by J E Kaufmann
Some of the defensive works built in Great Britain during World War I included a number of pillboxes that remained in place. The old coastal defense positions, dating from the latter part of the nineteenth century and modernized somewhat at the beginning of the twentieth, had received few improvements since then. When rearmament began in 1934, the navy gave some consideration to the coast defenses. Since the main concern was air defense, the Reorientation Committee decided in 1935 to orient the air defense zone toward the east and Germany rather than France. The Aircraft Fighting Zone ran from the River Tees (south of Newcastle), to a point west of Harwich, Dover, east of London, and Portsmouth. Air defense served as Great Britain's first line of defense. In 1935 radar became the main asset of the warning system. By 1936, the first line of twenty stations was set up between the River Tyne and Southampton. A second group of radar stations for detecting low flying aircraft was set up later.
Until the creation of the RAF, the Royal Navy had been the main deterrent against invasion. After the advent of the airplane, the navy took on a secondary role, at least in the areas within the range of enemy air cover. The Royal Navy's mission was to prevent any successful landings. After the war broke out, most of the capital ships of the Home Fleet moved to northern ports such as Rosyth and Scapa Flow to avoid constant Axis air attacks.
Late in 1939, after examining the situation, General Kirke, the commander of the Home Forces, designated the area between the Wash and Sussex as the most vulnerable to invasion. He ordered, therefore, the improvement of the defenses of key ports and airfields as part of the Julius Caesar plan, which remained in effect until about the time of the German campaign in the west in 1940.
The German airborne operations in Norway and then the Low Countries in the spring of 1940 greatly concerned the British. From Scotland to British Somaliland, British troops were soon alerted against parachute and glider troop assaults. As a result, a considerable amount of effort was wasted on the creation of obstacles throughout the British countryside, along roads, and around bridges to prevent any type of airborne operation. Many roads were so effectively blocked, that they hindered the movement of British troops.
The Emergency Battery Program, which went into effect to protect the coast line, involved the installation of about 600 pieces of artillery, mostly in open concrete emplacements. The most important of these positions consisted of four gun batteries of 6-inch guns.
Since the coastal gun positions, built during the pre-war era and early in the war lacked overhead cover, the army had to create casemate-like positions with walls about 1 meter thick to protect them. As the Germans began to install heavy artillery in the Calais area, the British responded with a pair of old 14-inch naval guns and two 15-inch coast-defense guns. However, the largest coast defense weapons consisted of 9.2-inch guns. During the summer of 1940, Falmouth, Plymouth, Portland, Portsmouth, Newhaven, and Dover were strengthened, becoming the strong points of the south coast. Over forty battery positions were set up between these ports.
In May 1940, General Edmund Ironside, who had just become the commander of the Home Army, decided to commit his forces to a static defense since his army lacked the ability to undertake a mobile defense. He created many positions along the coast and inland to the Stop Lines that included pillboxes, anti-tank barriers, and wire obstacles.
The work continued as General Alan Brooke replaced Ironside in late June 1940. However, Brooke did not believe that the army had sufficient strength to defend such an extensive position, especially after its material losses at Dunkirk. He went back, therefore, to an emphasis on a mobile defense, concentrating his troops near the GHQ Line but moved his limited number of anti-tank guns up to the coast.
The British defensive situation was precarious, at best, in the summer of 1940. Many of the bunkers were built and located somewhat haphazardly. Many of the coastal bunkers fired only forwards rather than to the flank, others, which stood in towns or roadblocks, had no embrasures covering routes of approach. Some of the coastal bunkers built on unstable terrain collapsed into the sea. Sea walls were reinforced with sand bags, becoming defensive positions, and wire was strung all along the beaches. As the situation improved, more concrete barriers known as pimples the British version of dragon's teeth-began to cover large stretches of the coast. Meanwhile, Brooke ordered the removal of many of the obstacles blocking the inland villages so the army could move around unhindered.
