Details

The monument includes the standing, earthwork and buried remains of a World
War II HAA (Heavy Anti-aircraft) gunsite initially known as Station J and
then Station H9 from 1 August 1941 onwards. It includes the full extent of the
original station complete with four gun emplacements and associated
structures, as well as the remains of the domestic site.
Station J is first recorded on 19 September 1939 when 286 Battery of 91 HAA
Regiment(286/91 Bty) received two mobile World War I vintage 3in guns from
Station C, west of Preston. By the end of September 1939, control passed to
172/62 Bty which is thought to have constructed permanent gun emplacements
considered necessary for the two 4.5in guns. These were certainly in place by
9th May 1940, when 286/91 Bty took over. On 25 July 1941 Station J, called H9
from 1 August, returned to the control of 172/62 Bty until 19 February 1942
when 113 HAA Regiment took charge. On 22 June 1942 four 3.7in static guns
supported by a GL MkII radar were reported to be at Station H9. In September
1942, the gunsite was passed to 510/151 Bty. This was a mixed sex battery
which used women from the Auxiliary Territorial Service (ATS) to operate
radar, communications systems and other support roles whilst the men operated
the guns. That same month the station was credited with shooting down an enemy
aircraft, a relatively rare event. The gunsite was abandoned in November 1944
when both equipment and personnel were moved to a new gunsite at Ringborough
on the coast for Operation Diver which countered the new threat from the V1
flying bomb. The gunsite is not thought to have been reoccupied as it was not
one of those chosen to form part of the post-war Nucleus Force, the spread of
192 HAA gunsites in England selected to be retained after the war.
The functional core of the site are the four gun emplacements and the command
post towards the south eastern end of the monument. The command post is a
complex concrete structure about 20m by up to 7m, facing south with its long
axis orientated east-west. The shell of this building is very well-preserved,
retaining some additional fittings such as metal ventilators. It is thought to
be an early design and does not follow the pattern typically used from 1941
onwards. Most of the structure is open to the sky, outlined by low walls and
formed platforms for the identification telescope, height finder and
predictor; three pieces of optical equipment for spotting and tracking enemy
aircraft. At the centre of the command post there is also a concrete post
which was the mounting for an anti-aircraft machine gun designed to engage
low-flying aircraft trying to attack the gunsite. The command post also
includes three semi-sunken rooms, the largest is at the west end with two
smaller rooms on the north side towards the middle of the command post. The
largest room is interpreted as the plotting room where data from the height
finder and predictor were converted into elevation, bearing and fuze timings
for the guns. Of the two smaller rooms, one would have acted as an office
whilst the other, which shows evidence of later alteration, would have been a
boiler room for central heating. This had to be installed on gun batteries
with female staff. Arranged in an arc around the south western side of the
command post there are the four gun emplacements. These are all of a general
design first issued in 1938 and are constructed in concrete. Each emplacement
is approximately 12m across and octagonal in plan which is defined by a blast
wall. Set centrally into the concrete floor there is a ring of holding down
bolts for the gun mounting and extending inwards from six sides of the blast
wall there are six 2 sq m ammunition lockers. The remaining two sides of
the blast wall form wide entrances set on opposite sides of the emplacement.
Each emplacement also has a small concrete shelter immediately on the outside
of the blast wall. This is identified as a relaxed duty shelter for the crew
when not on alert. The four emplacements appear to have been built in at least
two stages. The southern pair of emplacements retain metalwork, including
hinges for blast doors across the entrances and for the ammunition lockers, as
well as fittings in the top of the blast walls for securing camouflage
netting. In addition some of the ammunition lockers retain their original iron
doors. The northern pair of emplacements show no evidence that they had either
hinges for doors or fixings for camouflage. Also two of the ammunition
lockers, the central one on each side, are latter additions to the
emplacements. The emplacements are generally very well-preserved, some even
retaining some timber work, however the southern emplacement of the northern
pair has been partly demolished. Opposite the command post and 15m to the
south of the southernmost pair of emplacements, there is a five bay ammunition
magazine surrounded by a substantial blast wall. The magazine itself is flat-
roofed, approximately 10m by 3.5m, complete with three doors and two windows
regularly spaced down its north side. It follows a standard design produced by
the Air Ministry in February 1939. To the east of the gun emplacements there
is another well-preserved small flat-roofed building complete with its doors
and windows. This follows another standard design and was a gun store, used
for gun maintenance and for storing tools and spare parts. Immediately to the
north east there is a concrete engine bed which is interpreted as the mounting
for the on-site electricity generator. The gun store is at the end of a
concrete roadway which ran past the gun emplacements, connecting them to the
road to the north west. This is also an integral part of the monument and
retains some patches of a tarmac skim applied during the war to make the road
less obvious to enemy aircraft. At the north end of this roadway there are the
remains of the domestic site. On the east side of the road there is a 3m by 4m
brick building with a flat concrete roof. This is identified as an electricity
substation, linking the domestic part of the gun battery to the generators at
the western end of the site, as Sunk Island was not connected to the national
grid until the 1950s. The adjacent disused wooden telegraph pole is also
included in the monument. On the west side of the road, marked on the 1:10,000
map, there is a complex of brick buildings, two main structures with
corrugated iron roofs, with additional smaller linking buildings, porches and
outbuildings with flat concrete roofs. The two main buildings are of different
designs. The one nearest the road is a six bay 24ft span Nissen which measures
10.8m by 7.3m. Most of its curved roofing structure is intact, although a
number of the corrugated iron roof sheets are missing. Its north gable brick
wall is leaning outwards and the southern wall has collapsed. This is believed
to have been the canteen hall. The other main building is a six bay Ministry
of War Production (MOWP) Standard Hut, built in brick with concrete
lintels and metal framed windows. Overall it measures approximately 6m by 11m.
This is in better condition than the Nissen hut although the southern half of
its roof has collapsed with part of the southern gable. This building is
identified as the battery's cookhouse. The various smaller concrete roofed
buildings are much better preserved than the two with iron roofs and are
believed to have been small stores and entrance lobbies. The demolished
remains of another brick building lies 50m to the east. This, marked as a
still extant building on the 1:10,000 map, was the wash house for the site.
These buildings formed part of the domestic camp for the battery's staff with
sleeping accommodation provided in at least 15 adjacent temporary huts
that were removed some time after 1947. Just inside the gate to the field, on
the south west side of the road, there is a 3m by 6m concrete hardstanding
which is interpreted as the foundation for a guard hut.
A number of features are excluded from the scheduling; these are all modern
fences, gates, and water troughs; although the ground beneath these features
is included.

MAP EXTRACT
The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

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 at Stone Creek is the best preserved example
in the East Riding, with nearly a full layout of the station complete with
well preserved emplacements, and other features like the command post and
magazine. The remains of the domestic camp, although ruined, are an especially
rare survival as at most other sites these buildings have been totally
cleared.

Source: Historic England