Soviet Night Fighting Tactics And Technology

    

This article is WIP and is subject to revisions as I continue my research. Errors are inevitable as result of translation related complications.

    The Theoretical Framework Of Soviet Night Fighting Tactics:

    The foundation of Soviet night fighting tactics (similar to previously discussed concepts) center around predetermined "rules" for success. These include efficient light support, effective application of artillery/air attacks (fire support), sudden + decisive action, the use of varying "night conditions" to improve the actualization of surprise/stealthy maneuver, continuous cooperation between sub-units throughout the duration of the offensive, and increased tactical flexibility. These norms were defined as a result of studies involving both international and domestic experience, which demonstrated the advantages of engagements at night against an unprepared defensive force. Generally speaking units were capable of accomplishing their objectives with fewer losses when compared to similar endeavors at day, and could defeat significantly stronger enemy forces that would otherwise be impossible to reliably defeat. For this reason, night conditions were to be exploited to achieve the destruction of defensive forces, units advancing to conduct a counter offensive, or retreating formations (in a pursuit).

    It is believed that under the most favorable conditions, the offensive should transpire at nightfall, this allows for darkness to be exploited for the longest period of time, alongside the fact that preparatory action such as reconnaissance and coordination can transpire with some light remaining as opposed to total darkness. Though it must be noted an offensive in the second half of the night (shortly before dawn) is considered equally as advantageous, as the vigilance of the defending force will be decreased and success can be exploited into the day. Normally these attacks would be conducted on the move, without pauses or breaks in the advance, this is done to maintain momentum and avoid the enemy preparing their defenses for a potential assault, withdrawing to occupy a secondary location or moving up reserves to reinforce the position. Conducting night offensives on the move has a number of secondary advantages, such as improving the potential for surprise, it is difficult to pinpoint where exactly the main body is, making fire support from artillery/aircraft harder to deliver accurately, and in general less engineering work is required at the front. The disadvantages of this method include a reduced window of organization, diminished time for units to study the terrain + prepared defenses, the importance placed on a covert advance, and greater vulnerability of sub-units on the march. Night marches are to transpire at rates exceeding movement in daylight conditions, despite this, 20 to 30 minute breaks are expected.

    The role of a motorized rifle battalion in a night offensive depends on the task it must accomplish. The battalion may attack on the primary axis of advance or secondary axis, within the first echelon or the second, it may be assigned to a forward detachment acting as a vanguard, or could see use in a bypassing detachment to perform specialist tasks. The approach to the line of contact is often chosen in such that the shortest possible concealed route can be taken, usually one which avoids difficult maneuvers and terrain, which would slow the advance. The width of the battalions offensive front is usually akin to what would be engaged at day, though it must be noted that if the battalion is assigned to the primary axis of advance their offensive front will be smaller than those moving to secondary axis, this is done to improve the odds of breaking through a well prepared defensive allowing for hasty occupation. The battalions combat tasks will be broken into immediate and subsequent actions, and usually seek to achieve similar depth to what would be expected during the day. The immediate tasks are those which are to be completed before dawn, and subsequent tasks are those which can be accomplished as dawn breaks, if the battalion cannot achieve its immediate objectives for any reason it will instead shift to occupy a tertiary location which is predetermined prior to the attack. The availability of lighting equipment and the training of individual sub-units for night combat affects the expected depth of the operation prior to its conduct. The pace of a unit's advance is almost always going to be slightly diminished when compared to the expected haste of daylight maneuvers, especially in rough terrain, adverse weather or with deep snow cover.

    When attacking at night it is important that a greater degree of initiative as well as independence be exhibited by sub-units involved in the endeavor due to the fact it becomes increasingly difficult to assist one's "neighbors" in complete darkness, furthermore control over the battlefield is similarly diminished. As a result, units within the first echelon are to be reinforced and receive a greater allocation of equipment for detached operation than during the day. For example, a motorized rifle battalion would be reinforced with one (sometimes two) additional tank company, divisional artillery support, one or two batteries of anti-tank guns, an anti-aircraft platoon, one or two engineer platoons, and one or two additional mechanized bridge laying systems. This ensures the complete application of firepower and maneuver capabilities which increases the breakthrough potential of the attack. If the enemy possesses an underdeveloped/insufficient defensive force, the battalion may operate as a single echelon formation, though it is more common for a two echelon system to see use, with a reserve consisting of a platoon to company sized element. These peculiarities (such as dispersing and integrating elements that would otherwise see detached operation) ensure each company is sufficiently independent while still in the support envelope of the battalion, much of this is directed towards the enemy's light support equipment and command capabilities.

 

    Light support is designed to provide advancing units with the best possible conditions for accomplishing their immediate and subsequent tasks, and to make enemy maneuvers difficult or impossible to conduct effectively. In an offensive the aims of light support center around the illumination of the enemies defensive emplacements, formations (in the interest of reconnaissance + discovering units moving to conduct a counter offensive), and creating conditions in which night vision devices can be effectively employed, as well as marking routes, the direction of enemy forces and providing general orientation on the battlefield. Light support is usually organized by the senior commander and is carried out in a similar fashion to conventional fire support plans. When advancing towards the enemies defenses and after a successful breakthrough the battalion commander receives a great deal of autonomy in regards to the volume of light support he receives. Though it must be noted that when breaking through said defenses, light support is rationed and applied mathematically just as artillery fires would be unless such actions would jeopardize the attack. Interestingly this is not the case when a battalion is detached from the main body, in this circumstance the volume of light support is entrusted entirely to its commander. It must be noted that the conservative use of light support at the outset of an offensive is a result of the proliferation of night vision devices, only the most important tasks receive a great deal of illumination vectors for this reason. Mortar platoons are usually assigned to engage native light support tasks, as well as what are known as illumination (signal) posts, which consists of two soldiers in each platoon, these work to provide intermittent light support for detection and engagement of one or two targets by direct fire . These units may also engage continuous illumination, which is usually carried out across a wide front (of roughly 2 kilometers). This is done when a counter attack is in need of repulsion or when the second echelon is introduced. To accomplish 10 minutes of continuous illumination forty 122mm flares (2x2x10 with a burn time of 35-40 seconds) would be required. If a greater level of illumination is needed, or adverse weather conditions are affecting the efficacy of the first salvo, the rate of fire and number of shells will increase to 90 pieces (3x3x10).

