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K1 Test Stand, Control Room and Ancillary Building, Former Royal Ordnance Establishment, Westcott, Aylesbury Vale

Description: K1 Test Stand, Control Room and Ancillary Building, Former Royal Ordnance Establishment, Westcott

Grade: II
Date Listed: 23 May 2013
Building ID: 1403968

OS Grid Reference: SP7044816926
OS Grid Coordinates: 470470, 216885
Latitude/Longitude: 51.8461, -0.9784

Locality: Aylesbury Vale
Local Authority: Aylesbury Vale District Council
County: Buckinghamshire
Postcode: HP18 0XB

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Listing Text


Test-stand for solid propellant rocket motors, designed in 1967-8 and completed c1968. Also the K site control room, designed 1959, and a store/workshop building.

Reason for Listing

K1 test-stand at K site of the former Royal Ordnance Establishment, Westcott, a vertical test-stand for solid propellant rocket-motors completed in 1968, and two ancillary buildings (the K-site control building of 1959 and a later store/workshop), are listed at Grade II for the following principal reasons:
* Rarity: a nationally unique test stand for the testing of large solid fuel rocket motors which has contributed to significant UK defence systems and the space programme;
* Fabric and scale: one of the largest solid fuel test stands nationally (with K2) which is impressive in its monumental architecture;
* Intactness: an intact test stand of 1968 which continued in use until at least the mid-1990s: a testament to the success of its original design
* Technological interest: architecture which eloquently expresses the function of the structure; a pioneering test-stand which has tested components for many of the UK's solid propellant rockets/missiles and was therefore at the forefront of this technology nationally. The two ancillary buildings allow an understanding of how the K site functioned as a whole;
* Group value: with the K2 stand and ancillary buildings which formed the K site, the most significant solids test-site at Westcott. Also group value with other test stands at Westcott (such as A-B site) which although for liquid propellant testing are part of the overall programme of seminal propellant research and development which took place at Westcott from the 1940s to the present day.


Westcott has been synonymous with rocket research and development since the mid 1940s. The Second World War saw this work take on a new urgency given Germany’s success in developing the devastating V1 and V2 rockets. After the cessation of hostilities, the importance of German rocket research was fully realised and incorporated into British programmes. The Guided Projectile Establishment opened at Westcott in 1946 and, until 1948, German scientists, classed as special internees, were relocated there to continue their research into liquid propellants alongside their British counterparts. Early research concentrated on liquid bipropellants for rocket engines (using liquid oxygen, hydrogen peroxide and nitric acid oxidisers) with solid propellant research beginning in 1949 (using solid fuels such as extruded cordite and plastic propellants).

In the early post-war years and renamed the Rocket Propulsion Department of the Royal Aircraft Establishment (RAE), Westcott continued research into liquid propellants alongside the Waltham Abbey experimental station. In the early 1950s all work connected with this programme was transferred to Westcott as the large remote site with its specialised and purpose-built facilities allowed rockets to be tested and fired, although not launched.

In the late 1950s the liquid propellant motor for the Blue Streak missile (the RZ2) was developed at Westcott and went on to be used in the Europa-1 space rocket launch vehicle. Naming most of their rocket motors after birds the scientists at Westcott developed many successful engines which were used variously in upper atmosphere research programmes (the Raven) and for the Black Knight research rocket testing re-entry into the earth’s atmosphere (the Cuckoo). Smaller missile programmes were designed and built in Westcott between the 1960s and 1980s including Blowpipe and Seawolf. Large missile programmes, such as Polaris in the 1960s and Chevaline in the early 1970s, were also developed there and are perhaps more widely known. In 1977 Westcott and the Waltham Abbey research station were merged to form the Propellants, Explosives and Rocket Motor Establishment.

Westcott remains at the forefront of liquid propellant rocket motor research and development with, for example, its LEROS liquid engine used in the Mars missions of the late 1990s.


