Summary

The Priorlancy Rigg Engine Test Area, 1957.

Source: Historic England

Details

The Engine Test Area at Priorlancy Rigg lies 1.8km north-west of the Component Test Area taking advantage of a gently rising east-west oriented ridge. The remains of the four test stands are set into the ridge and dominate its crest. Below are the remains of the effluent system built to collect vast quantities of waste cooling water and unspent fuel. The engine tests were controlled remotely from a control room to the east that was also used for monitoring the test firings and there are four earthwork observation posts to the north.
Building references in brackets cross refer to the English Heritage survey.

Control Room
The control room (A11) from where all the test firings were monitored and controlled, is a single storey, freestanding, rectangular, concrete bunker. It is entered from the east through double doors, and also on this side are a vent and two bays closed by modern wooden panels. Close to the entry doors is an original light pillar. On its southern side is an emergency steel escape door with a passage leading through the surrounding protective earthwork mound. The latter is retained to the rear by a vertical concrete wall, which creates a narrow passageway between itself and the bunker. Observations of the stands were made from the five observation ports in its western wall of the building through five episcopes which remain fixed to the building’s exterior. Alternatively the firings could be watched through four submarine type periscopes that passed through the roof, now marked by four mounting plates, now covered. Internally, the bunker retains its original layout.

On the north side of the bunker and accessed from the passageway, there is a c.100m section of an underground instrumentation duct (A8) that linked the control room to the test stands. This is a 2.9m square concrete tunnel which carried command and mentoring cabling to the test stands. On the surface its eastern end it is visible as the mound of a linear earthwork.

Engine Test Stand (A1)
This was the largest of the stands and was used for the first full rocket firings before the completion of the Greymare Hill Missile Test Area. A vertical concrete wall 11.73m in height forms the rear of the stand. Projecting from either side is a perpendicular concrete wall each incorporating two columns that together supported the stand’s superstructure. At the base of the rear wall are three sloping concrete ramps, now partly covered by dumped rubble. These supported the steel efflux bucket that deflected the flame from the rocket engines through ninety degrees and down the concrete flameway. A gimballed mounting that survives in place just below the lip of the stand was probably attached to the deflector. During firing it was essential for the efflux bucket to be constantly cooled to prevent it from melting. A vast quantity of water was pumped to the stand through two large bore pipes located to the west of the stand. The flow of water to these pipes was regulated by an adjacent brick valve pit accessed via a concrete stairway from near the base of the stand. A second flight of concrete stairs runs up the west side of the stand to a small platform adjacent to which, mounted on a steel bracket, is a galvanised metal tank. On the slope above this is a concrete box with sloping sides.

Below the stand is a sloping concrete flameway, or spillway, which channelled unspent fuel and cooling water southwards away from the stand into an effluent conduit. The lower parts of the channel are lined with sloping concrete panels at their base. In the late 1960s, the flameway was used to test gas pipes; two large diameter steel pipes with cut off steel channels set into the concrete represent this activity.

In the event of an emergency the highly volatile rocket fuel, liquid oxygen and kerosene, could be rapidly dumped. To the south-east a pipe led to the kerosene dump tank (A33/1); the latter is visible as an octagonal concrete base surrounded by a square concrete bund. To the west a pipe was carried on a series of square concrete supports to a square platform, below this is the LOX dump tank marked by a trapezoidal concrete reservoir with sloping sides. Immediately above the test stand is a hard-standing or causeway area. Two rails set into the concrete were used for manoeuvring the rocket engines into place. A number of ancillary buildings associated with the test stand were also located here and their positions are visible as concrete floor slabs, some of which display details of their internal arrangements. To the east of the rails are the remains of the pneumatic control station (A16.1) and immediately west of the rails are the remains of the electrical control station (A17.1). To the north lie the terminal and power house (A35), and immediately to its west was the heating plant house (A 40.1).

As described above, during test firings the stands were dowsed with vast quantities of cooling water, which was channelled down the concrete spillways and into a series of concrete drainage channels. These pass under the lower access road at the base of the stands to a common concrete lined east-west oriented drain. To the south-east lies the rectangular, reinforced concrete, 200,000 gallon effluent lagoon (A14) into which the drain emptied; within it is a central longitudinal dividing wall. Immediately to the east of the lagoon lies the waste kerosene system (A14.1) visible as a small square brick built kiosk. To its west is a concrete bund, and internally there are six concrete plinths arranged into lines of three.

