P-18
The P-18 ( Russian П-18 Терек , German P-18 Terek ) is in the Soviet Union developed 2D - radar apparatus . The system introduced into the armament of the Soviet Army in 1971 is used for reconnaissance of air targets and for target assignment. The factory designation is 1РЛ131 (transcription: 1RL131). The NATO reporting name is Spoon Rest D .
The radio technical troops of the NVA designated the radio measuring station with P-18 or for reasons of secrecy with 08 . In the air defense system , the system was also known as Rundblickstation 18 , or RBS-18 for short .
development
The P-18 was developed as a further development of the P-12 . The aim of the development was a deployable radar device with a high range, which was primarily intended for reconnaissance of the airspace and for target allocation for the anti-aircraft missile systems of the air defense. For these long-range missile systems, a high reconnaissance range in a large altitude area was required, while demands for accuracy, resolving power and high tactical mobility took a back seat.
Compared to its predecessor P-12 , the range and interference protection properties should be increased. The P-12 ultimately goes back to the British Light Warning Radar AA No 4 Mark II or Mark III supplied by Great Britain during the Second World War under the Lend-Lease Act . The 30 units delivered were designated as ORL-4 ( OРЛ-4 ) in the Soviet Army . The radar stations Most-2 and P-5, introduced in 1946, were created on this basis . Also introduced in 1946 was the P-3 radar station , which was based on the RUS-2 developed by the Soviets . From the P-3 and the P-5 , the P-8 finally emerged in 1948 and finally the P-10 around 1950 . Finally, between 1954 and 1956, the P-12 was built , which was continuously developed until the early 1970s. All of these radars are pulse radars that operate in the VHF range. The frequency range required a relatively large antenna system, which was designed as a group antenna with individual Yagi antennas. This made construction complicated and tedious, resulting in poor tactical maneuverability. However, since the dimensions of the antenna system could not be chosen arbitrarily large, the accuracy of the angle determination and the resolution of the side and elevation angles were relatively low.
Compared to the P-12 , the number of Yagi elements on the P-18 has been increased from 12 to 16, which resulted in a narrower directional diagram. Particular attention was paid to improving the interference protection options. The experiences of the Vietnam and the Six Day War required an improvement in the tactical and technical properties in this area. With the anti-radar missile AGM-45 Shrike , introduced in 1963, radar stations on the battlefield were exposed to greater danger. At the same time, the rapidly evolving options for actively jamming radar devices increasingly restricted their possible uses. The Soviet designers sought to increase survivability on the battlefield by improving the interference protection systems, but also by using widely spaced wave ranges.
construction
Construction of the radar station
The system consists of
- the equipment vehicle on truck Ural-375D later on Ural-4320
- the aerial vehicle AMU on Ural-375D later on Ural-4320
- two unit trailers PS-1 and PS-2 each with an electrical unit (for the NVA with GAD-16 and in the PS-1 with a switch cabinet for "uninterrupted load transfer" ULÜ-M )
- the identification device NRZ-12 later 1L22 ( 1Л22 )
The components of the system enable largely autonomous use as well as testing, maintenance and repair under field conditions.
Basic interaction of the elements of the weapon system
The antenna system is loaded onto the antenna vehicle. The equipment vehicle accommodates the essential electronic components of the system in the case. The workplaces of the soldiers deployed to operate the system are also located here. Antenna and equipment vehicles as well as the aggregate trailers are wired together after the station is set up. On the aggregate trailer there is an electrical aggregate, spare parts, tools and accessories as well as the cable sets necessary for cabling the station. It takes 50 minutes to set up the system, plus another 3.0 minutes to switch on the system. This time is due to the necessary preheating of the electronic assemblies. A time of 45 minutes is required to establish the marching position, i.e. to dismantle the station.
Recognized air targets are displayed on a panoramic device. The system can also be operated from outside the equipment vehicle. For this purpose, the daughter viewing device is used, which can be deployed at a distance of up to 300 m from the radio measuring station. Contrary to the possibilities of the P-12 , the P-18 can no longer determine the altitude of the air target. To determine the altitude (of the flight destination), this radio measuring station must be coupled with so-called altitude finders such as the PRW-9 or the PRW-16 . The cleared air targets are identified with the help of the integrated identification device. Target data from other radar stations can also be displayed on the P-18's display devices , and target data determined using the P-18 can also be transmitted to other radar stations. For this purpose, the rotations of the antennas and the pulse trains of the transmitters are synchronized via a coupling device ("Schkaf 5").
In order to increase the immunity to interference and the reconnaissance range, the P-18 is usually used together with other radar stations. The P-15 or P-19 and the P-40, which work in the decimeter wave range, are used regularly . In addition: the frequency range used by the P-18 also facilitates the reconnaissance of air targets with stealth properties and: anti-radar missiles are not yet available for this frequency range.
