Control Tower, Yorkshire Air Museum (former RAF Elvington)

Control Tower (Watch Office), Yorkshire Air Museum

This control tower was constructed in 1942 to designs by the Air Ministry's Directorate of Works and Buildings, based on drawing 12096/41, as a Night-Fighter Stations Watch Office. It exemplifies the permanent construction standards of the period.

The building is a two-storey rectangular structure aligned roughly east to west, with its main elevation facing west over the runways and rear access to the east. It is built of rendered and painted brick with 34.3 centimetre (13.5 inch) thick walls, pre-cast hollow beam reinforced concrete floors and roof, and galvanized-steel Crittal windows. A reinforced concrete observation gallery with galvanized steel tubular handrail is cantilevered from four I-beam girders across the width of the main elevation, accessed by a roof companionway ladder at the rear.

The main (west) elevation has three rectangular 32-light Crittal casement observation windows with flush rendered plain sills and jambs to each storey. The ground-floor windows light the watch office that spans the building's full width; the first-floor windows light the control room, also spanning the width, each with a centrally set ventilation brick above.

The south elevation contains four square 16-light Crittal casement windows to the ground floor lighting the watch office, duty pilot's rest room, and electrical switch room, plus one narrow eight-light window with projecting sill lighting the pyrotechnic cupboard. The first floor has a large observation window to the left, an adjacent six-light glazed Crittal door accessing the observation gallery, a 12-light window lighting the radio telegraphy room, and a square stair window to the right. Ventilation grilles and bricks serve the duty pilot's rest room, store, and first-floor signals room.

The north elevation is similar, though windows differ in size, shape, and position. A ledged and braced timber door to the left accesses a short transverse corridor; the observation gallery is accessible only from the first-floor control room on this side. Ventilation provision serves ground-floor officers' and airmen's lavatories and the private branch telephone exchange (PBX), and the first-floor controller's rest room.

The rear (east) elevation is largely blank except for the main entrance, offset to the right and closed by a ledged and braced timber door. To the left is a narrow eight-light casement lighting the staircase base. A further door with ventilator panel at its base accesses the electrical switch room. A steeply inclined steel companionway ladder rises to a cantilevered concrete landing providing roof access. All roof sides are guarded by two-bar steel railings and drained by modern plastic rainwater goods.

The ground floor can be entered from the main rear entrance, the north side door, or the electrical switch room (which also functions as a light baffle entry). The interior features concrete floors, painted brick walls with rendered dados, and original joinery including panelled utility doors. The main entrance leads into a stair hall with officers' and airmen's lavatories to the right and a concrete staircase with timber handrail rising to the left. An under-stair store cupboard lies beyond a doorway adjacent to the staircase. The hallway narrows into an axial corridor leading to the watch office at its far end, with the duty pilot's rest room on the left and the PBX room on the right. A single panel door with ventilator from the pilot's rest room allows internal access to the electrical switch room. Beyond the PBX, the axial corridor interconnects with the side door corridor. The watch office is a narrow rectangular room spanning the building's width with a brick pyrotechnic cupboard in the south-east corner. Ground-floor ceilings comprise pre-cast hollow concrete beams resting on longitudinal rolled steel joists (RSJ).

The first floor is accessed by a concrete staircase rising against the east wall, which has a short rendered brick balustrade at its base with a single timber handrail and rendered dados. The staircase is flanked at first floor by a landing with painted brick balustrade wall. The landing leads to an axial corridor accessing the controller's rest room to the right, the signals room to the left, and the control room at the far end. A pyrotechnic locker with steel door stands at the opposite end of the corridor from the control room. The rectangular control room occupies half the first-floor area, with wide observation windows in the main and both side elevations and doors in each side wall accessing the external observation gallery. An internal window with open teleprinter message slot beneath, situated in the rear wall, communicates with the adjacent signals room. First-floor ceilings comprise pre-cast hollow concrete beams resting on substantial RSJ beams: one spans the full width of the control room and one spans the signals room and controller's rest room.