Coastal artillery
Introduction
The Dutch had quite a score of coastal artillery batteries along the extended Dutch coast-line, on some of the most valuable islands and even along some of the strategic waterways. In this section those coastal batteries shall be addressed.
The artillery along the Dutch coast was divided over two seperate commands. The largest and most batteries fell under the Regiment Coastal Artillery, the remaining coastal artillery defences were navy batteries. Both have been incorporated in this section.
The Regiment Kustartillerie
The Dutch Regiment Kustartillerie [Coastal Artillery] had been founded in 1814, shortly after the French occupational forces had left the Netherlands. The French coastal defences - necessary to keep the Anglo-Prussian forces out of the Netherlands - were gladly taken over.
In 1940 the Regiment counted a mere 5,000 men, of which about 300 men were transferred to 8-staal batteries weeks before the invasion. The Regiment was part of the army and not - like many people think - of the navy, although some navy coastal batteries were indeed part of the navy and manned by navy personnel. But those came on top of the regular coastal artillery units of the Regiment.
The Regiment was divided in two battalions, I-RKA [Den Helder, Terschelling, IJmuiden and Kornwerderzand] and II-RKA [all other locations] as well as a number of depots [school personnel and recruits]. The Regiment operated guns in the calibres 5 cm, 7.5 cm, 12 cm, 15 cm and 24 cm.
Coastal Artillery batteries - north and central
In the depots two guns were in use for schooling purposes. Usually the recruits received their advanced training at the active batteries where they would serve under when graduated.
In the northern theatre were sixteen batteries. Nine fell under the Position Den Helder. Six batteries at Ymuiden and one battery at Kornwerderzand and one at Den Oever.
In the position Den Helder were five batteries of 15 cm [9 x 15 l.40; 6 x 15 l.35], three of 7,5 cm [9 x 7 l.40] and one battery of 12 cm [3 x 12 l.40]. The last four batteries were positioned on the island Texel, of which the defence fell under the Commander position Den Helder.
Ymuiden - that not only had a considerable harbour but also the entrance of the Noordzeekanaal [Nortsea channel] leading to the harbour of Amsterdam - had two batteries of 12 cm [6 x 12 l.40], two batteries of 7,5 cm [6 x 7 l.40] and one battery of two 15 cm guns [15 l.30] within the confines of the harbour fortress Ymuiden. That fortress also house a large battery of five 24 cm guns [24 l.30], but these had been abolished during the mobilisation.
At Kornwerderzand - the formidable casemate fortress on the eastern side of the Afsluitdijk [the causeway between the provinces North-Holland and Friesland] - housed three guns of 4,7 cm. These were manned by gunners of the Regiment Coastal Artillery, but the guns were (with exception of one navy gun) army material.
In the sector at Hoek van Holland [Hook of Holland] - on the mouth of the Nieuwe Waterweg connecting the vast Rotterdam harbours with the Northsea - were six Coastal Artillery batteries. Two batteries of 12 cm [6 x 12 l.40], one of 15 cm [3 x 15 l.40] and one of 7,5 cm [3 x 7 l.40]. Besides on the fortress at the Hook a battery of four 24 cm guns [24 l.30] and a battery of two 15 cm [15 l.30].
This amounts to a total number of activated guns of: 4 x 24 cm, 22 x 15 cm, 15 x 12 cm, 12 x 7,5 cm and 3 x 4,7 cm. A grand total of 56 guns.
Coastal batteries - south
Along the shores of the Haringvliet and the Hollandsch Diep, the wide waterway that was crossed by the Moerdijk bridges and in earlier days a strategic waterway due to its many navy ports, three batteries were to be found.
At Hellevoetsluis two batteries of 7,5 cm [6 x 7 l.40]. At Numansdorp (opposite of Willemstad) one battery of three 7,5 cm guns [7 l.40].
The other batteries in the south were all situated in Zeeland:
At the island Schouwen-Duivenland one battery of three 7 l.40 guns, of which also one battery at Flushing (harbour) and Nieuwe Sluis.
At Westkapelle - island Walcheren - a battery of three 12 l.40 guns. Also at Walcheren - at the locations Dishoeck and Oostkapelle - each a battery of three 15 l.40 guns.
The above figures add up to a total of 6 x 15 cm, 3 x 12 cm and 12 x 7,5 cm. A grand total of 21 guns.
Inland batteries
There were two inland batteries manned by the men of the Coastal Artillery. Both fitted with three 7 l.40 guns. The first one on the south slope of the Grebbeberg defending the Rhine and the second one at Ochten [southside of the Betuwe-line] defending the Waal river. Six 7,5 cm guns in total.