    As a rule, illumination should never be applied in such a way that advancing troops are "demasked", this is done by ensuring that the enemy is not illuminated beyond 0.4 lux. This also works to diminish the efficacy of enemy night vision devices. It is also important that flanks and gaps in the advance be illuminated so as to blind and expose any units waiting in ambush. When disrupting passive night vision devices it was considered important that flares ignite close to the ground. The commander must also take into account the enemies thermal imaging systems which illumination does not affect. Light support may take the form of pyrotechnic illumination flares, illumination bombs, reactive illumination cartridges, and illumination shells which are used to light enemy thermal imaging systems.

In flat, open terrain, or in the presence of snow as well as dry grass, silhouette illumination may see use, especially when the enemy is positioned out of cover (counter attacking or retreating). This allows for infantry and vehicles with similar coloration to the illuminated background (due to the application of camouflage) to be easily detected (far easier than if direct illumination was employed). Silhouette illumination is achieved by directing light support 1 km or more behind the enemy.

    Due to the proliferation of passive NVDs in the latter half of the Cold War, the use of light sources by attacking formations was deemed strictly prohibited unless protective coverings were employed to reduce the transmission of visible light and infrared rays or in unfavorable weather such as thick fog or torrential downpour. Prior to reaching the line of contact IR spotlights and other illumination vectors were not to be used. In extraordinary conditions infrared light support would be delivered over enemy positions. During the attack individual illuminators were to be used for 10 seconds at a time in alternating fashion across an entire unit, but generally speaking it was advisable to use as little individual illumination as possible during the course of an attack.

 

    Advance routes are marked with "illuminated signs", which are arranged to ensure the reliable orientation of units on the march; these usually mark turns, forks, crossroads, intersections, and hazardous areas to be avoided. In "rugged" terrain three or four signs are employed each kilometer, though this has been found to (in some cases) disorient drivers relying on night vision devices, as light sources can be seen from greater distances when such systems are employed. These illuminated signs are marked with the units insignia or a route number. Areas of contamination are to be marked with yellow lights while conventional threats and obstacles are denoted by red illumination.

    During the course of an engagement at night a battalion will need to signal its location to fire support vectors such as fixed wing aircraft, this is done through infrared illumination which display the line the unit has occupied. The lighting/signal posts or designated signal troops engage this task, this is done at the request of the commander-in-chief, and continues until the aircraft has effectively oriented itself. This helps avoid friendly fire incidents between all units involved in a given operation. To increase the ease of identification in night conditions, white marks are applied to the stern and turrets of AFVs. Infantry similarly employ white arm bands for the same reason. Though this is not an all encompassing solution, and so special mutual identification signals are employed using flares, flashlight, or infrared headlamps, for example, three short signals from an IR flashlight, this request is then met with two long signals from a green filtered flashlight. Similar requests may also be conducted over radio. Target designation is done by illuminating threats via firing flares in their direction, or tracer bullets/shells, after which a transmission identifying the targets and it's direction is given. When combating anti-tank guided missile standard and infrared spotlights will be used to achieve a dazzling effect in short bursts for 1 to 2 seconds at intervals of 10 seconds.

    When conducting fire support the enemies means of providing illumination are to be suppressed first, such as batteries and search light installations. The means in which night vision devices employed by an enemies defensive force are suppressed depends on the systems they are using. If the enemy operates primarily active or combined night vision devices, they are to be located with infrared binoculars or NVDs before the attack is conducted. The power of the infrared beam allows for the nature of the system to be determined. They may be hit with smoke, blinded or destroyed. It is much harder to defeat passive night vision devices and thermal imagers, in these circumstances it is important their application, and organization be assessed beforehand as to predict where they may be installed, though it is possible to confuse the enemy if a large volume of false targets are created, this would theoretically reduce the speed in which legitimate threats are detected.

    In regards to the offensive itself, an attack often begins with artillery preparation, which is usually shorter than what would be conducted during the day. Units advance at nightfall or when visibility is properly limited. The battalions attached artillery will advance first and take up firing positions in order to prepare for the saturation of the enemy as the unit approaches the line of contact. Behind the artillery, tanks + direct fire weapons move ahead of the infantry, who break into company and platoon columns before reaching the line of contact. Depending on the light level night vision devices will see use while the unit is on the march. During the advance forward observers with night vision devices ensure that the unit is not ambushed, while the battalion conducts "all-around" observation of their immediate position. Front and rear security elements are to operate unusually close at a distance of only three to five kilometers. Tanks are assigned to conduct direct fire using night vision sights to locate and destroy anti-tank weapons, searchlights, and other targets of importance as the engagement begins. If the attack begins as a result of direct contact with the enemy, motorized rifle units with the exception of machine gun crews, snipers and observers remain in cover until they are cleared to advance. If resistance is minimal, motorized rifles may dismount 300-400 meters from the enemy, this is done behind tanks as to reduce casualties from anti-tank fire. Tanks cooperate closely with infantry as they provide "troop surveillance" and designate targets to armored vehicles. A great deal of importance is placed on understanding valid vs mock targets, as decoys are generally more effective at night. Artillery reconnaissance vehicles such as PRP-4 may accompany tanks and make use of their thermal imaging capabilities to nullify this effect. If the enemy illuminates battalions on the advance machine gun crews and automatic riflemen specially assigned to the task will work to shoot down the flares. Due to thermal imaging systems and passive night vision making ambushes difficult to locate and even harder to thwart, reconnaissance activities are increased significantly during the offensive at night in hopes of discovering these units so that they may be destroyed or bypassed. To deceive the enemy about the location in which an offensive will transpire some units will be tasked to assault non-essential axis as to allow the main body to advance unimpeded, mock tanks may be used to further deceive the enemy into revealing ambushes without exposing legitimate sub-units.

    The importance of reconnaissance in regards to supporting an offensive at night is unprecedented. Before the night offensive is underway reconnaissance units must gain valuable insights on the composition of the enemies defense, it's capabilities, position/terrain advantages, and intentions (if they are likely to retreat or fight), they are also tasked with determining the location of nuclear and chemical deliverance systems and their readiness. Radar stations, command posts, thermal imaging systems, artillery firing positions, and reserves are also to be discovered and pinpointed. Natural obstacles such as flooding, thick foliage, and other complications must be assessed to allow the battalion to determine the engineering requirements of the operation.