Engine Test Stand (A2)
The layout of this test stand is essentially similar to A1, comprising a concrete base on top of which was mounted a steel-framed tower. At the rear of the test stand is a vertical concrete wall 11.73m in height from which two concrete walls project on which were four columns, which in turn supported the feet of the tower. Its supports were formed of square section hollow steel legs that were filled with reinforced concrete; these are retained to the west at the base of the test stands.

Projecting at right angles from the base of the rear wall are three sloping concrete walls that supported the steel efflux bucket. At the base of the sloping walls are cut-off steel channels indicating the positions of further supports for the efflux bucket. Two large bore steel pipes, which supplied cooling water to the deflector are visible to the east of the stand. These are accessed via a flight of concrete steps close to the rear wall of the stand and were controlled by a square brick valve pit that lies to the east. Two steel channels are attached to either side of the front face of the stand, linked by a guide rail across the front of the stand.

To the west a flight of concrete steps leads up the side of the stand to a small platform on which is a metal tank. Above this is a lagged galvanised metal pipe. On the eastern side of the flameway a flight of steps leads to the crest of a slope and an expanse of concrete. Below the stand is a sloping concrete flameway, or spillway, which channelled unspent fuel and cooling water away from the stand into an effluent conduit to the south. Its lower parts are lined with sloping concrete panels at the base of which further channels drain away from the test stand.

From close to the western foot of the stand a flight of concrete steps provides access to a LOX dump tank. Two lines of square concrete supports lead from the west side of the test stand to the tank, which comprises a sunken concrete, trapezoidal pit. Beneath this feature, at the base of the slope was the kerosene dump tank (A33/2), it is marked by an octagonal concrete base with a central hollow that is now in-filled with sand. This is surrounded by a square concrete bund capped by a low brick wall.

Above the test stand is a concrete hard-standing which was used for manoeuvring the engines into position. Set into this are two steel rails, also on the hard-standing were a number of ancillary buildings. These have been levelled but their remains are visible as concrete floor slabs. Immediately east of the rails was the Pneumatic Control Unit (A16.2), on the opposite side of the rails was the Electrical Control Station (A17.2). To the north was the Heating Plant House (A40.2).

Engine Test Stand (A3)
At the rear of the test stand is a vertical concrete wall 11.73m in height but this differs from stands A1 and A2 in that it is partly brick built. From the rear wall are two projecting concrete walls that originally supported four columns, which in turn supported the feet of a tower. Various fittings remain attached to the rear wall of the test stand including small bore pipes that carried electrical wires, galvanised metal cable channels and junction boxes. The stand was also earthed against static and lightning; brass attachments for lightning straps are also visible on the rear wall.

Projecting at right angles from the base of the rear wall are three steeply sloping concrete walls, which supported the steel efflux bucket that deflected fames from the engine down the flameway. At the base of the sloping walls are cut-off steel channels indicating the positions of further supports for the efflux bucket. Two large bore steel pipes, which supplied this cooling water to the bucket are visible to the east of the stand. The pipes were accessed via a flight of concrete steps on the east side of the stand. Another flight of concrete steps leads up the west side of the stand to a small platform. On the east side of the flameway is another flight of steps leading to the crest of the slope and a small expanse of concrete. Below the stand is a sloping concrete flameway, or spillway, which channelled unspent fuel and cooling water away from the stand into an effluent conduit to the south. Its lower parts are lined with sloping concrete panels at the base of which are further channels that drain away from the test stand.

Close to the west foot of the stand a flight of concrete steps leads to two converging rows of concrete blocks that once supported pipes carrying liquid oxygen from the stand to an emergency LOX dump tank, which survives as a trapezoidal concrete pit.

Above the test stand is a concrete causeway, which was used for manoeuvring the engines into position. Set into this at right angles to the face of the stand are two steel rails. To either side of the causeway were a number of ancillary buildings whose positions may be traced as concrete floor slabs, some with traces of internal features. Immediately east of the rails was the pneumatic control station (A16.3) and to the west was the electrical control station (A17.3). To the north was the heating plant house (A40.3).

Engine Test Stand (A4)
This was the last to be constructed. The remains represent an innovative British design comprising two pre-stressed concrete walls, two sets of pre-stressed concrete brackets and two pre-stressed concrete hangars for the LOX tank. A stainless steel plate bearing the engine mountings was stuck with epoxy resin to a pre-stressed concrete beam that took the thrust. This was probably the earliest use of epoxy to bond steel and concrete together. To the rear of the tower was a steel-framed lifting gantry which handled the rocket engines.

