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Found 17 results

  1. Source All Credit goes to: Mike Ennamoro and Tiles Murphy I highly recommend checking out there other articles, espically that on T-72 BLACK SHEEP Ask anybody politically savvy aged 50 and above and they will tell you that the unending string of proxy wars during the Cold War exuded a mostly artificial, but ever-present atmosphere of an imminent danger of a escalation into a full-blown nuclear world war. Fear and paranoia drove an age of accelerated technology growth predominantly concentrated in the military sector, producing various innovations which have crossed over into the non-military world. The proof is in our history textbooks today. The first rockets that sent satellites to space, for example, were modified ICBMs, and the Internet was originally a military project. New tanks sprang up like mushrooms after rain all over the world in approximately decadal increments, always to counter the last, always eclipsed by the next, but sometimes bordering on obsolescence from the moment they were created. One unfortunate example of the latter is the T-62. The T-62 is undeniably the least memorable among all of its world-famous post war era brothers - the T-54/55, T-64, T-72, T-80 and T-90 all come to mind - and it is also arguably the least historically significant among them all, but it was a step nonetheless in the evolutionary path to the modern T-14 we know today, and its relevance on the battlefield was certainly undeniable for the better part of two decades. The sentiment among the few amateur academic-enthusiasts that haven't forgotten the T-62's existence is that it was a highly mediocre design with a whopping gun, and in many ways, that is perfectly true from a technological standpoint in the evolution of armoured warfare during the Cold War. Between former Soviet tankers, however, the sentiment is slightly different. Many remember the T-62 fondly as a fairly reliable and endearing sweetheart that certainly had its own faults, but rarely ever disappointed - a sentiment echoed by Syrian and Iraqi tankers. The ones that lived, at least. Although woefully obsolete at present (it had already been totally purged from the Russian Armed Forces' inventories since 2013), it could at least boast of having the second most powerful tank cannon in the world for a few short years before being usurped by the T-64. Indeed, the sole reason of the T-62's existence was its pioneering smoothbore cannon. Tactically speaking, there were very few differences between it and its predecessor the T-54 in the mobility and armour protection departments, and the T-62 and the T-55, and indeed, both shared the same make of equipment to a large degree, thus simplifying both production and logistics. In fact, the technology of the T-62 was almost entirely derived from the T-55, and most of the interior instruments and controls are practically identical, making the transition from the T-54/55 to the T-62 wonderfully seamless. This degree of commonality wasn't entirely positive, though, because this meant that there was an unacceptable stagnation in armour technology - the type of stagnation seen on the American side of the Iron Curtain in their Patton series of tanks, which began service in the early 50's and dominated U.S Army tank units up til the early 80's. Had the designers decided to only continually modernize a T-54-type design like the Americans did with the Patton, then surely the Soviets would have never achieved the level of armoured superiority and technological excellence as they did in the late 60's, 70's and early 80's. The T-62 is an example of what Soviet tank armies could have been, but never was. It was flawed, redundant, unnecessary, and downright wasteful. But it was still valuable in its own little ways, and some of the technologies found in the T-62 even carried over to its successors. Many of its flaws (such as the U.S Army-propagated myth that it took 6 seconds to eject a spent shell casing) were in fact totally made up, but the tank was undeniably mediocre all the same. Tactically speaking, it had only a few advantages over its predecessor in the firepower department, but otherwise, the T-62 was nothing more than a more expensive T-55. It was plain to see that the T-62 was considered nothing more than a stopgap solution until the new and radically superior T-64 arrived on the scene, though it is some consolation that the T-62 was considered the most advanced Soviet main battle tank during its brief tenure. Being a mere evolutionary stepping stone, though, we can observe the way Soviet school of thought on mechanized warfare evolved with it. In the early 60's, tank riding infantry was still considered a core part of mechanized warfare. The armoured APC had arrived on the scene in the form of the wheeled BTR-152 and tracked BTR-50, but infantry were sometimes obliged to move and fight as one with a tank, and so to that end, the T-62 had handrails over the circumference of the turret for tank riders to hold on to. When the BMP-1 was introduced in 1966, it drove a major revision of contemporary tank tactics, and the shift in paradigm can be very well seen in the T-62's successors. The T-64 did not have any handrails, nor did the T-72, and the T-62M introduced in the late 60's