    Electronic warfare is of great importance and if possible, enemy communications will be observed throughout the duration of the offensive. Ground surveillance radar, as well as aerial photo-reconnaissance conducted by both drones and aircraft will be engaged prior to the attack as to locate any objects of importance that reconnaissance units may have missed. Due to the width of the front and unique conditions of night combat, observation posts may be absent or limited in their allocation. Experience has shown that an observation post in daylight conditions can cover a 300-400 meter sector in moderately rugged terrain, at night this decreases to just 150-200 meters. This means that if a battalion were to advance on a front of up to 1000 meters they would need to establish 7-9 posts of which there are provisions to erect just 2-3. If observation posts are required they will see an increase in occupation from 3 men to 6. Special listening posts will be established to obtain information on the enemies troop movements, these posts usually consist of 2-3 men and are located as close to the enemy as possible without jeopardizing the occupants or exposing them to fire. In some circumstances a motorized rifle platoon, sometimes a tank platoon, and specifically selected NCOs are recombined into an observation group which is tasked with locating ambushes while the main body is on the march, they will often make use of a ground surveillance radar to complete this task, and will receive additional signaling equipment.

    During a breakthrough these patrols operate at a distance and provide observation and fire support for advancing sub-units. These units may even engage the enemy and conduct limited force reconnaissance to obtain further information on the composition of the defense. Raids on their headquarters, communication centers, and other facilities will be engaged as the offensive begins to disorient the opposing force, making use of the darkness to quickly retreat and re engage elsewhere. Light and sound masking are done while the battalion advances to the line of contact, improvised solutions to masking the thermal signature of vehicles are encouraged before the march begins, strict compliance with blackout measures will be ensured as to avoid discovery by the defending force. Systems such as BRDM-2 ZS-72b may be employed to cover the auditory profile of formations as they advance to the line of contact.

    Preparing For An Offensive At Night:

 

    Organizing an offensive at night emplaces unique challenges upon the commander due to the inherent complexities of the task. Beginning at the outset of decision making, the commander communicates his intentions to his subordinates, this is to be done immediately as it offers them time to study the terrain. As this is done, a comprehensive support plan is developed. He will join his subordinates at the outset of reconnaissance, where he will clarify his previous decisions from the ground with accurate terrain references. If the battalion commander is incapable of attending, he will organize the battle via a topographic map. If company commanders are unable to assess the terrain personally with their platoon commanders, the battalion commander works with the platoon commanders of the first echelon to form an accurate picture of the battlefield. It is important that reconnaissance is repeated once night falls. 

     

    If there is little time to organize an offensive, the commander receives a preliminary combat order, the battalion commanders job at this time will be to determine the best approach after assessing the situation. After which he will report to the unit commander and give instructions on how comprehensive combat support is to be carried out. If an offensive is expected to last into the night, the fire support plan and means of interaction between sub-units are planned in advance. During this transition from day to night fighting, the battalion may pursue its original objective, or receive new tasks.

    When preparing for an offensive at night, as to ensure the expedient formulation of a fire support plan, the battalion commander is encouraged to avoid waiting for further instructions from his superior officers, he must show independence and initiative. He must assess the enemy, his troops, the capabilities of neighboring units, the terrain, the NBC situation on the battlefield/expectation for NBC conditions, and the meteorological circumstances which may effect the efficacy of NVDs as well as illumination. When inspecting the capabilities of the enemy the following are accounted for: the composition, position, condition and construction of enemy fortifications, the location of key strong points, immediate and in depth firepower (anti-tank weapons + armored vehicles), the location of reserves, the presence of NVDs, the degree of training the enemy has received in regards to night fighting, their illumination capabilities, if they are operating ground surveillance radars, the quality of their night vision devices (generation), and if thermal imaging systems are present. These observations determine the order of the offensive and on which axis the main body will approach. The battalion commander must also determine the means in which counter offensives will be dealt with, the transition to fighting at dawn, the order of illumination/light support and how the enemy will be blinded based on the assessment of their night vision capabilities, how their illumination capabilities will be destroyed, and if tactical nuclear weapons are to see use.

     

    The battalion commander takes stock of the availability of material to ensure effective combat in night conditions, after which he will conclude how to distribute this material, and the most effective route to advance, offering the greatest concealment as well as fire/light support opportunities. He also analyzes what effect certain means of light support will have on the effectiveness of his battalion and neighboring sub-units.

 

    The battalion commander, after reaching a conclusion on how the terrain will effect the use of night vision devices, begins to plan where certain elements such as tanks, APCs/IFVs, and other supporting equipment would see the most effective application. He also prepares a report on how the enemies electronic reconnaissance (SIGINT) may effect the operation. After which he analyzes atmospheric transparency and it's effect on available NVDs, he also takes into account the time of year, and the likelihood of temperature drops at night, which he will use to organize preventative measures against frostbite + adverse reactions to the cold hindering the efficacy of his unit.A skilled commander, in situations where time is limited, will be able to make these decisions sequentially, with great haste.The most important factors the commander must consider when preparing a night march are the passability of the terrain, the presence of physical land marks which can be employed to orient oneself, and approaches in which the enemy has inadequate observation over.

    Once a report has been made on the previously mentioned weather, NVD and illumination assessment, the battalion commander begins formulating a light support plan. This includes what is known as the "order of illumination", which denotes the use of flare munitions during the preparatory saturation, while on the march, and once the attack begins. He will also determine when exactly NVDs are to see use alongside how illumination will function on the battlefield (when it will assist in navigation, when it will blind firing position, when it will illuminate command posts/objects of interest, and when artillery will focus on destroying the enemies light support/NVDs). Time tables are issued to each artillery unit outlining when they will provide support and when they will fire destructive munitions, each artillery unit will also receive objectives which outline what they will seek to destroy, for example, one unit may be tasked with destroying exclusively searchlights, infrared illuminators, or firing positions.

    Organizing interaction at night is exceedingly important, more so than what would be engaged at day. This is due to the fact that careful coordination between motorized rifle, and tank companies is necessary to achieve success in conditions of limited visibility. This is especially true when speaking to reconnaissance, the battalion commander must prepare the axis in which reconnaissance will be dedicated, the data they are to obtain, as well as when and how they should communicate this data so that it is integrated into the fire support plan. It is taken into consideration when motorized rifles should begin the engagement as to not sabotage a stealthy march.

    As to ensure these orders are executed without delay, preparation at the tactical level is engaged which involves political work, and the preparation of officers as well as soldiers + NCOs for the night operation at hand (including terrain study, equipment refamiliarization if needed, distributing additional communication devices, special exercises/drills, a great deal of rest if there is time to do so, and NVD operability tests). At this time the windows of vehicles will see the attachment of window film to reduce light leak and artillery pieces will move to forward positions, this is done after illumination drills have been successfully completed.

