BROAD OUTLINE OF OPERATION “OVERLORD” BASED ON EXTRACTS FROM THE REGIMENTAL WAR CHRONICLES OF THE OXFORDSHIRE & BUCKINGHAMSHIRE LIGHT INFANTRY VOL 4 1944-1945 1
AREA OF ASSAULT A close study was made by combined U.S. and British staffs of the German defences along the entire Atlantic coastline, as a result of which it was decided that a landing should be made in Normandy simultaneously by American, Canadian and British forces.
U.S. forces were to be on the right and British and Canadian on the left.
I CORPS I Corps was allotted to the left of the 21st Army Group front and comprised the 3rd British Division and 3rd Canadian Divisions (assault divisions) and the 51st (Highland) Division (follow up).
It was to be maintained by Nos. 101 and 102 Beach SubAreas.
TOPOGRAPHY
COASTAL AREA The section of coast allotted to the 3rd British Division was on the left of the I Corps front. For reference, the coast was divided into Peter, Queen and Roger sectors (when viewed from the sea and calculating from right to left), and each sector was subdivided into Green, White and Red beaches.
These sectors covered the following stretches of coast: Peter.—Inclusive Luc-sur-Mer to exclusive Lion-sur-Mer. Queen.—Inclusive Lion-sur-Mer to inclusive La Breche. Roger.—Exclusive La Breche to the mouth of the River Orne.
BEACHES PETER SECTOR A landing was not desirable anywhere in Petersector, as underwater rocks, named Les Roches de Lion, stretched from the beach for 500 yards out to sea and only light craft at high water could cross these rocks.
Steep limestone cliffs, twenty-five feet high, prevented easy egress from the narrow beach lying between the cliffs and the rocks.
QUEEN SECTOR Les Roches de Lion extended to Queen/Greenbeach and made it equally unsuitable, but Queen/Whiteand Redappeared to be excellent beaches with a total breadth of 1,500 yards clear of rocks.
ROGER SECTOR Roger/Green,a continuation of Queen/Red, looked equally good, but Roger /White and Red were not considered satisfactory owing to the formation of sandbanks in the delta at the mouth of the River Orne.
CONCLUSION Queen/ White and Red and Roger/Greenformed a continuous beach of 2,300 yards in breadth entirely suitable for the assault and for beach maintenance.
DEPTH OF BEACH From back of beach to low water—400 yards. From back of beach to high water—30 yards.
COASTAL BELT TO REAR OF Queen AND Roger BEACHES The beaches were backed by a line of sand-dunes, ten to twenty yards in depth, and ten to fifteen feet high, sloping seawards at an angle of 45degrees.
At the back of the sand-dunes a rough track ran parallel with the sea and numerous exits could be seen on air photographs leading from the beach across this track and thence to the main road.
Parallel with the track, 150 to 200 yards inland, ran a main road twenty feet wide, bordered by a tramway.
Between the track and the main road lay small villas set in gardens. Some of these villas were reported to have been demolished to improve the field of fire of the strong-points defending the beach.
The small towns of Lion-sur-Mer and Riva Bella marked the right and left extremities of the beach.
GENERAL DESCRIPTION OF HINTERLAND The country between the beaches and Caen, seven miles in-land, was open and undulating, dotted with small woods and villages. Large, open fields with Norman bocagestrip cultivation surrounded the villages. Roads and tracks were plentiful but narrow, generally not wider than twenty feet but of good surface.
The country immediately inland was flat, but a ridge 100 feet high, with its highest point at Periers-sur-le-Dan, dominated the beaches.
With a sub-soil of limestone the country was expected to be well drained, suitable for dumps and the passage of heavy lorries off the roads.
The country chosen for the beach maintenance area (that portion of the coastal plain which lay behind Lion and Luc) appeared satisfactory both in size and from the roads available,
RIVER ORNE AND CAEN CANAL The river and canal ran parallel to one another from the sea to Caen. Each varied in breadth between 100 and 150 feet and were separated by a strip of marshy ground.
