Pickett-Hamilton
Fort in elevated position
at Silloth Airfield, Cumbria.
Photograph by JOHN MINNS
In the summer of 1940 many engineering
companies approached government departments with plans for defence structures
designed to their own specifications. The New Kent Construction Company of
Ashford, submitted plans for a "disappearing pillbox" for airfield
defence to the designs of Donald Hamilton FSI, LRIBA.
The design consisted of two precast concrete
pipes, one sliding within the other, one end of each being closed. These were
to be installed on end in the ground at suitable locations on the landing
areas of airfields. When not in use, the concrete lid of the smaller pipe
(rising head) lay flush with the ground surface, but when brought into action
during an emergency, it rose some 2ft 6in above the surface to permit fire
from either of its three loopholes. In the closed position the pillbox was
concealed, it therefore allowed for an element of surprise particularly in
the event of a landing of enemy parachute or airborne troops.
The lifting mechanism consisted initially
of a standard 8-ton aeroplane jack, but as this took 3 minutes for the head
to rise, it was replaced by a compressed air system supplemented by a hand
pump for emergency use (which was quicker to operate).
This pillbox became known as the Pickett-Hamilton
Fort and adopted by the Air Ministry (drawing number 13313/40).
ISOMETRIC SKETCH OF PICKETT HAMILTON FORT
COPYRIGHT `PILLBOXES` by HENRY WILLS
The provision and installation of these
pillboxes was given the highest priority, the Prime Minister himself showing
an interest in the progress of the work. They were soon however, considered
obsolete and provision was discontinued. The main reasons were as follows:
· The structures were not sufficiently
large to accommodate modern weapons.
· They were not strong enough
to sustain the weight of heavy aircraft.
· No upward view was possible
(apart from cursory looks through the entrance hatch).
Pickett-Hamilton forts were due to be delivered
on 31 January 1941 and in a statement prepared by the New Kent Company on
24 April 1942, out of a total of 335 installations, three had been installed
at Middle Wallop.
One of the three standard Pickett-Hamilton
forts at Middle Wallop has been found at NGR 3002 3824 (Monument 535)
A PICKETT-HAMILTON EXCAVATED
by
PETER COBB
Adapted from `LOOPHOLES` NO15
Site Name: PORTSMOUTH
, OLD CITY AIRPORT
Site Type: DEFENCE > PICKETT-HAMILTON
RETRACTABLE PILLBOX
NGR: SU 6732-0390
Location: On sea wall between remnant of
former moat to Hilsea Lines, retained as a drainage channel for former airport
and present housing estate (since this dig this has become a community of
7000 persons) and the footpath on the Portsea Island side of Port Creek.
THE `DIG`
Work commenced on site during the summer
of 1979 and took until February 1981until the final scale drawing could be
done. Persons involved were: Peter & Mrs M. Cobb, Mr G.D.P. Cobb, Mr W.E.J.
Parker, Mr D.J. Godwin, Mr & Mrs P.J. Hand and Mr G.H. Mitchell.
Never were there more than four persons
on site at any one time and twice only one (this was a mistake and very nearly
proved fatal!).
The first task was clearance of brushwood
from both access hatches, installation of pump and the digging of a small
drainage channel into the Creek to take the run-off from pumping.
The second task was to enter the west hatch
and then free the east hatch (which was jammed shut) in order to commence
excavation of the interior. After seven hours the east hatch had been freed
and could be opened, and was propped open for safety and marked to that effect.
The third task was to dig. This took up
the following seven months (allowing for study visits to other sites) and
required the purchase of extra buckets. Work had to stop twice for the site
to be re-pumped as it flooded in heavy rain stroms. Finds (listed hereafter)
were recoreded as part of this task.
Fouth task was to actually survey and drwa
out the site before handing over to Portsmouth City Council for preservation
by sealing down the hatches with a skim of concrete.
The main work could only be done with one,
or at most two, persons at the `face` digging and/or recording, one moving
the spoil safely to the Creek or taking artefacts for retention elsewhere,
and acting as first-aider and safety officer (and often as information officer
for the passing public!).
WHAT
WAS EXCAVATED?
7.25 tonsof
shingle, presumably from long-completed civil engineering works on the
sea wall.
3 skeletons
of dead mammals (1 fox and 2 small dogs)
2 shovels (
1 Military Debris type and 1 civilian, presumably also from the 1960`s
civil engineering works).
