World War Two Filter Room

Group Filter Room for HQ 13 Group Fighter Command built on site of Blakelaw Quarry (HER 4254). Built after the Battle of Britain because the Filter Room at HQ Fighter Command was becoming swamped by the volume of information being received from radars and other sources. Filter Rooms were sites where information on enemy raids detected by the radars was fed. Conflicting reports on such raids were reconciled in the filter room, and then the filtered information was then passed on to Group HQ Operations Rooms (such as the Kenton Bar Bunker (HER 5035)).and to the principal fighter airfields, known as sector stations. Acting on the instructions of the regional air defence commander at the Group HQ, sector station commanders would dispatch fighters to intercept the approaching enemy. The part played by Group HQ Operations Rooms was of crucial importance, for there all aspects of regional air defence came together, including reports from the Observer Corps and control of Anti Aircraft guns. HQ 13 Group at Kenton Bar, was responsible for air defence of the entire country from Yorkshire to the Shetland Islands. LOCAL LIST