In the Soviet Union, the Gneiss-2 radar went into serial production during the Great Patriotic War, this happened in 1942. This aviation radar was installed on the following aircraft models: the Pe-2 two-seater dive bomber, the Pe-3 heavy twin-engine fighter, as well as the Douglas A-20 bombers, which were supplied to the USSR from the United States under the Lend-Lease program. In total, more than 230 stations of this type were assembled in the Soviet Union.
In 1932, orders for the development of aircraft detection equipment were transferred from the Military-Technical Directorate of the Red Army to the Main Artillery Directorate (GAU) of the People's Commissariat of Defense. GAU, with the consent of the Main Directorate of the Electric Low Voltage Industry, instructed the Central Radio Laboratory in Leningrad to organize experiments to test the possibility of using reflected radio waves to detect air targets. An agreement between them was concluded in 1933, and already on January 3, 1934, in practice, the aircraft was detected using a radar that worked in a continuous mode of radiation. Although the aircraft was found only at a distance of 600-700 meters, the very fact of detection was a success and contributed to the solution of a further defense task. The experiment carried out in 1934 is considered to be the birthday of Russian radar.
By 1939, a scientific and experimental base was created at the Leningrad Physics and Technology Institute (LPTI), which dealt with radio waves. At the same time, under the leadership of Yu. B. Kobzarev (in the future academician), a mock-up of the impulse radar "Redut" was created, in the future the first serial Soviet radar. The creation of this radar station was a significant step forward, since it made it possible not only to detect air targets at long range and at almost all possible altitudes, but also to continuously determine the azimuth, flight speed of targets and their range. Moreover, with circular synchronous rotation of both antennas of this station, it could detect single aircraft and groups of aircraft that were in the air at different distances and different azimuths within its coverage area, tracking their movements with interruptions in time (one antenna rotation).
Thanks to several such radars, which were put into service under the designation "RUS-2" (aircraft radio detector), the air defense command could monitor the dynamics of the air situation in an area with a radius of up to 150 kilometers (accuracy at a range of 1.5 kilometers), timely determining the forces enemy in the air and predicting their intentions. For scientific and technical contribution to the development of the first domestic early warning radar, which was put into mass production in 1941, Yu. B. Kobzarev, P. A. Pogorelko and N. Ya. Chernetsov were awarded the Stalin Prize in 1941.
Early warning radar "RUS-2"
It is quite natural that along with the creation of the first stationary long-range radars, work was carried out in the USSR to create radars that could be installed on warships and aircraft. The development of the first Soviet aircraft radar, designated "Gneiss-2", was carried out already in evacuation. Work on the creation of an airborne radar was headed by Viktor Vasilyevich Tikhomirov, who came to work at NII-20 (today it is the All-Russian Research Institute of Radio Engineering) in 1939. Having graduated with honors from the institute, he quickly joined the team of this defense enterprise and took part in the adjustment and delivery of the first domestic long-range radar, which was put into service in 1940 under the designation "RUS-2".
It is worth noting that, according to the estimates of the Research Institute of the Radio Industry, which were carried out in 1940, the aviation radar, created on the basis of the technologies of its time, together with cables and power supplies, should have weighed no less than 500 kg. Placing such equipment on board the existing Soviet single-seat fighters was not possible. Moreover, the operation of such a radar required continuous maintenance (at the level of development of radio engineering in those years, there could be no talk of automating the process), which would distract the pilot from the piloting process itself. The way out of this situation was the installation of an aviation radar station on a multi-seat aircraft. Here, Soviet engineers did not reinvent the wheel; their British colleagues came to the same decision earlier. At the suggestion of the test pilot of the Air Force Research Institute S. P. Suprun, the Pe-2 dive bomber could act as the carrier of the first Soviet radar, which the Soviet industry switched to serial production at the end of 1940.
At the beginning of 1941, a working model of an onboard radar was assembled at the Research Institute of the Radio Industry, the station was designated "Gneiss-1". The first domestic aviation radar, quite naturally, turned out to be imperfect and incomplete. In addition, during the experiments and tests, the entire stock of oscillator lamps-klystrons of the centimeter range, which were the heart of the onboard radar, was used up, and there was simply nowhere to order the production of new lamps. The outbreak of the Great Patriotic War forced many Soviet industrial enterprises, including the electrical and radio industries, to evacuate to the east. Among the evacuees was the developer of klystrons - NII-9. The specialists and equipment of this research institute were scattered across various factories, and the institute itself actually ceased to exist. The Radio Industry Research Institute was also evacuated, and the necessary testing and laboratory facilities had to be rebuilt at a new location in Sverdlovsk.
The evacuation of NII-20 to Barnaul began in July 1941. In a new location, almost from scratch in very difficult conditions with a catastrophic shortage of necessary instruments and trained personnel under the leadership of Tikhomirov, the first domestic aviation radar station was created, which received the designation "Gneiss-2". In just a few months, it was possible to complete tests of prototypes of the station, which were recognized as successful, after which the first on-board radars went to the front.
A set of equipment for the onboard radar "Gneiss-2"
The pace of work on the creation of the first Soviet aviation radar station can be judged by the following facts. The equipment was manufactured without waiting for the complete release of the documentation. The installation of the radar was carried out according to the basic scheme of work and sketch sketches, getting rid of the arising defects and making changes on the fly. As a result of the efforts made, the first "flight" model of the Gneiss-2 radar was ready by the end of 1941. The radiation power of the station was 10 kW, it operated with a wavelength of 1.5 meters.