New and more inventive devices such as scaffolding placed below the high water mark to hinder landing craft came into use. They also set up makeshift flame weapons. As the British situation improved and the German offensive opened in the East in 1941, the likelihood of an invasion evaporated.
By the end of 1940, the last of over 150 emergency coastal batteries were completed. By June 1942, the last large artillery batteries near Dover were also finished.
One of the most prominent features of the British coastal and air defenses was the creation of the Sea Forts. They had been planned in 1941, but not built until the following year. They occupied positions in the Thames Estuary and when completed they were used in an air defense role to replace flak ships and to give early radar warning.
2. Gibraltar
In 1932, the governor of Gibraltar received instructions to build an airfield in the northern end of the peninsula. Plans for placing the airfield across the race course were drawn up and approved. It was begun in September 1934 and was ready to serve as an emergency landing field by March 1936. In October 1941, the decision was made to extend the runway over 1,600 meters into the sea. Much of the material used to extend the airfield came from tunneling into the Rock. By January 1942, about 1,000 meters were completed, and by 1943 the entire runway was finished and ready for the Allied invasion of North Africa.'
When the war broke out, the commander of the fortress had to prepare against an attack across the Spanish border and protect the harbor facilities at the same time. Between the beginning of the war and mid-1940, the defenses of Gibraltar were considerably strengthened with much of the work carried out by laborers from Spain. Everything from construction of new tunnels to setting up new batteries was done, but many new galleries and interior positions were added during the war.
3. Malta
Little could be done to improve the defenses of Malta after Italy entered the war. Coastal defenses were set up and old battery positions improved. Most of the defenses were concentrated on the southeast coast. Five airfields were used as the first line of defense and as bases for attacks on enemy shipping and naval units.
DESCRIPTION
1. Coast Defenses
The Fortifications and Works Directorate, a branch of the War Office, decided to concentrate its efforts on only a few of the numerous designs from the World War I era. The most common position on the coast was the pillbox, one of the best known of which was the six sided one.
Most of these bunkers were designed for light machine guns, but some took anti-tank guns ranging from 2-pd to 6-pd guns. Some of every type were placed on the coast, inland behind the beaches, or on the Stop Lines.
A variety of obstacles were placed on the beaches and inland. Anti-tank obstacles consisted of concrete cubes and cylinders, the more familiar concrete "pimples" (dragon's teeth), and iron rails. These barriers blocked beach exits, and, in some cases, lined possible landing areas. In 1941, more effective standards were established, such as the installation of obstacles in several lines and the placement of cubes at an angle. Old junk cars and similar obstructions had long since been removed and replaced by the new, more standard types.
Wire was strung along the beaches to deter infantry. A line of scaffolding was erected along the coast. Explosives, which were to be detonated by approaching craft, were attached to the scaffolding below the water line. The scaffolding was made of steel tubes, was about 3 meters high, and was deployed more quickly than other types of obstacles. More scaffolding was added higher up on the beaches. Since it was never put to the test, it is imp
ossible to tell how it would have stood up but it seems that heavy bombardment would have easily disposed of it.
A typical well-defended beach included a line of concrete cubes interwoven with rolls of barbed wire along the high-tide line. A line of tubular scaffolding paralleled the concrete cubes about 10 to 15 meters to the front. Concrete pillboxes and anti-tank mine fields occupied key points along the beach such as the exits.4
In some places, a crude flame weapon may have been employed. The possibility of setting the sea afire was not considered a serious threat. Pipes carrying a flammable substance to a constricted point where it could puddle and be ignited were placed around possible landing sites. A type of fougasse weapon with a flammable substance akin to napalm was placed at a higher point where it could be ignited and hurled down onto narrow passages.