    Weapon Mounted Night Vision Devices:

    While on the march, night sights may be transported in stowage boxes, carried by soldiers (via a strap affixed to their left shoulder), or mounted on their weapons directly. Often times they will be located within an armored vehicle, and are secured in place to prevent the possibility of them breaking before reaching the line of contact. One prepares the night sight for operation by removing the battery packs from the box in which the system is stowed (if the ambient temperature drops below -5 degrees celsius it is recommended to bring a spare battery within ones coat pocket), assuming a firing position, affixing the optic (if it has yet to be attached), loading the weapon, (removing the spotlights cover if there is one), and begin adjusting the sight to accommodate the terrain as well as light level. Successful observation/accurate fire via night sights requires a great deal of training and preparation of each combatant which should be accomplished beforehand. This is due to the differences in field of view as well as coloration when compared to fighting without them. For this reason it is preferable that (despite this training) combatants observe the battlefield beforehand as to better comprehend their surroundings when effected by night conditions. NVDs such as specialized binoculars may see use to observe and detect enemy infrared spotlights as to assist in the delivery of accurate and effective fire.

    Terrain observation is to be conducted from right to left in continuous fashion, beginning with the most immediate objects and extending out to those on the edge of the optics range. Once a target has been located it is important that the nearest landmark accompany the designation as to allow for easy identification by neighboring units. The range of the target is determined by local objects which are treated as points of reference prior to the engagements transpiration, though if this was not or could not be done the size of the target and local objects surrounding it are employed to make an educated guess. To better orient oneself at night and ensure increased cohesion across the entire unit, each individual will be offered an observation sector with overlapping coverage to actualize somewhat comprehensive visibility. The best results are obtained on dark moonless nights with a great deal of air transparency.

    1PN27:

    1PN27 can detect infantry at 250-300 meters, has a magnification of 2.7x, an FOV of seven degrees, a 78mm focal length, requires a 4.5v battery to function (25 discharge cycles), consumes 0.2 amperes while operating, weighs 2.7kg when deployed (3.85kg when stowed on the march), is 450mm in length, 175mm in height, and 105mms in regards to width.

    Like most modern NVDs, 1PN27 operates via electronic-optical brightness enhancement (through an EOC or electronic optical converter). It must be noted that at the time this sight saw introduction (1967/8) it was considered a significant breakthrough due to the fact the prior generation of night vision devices relied almost entirely on infrared spotlights. 1PN27s ability to amplify ambient light was a quantum leap for Soviet night fighting.

    1PN27s two stage EOC is divided into three chambers, the first of which  contains the photocathode. A subfocusing electrode is present of which 120 volts is applied which is done to improve the quality of the EOCs screen. The second chamber has a similar focusing device of which 14 kV is supplied, and within the third chamber 15 kV, in total 38 kV is required to power the entire EOC. It is referenced as a two stage system as it increases the brightness of the image obtained by the first chamber twice.

    The EOCs circuit consists of a lens (with a relative aperture of 1:1.62), an electronic-optical converter, a symmetrical eyepiece (with a focal length of 35mm and magnification of 7.2x) and a projection system which displays the reticle via a prism (allowing for adjustment through a collimator). 1PN27 features a light filter when high ambient illumination is present (usually at dusk) made from NS-8 glass.

    The optics reticle is rather simplistic, featuring an angular mark in the center of the sight which is used when firing at stationary targets, vertical marks designed for firing at moving targets, and horizontal marks for firing the weapon when lying on one's side. Interestingly the angular mark in the center of the optic can be employed to measure the distance of a target by aligning their figure with its interior.

    The electrical circuit of 1PN27 consists of a voltage converter, an HV unit, a voltage divider, and an illumination circuit which displays the reticle. The voltage converter, HV unit and divider serve to power the EOC. The voltage converter is designed to convert the low-voltage direct current from the optics 4.5v battery into a high-voltage alternating current. The input to the AC voltage is carried out by a local oscillator on germanium transistors operating in pulse mode according to a two-cycle circuit with a common collector. The oscillator places a great deal of strain on the systems transistors as it operates continuously and therefore to reduce power consumption the oscillator must operate intermittently, this is achieved by the C1 and C8 capacitors which are connected to one another. These capacitors are charged as the oscillator functions and are discharged through resistors 1, 2 and 3. Resistor 2 is also used to select the operating mode of the voltage converter. If the system reaches an internal temperature of 40 degrees celsius the capacity of C1 and C8 decrease significantly which leads to a decrease in the oscillators operability meaning power consumption spikes. As a result a thermistor is installed which serves to decrease the temperature of the system, this is a result of the thermistors resistance increasing the discharge time of C1 and C8, which leads to a decrease in voltage output. The high voltage unit exists to rectify and multiply the 7 + 8 kV AC voltage created by the voltage converter into the 38 kV DC voltage required to power the EOC. This is done through the charging of the C2 capacitor as a result of voltage being applied to rectifier D1. Under the influence of transformer L1 the capacitor is then charged to double the voltage of rectifier D2. Afterwards, capacitor C4 is then charged through rectifier D3. Capacitor C5 will then be charged through rectifier 44 to a voltage of 24 as is C6. Lastly C7 is charged completing 7 transformer cycles. The output of the high voltage unit at this point is about 64 volts. Of course the previously described operation is in ideal conditions, voltage leaks in the high voltage unit and transformer can interfere with the process. The voltage divider consists of resistors 8, 10 and 12 each with a resistance of 10-15 ohms.

    Unfortunately 1PN27 does not offer any protection in the event of light exposure and as a result the optic is susceptible to damage or destruction if over-illuminated on the battlefield.

    1PN58 and 1PN34: 

    1PN58  can detect a tank sized target up to 400 meters, and a soldier at 300  meters, it has a magnification of 3.5x, requires a 6.25 volt power supply, consumes 7 mA under normal operating conditions, has a length of  458mm, a height of 186mm, a width of 99mm, weighs around 2kg when  deployed (3.3kg on the march when stowed), contains a desiccant  cartridge to ensure the tube stays dry, and may operate in light levels  of (3-5) 10-3 lux with an atmospheric transparency of 0.85.

    The  device operates via an electron-optical converter (EOC) (as most NVDs  do), which enhances the brightness of observed objects. The image of the  target is projected by the lens onto the photocathode of the EOC  located in the focal plane of the lens. The enhanced image is then  displayed on the EOC screen through the eyepiece. The reticle is  projected onto the photocathode through the objective lens and prism,  this is then illuminated by an LED.