The operation (in the NVA) consists of a total of seven soldiers. This makes it possible to work in shifts, as only four soldiers are required at the same time to operate the station.
Carrier vehicle, cabin and power supply
The all-terrain truck Ural-375D (later Ural-4320 ) is used as the carrier vehicle . The system can be laid on streets as well as in the field. Due to the heavy structure with a high center of gravity and the sensitive electronic assemblies, however, a maximum speed of 10 km / h must not be exceeded in the field.
A length of 8.4 m with a width of 2.7 m and a height (in heading position) of 3.4 m are specified for both the device and the aerial vehicle. The total weight per vehicle is 13 t. The electronic assemblies, the telecommunications equipment and the operator's workplaces are located in the case of the equipment vehicle. The OW-65 heating and ventilation system enables the case to be supplied with heat and ventilated, even when the vehicle is stationary, regardless of the operation of the drive motor. To protect against radioactive, chemically and biologically (bacteriologically) contaminated outside air, later versions of the case are equipped with the FWUA-100 filter ventilation system. To do this, the case is pressurized and the sucked in air is filtered. The system can be operated while the vehicle is in motion and when stationary, but the case must be left to set up and dismantle the radar system.
An independent navigation system is not planned. In order to determine the exact position, the deployment position must be measured using the alignment circle supplied with the aid of known and measured terrain points.
The power consumption of the entire system is around 10 kW. The power supply is provided by the two electrical units installed on the unit trailers, which provide a three-phase AC voltage with a mains frequency of 50 Hz and a voltage of 230 volts (!). Each unit can generate up to 16 kW. In the NVA version, a 4NVD 12.5 SRL diesel engine drives a DCBS-20-4 / Z generator . The station's trailers still contained the spare parts, tools and accessories required for maintenance and field repairs. The cable sets were loaded onto the roof of the trailer. The K.700 trailers are two-axle trailers with stub axle steering . The selected type of steering turned out to be (very) problematic, especially at high cruising speeds.
Antenna system
As with the previous models, a group antenna is used as the antenna , which consists of Yagi antennas arranged in two rows . Compared to its immediate predecessor, the P-12 , the number of Yagi antennas has been increased from 12 to 16, which improves the resolution in the side angle. Each Yagi antenna has a reflector and four directors. The antenna system is mounted on a lattice mast. The antenna mast can be increased up to 11 m by using intermediate segments. During operation, the mast head rotates at 0-10 / min in the horizontal plane; to adapt the directional diagram , the antenna system can be swiveled through an angle of −5 ° to + 15 ° in the vertical plane. Due to the directional characteristics of the antenna, air targets with an altitude of up to 30 km can be detected. However, an altitude display as with the P-12 is no longer provided, as much more accurate altimeters (e.g. PRW-16 ) are used today . The dead funnel had an angle of approx. 42 °. In this area around the vertical axis, aerial targets cannot be identified, or at least only very imprecisely.
The antenna drive consists of a servomotor controlled by a magnetic amplifier and a so-called electromotive amplifier (EMC) . Synchronous rotation with other radar devices is possible via the resolver in the mast head . This synchronous work with external radar devices is also practiced via a coupling device that also synchronized the transmitters, so that a common display of the analog target signs on a PPI panoramic device is possible.
The antenna system determines the accuracy of the determination of the side angle and the resolution . The side angle could be determined with an accuracy of 1.5 °, the resolution was 6-8 °. In practice, this means that all aerial targets that were at approximately the same distance in a sector each 8 ° wide were shown on the viewing devices as one aerial target.
Radar device
The structure of the transmitting and receiving part remained largely unchanged compared to the previous model P-12 . In the transmitter using a cavity resonator with a Scheibentriode type GI-19B as an active component. The approximately 2 m long tube of the pot circle takes up almost the entire right side of the case of the equipment vehicle. The transmitter is tunable, but only four fixed frequencies can be locked in active operation. The transmitter works in the frequency range from 150 to 170 MHz and sends out 6 µs long pulses with a pulse power of 160 to 260 kW. The automatic frequency adjustment adjusts the transmission frequency to the constant reception frequency. To increase protection against certain types of active radio measurement interference , the pulse repetition frequency can be swept in the range from 200 to 360 Hz .