abolished them too. The changes to the T-62 dutifully followed international trends too, most notably the global shift to jet power in the aviation industry. Too fast to be harmed by machine gun fire, the ground attack jet rendered the normally obligatory DShKM machine gun obsolete. The birth of the AH-1 Huey Cobra and the subsequent heavy use of helicopters for fire support and landing missions radically shifted the landscape, and the men and women at Uralvagonzavod obeyed. The DShKM was back by 1972. In the Soviet Union, the T-62 was produced from 1963 to 1975, with the first pre-production models appearing in 1961. After 1975, all "new" T-62s are actually simply upgraded, modified, or otherwise overhauled versions from the original production run. COMMANDER'S STATION The commander is seated on the port side of the turret, directly behind the gunner, and to his left is the R-113 radio station, created just as the T-62 first entered service in 1961. ' The R-113 radio operates in the 20.00 to 22.375 MHz range and has a range of 10 to 20 km with its 4 m-long antenna. It could be tuned into 96 frequencies within the limits of its frequency range. In 1965, the radio was swapped out for a newer and much more advanced R-123 radio. The R-123 radio had a frequency range of between 20 MHZ to 51.5 MHZ. It could be tuned to any frequency within those limits via a knob, or the commander could instantly switch between four preset frequencies for communications within a platoon. It had a range of between 16km to 50km. The R-123 had a novel, but rather redundant frosted glass prism window at the top of the apparatus that displayed the operating frequency. An internal bulb illuminated a dial, imposing it onto the prism where it is displayed. The R-123 had an advanced modular design that enabled it to be repaired quickly by simply swapping out individual modules. It is quite clear that the commander's station is the most habitable one by far in the very spartan T-62. The close proximity between all the turret occupants with each other and the shortage of breathing space makes the internal climate hot and humid, contributing to the overall discomfort. This is compounded by the fact that the crew isn't provided with any local ventilators such as fans or directed air vents, so it can get quite stuffy inside. However, the commander seems to be the most well off, since he sits right in front of the sole ventilator in the turret and he isn't required to exert himself physically, unlike the loader. Unique to the rest of the dome-shaped turret, the area around his station was cast to be devoid of any vertical sloping or rounding whatsoever, which was necessary to enable his rotating cupola to be installed. This meant that the debilitating effects of the ostensibly dome-shaped turret are completely lost on him. The cupola is mounted on a race ring. The fixed part constitutes half of the total size of the cupola, while the other half is occupied by the semicircular hatch, which has a maximum width of 590mm. The hatch opens forward, which is quite convenient for when the commander wants to survey the landscape from outside - perhaps with a pair binoculars - because being as thick as it is, the hatch is a superb bulletproof shield for protecting the commander from sniper fire. There is also a small porthole in the hatch. It is meant for an panoramic periscope tube for indirect fire. As befitting his tactical role, the commander's general visibility is facilitated by two TNPO-170 periscopes on either side of the primary surveillance periscope in the fixed forward half of the cupola, and further augmented by two more 54-36-318-R periscopes embedded in the hatch, aimed to either side for additional situational awareness. Overall, this scheme was sufficient for most purposes, but was deficient if compared to the much more generous allowance of periscopes and vision ports found on NATO tanks. The TNPO-170 periscope has a total range of vision of 94° in the horizontal plane and 23° in the vertical plane. The four periscopes in addition to the TKN-type periscope aimed directly forward gives the commander a somewhat acceptable field of vision over the turret's front arc. The use of periscopes instead of direct glass vision blocks presents pros and cons - for one, the lack of any direct vision means that the viewer's eyes is protected from machine gun fire or glass specks if the device is destroyed, but a bank of periscopes offer a much more limited panorama than vision blocks like the type found in the commander's cupola on the M60 tank. TKN-2 "Karmin" The original 1961 model of the T-62 featured the TKN-2 binocular periscopic surveillance device (above) mounted in the rotating cupola. It had a fixed x5 magnification in the day mode, with an angular field of view of 10°, allowing a nominal maximum detection range of a tank-sized target at approximately 3 km, though this was greatly dependent on geography as well as weather conditions. The periscope could be manipulated up by +10° and down by -5°, while the cupola would have to be turned for horizontal surveillance. The TKN-2 had an active night channel which picked up infrared light from the OU-3 IR spotlight attached to the periscope aperture to provide a limited degree of night vision to the commander. With a nominal viewing range of only