Only one road crossed both river and canal between the sea and Caen, and this was at Benouville.
GENERAL CONCLUSION This appreciation of the country in which the 3rd Division was to land proved accurate. Excellent oblique air-photograph enlargements enabled the planners to study the country until they felt that they had known it since childhood, although in fact no one had any first-hand knowledge of the area.
GERMAN DEFENCES
PRINCIPLES OF DEFENCE The German plan for the defence of the Atlantic coastline was similar to that adopted by the British Army when threatened by invasion in 1940.
The coastal area was defended by divisions of comparatively low-grade troops, who were stationed in the concrete defences of the much-advertised Atlantic Wall, while the best troops were held in reserve in rear of the beaches. These were prepared to counter-attack any enemy who breached the coastal defences.
COMPOSITION AND PROBABLE DEPLOYMENT OF GERMAN TROOPS OPPOSED TO THE 3RD BRITISH DIVISION The coastal belt to be attacked by the 3rd British Division was defended by one division on a considerable frontage, with all three regiments on the beaches. Each regiment, however, had one battalion in reserve and a number of old tanks.
A mobile reserve consisted of a high-grade armoured division (graded by us at 90 per cent. of full German efficiency), the 21st Panzer. This was based on Lisieux at the time of planning, but was moved later, as a result of a tour by Field-Marshal Rommel, to the south of Caen.
It was estimated that British air attack would delay the concentration and movement of the 21st Panzer Division. Further, it was doubtful whether the German command would commit the division until the direction and weight of the Allied thrust were apparent. Nevertheless, it was considered that a counterattack might be delivered on the evening of D Day or early on D+1.
Thereafter there would be a race between the German and Allied armies for the full deployment of their forces.
COASTAL DEFENCES As a result of air photography and information obtained through other channels the intelligence staffs had prepared maps on which detailed particulars of the German defences had been overprinted.
The defences consisted of strong-points, 150 to 300 yards apart, commanding all points at which a landing was considered possible. The strong-points were manned by garrisons varying from a platoon to a company in strength, which were housed in strong, concrete blockhouses or field works. Houses had been demolished where necessary to improve the field of fire of the garrisons and render them mutually supporting. The strong-points were strengthened by mineflelds, belts of wire, and in some cases by anti-tank ditches.
The garrisons were armed lavishly with automatic weapons (some of which were housed in hand-traversed cupolas), and anti-tank guns were placed to cover the beaches or hinterland or both.
Many strong-points were equipped with such additional weapons as flame-throwers, rockets and Beetle tanks (small electrically driven tanks which could be directed on to the beach and exploded), and immensely strong concrete bunkers, provided with air-conditioning plant, housed the garrison.
It was known that the sand dunes would be mined and it was expected that the beach itself would also be mined, but the exact position and extent of the minefields were doubtful.
ARTILLERY A formidable artillery had been stationed in rear of the beaches and provided with concrete shelters.
It was known that twelve field and twenty medium guns could be brought to bear on Queen/ Roger sectors, and it was probable that mobile guns would be added to this number.
Fourteen inch guns mounted at Le Havre at extreme range could cover Queen/Roger anchorage and caused considerable anxiety.
BRITISH PLAN
6TH AIRBORNE DIVISION For the successful development of the British plan of attack it was essential that the left flank should be protected securely. The double water obstacle of the Caen Canal and River Orne provided an ideal anti-tank obstacle and the general assault was to be preceded during the night of D-1 /D Day by the landing of troops of the 6th Airborne Division with the object of securing the bridges over this obstacle, seizing the high ground to the east of it, and silencing a battery of heavy guns near Franceville Plage.
R.A.F. This airborne landing was to be followed at first light by a general bombardment of the coastal area by heavy bombers of the R.A.F., when 2,400 tons of bombs were to be dropped on the 21st Army Group front, the attack to be shifted inland on to centres of communication as the Royal Navy approached the coast.