The receiver of the P-12 built with tubes was used again, but here a transistorized HF stage is connected upstream. Due to the increased sensitivity of the receiver and the increase in antenna gain by increasing the number of Yagi elements from 12 to 16, the range of the system has been increased compared to its predecessor. It is a maximum of 360 km and is limited by the installed radar range . As with all radar devices, however, the actual reconnaissance range depends on the effective radar reflecting area , the altitude of the air target and the surrounding terrain. With a nominal power of 80% and a radar reflecting area of 1 m 2 , an air target at a height of 50 m at a distance of 20 km, at an altitude of 30,000 m up to a distance of 250 km. The fact that the station works in the meter wave range has a positive effect on the range. Since electromagnetic waves are more strongly diffracted by the earth's surface in this wave range, the range is increased by 5 to 10% compared to radar devices with similar performance characteristics that work in the dm and cm wave range. Another benefit of using meter waves is the ability to better locate stealth aircraft . The effectiveness of the techniques used to camouflage these aircraft depends on the wavelength of the electromagnetic radiation used to locate them. For example, in the meter wave range, known radar-absorbing materials cannot be applied in the necessary layer thickness; effective shaping is only possible with considerable effort and compromises.
To protect against passive interference and fixed targets, there is a system for selecting moving targets (SBZ) that works with potential storage tubes. The complex wind compensation , which works in the freely adjustable distance range and thus improves the interference protection, is remarkable . This system was also initially adopted unchanged from the P-12. In later modifications, fast field effect transistors were used in the SBZ , so that the P-18 could be completely remote-controlled.
The manufacturer modified the system for selecting moving targets again later. Later versions of the P-18 received a digital SBZ ; however, these modifications were no longer used in the East German NVA. The digital SBZ was also offered for retrofitting. The P-18s used by the Hungarian People's Army also received a fully digitized receiver from local production.
The air situation is shown on the round view device in the box body or on the daughter view device. The situation map is updated depending on the speed of rotation of the antenna, i.e. up to every six seconds.
The main viewing device is installed on the front of the device case. The daughter display device is located on the left side next to the NRZ-12 equipment cabinet. (In later versions, both viewing devices are installed on the left-hand side.) The child viewing device can be operated up to 300 m away, in later versions the station can be controlled completely remotely from the child viewing device.
The result of the identification query is displayed on both display devices. Originally the P-18 was used with the Kremnij-2 system, the corresponding equipment was located in an equipment cabinet on the left side of the box body. With this system only the affiliation of the aircraft to its own forces can be displayed. From 1979 the Parol system was available as a secondary radar device . (However, it was not installed in all existing P-18s.) Compared to the predecessor, in addition to the actual identification ( friend or foe ) and its display on the display devices, the query and display of additional information such as flight number, altitude of the aircraft and the the remaining fuel (in percent) if the aircraft is equipped with the corresponding system ( transponder ). The NRZ-4P (1L22) version is used , which is loaded on an Ural-4320 truck .
Modifications
The P-18 was modernized to the P-18M version from the late 1980s . The P-18-2 (1-RL-131-2) is currently being offered, which, as already described, is characterized by extensive digitization of the receiving section and the display.
commitment
Operational principles
The P-18 was originally intended for use by the forces of the air force and air defense. Here it was and is generally used to clear up the airspace and display the air situation picture. Another area of application is the determination of target data and their transfer to various stationary and deployable anti-aircraft missile systems of the air defense. In this role she largely replaced her predecessors P-8 and P-12 . It was used by the flying units of the air force to bring fighter planes closer to enemy aircraft. The P-18 can be operated remotely from the child display device in the corresponding control point (e.g. the GDFL). [There is also a feed of the vision data (azimuth, distance, echo identification) without the coupling apparatus is "Schkaf 5" in the system WISP-75 (in the LSK / LV of the NVA: WISP-75T) is possible in the GDFL. (In this deployment variant, however, there is only limited remote control capability.)]
Due to the long set-up and dismantling times , the P-18 is not very suitable for use by the mobile air defense units . Nevertheless, it was and is also used here. In particular, the evaluation of the Middle East wars had shown the susceptibility of radar systems to active and passive radar interference and anti-radar missiles . The use of radar stations that work in different wave ranges is advantageous here, since these radar stations cannot be disturbed by the enemy at the same time, or only with great effort. In addition, anti-radar missiles are not available for the meter wave range. Another advantage was the fact that the P-18 can be used to detect air targets in distance and altitude ranges that are not covered by the P-15 or P-19 . In the air defense units and associations, the P-18 was and is generally operated together with the P-15 or its successor, the P-19 . This configuration is supplemented by an altitude finder PRW-9 or PRW-16 , which provides information about the flight altitude. With the use of highly mobile anti-aircraft missile systems such as the 9K33 Osa , which allowed shooting from a short stop, the P-18 no longer met the increased mobility requirements and was again separated from the units of the air defense.