about 300 to 400 m, the TKN-2 was all but useless for serious target acquisition at night, serving only to give away the tank's position the moment the spotlight was turned on. Performance could be improved with mortar-delivered IR flares, of course, but that doesn't count as an intrinsic merit of the device itself. Due to the fact that the periscope is unstabilized, identifying another tank at a distance is very difficult while on the move over very rough terrain. However, the commander is meant to bear down and brace against the handles of the periscope for improvised stabilization, which is adequate for when driving over a dirt road, but not when traversing over especially rough terrain. The periscope's small elevation allowance was for this purpose. The left handle has a thumb button for turning the OU-3 spotlight on or off. The OU-3 is a high-powered xenon arc lamp with an IR filter to create only infrared light. The filter isn't opaque, though, and the spotlight will glow faintly red. It is mechanically linked to the periscope, enabling it to elevate with the TKN-2. ^OU-3 IR spotlight with the IR filter removed to transform it into a regular white light spotlight^ TKN-3 "Kristal" In 1964, the revised T-62 was instead equipped with the TKN-3 pseudo-binocular combined periscope, which is a direct descendant of the TKN-2. Pseudo-binocular meaning that although the device has two eyepieces, the two optic tubes are combined to feed from one aperture, which the viewer sees out of. It has a fixed 5x magnification in the day channel with an angular field of view of 10°, and a fixed 3x magnification in the night channel with an angular field of view of 8°. The periscope can be manipulated up and down for elevation, and the commander's cupola must be turned for horizontal viewing. The TKN-3 was a sufficiently modern observation device of its time. It featured target cuing, was very compact, and had a relatively advanced passive light intensification system, but it wasn't stabilised, and featured only rudimentary rangefinding capabilities as a cost saving measure. It offered rudimentary night vision capability in two flavours; passive light intensification or active infrared. In the passive mode of operation, the TKN-3 intensifies ambient light to produce a more legible image. This mode is useful down to ambient lighting conditions of at least 0.005 lux, which would be equivalent to an overcast, moonless and starless night. In these conditions, the TKN-3 can be used to identify a tank-type target at a nominal distance of 400m, but as the amount of ambient light increases such as on starlit or moonlit nights, the distance at which a tank-sized target is discernible can be extended to up to 800m in dark twilight hours. Any brighter, though, and the image will be oversaturated and unintelligible. The active mode requires the use of the OU-3K IR spotlight, which is practically identical to the OU-3 performance-wise. With active infrared imaging, the commander can identify a tank at 800m, or potentially more if the opposing side is also using IR spotlights, in which case, the TKN-3 can be set to the active mode but without turning on the IR spotlight. Rangefinding is accomplished through the use of a stadiametric scale sighted for a target with a height of 2.7 m, which is the average size of the average NATO tank. Like the TKN-2, the TKN-3 is unstabilized, making it exceedingly difficult to reliably identify enemy tanks or other vehicles at extended distances while the tank is travelling over rough terrain, let alone determine the range. The left thumb button initiated turret traverse for target cuing, and the right thumb button turned the OU-3K spotlight on or off. The range of elevation is +10° to -5°, just like the TKN-2. The OU-3K spotlight is also directly mechanically linked to the periscope (the arm to which the spotlight is linked to can be seen in the photo above) to enable it to elevate with the TKN-3. Target cuing is done by placing the crosshair reticle in the periscope's viewfinder over the intended target and pressing the cue button. The system only accounts for the cupola's orientation, though, and not the periscope's elevation, so the cannon will not elevate to meet the target; only the turret will. Because the cupola did not was not counter rotated as turret traverse was initiated, it will be spun along with the turret as it rotates to meet the target cued by the commander, potentially causing him to lose his bearings. To prevent this, there is a simple U-shaped steel rung for him to brace with his right arm as he uses his left hand to designate the target. This wasn't as convenient as a counter rotating motor, of course, but it was better than nothing. Ventilation for the crew is facilitated by the KUV-3 ventilator, identifiable on the rear of the turret as a large, overturned frying pan-shaped tumor on the rear of the turret. A centrifugal fan inside the ventilator housing sucks in air and performs some low level filtration, ejecting dust and larger particles out of a small slit at the base of the housing (refer to photo above), and then released into the crew compartment, passing through a drum-shaped NBC filter unit inside the tank proper. The air can be optionally cleaned of chemical and biological contaminants by the filter in contaminated