Thereafter a patrol of five squadrons of fighters was to be maintained over the bridgehead during the hours of daylight.
Ten thousand aircraft were to be available for these operations.
ROYAL NAVY Minesweepers on the left of the assault had to sweep two channels (numbered 9 and 10) through the enemy mineflelds. One channel was to lead to Queen/Roger sector for the assault, the other in the form of a J was to be farther to the east for the bombardment squadron.
The convoy of vessels carrying the assaulting troops and the bombardment squadron was ordered to assemble south of the Isle of Wight on the night of D-1 /D Day.
The bombardment squadron was to consist of: H.M.Ss. Rodney and Warspite, battleships. H.M.S. Roberts,18-inch monitor. Six cruisers. Twelve destroyers and rocket craft.
The naval bombardment of the enemy defences was planned to begin at H-45minutes and continue until H hour, when the destroyers had orders to close with the beach defences. If hit and in danger of sinking, they were instructed to beach and engage the shore guns at point-blank range.
At H hour destroyers were to move to the left flank, protect the heavy ships and hold off any enemy naval counter-attack.
The heavy ships were to continue the bombardment and to provide any fire requested by the land forces in direct support.
3RD BRITISH DIVISION The assault was to be led by dual-drive tanks of the 27th Armoured Brigade, which would deal with any guns not silenced by the R.A.F. and Royal Navy’s bombardments.
Five minutes later A.Vs.R.E. (armoured vehicles, Royal Engineers) were to land and blast a way through any wall or obstruction preventing egress from the beach. Assault engineers were also to start demolishing the beach obstacles.
The first wave of assaulting nfantry of the 8th Infantry Brigade was to touch down five minutes later. This brigade was given the task of mopping-up the beach garrisons and securing the high ground at Periers-sur-le-Dan.
The 185th Infantry Brigade was then to land, assemble near Hermanville, pass through the 8th Infantry Brigade, and capture Caen.
The 9th Infantry Brigade was to assemble to the rear of the beaches and be prepared either to assist the 3rd Canadian Division landing on the right of the 3rd British Division or to support the 185th Infantry Brigade should it have failed to capture Caen.
The division was then to consolidate on the high ground to the south of Caen and be ready for the expected attack by the 21st Panzer Division.
COMMANDOS In the meantime the 4th Commando was to mop up Quistreham and secure the locks at the mouth of the Caen Canal.
The 41 Royal Marine Commando was detailed to capture Lion-sur-Mer and Luc-sur-Mer, while the 44 Commando, which had landed with the Canadians, moved east and joined them. Both were then to silence any resistance in Douvres-LaDelivrande.
No. 101 BEACH SUB-AREA Plan A.— the decision to attack on a one brigade front necessitated a complete change in the standard deployment drill of No. 101 Beach Sub-Area. Although it might have been possible to divide the beach at La Breche into two and land No. 5 Beach Group on one beach and No. 6 Beach Group on the other, it was considered better to land No. 5 Beach Group with the assaulting brigade on first tide with the object of developing the beaches and establishing sector stores dumps.
No. 6 Beach Group was then to land on second tide and establish the beach maintenance area, or carry out thealternative plans described later.
The beach companies of No. 6 Beach Group were to be placed under command of No. 5 Beach Group on landing and to enlarge the beach.
The dump units of No. 5 Beach Group were to assist No. 6 Beach Group in working the beach maintenance area and to be under command of No.6 Beach Group.
All sapper transportation troops. R.E. and R.A.S.C. transport facilities were to be pooled and retained under direct command of No. 101 Beach Sub-Area.
Thus when fully deployed: (a) No.5 Beach Group would work the beaches. (b) No.6 Beach Group would work the beach maintenance area. (c) No.101 Beach Sub-Area would be responsible for transportation. R.E. and transport.
