A - B test-stands and support structures, former Royal Ordnance Establishment, Westcott

A-B Test Stands and Support Structures, Former Royal Ordnance Establishment, Westcott

The A-B site comprises a pair of test stands with protective earth traverses to their north and contemporary fuel management systems. B stand is positioned to the west and A stand to the east. To the south of both stands is Building 276, a contemporary support workshop protected by its own traverse to the north. Building 432 lies between the stands, Building 253 is to the south-west of B stand, and other surviving buildings are grouped in the south-west corner of the site. The structures are constructed in reinforced concrete and brick with earth traverses.

A Test Stand

A stand, also known as Building 251, was originally the pair of D stand at Westcott. It comprises two mirror-image firing bays to the north, each with its own control and observation room positioned to the south-west and south-east respectively. Physical gaps separate each control room from its corresponding firing bay, a modification made after November 1947. Periscopes allow observation of tests, installed after the original steel windows were removed, also a post-November 1947 change. External pipes supply fresh air to the control rooms, and a bath tub stands at the north-east corner of the stand. More recent additions include electrical and ducting fittings, though original features such as a ceiling gantry for lifting motors into position remain. Oxidant is stored to the sides and fuel to the rear. Around 1970, a large liquid hydrogen tank was added to the far west of the stand. An earth traverse protects the north side, with drainage runs and settling tanks positioned to the north and south.

B Test Stand

B stand, also known as Building 250, is smaller and simpler in design and layout than A stand. Originally the pair of C stand at Westcott, it has paired firing bays to the north with related control and observation rooms. The stand retains its original steel windows and thus survives in more original form than A stand, although the reinforced concrete armour-plated observation rooms were modified and strengthened after November 1947. The pipework has been replaced and now reflects its Chevaline testing incarnation in form. Fuel and oxidant tank chambers are located at the rear to the south. An earth traverse protects the north side, with drainage runs and settling tanks positioned to the north and south.

Ancillary Buildings

Building 276, a prefabricated structure of modular panel construction on a 6-foot frame with pitched roof and metal casements, is located south of the stands and protected by a traverse—a feature unique in the protection of a workshop at this stand. It is in somewhat dilapidated condition. Building 253, a further support workshop to the south-west of B stand, is also prefabricated and modular with a pitched corrugated roof and some original multi-paned metal casements.

Building 432 is an L-shaped flat-roofed support workshop constructed in red brick laid in English bond, located between the two test stands. To its south are the concrete footings for the 1/60th Blue Streak Model Silo construction and testing.