is a very difficult task to automate because the aircraft appear only for moments, have high crossing speeds, and are often close to the ground so clutter is a significant issue. Number 6 was designed to make a rapid line-of-sight range measurement while pointing the gun was handled manually as before. There were three entries, Mark 1 through 3, differing primarily in detail. Number 7 AA Number 7 was part of a combined Fire Control System (FCS) for the Bofors guns. It included a rapidly scanning tactical control radar and a separate gun laying radar in a second cabin. The operator of the scanner would select targets, causing the gun laying cabin to slew onto the right bearing. The operator would then find the target, and begin a lock-follow. From then the data from the radar was sent into a predictor in the same cabin as the gun laying radar, which in turn controlled motorized systems on the guns. There were three entries, differing in detail. References Gun laying radars Military radars of the United Kingdom Military equipment introduced from 1940 to 1944