The K test stands are the largest examples at Westcott. K1 is usually described as having been built in 1958 although historical evidence indicates that the late 1960s is more likely. It clearly post-dates an aerial photograph of August 1961 on which its sister stand K2 is shown but not K1. (Despite the numbering, K2 is the earlier of the two stands at K site). Design drawings and plans for K1 in the Westcott archives date to December 1967 (indicating that the job engineer was A H Pengilly) and March 1968. The name of the designer for K1 is not known. Francis Walley, a civil engineer and leading expert in pre-stressed concrete construction (who was involved in a number of research establishment programmes for the Ministry of Works including the design of test stands at Spadeadam, Cumbria) was certainly involved in building some solids test stands at Westcott but these may have been earlier stands, such as the fairly rudimentary early 1950s example in Area 7 or the mid to late 1950s L-site.

K1 was built to allow solid fuel rockets to be test-fired in an inverted position, thus measuring thrust, and was in use until the late 1980s. It is understood to have been operational on a more limited basis than K2. Nonetheless, K1 contributed to many of Britain's rocket and guided missile programmes and continued in use until relatively recently (by Roxel UK). It has been suggested that K1 was large enough to test both the Skybolt (US) and Polaris (UK) missiles from 1960 and 1962 respectively. While the site was sized to accommodate Polaris stage 1 motors, i.e. up to a 54 inch diameter motor, neither were actually tested here but it was used for the Stonechat and Phoenix motors, the latter part of the Blue Water 2 missile programme. Anecdotal evidence from former employees (although individuals who did not actually work at K-site) suggests that Smokey Joe, the main sustainer for the Army's Thunderbird surface to air missile, was tested at K1 or Area 6 but it has not been possible to verify this.

Both K test-stands were operated from a control building (Building 397) to the south-west of K2 which was joined to the stands by raised cable conduits (now demolished). Building 397 was designed in May 1959 and is visible on an aerial photograph of August 1961 providing a terminus ante quem for its construction. Between the control room and the K2 stand is a further store/workshop building (Building 428) supporting both stands. This is later in date, built at some time after August 1961 and is presumed to be contemporary with the construction of K1.


MATERIALS: reinforced concrete, brick.

TEST STAND: K1 is located in the northern test area at Westcott, at the western end of the former south-west to north-east runway (at SP 70471 16885) and approximately 45m south of the K2 test-stand.

K1 is a vertical test stand. It takes the form of a massive reinforced concrete tower which is chamfered towards the apex and which is of broadly rectangular plan. 'K1' is painted in white on a black ground on its north-west elevation. It has a metal platform projecting to the north-east of its flat roof, reached by an external metal stair on its south-east elevation. There are a number of entrances including a pedestrian entrance with protecting concrete porch to the north. Also, to the south-west, is a low motor entrance with a solid metal door. This is again protected by a concrete porch-like projection, with two pairs of rails set in the ground which would have allowed the movement of the rocket motor into the testing chamber. Internally the structure takes the form of a large chimney, sealed at the roof by metal plates. The internal firing bay is reinforced with armour plating and has platforms to allow access to the motor. There are also chains and pulleys suspended from a gantry on the ceiling to assist in the manoeuvring of the rocket motor.

CONTROL ROOM: both K stands were operated from a control building (Building 397) to the west of the test stands. This is a single-storey, L-shaped, flat-roofed brick building, now in use as an office, to which the stands were joined by raised cable conduits (now demolished).

ANCILLARY BUILDING: between the control room and the K2 stand is a further brick, single-storey building (Building 428). It is in two parts, with one half of lesser height than the other; both with large double doors in the south elevation. There is a rocket weather vane on the roof. Its original function as part of the K complex is not known but it is presumed to have been an equipment store or workshop for the calibration of instruments, or indeed both.

The control room and Building 428 are included for group value and have not been inspected internally.

Listed building text is © Crown Copyright. Reproduced under licence.