The Navy artillery batteries
Next to the main batteries of the Coastal Artillery there was quite a score of navy artillery too. These batteries were usually for the nearby harbour defences and of the smallest calibres, like 3,7 cm, 4,7 cm and 7,5 cm. Navy batteries were manned by either navy constables or marines.
In the north at Den Helder and the islands as well as the Afsluitdijk defence there were quite a number of navy batteries. The navy harbour at Den Helder was protected by six guns of 7,5 cm [7 l.40] and two guns of 3,7 cm.
At the island Texel two navy guns of 7.5 cm used for AA duty near the seaplane base De Mok on the island. Two semi-automatic 7,5 cm guns against maritime targets too. At the island Vlieland was a navy battery of three 7,5 cm guns [7 l.40] and a battery of three 15 cm guns pointed into the strait between Vlieland and Terschelling. At the island Terschelling was a battery of three 7,5 cm guns in the northwest of the island as well as a 3,7 cm battery at the seaport entrance.
Navy batteries elsewhere in the North were seen at the Wons-line (east of the Afsluitdijk in Friesland) where on 10 May 1940 four 3,7 cm guns manned by navy personnel were manned. A same battery was sent on that day to the position halfway the Afsluitdijk, at Breezand. At the mirror fortress of Kornwerderzand, at Den Oever on the west side of the Afsluitdijk, two semi-automatic guns of 7,5 cm. In the small harbour of Den Oever two 4,7 cm guns.
All in all the northern coastline had nine navy batteries positions along the coast or at harbour entrances. These nine batteries were formed by 3 x 15 cm, 16 x 7,5 cm and 5 x 3,7 cm guns. Inland or at inland waterways another four batteries, comprising 2 x 7,5 cm, 2 x 4,7 cm and 8 x 3,7 cm guns.
At Scheveningen harbour one battery of three 4,7 cm guns (on concrete platforms).
In the position Hoek van Holland four navy batteries. One 4,7 cm battery of two guns and two batteries of four 3,7 cm guns each at the Berghaven [main quays of the position]. One battery of 7,5 cm [7 l.30] defending the Nieuwe Waterweg [main waterway to Rotterdam], about one mile inland from the coast.
As such in the central sector five batteries comprising 3 x 7,5 cm, 5 x 4,7 cm and 8 x 3,7 cm guns.
The last of the navy batteries were located in the province Zeeland, in the harbour of Flushing. One battery of three 7,5 cm [7 l.40] guns at the entrance of the harbour and one battery of two 3,7 cm guns inside the harbour at the main sluice.
The stationary navy land-battery guns that were in service on 10 May 1940 add up to the following numbers: 3 x 15 cm, 24 x 7,5 cm, 7 x 4,7 cm and 23 x 3,7 cm. Altogether 57 guns.
Gun characteristics
It shall probably be interesting to look into the performance envelopes of the most commonly used guns of the Coastal and Navy gun batteries. Therefore we shall describe the characteristics of the 24 cm long 30, 15 cm long 40, 12 cm long 40, 7,5 cm long 40 and the 4,7 cm long 50 guns.
The calibre notification 15 cm long 40 stood for 15 cm barrel cross section [generally referred to as calibre] and 40 times the calibre indicating the barrel length. E.g. 15 cm calibre and a barrel length of 600 cm.
The 24 cm long 30 guns were turret mounted guns, installed on the Fortresses at Hoek van Holland and Ymuiden. In the last position they had been taken out of service in 1940, but the Hoek van Holland battery was alive and kicking. The guns originated from the old Dutch navy battery ships. It were Krupp guns dating from the 19th century. The maximum range of the HE grenades was 8,000 m. The fire rate extremely low with one round every four minutes.
The 15 cm long 40 were Krupp guns. They were capable of delivering HE shells over a distance of 14,200 m. It was capable of rapid fire, e.g. around 8-10 rounds a minute.
The 12 cm long 40 types 1 and 2 were the most commonly used guns, and also Krupp products. There maximum ranges were 12,500 m with the posibility of producing rapid fire 8-10 rounds a minute.
Both the 7,5 cm long 40 guns were rapid fire guns for short distances. These Krupp guns were effective up to a mere 5,000 m.
The 4,7 cm long 50 was a HIH Siderius (Dutch) product. A very capable gun, developed for anti-tank warfare and casemate duty. It was capable of penetrating 50 mm of armoured steel at 1,000 m, which was a quite formidable performance bearing in mind that the design was of the early thirtees. It was effective up to 2,500 m and could produce 15-20 rounds a minute.