6 screw pickets
1 timber beam,
6`6" long x 9"x6", of which more later
3 very rusty
coils of barbed wire
2 buckets (1
battered galvanised iron, stamped 1940 on base and the other an early
moulded rubber with wire and wood handle, again presumably discarded during
the 1960`s work
1 helmet, oddly
of theso-called 1917 Pattern civilian design
17 LIVE rounds
of .45"Martinin Henry ammunition, and
2 fired rounds
(ie. cartridge cases) ditto.
A NEAR MISS!
On the Maundy Thursday military half
leave period 1980 I entered the pillbox alone but put up the warning markers
etc which were by that time stored in waterproof bags in the east hatch as
normal practice, and set about removing the final few shovel` worth of shingle
from under the counterweight block. As I did there was a sudden snapping sound
and, shocked I moved closer to the side of the outer shell. Suddenly the counterweight
block fell four feet or so, coming to rest on the sheet piling shelf and the
inner end of the timber beam mentioned before. The crash was heard (and reportedly
felt) some distance away and within a very few minutes a recovery party from
the workmen on the building site arrived. Thankfully I was OK, apart from
the shock, but the shovel and the last of the shingle are still under the
block. We have learned from that always to go to such sites in pairs (or more)
for safety reasons.
POST EXCAVATION
RESEARCH
Henry Wills and follow-up work at the P.R.O.
(WO199) indicated that the dangers of the counterweight design were such that
only 10 or at most 12 were ever installed. Portsmouth had, for the record,
one of each type, i.e.this one, a compressed air type and the more common
high-lift hydraulic ram type. It is the latter which was excavated in 1983
and re-sited outside the D-Day Museum at Southsea Castle.
The timber beam was ash and, on close examination
by torch the Saturday following the incident above, was found to have the
markings of the R.A.O.C. sawmill at Hilsea. We presume that it had been delivered
here as an aid to installing the counterweight, or to support it while the
wires were tensioned, as the angles were such that it could not have been
got into the pillbox either of the hatches and down underneath the block after
installation into its place of rest. It was placed on edge.
The date square which reads "RR 1941"
was evidently scratched very skilfully by someone nearly a year after the
pillbox`s constuction.
The helmet: this design, according to the
Imperial War Museum, was re-issued in 1940 for use of workers in the aircraft
construction trades as the pressings for it were still extant in the manufacturing
premises in Walsall. This leads to the ammunition, as the perimeter of the
airfield was defended by a Home Guard unit formed exclusively from the employees
of Airspeed Ltd. The exact origin of the ammunition is now lost in time, but
the then curator of the Royal Military Police Museum (whom we heartily thank)
informed us that several of the then-embryonic military and regimental museums
were searched for any firable weapons, and munitions of Home Guard units considered
most likely to have to engage the enemy. Hilsea City Airport Company (or Platoon)
were well within this category as they were on a very vulnerable airfield
within a major port/military zone which would have been a great prize for
the enemy and a great loss, if lost, to our War Effort. He further suggested
that there may have been training carried ou at targets in the Creek from
the pillbox, hence the two fired rounds.
This is a very good posiblity as the News
of Portsmouth has in its archives a series of photographs taken in 1940/41
of the Home Guard on the airport using a wide variety of weapons and in a
number of weird styles of so-called battledress, including modified work overalls
and storemen`s coats as well as more normal issue battledress.
HOW THE PILLBOX
WAS RAISED
The evidence is that the four-man crew
who were to man this type of pillbox would, on a given order, place one foot
each into a 6" x 4" x 4" foothold inset into the counterweight
block and bear down together. As the block came down they ducked under the
rising pillbox and then stood on the block. To get out it appeared that all
four would have to place one foot on a ladder and then step off the block
in unison. There were catches (see drawing) but they appeared very flimsy
- certainly not strong enough to hold the counterweight block down unaided.
What would happen if wires were broken
in action or is a crew member were shot and injured or, worse still, killed?
I can see the counterweight block being
jammed at an awkward angle or even rendered useless. Worse, the unsupported
pillbox might crash down, thus trapping the occupnts. This, perhaps, was why
so few of this type were built.
The sump was only sufficient to cope with
a small amount of water - about seven gallons - and no pump (or evidence for
such) was ever found, so we believe that the galvanised bucket found on site
was for bailing it out.
