Details

The monument, which includes a World War II Heavy Anti-aircraft (HAA)
gunsite and its associated domestic camp, is situated at Sinah Common
approximately 700m north of Hayling Bay. The gunsite, known as Sinah or P2
(Portsmouth 2), formed part of a chain of batteries positioned to defend
the industrial and military targets of Portsmouth. As the size and shape
of Hayling Island closely resemble that of Portsmouth, the island was set
up as a decoy to distract enemy aircraft from the city. In April 1941
Hayling Island received over 200 bombs and parachute mines, and the
gunsite was hit directly, killing six of its crew members. The gunsite
remained out of action until December 1941. It was then equipped with a GL
Mk II radar and in April 1942 was amongst the first to be fitted with a
paraboloid aerial replacing the Ground Laying mat. In January 1946 the
battery was selected to form part of the reduced, post-War layout known as
the Nucleus Force, with its guns held in readiness off-site.
The four 4.5 inch gun emplacements are situated at the western end of the
site along a semicircular road with direct access from Ferry Road. They
surround a control building, which has been mounded over, but which will
survive as a buried feature. Sources indicate that the gun emplacements
were numbered 1 to 4 from south to north. They were octagonal in shape
with six ammunition recesses fitted along the concrete blast wall
surrounding the holdfasts. Emplacement number 1 is well preserved, despite
its southern tip subsiding into the adjacent pond as a result of
quarrying. At its centre securing bolts protrude from the holdfast, while
all six ammunition lockers are present, equipped with internal recesses in
which wooden shelfs were fitted. Contemporary stencilling on one of the
lockers reads the angle measurement 75 degrees, indicating the position of
the gun at this angle. Immediately north of emplacement number 1 is a
generator room, which was damaged during the 1941 attack, leaving a large
hole in the roof. Original cables remain embedded in its northern wall.
Emplacements numbers 2 and 3 have been substantially altered to provide
sheltered seating; the back gates have been filled, the adjoining storage
bunkers were closed off, and all ammunition lockers removed. Surfaces were
plastered or paved over and benches were placed along the blast walls.
Emplacement number 2 was heavily damaged in 1941 and a small plaque,
installed in 1994, commemorates the men of the 219 battery, 57th Heavy
Anti-aircraft Regiment, who were killed in action. Emplacement number 4
was infilled in the late 1960s, but will survive as a buried feature
underneath the mound.
The emplacements were served by two ammunition stores; one at the northern
end of the site along Ferry Road and the other at its southern extremity
near emplacement number 1. These five-bay magazines were protected within
blast walls, which proved effective during the 1941 attack. Although the
blast wall at the southern end of the site was damaged, the magazine
remained unscathed and the glass in its windows survives. About 100m east
of the magazine on Ferry Road is a red brick flat-roofed gun store, which
has been refurbished with new doors, ramp, guttering and roof, and is now
in use as a powerhouse.
A track connects the emplacements and the domestic camp at the eastern end
of the site. The general layout of the domestic quarters is apparent from
the concrete roads, which come off the main entrance at Ferry road. Along
the southernmost track is a concrete standing which probably functioned as
a parade ground. In the north eastern corner of the site a concrete air
raid shelter is preserved, which has been bricked up. On its roof are two
small domes covering air vents. The gunsite was surrounded by a fence, of
which some of the original posts survive.
The following items are excluded from the scheduling: all later surfaces,
fences, gates and structures (including bollards, bins, interpretation
boards and Pay and Display machines), and all later materials and
equipments stored within the site. However, the ground beneath these
features 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.

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 World War II Heavy Anti-aircraft gunsite (P2) at Sinah Common, 570m
south east of Sinah Farm is well preserved and will contain a wealth of
archaeological evidence relating to the construction and usage of the
site, which spanned two main periods: World War II and the early Cold War.
Its remains, which bear the marks of bomb damage, provide a testimony to a
crucial period in British history, which has been largely erased
elsewhere. Its significance is futher enhanced by its association with the
bombing decoy south of the gunsite, as well as World War II defences along
the southern coast of Hayling Island, such as pillboxes and anti-tank
defences.

Source: Historic England