    When firing a PG-7 grenade, the upper row of sighting marks is used for  aiming at a range of 150 meters, the mark labeled "2L" are to see use  when aiming at targets at 200 meters, and the lower marks are for  targets at 300 meters.

    The  sight features automatic reticle brightness adjustment provided via the  R2 photoresistor located in front of the EOC screen, this is achieved  through increasing illumination on the ground effecting the B15  photoresistor which limits the brightness of the EOP screen. The  brightness can also see adjustment from the operator via a  potentiometer.   When  the device is turned on the stabilized voltage converter produces  pulses around 1250 V with a duration of 1.5 ms (pulse duration 0.4 ms)  and a retention rate of 30-40 Hz. This voltage is applied to a high  voltage multiplier which is then directed to powering the EOC.  When  light disturbances appear such as muzzle flashes from tanks or  artillery as well as flares/light support the photocurrent increases  rapidly, leading to a voltage drop across the R-14, R-13 and R-12  resistors causing a momentary optical shut down which ensures the  survival of the sight where others (older models) would be destroyed.

    1PN34 (older generation) has a magnification of 3.5x, an FOV of 5 degrees  horizontally, and 4 degrees vertically, has a current drain of 0.27  amperes, weighs 2.2kg when deployed (3.5kg on the march when stowed),  has a length of 495mm, a height of 191mm, and a width of 96mm.

   Similarly to 1PN58, 1PN34 contains an EOC which serves to intensify target images through a photocathode which are then observed on a screen by the operator. The principles for firing PG-7L are identical with the exception of the mark labeled "2L", which is absent, as a result the "4" mark must be used for firing at targets within 200 meters instead.

     1PN34 may share a great deal of components with 1PN58 in regards to the principles the two optics operate on, but it must be noted that 1PN34 is extremely complex in comparison, meaning the optics efficiency is significantly diminished. While 1PN34 does include a regulation unit which automatically stabilizes the EOC screen in varying light levels, it is more prone to damage than 1PN58. The regulation unit consists of two automatic control circuits, one for output voltage (VPN) and the other for reticle brightness. The VPN voltage regulation circuit is a D.C amplifier on transistors T3, T4 and T6. The amplifier supply voltage is taken from the transformer and is rectified by bridge (3-6). With an increase in illumination, resistance decreases and transistor T6 is opened, resulting in the output of the VPN being connected to capacitor C1, capacitor C1 is then charged by rectifier 3-6 via the emitter collector junction of transistor T6 and locks transistor T1 and T-2. As a result the output voltage value goes down and the optic is not damaged.

   The regulation unit is also used to set the required initial brightness of the reticle lamp and to automatically maintain the screen and reticle brightness at various light levels. A breakdown of the system is as follows:  Resistor R8 is positioned on plate 1. Microswitch B and pusher 11 are secured on post 10. Post 10 is held to the cover with screws. The other end of pusher 11 is in contact with the lower end of cap 7. The second knob which maintains reticle brightness is connected to cap 7. When the knob is turned counter clockwise, pusher 11 engages microswitch B making a complete contact and switching on the sight as well as further adjusting the brightness.

 

1PN51: 

1PN51 (adopted 1983) has an infantry detection range of roughly 400-500 meters (ambient conditions depending), a tank sized target detection range of 700 meters, a magnification of 3.46x, an FOV of 9° 35’, an eye relief of 50mm, is supplied by a 6.25 volt battery, has a maximum consumption rate of 40 mA, can operate continuously for 10 hours at temperatures of 20 degrees C and 0.5 to 1 hour in temperatures of -50 degrees C, contains a desiccant cartridge to ensure the tube stays dry, weighs 2.1kg when deployed (6.45kg when stowed on the march), has a length of 276mm, a height of 210mm, and a width of 140mm making it significantly smaller when compared to the previous generation of weapon mounted NVs. The reason that 1PN51 is considered a massive advancement in Soviet NV technology is due to the EOC (EP-10), which was a single chamber electron-optical converter that not only decreased the size and weight of the optic but almost entirely eliminated fisheye. Compared to 1PN58 for example, close range operability is massively increased.

 

    The general operating principles of the optic are as follows: 1PN51 functions via an EOC (Electron-Optical Converter or image intensifier tube as it would be referenced in the West) which projects images onto a photocathode. The sights reticle is illuminated by an LED, and is then projected onto the photocathode by a prism and mirror. The intensified images of the target and the reticle are visible on the EOCs screen and are viewed through the eyepiece. A converter is used to ensure the automatic adjustment of the screens brightness under variable light conditions. Like 1PN58, 1PN51 features a protection circuit which ensures the optic is not damaged through the observation of battlefield illumination.

    The marks present on the top half of 1PN51s reticle are to see use when firing a grenade launcher up to 300 meters, the points denoted on the diagram by "5" and "7" are employed when firing a grenade launcher at ranges of 500 and 700 meters respectively, the marks located between the aiming angles denoted by "5" and "7" are used when shooting at ranges up to 600 meters, and lastly the bottom most mark is to see application when firing at targets within 800 meters (extremely unlikely).

 

    Unfortunately a comprehensive look at 1PN51s circuitry (ABC and protection circuit AL5.070.007 and AL5.121.055) is impossible to disclose as no manual or document (to my knowledge) breaks down its operating principles, but it can be assumed that they have been streamlined compared to 1PN58 due to the difference in size and weight.

    EP-10 has a sensitivity of 250 µA/lm, a resolution of 32 LP/mm, signal to noise ratio of 3.2, a spectral sensitivity of 20 mA/W at 800nm and 10 mA/W at 850nm, a diameter of 25mm, and a gain of 19000 cd/m^2 at 1×10^-4 lux. Unlike MX9644 (Western contemporary) EP-10s are electrostatically focused.
 
 

    Miscellaneous Reconnaissance Equipment: 

     

    1PN63: 

 

    1PN63 is a poorly documented head mounted night vision device which entered service around 1989. Of course the exact date in which the system entered service is difficult to discern, but I assume that due to its reference within manuals dated around the aforementioned period, that it was in use at that time. The goggles were designed for the expedient comprehension of documents in low light conditions, engineering work at night, and serving as a navigation as well as observation aid.