One of the first heavy artillery positions on the coast consisted of the two 14inch naval guns installed at St.Margaret's-at-Cliffe, near Dover, in the late summer of 1940. They were manned by Royal Marines and named "Winnie" and "Pooh." Both were on barbette mountings, but only Winnie received an armored gun house.' In 1940, several old 9.2-inch railway guns and a huge 18-inch railway howitzer known as the "Boche Buster" were brought into the Dover area. "Boche Buster" did not have the range to fire across the Channel. Three new fixed batteries, which included a battery of three 6-inch guns overlooking Fan Bay, the Wanstone Battery, to the north, named after the nearby farm were installed in the area later. The Wanstone Battery consisting of two 15-inch Mk 1 ("Jane" and "Clem") with gun houses, originally destined for Singapore, was completed in September 1942. Just to the east of the Wanstone Battery and south of St. Margaret's-at-Cliffe, was a battery of four 9.2-inch Mk 15 guns, also ready in 1942.
The Royal Marines served three 13.5-inch Mk 5 railway guns from late 1940 until 1942, which operated in the Dover to Deal area.6 The army added its own weapons to the defenses of Dover which included the Capel and Hougham batteries just west of Dover armed with naval 8-inch coast guns. These went into operation in 1942.
The Sea Forts, known as the Maunsell Forts after the civilian designer, were of two types: army and navy. The navy built both types. Their main purpose was to act as anti-aircraft units for stopping German mine laying aircraft and breaking up German bombing formations heading towards London. These forts also had the mission of deterring E-boat raids. The army fort consisted of several box like towers of steel comprising two levels and a roof on which their equipment was located. The tower was mounted on four concrete legs that rested on a concrete base. The lower level had the officers quarters, stores and latrine facilities. The upper level was the main barracks area for the troops. The fort's equipment and weapons were on the open deck space above this. Seven of these structures were placed close together and linked by steel bridges. The central tower was the control tower and four of the outer positions mounted the 3.7-inch guns, with one other position mounting Bofors guns. The towers with weapons formed a circle around the control position. One tower beyond these, and also linked by a bridge to one of the gun positions, served a searchlight. The entire garrison for this type fort was about 120 men.
The navy fort was mounted on two large concrete pillars which were hollow and placed on a barge shaped concrete cassion which rested on the sea floor. These pillars contained seven levels with the magazines and storage rooms on the two lower levels, and the crew area was on the next four levels. The top level of both pillars held the power generators. Above each of these pillars was a 3.7-inch antiaircraft gun on the main deck, and above them was a deck with two Bofors guns. Between the guns of the main deck were the officers quarters, a kitchen, and the latrines for the garrison. Above this was the control room and radar installation.
Three army forts were set up near the entrance to the Thames, and four naval forts stood further out in the Thames Estuary to form a radar line. Three army forts also occupied positions off the Mersey Estuary leading to Liverpool on the west coast. The Humber Estuary was protected by Bull Sand Fort (1919) and Haile Sand Fort (1918) built on sand spits. Bull Sand, armed with four 6-inch Mark VII guns, returned to full service in 1939 with two of its guns replaced by twin 6-pd weapons for anti-boat service. The military removed Haile Sand's old armament of two 4inch guns in 1928, and in 1939 set up two 12-pd guns which in 1940 were replaced with twin 6-pd guns. Older Victorian forts received new armament for similar purposes on other inlets and British harbors.
2. The Stop Lines
The Stop Lines employed defenses similar to those of the beaches, except for scaffolding. They served as anti-tank barriers. The GHQ Line depended heavily on canals and natural features. It was a continuous line, but again the pillbox remained the main defensive position. The northern sections of the GHQ Line were not completed. The three major sections found in the Southern Command's area of the GHQ Line as identified by Henry Wills in his book Pillboxes were as follows:
In addition, the numerous other Stop Lines between it and the coast included additional positions and anti-tank obstacles.
The steel rail obstacles included a type which formed a right angle. Some of the anti-tank ditches were concrete. In some cases the army built bridges to cross the anti-tank ditches so normal traffic could continue.
Over 200 pillboxes for 2-pd anti-tank guns and over 100 for 6-pd Hotchkiss guns were planned but many were not built. Many pillboxes were only bullet proof, and a number of bunkers were prefabricated. Some of the more unusual ones included cantilever roofs so as to give all round fields of fire. A retracting pillbox for five men was designed for airfields so as not to obstruct air operations. These were basically the main defenses of the island plus a few other unusual pillboxes that included one or two stories. In addition to these, almost 200 Alan-Williams steel turrets were ordered. These were steel domes which could mount a Bren or Lewis machine gun, or an anti-tank rifle.
