Site Records

SiteName: Isle of Man Radar Stations - Bride CH

The three CH stations on the Isle of Man were very similar. The main differences were that Bride and Dalby each had two Type C transmitter blocks and two Type C receiver blocks, whereas Scarlett had one pair of Type C transmitter and receiver blocks and one pair of the earlier Type B transmitter and receiver blocks. This indicates that planning for Scarlett started earlier than for the other two chain home stations. The Type B blocks were designed to accommodate two sets of equipment in a larger brick building with a concrete roof surrounded by a separate concrete blast wall. Before many of these buildings had been built, it was realised that it would be more sensible to disperse the equipment and therefore later stations had the two pairs of Type C buildings, each with one set of equipment. The few stations with the Type B blocks were therefore provided with an additional Type C receiver block and a Type C transmitter block.

The Chain Home radar station at Bride was established on farmland to the southwest of the Point of Ayre Lighthouse in 1941. This station was also known as A.M.E.S. No. 62.

In 1944 Bride and the aerials, masts and towers were dismantled and removed soon after the end of the war but some concrete bases and stubs remain in the ground. The equipment was removed. Most of the technical blocks and some associated artefacts are still intact, although many of the brick buildings (e.g. accommodation blocks and cookhouse for the guards) have been demolished. Some of smaller steel and concrete components of the transmitting aerial systems have been dug up, presumably to increase the usable area of the fields, and moved to another area or placed at the field boundary. Some of these concrete blocks have been used to prevent access to technical blocks.

Nineteen sites that formed part of Bride have been identified. At present only one receiver block and one set of receiving aerial stubs are to be seen on the ground. Duplicate sets of receiver blocks and receiving aerials were planned for Bride. Aerial photographs were therefore studied to locate the missing structures. In these photographs, a receiver block and a receiving aerial tower are clearly visible in the field immediately to the north of the intact receiver block and set of receiving aerial tower stubs.

The northern receiver block was buried, probably during recent landfill operations, but the two southern corners of the concrete roof are still visible and the length of the building matches that of the intact southern receiver block. At the present time, there are no signs of the northern receiving aerial tower stubs.

The stubs and cable junction box of the northern receiving aerial tower appear to have been destroyed and/or buried at the time this field was used by the Government as a landfill site.

The remaining receiver block is in good condition, but access is difficult because the entrances had been closed by blocks of concrete, probably from another part of the station.

Plan of Type C Receiver Block A - goods entrance, B - earth bank, C - transformer room D - switchgear and ventilation system connected to ducting throughout building, E - pump, F - filter unit, G - roof vent, H - electrical part store, I - receiver equipment, J - electro-mechanical calculator, K and L - cable ducts, M - battery room (GPO), N - personnel entrance.

The receiver block housed receiving equipment which presented a display to the operator, usually WAAF, on a CRT. The distance between the start of the trace and the vertical blip indicated the distance of the target from the station. The magnitude of the blip indicated the number of aircraft (raid strength). The bearing of the target was determined by comparing the signals received by two dipole aerials (N-S and E-W) mounted horizontally at right angles in the receiving aerial mast. The comparison was made by adjusting the calibrated knob of a goniometer to minimise the height of the echo on the CRT. The goniometer had two stator coils at right angles, each of which was fed with the signal from the corresponding dipole aerial, and a search coil was connected to the calibrated knob.

These stator coils recreated in the goniometer the radio field that prevailed at the receiving aerials. The bearing of the target was determined by rotating the search coil for a maximum signal on the CRT (in practice operators found that more precision was obtained by searching for a minimum signal and correcting by 90 degrees).

Two receiving aerial systems were used to determine the angle of elevation. One system was designed to give maximum signal at a high angle of elevation and the other was designed to give maximum signal at a low angle of elevation. By comparing the two signals and taking account of the curvature of the earth it was possible to calculate the elevation of the target aircraft [28]. In order to take account of the local terrain, height curves were plotted from aircraft making calibration flights and these were used to convert elevation to altitude.

Receiving aerials at Bride on 31st July 1942

Soon the calculation of altitude was made automatically by racks of electromechanical equipment (Figure 16) which also stored the calibration data. This equipment was designed by the Post Office Research Station at Dollis Hill. Relays and uniselectors in the calculator allowed the grid reference and the raid strength of the target to be stored.

It is not possible to identify the original locations of all these pieces of equipment because at the time of writing no drawings or photographs have been located which show the equipment in use in a Type C receiver block.

The receiving aerial towers were constructed from wood and each of the four legs was bolted to galvanised steel stubs set in massive concrete block foundations. All that now remains on the site are the receiving aerial cable junction box and the four steel stubs for the wooden legs of the tower.

Further information and pictures about this site continues here

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