VERSTÄRKT FELDMÄSSIGE bauten im bereich AOK15
Immediately after the Germans had occupied the North Sea, Channel and Atlantic coats and the French campaign had been completed, they started preparations for the invasion of Britain. Thus, the Kriegsmarine started military infrastructure and defensive works in many ports. Since the Kriegsmarine did not have sufficient construction forces, however, the Heer was requested to help with its Bautruppen.
The first defensive works consisted mostly of field fortifications (feldmässig) (constructed in wood or brick) or light semi-permanent concete constructions (verstärkt feldmässig) with a wall and ceiling thickness of 30cm (Ausbaustarke D, splittersicher or schrapnel-proof) or 60cm (Ausbaustarke C, schusssicher or shell-proof.).
Thus, in July 1941, the following mostly schraprnel-proof semi-permanent constructions (30cm) had been built and were still planned along the Belgian coast:
Things changed dramatically, however, in December 1941, when Hitler released his directive Küstenverteidigung (14 December 1941), in which he ordered a "neue Westwall" to be constructed along the coasts from Norway to the French-Spanish border. OBWest, Generalfeldmarschal von Rundstedt immediately began organising coast defence of his territory. Thus, in May 1942 he subdivided the coastline into coastal sectors or Küstenverteidigungsabschnitte, each with one or more divisions. Local commanders then started thinking about which kind of defensive constructions they wanted. To assist them, the office of the Inspektor der Landesbefestigung West had designed several semi-permanent (verstärkt feldmässig) bunker types with walls between 1 and 2 metres thick. For the construction of bunkers use was made of a standard construction types. The big advantage of the bunkers was that their design was relatively simplistic, so that intervention by the Organisation Todt was not necessary and the troop engineer units were able to build the constructions themselves.
The designs were ranged in a series called Vf (short for verstärkt feldmässig) and numbered between 1 and 7. Subtypes, differing in construction strnegth and method were indicated with the suffixes a-d. In Februaty 1942 the following Vf-designs were thus released:
The original German document for the above constructions can be found in the file below:
These 18 designs were distributed to the Festungspioniere in March 1942. All constructions were of very simple design, consisting of one or two rooms. In normal circumstances the 1m designs (splittersicher or shrapnel-proof) were to be constructed, with the 2m-designs (schusssicher or shell-proof) for exposed positions.What also set them apart was the constrution of the ceiling, either with Hoyerbalken (beams of pre-stressed concrete) or Wellblech (corrugated iron). The designs enabled four basis functions to be protected: personnel (6), ammunition (4), MG (3), AT-weapons (2) and observation (2).
Of these Vf bunkers thousands would be built between the spring an autumn of 1942. Missing from the avove list werecommand and hospital bunkers. For these functions the Westwall designs 117, 118 and 119 could be built.
In spite of the above 'catalogue' to choose from, local commanders still wanted to protect more specific functions which were not yet accounted for, more specifically water supplies and toilet facilities.
In June 1942 and in the absence of designs from Berlin, the Festungspionierkommandeur XVIII (responsible for the Netherlands and the AOK 15 area) himself designed a series of water supply and latrine bunkers.
June 1942 also saw the introduction of the Tobruk. This low-tech but highly-efficient type of fortification had been used for the first time by the Italian army during the siege of Tobruk in April 1941. The Italians had placed their machine guns in nearly invisible, open, circular, concrete cylinders, often connected to open trenches. In March 1942, the Inspekor der Landesbefestigung Nord introduced them in Norway. But it was the Inspekor der Landesbefestigung West who, in June 1942, proposed a circular position or Ringstand for one machine gun, which could also be used for observation purposes. He designated the type Vf8, consisting of an actogonal pit with an 80cm round opening on top and a small rectangualr sheltering room for 2 men.
Also in June 1942 a further series of Vf-bunkers were issued. These had been designed not by the Inspektor der Landesbefestigung West, but rather by the office of the General der Festungen und Pioniere. These designs were numbered 51a - 57a and 59a. Interestingly, the prefix Vf was not used here.As could be expected this series was an improvement of the earlier series. Most importantly, the Hoyerbalken were replaced by iron I-beams. Changes were also made to the AT-gun garages and the observation posts. However, the series also constituted an extension, with a a dressing station being added. The details of this series are as follows:
Remarkable in the above list is that all types were of the splittersicher type only. Also, in the types 56 and 59a a Tobruk was integrated for observation purposes.
A report of June 1942 mentions 833 Vf-bunkers having been constructed along the Belgian coast.
Further developments in the design of Vf constructions took place in autumn 1942. At this point the Vf25 Fundament für Panzerkampfwagentürme design was released. This was a further development of the Vf8 Tobruk but now adapted to mount captured ex-French tank turrets. The success of this design lead to a flurry of Tobruk types in the following years on which captured French, Soviet, British, but also German tank turrets could be mounted. Also, the Ringstand concept was further adapted to house mortars, flamethrowers, guns, observatories and signalling posts. Suffice it here to say that the Ringstand was so popular that it was constructed in huge numbers. Most of these were of the type 58c (octagonal)(the type 58d bieng round). This type, released in autumn 1942, would be built in tens of thousands by the end of the war.
3 Vf bunkers constructed in the AOK15 area
The following provides an overview of the minimum number of Vf-bunkers constructed in the AOK15 area of operations. The list is based on Rudi Rolf (2014). The actual numbers and the exact locations of these bunkers will be checked by in more detail at a later stage: A similar exercise for the permanent bunkers revealed a serious discrepancy between the two numbers.
The intoduction of the building programes for permanent (ständig) constructions did not mean the end of the semi-permanent constructions, however. The latter would continue being built until the end of the war, thus simultaneously with the permanenet constructions. Their construction, however, was subject to 3 conditions: they could only be built if 1) sufficient volumes of concrete were available (so not at the expense of the permanent constructions), 2) they were perfectly camouflaged (thus offsetting their vulnerability) and 3) they were not located where a permaenent bunker was planned later.
The continued building of Vf -bunkers meant, for example, that the following numbers had been built/were beig built along the Belgian coast an in the Antwerp sector in May 1944:
It is important to note that the above overview includes ALL Vf-bunkers of ALL construction strength (thus ranging from 30cm to 2m), and not just the standard types mentioned in the tables above.