With respect to camouflage, the British were quite resourceful. Some pillboxes were camouflaged to appear as kiosks on beaches, buildings in towns, and even signs and haystacks.
3. Gibraltar
The northern face of the rock had galleries cut into it by engineers in the eighteenth century and was improved to take modern weapons. The new chambers were cut wide enough to place Nissen huts in them or a more standard type of hut. Accommodations for electricity, drainage, and communication were part of each tunnel system. A blast trap was used to protect entrances. This was achieved by having the access to the main communications tunnel turn shortly before entering it so that any blast effect would be absorbed at the end of the tunnel entrance.
Over two dozen gun batteries occupied the Rock during the war, plus positions for Bofors anti-aircraft guns. The largest guns were 9.2-inch guns in six single gun batteries and one two gun battery. There was also a two gun battery of 9.2inch howitzers. Several batteries of 6-inch guns and 3.7-inch anti-aircraft guns mostly in two gun positions, (some of the latter in four gun batteries), supported the larger weapons. Many of these were mounted high on the rock on both sides.
4. Malta
The British set up six battery positions along the main islands' vulnerable southeast coast. Except for beach defenses and the old forts which guarded Valletta and the southern ports of Marsa Scirocco and Birzebbuga, there were few other fixed defenses of significance.
WEAPONS AND EQUIPMENT
Rail Guns and Coast Artillery Range 18-inch (457-mm) (RR) howitzer 100+ km 15-inch (381-mm) gun 38.4 km 43.2 km 14-inch (356-mm) gun 13.5-inch (RR) gun 36.5 km 9.2-inch (234-mm) gun 33.5 km 20.6 km 9.2-inch (RR) gun 13.1 km 9.2-inch (RR) howitzer Location & Number 1939-40 1 near Dover 2 near Dover? 2 near Dover 3 near Dover 21 Southern England, 8 Gibraltar - Southern England - Southern England
Two batteries of 8-inch (203-mm) guns, with a range of 26.7 km, went into service near Dover in 1942. These weapons on barbette mounts had gun shields. A long range 13.5-inch gun named Bruce performed limited service in 1942. It was supposed to have a range of over 100 km, but it had problems similar t
o those of the old German Paris guns with regard to the wearing down of the bore with each shot.
WORLD WAR II
The Local Defence Volunteers organization formed before the Battle of Britain soon became the Home Guard. These poorly armed civilians set up the first roadblocks and interior defenses while watching the skies for paratroopers. After the evacuation from Dunkirk the military hastily prepared to defend the coast under the direction of General Ironside. With few heavy weapons left from the BEF, and much equipment lost, the new commander of the island's defenses, General Brooke, decided not to concentrate his forces on the beaches, but rely more upon the Stop Lines.
Across the Channel the Germans installed heavy guns to bombard the coast at Dover. The British responded with their own weapons which were not as heavily armored or as large a caliber. "Winnie," the first of two 14-inch guns, went into action in the late summer of 1940. The other heavy pieces joined in as they were installed. The dueling continued for much of the war. The final action came in support of the British 2nd Army as it cleared Calais with the Dover guns firing on the German Battery Todt in September 1944.
To invade Britain the RAF had to be defeated first. To insure a shorter supply line the Germans had selected the southeast coast for their invasion, Operation Sea Lion, to be preceded by the use of airborne units. This location would have limited the ability of heavy units of the Royal Navy to interfere with the invasion. The radar stations which ran along and near the coast were part of the defenses which the Germans overlooked. They made it possible for the RAF to win the battle of the skies and make the invasion impossible. If the Germans had been able to send over an airborne division it is doubtful the Home Guard could have stopped it, since regular army units on Crete a year later inflicted heavy casualties on a similar force, but failed to stop it.