States of operations
The P-18 was introduced into the Soviet Army in 1971. The system was exported to numerous countries and is still partially in use there.
During the NATO air strikes in the Kosovo war on targets in Yugoslavia ( Operation Allied Force ), the 3rd Battalion of the Serbian Missile Brigade 250, equipped with a P-18 radar and SA-3 Goa missile stations, succeeded on March 27 1999 to shoot down an F-117A with the registration number 82-0806. The pilot was able to save himself with the parachute.
Use in the NVA
In the National People's Army of the GDR , the P-18 was used from the 1970s both by the air forces / air defense (LSK / LV) and the air defense troops . At the TLA, the P-18 was called Rundblickstation 18 or, for short, RBS-18 .
Air defense used the P-18 as an aerial reconnaissance and targeting radar for the S-75 Volkhov anti-aircraft missile system . Here she replaced the P-12 in this role.
The radio technical battalions and companies of the LSK / LV also used the P-18 . They were responsible for the uninterrupted reconnaissance of the airspace. Depending on the location and assignment, the radio engineering battalions were assigned a different number of P-18s , but each radio engineering company had at least one and a maximum of four P-18s .
With the introduction of the 2K12 Kub anti-aircraft missile system and the conversion of the anti-aircraft departments of the armored and motorized rifle divisions of the GDR's land forces, the use of the RBS-18 in the air defense began in 1976 . The command batteries of the anti-aircraft missile regiments of the 1st , 4th , 8th and 11th motorized rifle divisions and of the 7th and 9th armored divisions each received an RBS-18 . With the introduction of the 9K33 Osa anti-aircraft missile system, the RBS-18 was separated from the command batteries of the anti - aircraft missile regiments 8 and 11 and replaced there by a second RBS-19 . The radio technology battalions of military districts 3 and 5 also use the RBS-19 . For each battalion, two radio engineering companies each received an RBS-19 .
Whereabouts
In total, the NVA had around fifty P-18 radio measuring stations . According to previous knowledge, the NVA used the 1RL131-1 version, but no knowledge is available about the introduction of modernized variants.
So far the whereabouts of three P-18s could be proven:
1. Swiss Military Museum Full (which is probably the P-18 from the Musée de l'Abri de Hatten (France)),
2. Defense Technical Service 81 (WTD 81) in Greding (stored),
3. Military history museum of the Bundeswehr at Berlin-Gatow airfield (partially on display).
All three stations are stored and displayed together with the 1L22 “Parol” (NATO: “Dog tail”) system.
There is currently no reliable information about the whereabouts of the remaining facilities after the dissolution of the NVA in 1990. It is known, however, that the sensitive parts of the secondary radars of the "Parol" system were handed over to the Soviet Army and returned to the USSR .
Tactical-technical data
| Technical data P-18 "Spoon Rest- D" | |
|---|---|
| Frequency range | 150-170 MHz |
| Pulse repetition time | 2.77 ms |
| Pulse repetition frequency | 360 Hz |
| Transmission time (PW) | 6 µs |
| Reception time | 2.4 ms |
| Dead time | 377 µs |
| Pulse power | 160-260 kW |
| Average performance | up to 540 W |
| displayed distance | up to 360 km |
| Distance resolution | 900 m |
| Opening angle | 6 ° |
| Hit count | > 15 |
| Antenna round trip time | ≥ 6 s (continuously adjustable) |
Individual evidence
- ↑ a b Из истории выпуска РЛС П-18, manufacturer's website (Russian)
- ↑ a b c d e f g h i j k l m n o p q Missile and Weapons Service in Kdo.MB III, technical catalog, Rundblickstation 18 (1RL131-1)
- ↑ a b c d e f g h i j k l m n o p q r s t u Reconnaissance station RBS-18
- ↑ a b c d e f g h i j k l m n o p q r s The pages of the radio technical troops of the NVA, P-18
- ↑ The times specified for the upgrade and disarmament may vary depending on the country of deployment.
- ↑ Missile and Weapons Technical Service in Kdo. MB III, Kremnij identification system
- ↑ Missile and Weapons Technical Service in Kdo. MB III, Parol identification system
- ↑ Модернизация РЛС П-18 всех модификаций (Russian)
- ↑ http://www.airspacemag.com/military-aviation/unconventional-weapon-23371597/?page=5
- ↑ US plane shot down, pilot rescued. CNN, March 27, 1999
- ↑ Stealth Nighthawk downed in Yugoslavia. CNN, March 28, 1999
- ↑ NATO stealth missions continue after crash. CNN, March 28, 1999
- ↑ Cake with ejector seat . In: Der Spiegel . No. 33 , 2007 ( online - 13 August, 2007 ).