    1PN63 operates through two electron-optical channels. The user may focus the image perceived through these channels via manually rotating the adjustment mechanism, this is done individually for each lens. 1PN63 contains a desiccant cartridge which serves to maintain a lack of moisture within the EOC and to give visual indication which allows the user to determine if the tubes are wet or dry (annular rubber seals provide additional protection). A low voltage converter may be used which allows the device to receive power from a vehicle, if 1PN63 sees use in mechanized navigation a three-channel current stabilizer is present within this network which converts the standard 12-27V (which ensure 6 hours of operation) into a constant voltage of 1.25V. A so called "transition device" is present which is employed when operating the system in conditions where low ambient temperatures may be present. Specialized ventilation ensures the lenses do not fog in high or low temperatures, inhibiting the operation of the device. Light filters allow for 1PN63 to be comfortably operated in conditions where illumination exceeds 10 lux. Akin to 1PN51, daylight covers are present which ensure the optic is not damaged or scratched, they also allow the operability of the device to be assessed at any time of day. If light conditions are abnormally poor 1PN63 may be assisted via an IR illumination device or aided in automatic fire through the use of an IR target designator.

    1PN63 has a 40 degree FOV, a weight of 1kg, an identification range of 135 meters for infantry sized targets at an illumination of 5-10-3 lux, a diopter of + or - 4, and dimensions of 186x151x110mm. 1PN63s twin 12 kV EPV22G polyalkaline (S-20) EOCs are supplied via an onboard power supply. They have a photocathode sensitivity of 120 mkA/lm when the KS-17 filter is installed, a conversion coefficient of 150, a resolution limit of 45 LP/mm (line pair per millimeter, increase the brightness of observed terrain by 4.6×10^-4 cd/m2, and a photocathode diameter of 17mm

1PN63 owes much of its design to the OLDELFT PG1 MK2. It is very possible that the system is an unlicensed copy potentially derived from the Type-85, a licensed Chinese reproduction.

 

    1PN39 And 1PN54: 

 

    1PN39 is a night observation device designed for reconnaissance in limited light conditions. The range of the system depends on environmental factors such as the presence (or lack therefore) of natural illumination and air transparency. In favorable conditions tanks can be detected up to 700 meters and infantry up to 350 meters. The device may operate within a temperature range of -40 to +40 degrees celsius. 1PN39 can operate continuously for 6 hours at temperatures of +40 C, 3 hours at -40 C and 7 hours at +20 C. The system has an adjustable magnification which has a maximum power of 4.2x, consumes 0.3 amperes while in use, has a power supply with a output voltage of 30+2 kV, employs 2.35-2.6 V batteries, has overall deployed dimensions of 543x481x215mm (460x385x170 for the unit itself without the tripod), weighs 23.1kgs stowed on the march and 16kg deployed, and a periscopity of 350mm. 1PN39 contains a desiccant cartridge which serves to maintain a lack of moisture within the EOC and to give visual indication which allows the user to determine if the tubes are wet or dry.

 

    1PN39 functions via a two chamber (two stage cascade) EOC or image intensifier tube (6EP21MG, which has a polyalkaline photocathode).

 

     The device operates through a power source (two rechargeable batteries), voltage stabilizer, voltage converter, and voltage multiplier. A local oscillator on transistor TZ, operating intermittently, according to a single-cycle circuit, converts low DC voltage into high AC voltage. The oscillator is controlled by R4, R5 and C1, potentiometer R6 is used to set the nominal output voltage when powered by the battery, the oscillator voltage is increased by the output of transformer TR1 to -7 kV, and is fed to the voltage multiplier consisting of diodes D3-D20 and capacitors C2-C7. The constant voltage of 30 kV is taken from the output of multiplier GN1 and is fed to the EOC. If 1PN39 is connected to an external power source, 12 V are supplied to the circuit through connection Ш1, the stabilizer reduces it to 5 V. The stabilizer is formed from an emitter repeater, and a compound triode (T1 and T2). It's mode of operation is set by R1 and R3. Diode D1 protects the circuit if any complications occur when the stabilizer is connected to the system. Resistor R2 is used to adjust the nominal voltage of the power supply. 1PN39 may operate a KS-17 light filter, which is affixed via a knob which rotates between a closed position, a red filter, and a transparent filter.

 

     

    1PN54 is a day-night reconnaissance + artillery correction device which fulfills a similar role on the battlefield when compared to 1PN39. The system provides detection ranges extending out to 1500 meters for tank sized targets within light conditions of 0.003-0.005 lux. 1PN54s day channel has a magnification of 5.5x, an FOV of 6 degrees, and a periscopity of 489mm. The night channel has a magnification of 5x, an FOV of 5°18′, a periscopity of 357mm, may operate for 10 hours in temperatures between +20 and +50 degrees celsius and 0.5 hours in -50 degrees celsius. The optic itself weighs around 18.5kg, this jumps to 32kg when combined with the tripod and deployed in a fighting position. 1PN54 features flash protection to avoid damage if exposed to pyrotechnic flashes.

    1PN54 has two lenses, and covers to reduce light scattering when either channel is in use, when conducting reconnaissance at dusk a specialized diaphragm is used. At night both eyepieces are employed while at day only the left eyepiece sees application, this is because the measurement grid is only visible through the left lens.

 

    1PN54s EOC requires 30 kV to remain operational. A high voltage power supply unit is provided which facilitates the conversion of the low 6.25 DC voltage provided by the battery into the 30 kVs needed to keep the EOC supplied. 1PN54 features automatic brightness control. EP-16 (1PN54s EOC) is in many regards a clone of the EEV P8079HP, meaning they have similar specifications. Interestingly EP-16 seems to have less range than P8079HP by a factor of 500 meters, this could be a result of technological/monetary constraints or the periscopic effect of the system restricting the size of the displayed image considerably limiting it's visibility. While documentation on EP-16 itself is limited we can assume the luminous sensitivity is roughly comparable at 300 uA/lm, this also applies to the radiant sensitivity of 25 mA/W at 800 nm (20 mA/W at 850 nm), and the resolution at around 40 LP/mm. The EOC should have a gain of 100,00 asb/lx.

 

 

    PRP-3/4

    The PRP-3 is a mobile reconnaissance platform designed to fulfill a multitude of roles on the battlefield while protecting the crew from small arms fire and NBC threats. It's primary functions are "terrain observation", which denotes generalist scout work, determining the location of machine guns, ATGM teams, anti-tank guns and armored vehicles so they may be destroyed by friendly forces, and designating targets for artillery. Secondary functions include the detection of mechanized sub-units as they transition to a counter-offensive, locating defensive structures of extreme tactical importance as well as units in forward defensive positions which may endanger maneuver units, and assisting in navigation at night.

