During the Soviet-Finnish War, the chief of the Air Force Research and Testing Institute, General S. A. Danilin, having gained experience of the ground-based Redoubt Radar Redox (RUS-2) under combat conditions, proposed developing an airborne radar system for detecting and attacking enemy aircraft regardless of visibility conditions.
Scientists and engineers at the Leningrad Institute of Radio Industries confirmed the possibility of creating such a system, and under the leadership of A.
The aircraft chosen to install the system was at the suggestion of the test pilot of the Air Force Research Institute, S. Suprun, in which the radar operator could also be accommodated.
A. Fin and V. V. Tikhomirov, the Gneiss-2 radar was created, operating at a wavelength of 1.5 m.[2] The radar was installed on a Pe-2 aircraft and in July 1942 test flights showed the possibility of detecting a bomber-type aircraft at a distance of 300 to 3500 m with an accuracy of ± 5 ° in angular coordinates with a flight altitude of at least 2000 m. The radio research institute completed a pilot batch of 15 stations that were sent to the troops for testing.
In February-May 1943, under the Leningrad 2nd Guards Air Defense Corps, official military tests were conducted (the chairman of the commission, Major General of Aviation Ye.
During the interception, the fighters were guided to the target using the RUS-2 long-range radar, and with the approach to the air enemy, the airborne Gneiss-2 was ready to be used.
Having discovered the enemy aircraft, the on-board radar operator gave the pilot instructions on how to approach the target.