Command Bunker
The command bunker at a Second World War heavy anti-aircraft (HAA) battery followed a remarkably consistent design across the United Kingdom. Typically arranged with six internal rooms, the central space served as the plotting room where firing data was calculated and relayed to the guns, while the two end rooms functioned as officers’ offices. Access arrangements varied slightly between sites: some bunkers, such as those at Kerketh Battery, had steps leading out to the rear of the structure, while others also included steps from the officers’ rooms onto the front platform where the predictor and range finder were positioned. In some cases, steps led down into the bunker from this platform, whereas at Predannack the entrance was formed by a sloped approach. Although small modifications were made to suit local requirements and terrain, the overall footprint and internal arrangement of the command bunker remained largely standardised throughout the country.
1941 Pattern Gun Pit
The 1941 pattern gun pit at a World War II heavy anti-aircraft battery was built to a standard circular design, providing a stable platform for the 3.7-inch anti-aircraft gun. Set back from the main gun platform were a series of supporting rooms built into the surrounding structure. Each gun pit contained seven ammunition magazines, two crew rooms, and two decontamination rooms positioned on either side of the entrance. The crew rooms provided shelter for the gun detachment between engagements and were typically fitted with small wood stoves, allowing the men to keep warm while standing down between air raids. Once the gun had been installed, the entrance passages to the pit were sealed with blast walls, protecting the ammunition stores and crew areas from the effects of nearby explosions while maintaining access around the gun position.
1943 Pattern Gun Pit
The 1943 pattern gun pit at a World War II heavy anti-aircraft battery was a simplified development of the earlier design. Although most were circular, some examples were built in a square arrangement, but a defining feature was that the ammunition magazines projected into the gun pit itself—opposite to the 1941 pattern where they were set back behind the pit wall. These magazines stored the gun’s ammunition on wooden racking and were fitted with metal doors at the front and rear to help protect the contents from weathering. Unlike the earlier design, the 1943 pattern contained no crew rooms, making it quicker to build and requiring fewer materials and less manpower. As with the 1941 pattern, the entrance to the pit was protected by a blast wall, shielding the crew from external explosions and also protecting personnel outside the pit from accidental detonations within—tragically illustrated on 11 August 1944 at Corbyn’s Head in Torquay when a breach explosion during Home Guard training caused a fatal incident.