ANTI AIRCRAFT DEFENCE SITE

SN Sites, buildings and structures for the control and mounting of anti aircraft artillery. Also, structures for passive or indirect defence against enemy aircraft.
CL MILITARY DEFENCE AND FORTIFICATION
BT ACTIVE AIR DEFENCE SITE
NT ANTI AIRCRAFT BATTERY
ANTI AIRCRAFT GUN TOWER
ANTI AIRCRAFT OPERATIONS ROOM
BARRAGE BALLOON SITE
SEARCHLIGHT BATTERY