prototype for production, the Army made arrangements for the Rubin to be tried by the Red Fleet Command. At the beginning of 1944, the system was transported to Murmansk, the only non-freezing port in the Soviet Arctic. Here, despite the cold, Usikov continued with tests and demonstrations under better conditions than in the still chaotic Moscow. Tests aboard a ship showed aircraft detection at 60 km and reliable measurement starting at 40 km. The mean errors were no more than 120-m in range and 0.8-degrees in azimuth and elevation angles. The time for determining the angular coordinates never exceeded 7 seconds, and the dead zone was down to 500 m. Similar accuracies were found for detecting all types of surface vessels, but with the Rubin antenna at deck level, the detection range was understandably much less than that for aircraft. During the last year of the war, Rubin was used by the Red Fleet for air and surface surveillance in the polar sector. If the GL Mk II and its clone, SON-2ot, had not become available, the Rubin would likely have been completed much earlier and gone into production. Although never put into regular service, this system provided a good foundation for future magnetron-based radars in the Soviet Union. The cold war brought the threat of intercontinental supersonic bombers. This led to the development of integrated air defense systems such as Uragan-1 where search and acquisition radars at great distance from strategic areas detect inbound threats, integrate that data into an attack or intercept solution, then engage the target with interceptor aircraft or anti-aircraft artillery as the intruder progresses into several layers of weapon systems. Airborne A number of new fighter and bomber aircraft were being designed in the years before the war. Vladimir Petlyakov led a Soviet Air Forces (VVS) design bureau, responsible for developing a twin-engine attack-dive bomber that was eventually designated Pe-2. Having fallen behind the schedule, Petlyakov was charged with sabotage and thrown into a technical Gulag; he actually did a large part of his design while incarcerated. In late 1940, the VVS developed the requirement for an on-board enemy aircraft detection system. The radio-location group at NII-9 in Leningrad was directed to design such a set for the Pe-2. Most of radio-location equipment at that time was large and heavy, and for this aircraft, a small, lightweight set was needed. Also, limitations on antenna size