environments where the centrifugal fan is simply not enough. The filter unit also contains a supercharger to increase the positive pressure inside the tank to produce an overpressure, preventing chemical and biological agents from seeping into the tank. Notice the PVC pipe connecting it to the ventilation dome on the outside of the turret rear But being the commander is still a mixed blessing, because his seat is seated right in front of the hydraulic pump, subjecting him to more acoustic fatigue than anyone else in the tank (the green canister is the hydraulic pump). Nevertheless, the commander's station is the second most roomy one in the tank, besides the loader's station. Here in the photo below, you can see his seat back and the few pieces of equipment that he is responsible for. Sometime during the 70's, a select few T-62s received a shield of sorts over the commander's hatch. It is a sheet steel face shield with a canvas skirt draping down. Being so thin, the face shield is not bulletproof, though perhaps resistant to hand grenade fragments and small mortar splinters. Since it doesn't really do very well as ballistic protection, the main function of the shield appears to be to conceal the opening of the commander's hatch to disguise his exit from the prying eyes of snipers, and to keep away dust if the commander feels like sitting outside during road marches. Either way, not many T-62s received the addition, though almost all T-72s did. The reason for the bias is unknown. GUNNER'S STATION The gunner is squeezed into his corner of the turret, wedged between the turret wall to the left and the cannon breech to the right, and between the commander and the sights. It is so cramped that the commander must partially wrap his knees around him. As was, and still is common among manually loaded tanks, the gunner doesn't have a hatch of his own. Instead, he must ingress and egress through the commander's hatch. The biggest flaw with this layout is that if the commander is unconscious, incapacitated or killed, then the gunner will suddenly find it extremely difficult to leave the tank unless the commander was somehow completely vaporized. Even worse, if the tank has been struck, there is a very distinct possibility that the interior is catching fire. Plus, another flaw with the layout is if the turret was perforated through the front on the port side cheek, both the gunner and commander would be killed, effectively rendering the tank useless in combat. For extra visibility, the gunner has a single TNP-165 periscope pointed forward and slightly to the right, though for what exact purpose this lone periscope is meant for is unknown, since the field of view from it is so small that the gunner can't really see very much, nor can the commander seated behind him. It is more useful for the commander for checking directly in front of the tank. In addition to all of the necessary switches and toggle buttons to activate this and that, there are also some other odds and ends at his station, including a turret azimuth indicator, which is used to orient the turret for indirect fire. It is akin to a clock, having two hands - one for general indication measured in degrees, and the other in 100 mil increments for precise turret traverse. SIGHTING COMPLEX TSh2B-41 sight aperture port, with nuclear attack seal in place The gunner is provided with either a monocular TSh2B-41 or a TSh2B-41U (in later models) primary sight and a TPN-1-41-11 night sight, which also functions as a backup sight in the event of the failure or destruction of the primary sight. TSh2B-41 The TSh2B-41 is a monocular telescopic sight, functioning as the gunner's primary sight for direct fire purposes. It has two magnification settings, x3.5 or x7, and an angular field of view of 18° in the former setting and 9° in the latter setting. As was and still is common for all tank sights, it has an anti-glare coating for easier aiming when facing the sun. It comes with a small wiper to clean it from moisture, and it comes with an integrated heater for defrosting. Like most other tanks of its time, the T-62 lacked a ballistic computer, but it was also unusually deficient in the rangefinding department. For rangefinding, the gunner had to make use of a stadiametric ranging scale embossed on the sight aperture. Compared to optical coincidence rangefinders, stadia rangefinding was terribly imprecise, but also much simpler in both production and employment, and much more economical than, say, optical coincidence rangefinding. In fact, stadia rangefinding is essentially free, since all that is needed are some etchings into the sight lens. The savings made from the exclusion of an optical coincidence rangefinder were enormous, amounting to many thousands of rubles. Ranging errors of up to several hundred meters is often the norm, especially if some of the lower part of the target vehicle is obscured behind vegetation or other terrain features. It isn't uncommon for the first shot on faraway tank-sized targets to fall woefully short or fly clear over. Below is the sight picture: From left to right: APFSDS, HEAT, HE-Frag, Co-Axial Machine Gun When the gunner has obtained range data, he manually enters the necessary correction into the sighting system by turning a dial. The dial adjusts the sight to calibrate it