of the forces—Obstacles dictate daylight assault—Final exercises— Preliminary actions—The British mining campaign—The minesweeping problem caused by the change of tide—Anxiety about the weather.
On 26 April 1944, the Allied Naval Commander-in-Chief and his staff moved from London to his battle headquarters. This was at Southwick Park, outside Portsmouth. It was a house which had already been taken over by the Admiralty to house the Navigation School—known as HMS Dryad—when that establishment had been forced to move out of its old quarters in Portsmouth D
ockyard owing to the blitz.
On the same day the assault forces assembled at their ports of departure as follows:
Force S at Portsmouth.
Force G at Southampton.
Force J in the Isle of Wight area.
Force O at Portsmouth.
Force U at Plymouth.
Follow up Force L at the Nore.
Follow up Force B at Milford Haven.
The stage was set for “Operation Neptune.” Yet, astonishing as it may seem, neither D-day nor H-hour had then been definitely decided. It had not even been finally decided whether the initial assault should take place in daylight or during the dark hours or at what state of the tide the first wave should “touch down” on the Normandy beaches. The two decisions were, of course, interdependent.
During the initial stages of the planning of the invasion of Normandy Admiral Sir Bertram Ramsay had been in favour of the initial landing taking place in darkness, shortly before dawn. This preference he had formed as a result of experience in the highly successful invasion of Sicily, which he had planned and during which he had commanded the British Task Force.
As the planning progressed, however, Admiral Ramsay changed his view, for he realised that the advantages of an assault in darkness would, in the case of the invasion of Normandy, be outweighed by our unquestionable naval and air superiority, with ships and aircraft working from great bases in close proximity to the assault area. There was also another consideration: the vast number of ships and craft of all types to be deployed made it advisable that the assault should take place in daylight.
Having formed this considered opinion, the Naval Commander-in-Chief never wavered from his view that the initial assault should take place by daylight, but as early as possible in the day in order to give the maximum opportunity to our air forces and our naval bombardment forces. The military authorities, however, urged more than once that the plan should be altered to provide for the initial assault taking place in darkness. Moreover, the army wished to be landed dryshod at high water, which would, of course, have meant the stranding of many craft for six hours or more.