Chronicles: Listening to the Enemy 1 – Ventnor’s Y Station

Most people who live in Ventnor know about the WW2 radar station on top of St Boniface Down, which anchored the western end of the original Chain Home early warning system and was the reason for the heavy German bombing raids that damaged many parts of the town.

What fewer people know is that Ventnor was home to part of another, even more secret system that was critical to the Allied victory. It was the site – the only one on the island — of one of the twenty or so Royal Navy ‘Y stations’ (from ‘WI’ for Wireless Interception) that intercepted and located enemy transmissions and passed the information on to Portsmouth HQ and Bletchley Park (‘Station X’) for decoding. If the radar stations were the ‘eyes’ of the war effort, the Y stations were the ‘ears’.

The headquarters of the Ventnor Y Station was ‘The Heights’ on Whitwell Road, a large private house (later a hotel, demolished in 1989 and now the site of the Foxhills estate), with additional accommodation at a nearby house called Chilonga. Manned by Wrens from the WRNS Special Duties (SD) Service, it mostly intercepted messages in the German Naval Enigma code, which was broken by Bletchley Park. Reading these messages was critical for winning the Battle of the Atlantic against the U-boats.

Other messages, in a simpler, more easily broken code, were sent by local naval facilities, harbour masters and lighthouses on the French coast and in the Channel Islands. By knowing which lighthouses were to be turned on and when, the Royal Navy could deduce if German E-boats were planning a sortie or the movements of coastal convoys. The failure to pick up any such messages on the night before D-Day in 1944 was an important sign that the invasion had achieved the necessary surprise.

As important as intercepting the messages was, knowing where they came from was equally valuable. Some Y Stations, such as Ventnor, had DF (Direction Finding) facilities, usually a 30-foot wooden tower on a concrete base, incorporating a hut with a swivelling antenna. If two or more stations could get a bearing on an enemy transmissions, the sending ship could be precisely located. A skilled operator could pin down the bearing in as little as six seconds.

The Ventnor tower stood on Rew Down, above the Heights (see below for a photograph taken recently). Such towers had to be a few hundred yards from the main receiving station to avoid interference. Most such towers were manned by a single person, and it could be quite scary at night under strict blackout conditions. At Ventnor, the operator had to sit with her back to the door, which could be even more nerve-wracking.

On 15 July 1944 the tower was damaged by a V1 ‘doodlebug’ flying bomb, which also blew out windows of several houses along Whitwell Road. A large crater about 100 feet from the site of the tower is still visible. The Y station wasn’t the target – V1s were accurate only to  within a few miles at best. The six buzz bombs that exploded on the Island during the course of the war were all probably aimed at Portsmouth or Southampton! It was sheer bad luck that this one hit where it did, so close to the DF tower.

The tower was repaired, but the Ventnor Y station ceased operation by September 1944, presumably because Allies now controlled the parts of France and the Channel it monitored. The tower remained standing until 1948 or 1949, but all that now remains is an octagonal brick ‘pillbox’ just below the V54 bridle path, with a concrete foundation and external concrete pads for the wooden supports. Its nature was a mystery until quite recently: some people did remember the tower, but thought it was a transmitter, part of the radar station, or an observation post. Most investigators weren’t even aware the tower had been there, and thought the brick structure was likely to have been an anti-aircraft gun emplacement or the housing for a generator for a searchlight.

A few years ago, members of the Isle of Wight Industrial Archaeology Society began an investigation of the structure, identifying it as a DF tower. Their findings were instrumental in the Grade II listing of the site by English Heritage in October last year. It is one of the best preserved Y station towers nationally and possibly only one of two that retain their brick blast wall.

Next week: Listening to the Enemy 2: The Wrens’ War in Ventnor

Jeff Mazo, Ventnor & District Local History Society. Main sources: Historic England, Remains of a Direction Finding (D/F) tower, Ventnor Y-Station List entry number 1427450, 26 October 2015; Gwendoline Page, ed., They Listened in Secret (2003).