LANDING OF No. 6BEACH GROUP
General .—Themain body of No. 6Beach Group was planned to land second tide, but an advanced party was to be landed first tide and parties not essential to the early development of the maintenance area were relegated to third or fourth tides and to subsequent days.
Surplus transport was placed under command of Captain E. A. Low (1st Bucks) and was scheduled to land D+17 onwards.
Advanced Party.—Anadvanced party, consisting of representatives of the services and provost, was to land first tide under the command of Major Boehm (1Bucks), with the task of carrying out a reconnaissance of the beach maintenance area as soon as it was possible to do so. Major Boehm was to report to the beach group commander, who would land with the main body, thus enabling the latter to make any corrections in the first key plan before the deployment of the main body.
The 1st Bucks anti-tank platoon was to land also on first tide and deploy immediately.
Main Body.--On landing second tide at H+11 hrs the main body was ordered to form in transit areas and await further orders for deployment until the commanding officer had heard Major Boehm’s report.
Troops to be employed on the beach were exempted from this order and were to begin work immediately on orders of the commander of No. 5 Beach Group.
COMPOSITION OF No. 6 BEACH GROUP
1st Buckinghamshire Battalion 37 officers 810 men Military Landing Officer’s party 2 officers 8 men 91st Field Company, R.E 7 officers 213 men Detachment, No. 50 Mechanical Equipment Platoon, R.E 1 officer 30 men 1028th Port Operating Company, R.E 7 officers 333 men 238 Petrol Depot 2 officers 24 men 299 General Transport Company, R.A.S.C 7 officers 248 men 138 Detail Issue Depot, R.A.S.C 3 officers 33 men 9th Field Dressing Station, R.A.M.C. 6 officers 91 men 12th Field Dressing Station, R.A.M.C. 6 officers 91 men 37th Field Surgical Unit, R.A.M.C. 2 officers 9 men 38th Field Surgical Unit, R.A.M.C. 2 officers 9 men Detachment, 2nd Field Hygiene Section, R.A.M.C. 0 officers 2 men No. 12 Ordnance Beach Detachment, R.A.O.C. 5 officers 65 men 245th H.Q. Provost Company, C.M.P. 3 officers 80 men No. 21 Beach Recovery Section, R.E.M.E. 1 officer 28 men No. 85 Company, Pioneer Corps 6 officers 285 men No. 149 Company, Pioneer Corps 6 officers 285 men No. 102 R.A.F.Beach Section 5 officers 36 men No. 18 Beach Signal Section 2 officers 28 men R Commando, R.N 11 officers 73 men 121 officers 2781 men
The following came under command at a later stage and so remained for the operation: No.9 Stores Section, R.E No.22 Field Transfusion Unit, R.A.M.C. No. 51 Beach Balloon Unit. Role allotted to 1st Bucks Battalion Headquarters.—Command of No. 6 Beach Group.
A and B Companies.—Beach companies opening new beaches on landing.
C Company.—In support of ammunition-ordnance dumps.
D Company.—Reserve company.
S Company: Anti-Tank Platoon.—Anti-tank defence of area. Mortar Platoon.—Organisation of unaccompanied G1098 stores dump. Carrier Platoon.—In support of supplies dump.
H Company: Signal Platoon.—Beach signals. Pioneer Platoon.—Mine clearance and construction of Headquarters, No.6 Beach Group.
MAINTENANCE PLAN
Basis of Calculation.--Three hundred and fifty tons of stores per day were considered sufficient to maintain one division in the Mediterranean, but for Operation “Overlord” this figure had been increased to 750 tons per day.
D Day.—Two landing craft, tank, each carrying 200 tons of stores (mostly ammunition), were planned to beach at H+2, and a further two at H+4.
The total of 800 tons was to be used to stock four sector stores dumps.
A further 1,783 tons of mixed stores was to be carried by: (a) Preloaded second-line transport, general transport vehicles and Dukws. (b) Nine landing barges, vehicle, and four tactically loaded coasters arriving at H+10.