 

     PRP-3 operates the 1RL126 ground surveillance radar (K band), 1D6M1 laser rangefinder, 1PN29 night vision device, 1OP79 periscope, twelve TNPO-170 periscopes, TNP-350B day sight which is employed to assist in steering the vehicle while afloat, TNVE-1PA night vision device (supplied to the driver), GO-27 chemical and radiological alarm, 1B44 navigation device, 1G13M gyro-course indicator, 1G25-1 gyrocompass, R-124 intercom system, 6000x9000mm camouflage netting, 1000 rounds of ammunition for the PKT machine gun, two TA-57 telephones with 500 meters of cable, DS-1 stereoscopic rangefinder for supplying/establishing a second observation post, 1V520 ballistic computer for fire direction, on later models, the 1PN59 thermal imaging device and 1RL133M-1 radar. 

 

    PRP-3 is built on the chassis of BMP-1, this ensures the crew is protected against small arms fire, which allows the system to effectively integrate within motorized/mechanized sub-units. 

 

    PRP-3s crew consists of a commander, radar operator, computer operator, radiotelephone operator who also serves as the gunner, and a driver, who also functions as the vehicles mechanic.

 

    1RL126 is a pulse-doppler radar designed to detect ground targets at a maximum range of 12 kilometers (for armored vehicles) (6 kilometers for infantry) and determine their polar coordinates, this is then displayed on the radar operators screen. The radar conducts continuous scans within a sector of eighteen degrees with a frequency of 10 Hz. 1RL126 is capable of detecting stationary targets as well as those in motion, and denotes them separately on the operators screen. A horizontal line is then displayed which is used to determine the relative distance of the target, this line is formed by pulses generated by IMD-1, with each pulse corresponding to 10 meters respectively.

 

    PRP-3s navigation system allows the vehicle to measure the distance it has traveled and determine it's own coordinates on the battlefield, so that data on the location of targets relative to the system can be effectively provided. The navigation equipment aboard the vehicle also allow for the immediate transmission of topographic references to artillery so that they may prepare to fire on units observed by PRP-3.

    PRP-3 may assist in delivering light support during operations at night via a set of 9M41 flare rockets launched from 2P130-1, designed to illuminate terrain and objects of importance. These flares are electrically fired by the radiotelephonic operator, who is tasked with aligning the system with the azimuth established by the ground surveillance radar. He may also adjust the time in which it takes for the rockets to ignite once they are airborne.

     1PN59 was designed by Novosibirsk Instrument Plant in 1975 (R&D which would lead to the device date back to 1969), the system was innovative as it was the first thermal imaging system produced in the USSR, using entirely domestic technology. The optic is cooled to a temperature of 79 K by a nitrogen based high pressure gas mixture, which operates through a compressor, filter, and heat exchanger. To increase the service life of the system time control and overload protection are implemented, which will automatically shut down the device if it begins to operate outside of its mechanical limitations. The optic can be rotated from -6 degrees to 16 degrees. 1PN59 weighed around eighty kilograms and consumed 600 W of power, which were indeed disadvantages, though it must be noted that these complications paled in comparison to the advantages that thermal imaging brought to Soviet night fighting capabilities, that being accurate identification of targets out to 2000 meters. This configuration removed the illumination rockets, and left limited service in the mid 1980s on PRP-4 (around 1984 to be exact).

 

    

 

    1PN62: 

 

  1PN62 is a man-portable thermal imaging system designed to enhance the capabilities of Command and Observation Posts when operating at night and provide general reconnaissance capabilities in unfavorable atmospheric conditions (both artificial and naturally occurring). With the tripod affixed 1PN62 weighs 19kg (29kg when stowed on the march), requires 10-14.5V, consumes 0.8 amperes when operating, has an FOV of 2.5 degrees, and provides an identification range of up to 1500 meters for tank sized targets. 1PN62 itself has dimensions of 150x250x970mm, and with the tripod affixed 580×520×320mm. Under ideal conditions the observed target will have a temperature contrast of 1.5 degrees celsius when compared to the background. The device operates within a range of 8-14 μm. In regards to atmospheric tolerance, 1PN62 is functional up to pressures of 107 kPa and temperatures between positive or negative 50 degrees celsius.

 

 

1PN33 And 1PN50

 

    1PN33 night vision binoculars are designed to conduct reconnaissance and terrain observation to actualize all-around coverage when combined with weapon mounted systems. The device was often supplied to crews of PRP-3/4. 1PN33 operates within atmospheric temperature ranges of -40 to +40 degrees celsius, has a target detection range of 200-400 meters in light conditions of 10-3 lux, features a magnification of 3x adjustable down to 0.2x, an FOV of 9 degrees, requires 8.3-8.8V to remain operational (supplied via an accumulator), consumes 10mA, functions continuously for 7 hours in temperatures of +20 degrees celsius (3 hours at -40 degrees celsius), has overall dimensions of 242×178×84mm and weighs 3.5kg when stowed on the march (1.5kg deployed). 4EP14MG (1PN33Bs EOC) has a resolution of 28 LP/mm, requires 18+1-3 kV, and has a diopter of + or - 4.

    

     1PN50 night vision binoculars (I use this term loosely as the device actually operated a large biocular panoramic lens) are ergonomically superior in many regards when compared to 1PN33B, alongside offering improved detection range, limiting light leak from the EOPs screen which may be detected by the enemy, and generally increasing the clarity of the observed image. In conditions of 0.003-0.005 lux 1PN50 can detect infantry sized targets up to 450 meters, offers 8 hours of continuous operation, can function within temperatures between -30 degrees celsius to +40 degrees celsius, offers an FOV of 11 degrees, and has a magnification of 2.4x. The system has dimensions of 405x168x85mm and weighs 1.8kg. 1PN50s power supply has 5 terminals, one PC terminal for the input of 6V, a PC terminal serving as a ground or negative connection which is also connected to pin 4 of the EOC, there are two high voltage output terminals, and  lastly a screen current/feedback terminal. The PSU itself is made up of two transformers, filtering and coupling capacitors, junction field-effect transistors and potentiometers. 1PN50 can be employed in tandem with an IR illuminator which is used in conditions where natural light is absent or diminished significantly. EPM28G (1PN50s EOC) is functionally identical in many regards to EP-10 when speaking to specifications and capabilities.

