Heavy Anti-aircraft gunsite 350m north east of Little Oakley Hall

Reasons for Designation

Although of comparatively recent date, 20th century military sites are increasingly seen as historic survivals representing a defining episode in the history of warfare and of the century in general; as such they merit careful record and, in some cases, preservation. One of the more significant developments in the evolution of warfare during this period was the emergence of strategic bombing in World War II, and this significance was reflected by the resources invested in defence, both in terms of personnel and the sites on which they served. During the war, the number of people in Anti-aircraft Command reached a peak of 274,900 men, additional to the women soldiers of the ATS who served on gunsites from summer 1941, and the Home Guard who manned many sites later in the war. A national survey of England's Anti-aircraft provision, based on archive sources, has produced a detailed record of how many sites there were, where they were and what they looked like. It is also now known from a survey of aerial photographs how many of these survive. Anti-aircraft gunsites divide into three main types: those for heavy guns (HAA), light guns (LAA) and batteries for firing primitive unguided rockets (so called ZAA sites). In addition to gunsites, decoy targets were employed to deceive enemy bombers, while fighter command played a complementary and significant role. Following the end of World War II, 192 HAA sites were selected for post-war use as the Nucleus Force, which was finally closed in 1955. The HAA sites contained big guns with the function of engaging high flying strategic bombers, hence their location around the south and east coasts, and close to large cities and industrial and military targets. Of all the gunsites, these were the most substantially built. There were three main types: those for static guns (mostly 4.5 and 3.7 inch); those for 3.7 inch mobile guns; and sites accommodating 5.25 inch weapons. These were all distinct in fabric, though they could all occupy the same position at different dates, or simultaneously by accretion. As well as the four or eight gun emplacements, with their holdfast mountings for the guns, components will generally include operational buildings such as a command post, radar structures including the radar platform, on-site magazines for storing reserve ammunition, gun stores and generating huts, usually one of the standard Nissen hut designs. Domestic sites were also a feature of HAA gunsites, with huts, ablutions blocks, offices, stores and amenities drawn from a common pool of approved structures. Sites were often also provided with structures for their close defence; pillboxes are the most common survivals, though earthwork emplacements were also present. The layout of HAA gunsites was distinctive, but changed over time, for example to accommodate the introduction of radar from December 1940, women soldiers from summer 1941, and eight gun layouts from late 1942. Nearly 1,000 gunsites were built during World War II, and less than 200 of these have some remains surviving. However, at only around 60 sites are these remains thought sufficient to provide an understanding of their original form and function. This includes 30 of the 192 examples which continued in use until 1955. Surviving examples are therefore sufficiently rare to suggest that all 60 well preserved examples are of national importance.

The Heavy Anti-aircraft gunsite 350m north east of Little Oakley Hall, is a rare survival of its type in the country. The square design of the four emplacements is unusual; although several have been documented for Essex, the four at Little Oakley are believed to be the only surviving examples. The survival of the wooden and canvas ammunition racking within the ammunition recessess is extremely rare and one of only a handful remaining in the region. H5 Little Oakley is one of only nine sites in existence (in any form) from an original wartime deployment of about 40 HAA positions across Essex - a pattern designed to combat German bombers en route to the capital, the Thames estuary and other military targets in the south east of England. It provides a valuable insight into the development of anti-aircraft measures in the region and is a significant, visible reminder of the nature of home defence during World War II.

Details

The monument includes the remains of a World War II Heavy Anti-aircraft gunsite located 350m north east of Little Oakley Hall. The gunsite, documented in wartime records as `H (Harwich) 5, Little Oakley', became operational in 1942 to form part of an extensive deployment of batteries across south Essex. It maintained four Heavy Anti-aircraft guns arranged in a line from north west to south east (against the direction of incoming enemy aircraft) and mounted in square emplacements set at 25m-30m intervals. The emplacements (numbered 1 to 4 from north to south) were built to a single pattern, measuring 13.5m across and protected by concrete walls 0.5m thick and 1.5m high. The two northern emplacements survive largely intact and the southern emplacements both retain substantial sections of surrounding walls. A concrete-covered shelter for the gun crews was built out from the main wall of emplacement 1, and a similar structure is indicated by a concrete floor alongside emplacement 3. Emplacement 4 contains four internal ammunition recesses (covered chambers supported by short internal walls), and two recesses survive in each of the two central emplacements. One recess in emplacement 4 and another in emplacement 2 contain original wooden racking. The racks have three tiers, with three substantial beams apiece to support the weight of the anti-aircraft shells. Some of the beams in emplacement 2 are still clad in a protective layer of canvas. The central holdfast for one gun (a steel socket for the locating spigot on the gun's mounting plate) remains visible, set into concrete in the floor of emplacement 2. The gunsite's main ammunition supplies were stored in six ammunition huts positioned near or between the emplacements. The location of these huts, slightly to the north of emplacement 4, can still be identified and is included in the scheduling. The surviving concrete floor of one of these huts carries the impression of the corrugated sheeting originally used for the superstructure. The gunsite originally included a command post, placed centrally behind the emplacements (to the west), and a range of accommodation buildings situated some 150m to the north east. These structures have been demolished and are not therefore included in the scheduling. Modern telegraph poles are excluded from the scheduling, although the ground beneath them is included.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

32431

Legacy System:

RSM

Sources

Books and journals
Dobinson, C S, Twentieth Century Fortifications in England: Volume 1.3, (1996), 368-9
Nash, F, World War Two Heavy Anti-Aircraft Gun Sites in Essex, (1998), 25-6

Other
Title: TM 2128 Source Date: 1956 Author: Publisher: Surveyor: 1:2500
16 colour prints, Nash, F, Unreferenced, (1998)
RAF, 106G-UK 1492-3090, (1946)
Tyler, S, MPP Film, (1998)

End of official list entry

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