On the hard-standing above the test stand are a number of traces of the ancillary features, these include a 1.3m in wide channel, now filled with hardcore, the footing for two electrical junction boxes, and at the south-east corner, the foundations of a small brick building. Below, and to the south, of the test stand is the sloping concrete flameway with sloping sides, which channelled unspent fuel and cooling water away from the stand into the effluent conduit. To the south-east a line of concrete support blocks leads to a trapezoid concrete LOX dump tank and to the west another line of concrete support blocks also leads from the west side of the stand down slope to a kerosone dump tank, whose concrete foundations remain.

Observation Posts (A21.1, A21.2, A21.3 and A21.4)
To the north of the stands is a line of four Observations Posts; these are reinforced concrete structures covered by earthen mounds with a single internal compartment and entered from a single, rear steel door. The remains of periscope mountings survive on the roofs of two of these (A21.1 and A21.2).

Extent of scheduling
01 Control Room and associated features: to the east the scheduling boundary follows the eastern face of the concrete revetment wall. Towards its south end it follows the bottom of the outer revetment mound around the southern and western sides of the control room. The boundary turns west to follow the base of a linear earthwork bank, which marks the position of an underground cable channel. At the access road the boundary turns northwards and follows the bottom of the northern side of the linear earthwork and at the north east corner it follows a concrete revetment wall.
02 Four engine test stands and associated features: the east side follows a modern steel post and wire mesh fence down the hillslope to the top of scarp defining the cut for the access track. It then follows the outer northern and eastern edges of the concrete bund surrounding the kerosene dump tank (A33.1). From here it crosses the access track along the edge separating the concrete hardstanding from the gravel track. The boundary then follows the southern side of the track before turning eastwards along the base of the earthwork mound around the settling tank (A14) and at its eastern end around the waste kerosene system (A14.1) and from here westwards along the southern edge of the access track. It then crosses the track and along the western side of the bridge over the effluent conduit to its southern edge. The southern side of the concrete conduit marks the boundary until at the base of test stand A42 it meets the modern post and wire fence. It follows the fence line for a short distance until it meets the northern edge of the lower access track past the remains of the kero dump tank . The boundary continues along the track edge and then turns north along the southern side of a minor track to the north-west corner of the fenced compound. From this point the boundary follows the outer edge of the concrete hardstanding and along its eastern edge returns southwards before heading eastwards towards the north-east corner of the fenced area. At its western end the northern boundary is marked by a modern concrete revetment wall and the outer kerb stones of main access track. To the rear of stand A3 it follows a notional line between the kerb edge as it does to the area between stands A3 and A2, where the original surface is covered by modern asphalt.
03, 04, 05 and 06 Observations Posts: the boundary of each post is defined around the outer edge of their covering mounds.

Exclusions
Any surviving original concrete road surfaces associated with the Spadeadam Cold War rocket establishment are included in the scheduling however, the upper, later road surface of asphalt, all fences and fence posts, signage, light fittings and the static range targets are all excluded from the scheduling, although the ground beneath these features is included.

Source: Historic England

Reasons for Scheduling

The 1957 Engine Test Area is scheduled for the following principal reasons:
* Rarity: as an essential and integral part of a unique British Cold War rocket establishment believed to be the sole survivor of its type in the western world;
* Survival: significant earthwork, buried and standing remains survive at this site including the bases of four engine test stands and an associated control building which illustrate one component of the rocket test facility;
* Potential: it will enhance our detailed understanding of the engine testing operations and their essential contribution to the successful functioning of the rocket establishment, as well as serving as a tangible and evocative symbol of Britain’s aspirations to super power status;
* Historic interest: it will enhance significantly our understanding of the development and operation of Britain’s Cold War independent nuclear deterrent, and the subsequent utility of the technology in the development of international space exploration; the rocket test stands are similar in design to those used by Rocketdyne in the USA and reflect the special relationship between the two countries;
* Group value: as part of a single phase, grand scheme site conceived for a single rocket programme, the relationship of each site to the others and the wider landscape adds group value and enhances the national importance of the whole;
* Period: the peril from the threat of mutually assured nuclear destruction, which characterised the Cold War period is inherent in the remains of the Spadeadam rocket facility in the most tangible and evocative fashion.

Source: Historic England

Sources

Other
Tuck, C & Cocroft W D, Spadeadam Rocket Establishment, Cumbria, 2004,

Source: Historic England