for that range. Calibration is when the chevron is elevated or depressed to account for range. If the target is very far away, for example, then the chevron will be dropped significantly, forcing the gunner to sharply elevate the gun to line up the target with the chevron, thus forming a ballistic solution. Because APFSDS, HEAT and HE-Frag shells all have different ballistic characteristics, the gunner must refer to a set of fixed range scales drawn on the upper half of the sight in order to get the proper gun elevation. For instance, if the target is 1.6 km away, and the gunner wishes to engage it with high explosive shells, then he must line up a horizontal bar (which moves up and down with the targeting chevron but at different speeds due to a reduction gear) with a notch on the range scale for "OF" shells that says "16". If the gunner wishes to use APFSDS instead, then he need only line up the horizontal bar with the "16" notch on the "BR" scale. Then, the chevron will show how much supraelevation is needed in order to hit the target with the selected ammunition. The gunner will then lay the chevron on the target and open fire. The sight has an internal light bulb that when turned on, illuminates the reticle for easier aiming in poor lighting conditions such as during twilight hours or dawn. Unless the gunner had 20/20 vision and the tank was completely still, considerable ranging errors in the neighborhood of 100 or so meters was the norm, and as the distance from the target increased, the accuracy of the measurement decreased exponentially, deteriorating drastically past 2000 m. As such, it is more difficult hitting targets with lower velocity ammunition like HE-Frag and HEAT shells, and even harder for moving targets. However, the inclusion of near-hypersonic APFSDS ammunition in the T-62's loadout greatly helped counterbalance this issue, making it markedly easier for the gunner to hit both stationary and moving tank-type targets, while most targets requiring HE-Frag shells like machine gun nests and pillboxes and other fortifications would be stationary anyway, thus making pinpoint accuracy much less of a priority. Even so, on account of the extremely high speed of the APFSDS rounds fired from the 2A20 gun, the sight can be battlesighted at a very generous 1000 m, allowing the gunner to confidently hit a tank of NATO-type dimensions at any distance between 200 to 1600 m by aiming at center mass without needing to ascertain the range beforehand. However, one inescapable flaw of the TSh2B-41U was that it lacked independent vertical stabilization, being directly mechanically linked to the 2A20 cannon, forcing it to elevate with it when the loading procedure is underway. This causes the gunner to (very annoyingly) lose sight of anything he is aiming at at the moment, making the commander's the only pair of eyes to observe the 'splash' and give corrections or search for new targets. This led to the development of the independently stabilized TSh2B-41U.
  2. RD-0410

    Also posted here. RD-0410 The history of American efforts to develop nuclear thermal rockets is relatively well known. Similar Soviet efforts have remained far more obscure. However, during the Cold War, the Soviet Union developed and tested an advanced nuclear thermal rocket engine, designated the RD-0410. Unfortunately, relatively little English-language information about the RD-0410 can be found (at least in easily available sources). Similar to the American NERVA program, development of Soviet nuclear rocketry began in the mid-1950s. Serious research began in 1955, with development of a rocket beginning in 1956 (the people working on this project included such notable people as Kurchatov, Keldysh, and Korolev). Initially, the Soviets planned to use the nuclear rocket to power an intercontinental ballistic missile, or possible a cruise missile. However, it was quickly realized that chemical rockets were good enough for suborbital flights. As a result, by the 1960s, it was decided to develop the engine for usage in space. The engine was developed by the KBKHA bureau, which had also developed engines such as the RD-0105 (used on some derivatives of the R-7). The goal was to develop an engine with a specific impulse of roughly 800-900 seconds, double what can be achieved with normal chemical rockets. Doing this would require creating a nuclear reactor that was both very light, and capable of withstanding very high temperatures around 3000 Kelvin. I have seen a few references to a program to develop a 2,000 isp engine, but this would require temperatures (over 15,000K) well in excess of what was possible in the 1950s (or even today) for a solid core design. The test site selected for the Soviet nuclear engine was Semipalatinsk in Kazakhstan, a remote location similar to Jackass Flats in Nevada. The Soviets had already tested numerous atomic weapons (including their first in 1949 there), so the place was no stranger to nuclear activity. It appears that tests of the engine were conducted in a mine shaft approximately 150 meters deep, unlike the American NERVA, which was tested aboveground. Most likely, this was due to concerns over radiation should the engine malfunction. At some point, the engine acquired the designation RD-0410, it is less commonly known by its GRAU designation 