Summary
40mm-Bofors light anti-aircraft gun emplacement, based on a design by the Department of Fortifications and Works and built around 1943 to defend the Bordon Army complex.
Reasons for Designation
The 40mm-Bofors light anti-aircraft gun emplacement, based on a design by the Department of Fortifications and Works and built around 1943 to defend the Bordon Army complex, is scheduled for the following principal reasons:
* Rarity: it is a rare surviving example of a Second World War Bofors gun emplacement of the fieldwork dugout type, which was based on the Department of Fortifications and Works design instructions;
* Survival: the emplacement survives well including its plan, concrete block walls, ammunition stores and predictor pit, the latter suggesting evidence of former fittings;
* Potential: the remains will enhance our detailed understanding of the construction, function and use of the fieldwork dugout type of Bofors gun emplacement in England;
* Period: the gun emplacement at Bordon is strongly representative of the light anti-aircraft defences constructed across England during the Second World War, to defend vulnerable sites from German air attack;
* Historic interest: it is an important and evocative witness to the threat of aerial bombardment at Bordon Camp during preparations for D-Day.
History
The Bofors 40mm was the standard weapon for the home defence of vulnerable sites in static emplacements during the Second World War. It was designed to fire at aircraft and had a firing rate of 120 rounds per minute. Radar was used to identify and locate the aircraft and this information would be relayed to the emplacement where the crew would plot the information into their predictor equipment. The predictor provided ballistic information to the gun crew, who had to keep a set of pointers in a quadrant as the gun was moved to follow the line of flight. Bofors delivery commenced in November 1939, starting with the mobile variant, but static models were soon introduced to speed up production. By 1942, 6,344 had been delivered, although not all were for home defence.
The Department of Fortifications and Works (DFW) provided instructions for the construction of Bofors emplacements, which were simple fieldwork dugouts with revetments of concrete block. The sites were small, slight and highly diverse in their detailed design. Bofors guns were placed on buildings or on purpose-built towers but the fieldwork emplacement was the most common type. The presence of a holdfast (a fixed base with locating bolts) identifies that a site was built for a static gun. The emplacements were usually provided with four ammunition recesses, a predictor pit and an entrance to the rear. A design of 1942 for airfield defence records the following dimensions; an open area of 5m by 6m, with the floor set 0.38m below ground level and made from clinker on a bed of hardcore; the ammunition recesses to be 1.1m wide by 0.61m deep and high. If a holdfast was to be used then this would be fitted with eight holding bolts of 0.61m in length and surrounded by a drum of concrete. Construction was estimated to take 20 hours, when undertaken by 12 men.
Bordon was identified as vulnerable point 818 and the emplacement was one of twelve built, but is thought to be the only example to survive. It was manned and probably built by Canadian gun crews and designed to protect Bordon Camp, Longmoor Camp and the Longmoor Military Railway, which were in use as an assembly area for D-Day. It appears to be based on the DFW instructions, but modified to suit its exact location and purpose. Also nearby, there are the remains of a GL Number 3 Mk2 radar trailer which was used to detect enemy aircraft.
Bordon Camp continued to be used by the Army until the end of the C20, but is now (2020) in the process of being redeveloped and an adventure play park has been installed in the adjacent clearing. The floor of the gun emplacement appears to have been raised by vegetation over the years, but it is not thought to conceal a holdfast.
Details
40mm-Bofors light anti-aircraft gun emplacement, based on a design by the Department of Fortifications and Works and built around 1943 to defend the Bordon Army complex.
PRINCIPAL ELEMENTS: the monument is formed of a Bofors gun emplacement at Bordon, Hampshire, located in the vicinity of National Grid Reference SU 7878035236. The emplacement was constructed in around 1943 on the bank of a heavily wooded area and would have originally had a line of sight south.
DESCRIPTION: the semi-sunken, C-shaped emplacement faces south and is around 4m wide by 5m deep. The emplacement wall is around 1.2m high and is only visible from inside the structure as the outer faces are earth-covered and indistinguishable from the surrounding landscape. The walling is formed of concrete blockwork and there are four recesses for ammunition; one to the western side, one to the south (offset to the eastern side) and two to the east. They are open-topped and around 0.6m wide by 0.6m deep, with two courses of blockwork surmounted by a slab shelf. To the western side of the front wall there is a wide, full-height recess, perhaps designed to allow the gun to be rolled forward as far as possible within the emplacement.
A rectangular predictor pit is situated towards the rear (north-west) of the emplacement and it is separated from the walling by a pedestrian entrance to the west. The pit measures 3m by 2.5m and has a single blockwork step down to the floor. The walls are constructed of blockwork on top of a foundation of five visible courses of brickwork. At the south-eastern corner of the pit, the wall is more substantial, appearing as a plinth of around 0.5m by 0.5m and possibly designed to act as a mount for equipment. The walling to the western side is higher, suggesting a pent roof (no longer present). The rear of the emplacement is open and would have provided access for the Bofors gun to be wheeled in.