In January 1942, at the airfield near Sverdlovsk, the Gneiss-2 radar was installed on the Pe-2 bomber. Testing of the station began shortly thereafter. It is worth noting that the controls and indicator of the onboard radar "Gneiss-2" were located in the operator's cabin of the radar (this place was previously occupied by the navigator), and some of the radar units were installed in the cockpit of the radio operator. As a result of such changes, the aircraft turned into a two-seater, which somewhat reduced the combat capabilities of the vehicle. In parallel with the assessment of the performance of the new radar, which at that time was still experimental, there was a process of working out tactics and methods of combat use of aircraft equipped with a radar station. The main role for such an aircraft was that of a night fighter.
VV Tikhomirov personally headed the construction of the station, ES Stein worked on this project on behalf of the Air Force. When testing the station, the Soviet SB bomber was used as a target. The adjustment and debugging of the radar equipment was carried out around the clock, the engineers worked right at the airfield. The process of checking antennas of various types took place, equipment failures were eliminated, and changes were made to the station design. In the course of the work, it was possible to reduce the "dead zone" of the radar to 300 meters, and subsequently to 100 meters, as well as to improve the reliability of its operation. At the same time, the staff and management of NII-20 understood the importance of creating such a radar. The labor enthusiasm of engineers and ordinary workers allowed, in the difficult days of the war, even before the completion of field tests, to release the first series of 15 Gneiss-2 radars for equipping Pe-2 and Pe-3 combat aircraft. The first combat use of aircraft equipped with a domestic radar took place at the end of 1942 near Moscow.
Pe-2 with radar "Gneiss-2"
In July 1942, the Gneiss-2 station was able to successfully pass state tests. The pace of development and commissioning of such a complex product in wartime conditions was impressive. In January 1942, the first airborne radar was installed on the Pe-2, and the process of its testing began. Already at the end of 1942, aircraft equipped with the Gneiss-2 radar took part in combat missions near Moscow, and then took part in the Battle of Stalingrad. On June 16, 1943, the station was officially adopted by the Soviet Air Force. In 1946, Tikhomirov received the second Stalin Prize for the development of the Gneiss-2 aviation radar.
During the state tests completed in July 1942, the following results were obtained:
- detection range of air targets such as bomber - 3500 meters;
- targeting accuracy in angular coordinates ± 5 degrees;
- the minimum flight altitude when searching for an enemy is 2000 meters (the minimum altitude at which the problems associated with the reflection of radio waves from the earth's surface disappeared).
At the end of 1942, during the most intense time of the Battle of Stalingrad, Tikhomirov, together with a group of developers, departed for the scene of hostilities. Here, engineers were engaged in the installation and adjustment of radar on Pe-2 bombers. Tikhomirov himself often flew as an operator of the Gneiss-2 radar and personally instructed the pilots. The planes equipped with Tikhomirov were used by the Soviet command to block the "air bridge" that the Luftwaffe tried to provide for supplying various cargo to the Paulus grouping surrounded at Stalingrad. Thus, the first Soviet airborne radar aircraft contributed to the defeat of the Nazis on the banks of the Volga. Acceptance tests of Pe-2 aircraft with the Gneiss-2 radar took place already in 1943, they took place near Leningrad.
In the period from February to May 1943, aircraft equipped with the Gneiss-2 radar were used in the air defense system of Leningrad. They were part of the 24th Guards Fighter Aviation Regiment of the Second Air Defense Corps. When intercepting air targets, night fighters were guided to the target using the ground-based early warning radar RUS-2, and when approaching enemy aircraft, they used their onboard radars. Having detected an air target, the operator of the onboard radar "Gneiss-2" transmitted the necessary instructions to the pilot for rapprochement with the target.
A-20G with radar "Gneiss-2"
In 1943, an improved version of the radar was created in the USSR, which received the designation "Gneiss-2M". At this station, new antennas were used, which made it possible to detect not only air targets, but also enemy surface ships. In the fall of 1943, such a station was tested in the Caspian Sea, after which it was put into service and put into mass production. In total, by the end of 1944, more than 230 onboard radars "Gneiss-2" were created at NII-20.
From February to June 1943, the Gneiss-2 radar was tested with the American A-20 bomber; the possibility of using it as a night fighter was considered. Compared to the Pe-2 bomber, the aircraft supplied under Lend-Lease had a number of advantages, therefore, already in July 1943, the creation of the 56th aviation division of long-range fighters began. The division consisted of two regiments (45th and 173rd), armed with A-20 aircraft. Each regiment according to the state was supposed to have 32 aircraft and 39 crews, in addition to this, the regiment included a radar company, which was equipped with an early warning radar RUS-2. This division was subordinate to Long-Range Aviation (ADD). From May 1944, the regiments of the division arrived at the front and were used to provide protection for major transport hubs. In addition to fighting enemy aircraft, aircraft equipped with Gneiss-2 were also used in mine and torpedo aviation regiments to detect enemy surface ships.
In addition to the on-board radars "Gneiss-2" and "Gneiss-2M" of our own production, during the war years, American radars were also installed on Soviet aircraft. In total, the United States sent its allies more than 54 thousand airborne radars, mainly for the UK. In the USSR, 370 radar stations of two types were delivered: 320 - SCR-695 and 50 - SCR-718. After the end of the Great Patriotic War, in the second half of 1945, the Gneiss-5 aircraft radar was put into service in the USSR and put into mass production. As a result of state tests, this radar demonstrated a detection range of air targets of 7 kilometers (with a target flight altitude of 8000 meters).