These and subsequent deliveries were to be consigned direct to the beach maintenance area, which was to be ready to begin issues of ammunition and certain ordnance stores from 2359 hrs on D Day and of all other stores from 0900 hrs on D+1.
In addition to these quantities, it was decided very shortly before D Day to attach a hundred l0-cwt. trailers to certain vehicles landing on the first four tides. These trailers, containing ammunition, were to be cast loose on landing and moved by beach troops to the ammunition dump as opportunity offered.
D+1 to D+7.—The maintenance plan provided for a total of 23,732 tons of stores being landed during the first eight days of the operation on sector Sword.
The whole of the British landing beaches were divided into three sectors, named from east to west Sword, Juno and Gold. The naval forces were correspondingly known as Force S, Force J and Force G.
“Gooseberry.”--The Royal Navy were to sink a line of ships one mile off the beach on D+1 to act as a breakwater. This was to be known as a “gooseberry.”
Behind this breakwater ships were to unload: Stores to: (i) Dukws delivering direct to dump; or (ii) Craft which would tranship to lorry, thence to dump. Vehicles from: (i) Beached landing ships, tank; or (ii) Motor transport ship to Rhino ferry or craft, thence to shore. Men from: (i) Ramps of landing craft, infantry; or (ii) By craft to shore.
Loading of Coasters.--Coastersreporting on D Day were to be loaded tactically—that is to say, with a mixed cargo—so that the loss of a coaster would not lead to the total loss of a commodity.
From D+1 to D+5 coasters were to be loaded with two or three commodities.
Thereafter coasters were loaded with one commodity only.
Vehicles.—The following number of vehicles were to be landed on the first four tides: D Day Tide 1 1,510 vehicles D Day Tide 2 720 vehicles D+l Tide 3 532 vehicles D+l Tide 4 118 Total= 2,880
Rate of Discharge.—Itwas planned to land 2,200 troops and 1,500 vehicles in the first nine hours.
DEFENCE Ground.—Headquarters, No. 6 Beach Group, and each dump were to be organised as a defended locality.
Defence of the beaches was to be organised by each beach company commander.
Co-ordination of the defence of the whole area was to be the responsibility of the second-in-command of No. 6 Beach Group.
Anti-tank.--Atank stop line was planned on the second lateral. The twelve 6-pounder anti tank guns of the 5th King’s and the 1st Bucks were to be landed first tide and all anti-aircraft guns were to be sited in an alternative anti-tank role. Piat mortars were to be sited and dug in. Mineflelds were to be laid as required.
An immense quantity of anti-tank artillery was to be landed with the brigade and hurried inland, and the beach sub-area stop line was to be the final barrier to a penetration to the beaches.
Smoke.--A smoke line was to be established by the pioneer smoke company on the line of the second lateral and was to be ready to operate by the afternoon of D Day. Balloons.--A barrage of sixty balloons was to cover No. 101 Beach Sub-Area.
MINE CLEARANCE Royal Engineers were given a priority for clearance of land mines and Flails (tanks) were allotted for clearance of beach mines.
All men were to be capable of clearing mines and a liberal supply of mine detectors was issued.
ALTERNATIVE PLANS Mention has been made of the 14-inch enemy guns at Le Havre. Plans existed to silence these, but should they fail the Royal Navy was not prepared to use the anchorage off La Breche.
In that event alternative plans were as follows:
Plan B.--No.6 Beach Group, with nine landing barges, vehicle, and four coasters to be switched to Langrune, to work a beach on the 3rd Canadian Division sector (Juno)and form a beach maintenance area south of Langrune.
The whole of this area was reckoned to be out of range of the batteries at Le Havre.
Plan C.--Alternatively, Plan C provided for unloading at Langrune and ferrying stores overland to beach maintenance area as in Plan A.
1. The Oxfordshire & Buckinghamshire Light Infantry Chronicle, Vol 4: June 1944 - December 1945 Pages 105-117