Flare Rounds Employed In The Process Of Delivering Light Support:

 

    Artillery flares are designed for continuous (or periodic) illumination of enemy positions, blinding observation posts, to disorient enemy formations and to denote the location of individual units so they may be engaged by friendly manpower. The primary calibers employed for light support include 82mm-120mm mortars and 122-152mm self propelled or towed howitzers. The artillery systems most frequently tasked with delivering light support include the 2B9 Vasilek and 2B14 Podnos employing the 82mm S-832S or S-832SM illuminating shell, the 2B11, 2B16 Nona-K, and 2S9 Nona-S employing the 120mm S-843 illuminating shell, the D-30 and 2S1 Gvozdika employing the 122mm S-463 full/reduced variable flare munition or S4 "high power" full/reduced variable flare munition, and lastly the D-20, 2S3 Akatsiya, 2A65 Msta-B, and 2S19 Msta-S employing the 152mm S1 full/reduced variable flare munition or S6 full/reduced variable flare munition.

     The composition of the flares employed by these munitions often involve a mixture of metallic propellant (powdered magnesium, aluminium or a mixture of the two), an oxidizer (barium nitrate, sodium nitrate, etc), and phlegmatizers. These compounds as a rule should burn evenly, provide uniform lighting at a constant intensity, be relatively stable so that they can be stored long term, and lack hygroscopic properties. S-462s illuminating elements are comprised of 70% barium nitrate, 7% magnesium, 11% powdered aluminum, 7% aluminum-magnesium alloy (PAM-4), 2% drying oil, and 1% talcum. S-463 uses what is known as Composition 102-B which is comprised of 32% sodium nitrate, 61% magnesium, 2% graphite, and 5% resin (canifol). S-463 was also capable of employing Composition 3142 which was made from 57% barium nitrate, 27% magnesium, 13% powdered aluminum, 2% drying oil, and 1% graphite. 130mm SP-46 which was an uncommon projectile in Soviet service employed Composition 7-810A which used 68% barium nitrate, 10% magnesium, 12% powdered aluminum, 7% aluminum-magnesium alloy (PAM-4), 2% drying oil, and 1% graphite. Composition 154 found in S1 was comprised of 59% barium nitrate, 21% magnesium, 17% PAM-4, 2% drying oil and 1% graphite. Of the previously mentioned compounds, barium nitrate is used with great consistency due to its non-hygroscopic properties. Sodium nitrate, which is hygroscopic has advantages over barium nitrate, most notably it's production of yellow light which the eye is most sensitive to, but it is seen with less consistency when compared to the former.

 

    For many of the munitions described above, the internal parachute found within each of them is programmed to deploy after the shell reaches an RPM of 15,000 or reaches speeds of 400-600 m/s. Usually this corresponds with an altitude of 1-2 km, meaning the parachute opens after experiencing a dynamic pressure of 10-20 t/m2. The operating principles of these shells are as follows: once reaching the set distance the fuse is triggered which ignites an explosive charge, creating considerable pressure as well as igniting the pyrotechnic illumination composition, due to the centrifugal forces experienced by the projectile the body comes apart and the flare is released accompanied by its parachute, which opens allowing the flare to descend at a speed of 8.5-10 m/s, illuminating the surrounding area.

 

    In regards to the technical characteristics of each munition, the 122mm S-462 weighs 22.3kg, has a 2.20kg flare with 1.293kg of pyrotechnic compound stored inside, an intensity of 400,000cd, burns for 45 seconds from a maximum height of 500 meters, and operates the T7 remote fuse.

    122mm S-463 weighs 22kg, has a 1.615-1.880kg flare with 0.865-1.130kg of pyrotechnic compound stored inside, flies at a speed of 80 m/s, an intensity of 800,000cd, a burn time of 25-30 seconds from a maximum height of 400 meters, illuminates a radius of 400 meters, descends at a rate of 10 m/s, produces yellow light, and operates the T7 remote fuse.

 

    122mm S4 has a weight of 21.8kg, flies at a speed of 80 m/s, burns for 40 seconds at an altitude at 500 meters, illuminates a radius of 390 meters, produces yellow light and operates the T-90 remote fuse.

     

    152mm S1 has a weight of 40.2kg, a flare weight of 7.585kg, an intensity of 800,000cd, a burn time of 40-45 seconds from an altitude of 600 meters, descends at a speed of 8.5-10 m/s, illuminates a radius of 400-450 meters, produces white light, and operates the T7 remote fuse.

 

    152mm S6 has a weight of 39.7kg, an intensity of 1,200,000cd, burns for 55 seconds from an altitude of 600 meters, descends at a speed of 8.5/10 m/s, illuminates a radius of 400-450 meters, produces white light and operates the T-90 remote fuse.

 

 

 

    The design of flare mortars are far more simplistic and streamlined when compared to high caliber munitions fired from rifled guns, this is due to the fact they are subjected to less stress while in flight and possess a unique trajectory.

 

    The 82mm S-832S has a weight of 3.51kg, a flare weight of 0.66kg with 0.46kg of pyrotechnic compound stored inside, a range of 125-4000 meters, an intensity of 150,000cd, a burn time of 35 seconds from an altitude of 300 meters, descends at a speed of 4.1 m/s, illuminates a radius of 250-300 meters, and operates the T-1 remote fuse.

     120mm S-843 has a weight of 16.28kg, a flare weight of 1.6kg with 0.845kg of pyrotechnic compound stored inside, a range of 1000-5300 meters, an intensity of 500,000cd, a burn time of 45 seconds from an altitude of 500 meters, descends at a speed of 5-8 m/s, illuminates a radius of 300-500 meters, produces yellow light, and operates the T-1 fuse.

     120mm S9 weighs 16.28kg, has a flare weight of 1.845kg with 1.280kg of pyrotechnic compound stored inside, a firing range of 1000-5300 meters, an intensity of 1,500,000 cd, has a burn time of 45 seconds at an altitude of 600 meters, decends at a speed of 5-8 m/s, illuminates a radius of 300-500 meters, produces yellow light, and operates the T-1 remote fuse.

 

    The 90mm 9M41 illumination rocket employed by PRP-3 which is deployed from the 2P130 launcher weighs 7.9kg, has a programmable fuse which can be deployed anywhere between 3-38 seconds after launch, burns for 50 seconds from an altitude of 500 meters, has a range of 1000-3000 meters, and illuminates a radius of 500 meters.