11B91. That the engine received a GRAU designation means that it was almost certainly considered for military applications. The American NERVA had a thrust of approximately 330 kilonewtons. This was much more than the RD-0410, which had about 35 kilonewtons. This was both by design, and due to political/monetary considerations. The Soviet government had somewhat lost interest in the project once it had become apparent that the nuclear engine was not usable as an ICBM upper stage. More importantly, by developing a lower power engine, the reactor assembly as a whole would be smaller. The RD-0410, including propellant, was planned to mass roughly 15 tons when completed; putting it well within the payload capabilities of Soviet launchers like Proton. The actual engine itself weighed only about two tons. In contrast, the American NERVA was much heavier, and could only be launched by a Saturn V or similar vehicle. There were other important differences between NERVA and RD-0410. The NERVA’s fuel elements were hexagonal in cross section, with several holes drilled in them for hydrogen to pass through. Hundreds of these elements (each about an inch wide) made up the NERVA’s reactor. NERVA Fuel Elements It has been difficult to find exact information about the geometry of the RD-0410’s fuel rods, however, it appears that they had a complex shape. The fuel rods were twisted, and had a complex cross section, shaped like the petals of a flower. This was intended to lock the fuel rods together, and prevent fuel from falling out of the reactor if a few rods cracked or became dislodged. The fuel elements were made of uranium carbide, in order to better withstand the high temperatures of the core. Development and testing of the RD-0410 proceeded slowly. By 1973, America’s NERVA had already been test fired, then cancelled before actually flying. However, large scale tests of the RD-0410’s components did not begin until 1978. The test reactor was first started on March 27, 1978, and ran for 70 seconds. Gradually, the reactor was run for longer, and at higher temperatures. By 1981, the RD-0410 was running for an hour, its design duration. A specific impulse of 910 seconds was achieved; this was superior to that which was obtained with NERVA. The American Timberwind/SNTP project from the late 1980s planned to achieve similar efficiency with much higher thrust to weight, but it encountered numerous technical problems and did not reach the test stage. All accounts of the RD-0410 state that it’s testing at Semipalatinsk went very well. Originally, it was planned that the engine would fly in 1985 (likely replacing the Block D 4th stage on Proton). However, as the Soviet Union imploded during the 1980s, development slowed, then halted. Other Soviet nuclear rockets were planned, such as the RD-0411; a high thrust (~400 kN) engine that would have been used on a Mars mission, and an engine designated 11B97, which would have had the capability of either nuclear thermal or electric propulsion. However, like all other nuclear rocket programs, none of them came to be. via Astronautix, a concept for a Soviet Mars spacecraft, that likely would have used RD-0411 Important Stats: Unfueled Mass: ~2,000 kg Total Stage Mass ~14,000 kg Thrust: 35 kN ISP: 910 sec Maximum Run Time: 3600s Height: 3.50m Diameter: 1.6m Bibliography: http://www.astronautix.com/engines/rd0410.htm http://www.popmech.ru/made-in-russia/5983-k-marsu-na-reaktore-vzryvnaya-sila/ http://www.cosmoworld.ru/spaceencyclopedia/programs/index.shtml?yard.html
  3. In 1944 the Red Army began looking for a replacement for the battle proven T-34. Their initial action was to simply up-gun the T-34 again, this time with the 100mm D-10T from the SU-100. However deficiencies in the transmission prevented this plan from coming to fruition. As a result the Red Army turned to the T-44. Relying on experience gained from the T-44's own up-gun project they created what was called the T-44B. Given the major changes compared to the current T-44 they later changed the name to the T-54. Designed by A.A. Morozov between October 1944 and December 1944 it had reached sufficient development by November 1st 1944 that People's Commissar of Tank Industry of the USSR V.A. Malyshev ordered Factory №183 to produce a prototype. The factory built the original prototype by January 30th 1945 where until mid-February it underwent testing. On February 22nd it was sent to a NIBT training ground to undergo government testing. Despite identifying several flaws such as a lack hydraulic shock absorbers for the road wheels the T-54 was deemed superior to all existing domestic designs and recommended for eventual adoption. T-54 (first prototype) They had reason for their claim; with a transverse mounted engine and a torsion bar suspension the T-54 was much smaller than the T-34. This size decrease allowed the Soviets to significantly up-armor the tank without greatly increasing the weight. The front hull was 120mm thick angled at 60 degrees, the turret was 150mm thick. Despite the armor increases the T-54 only weighed 35.5 tons. Despite the wishes of of the Soviets (who wanted a 700hp engine on their T-34 replacement) the venerable V-2 sill powered the T-54. With an output of 520hp the T-54 was capable of 43.5 km/h. In addition to the increased armor the T-54 was armed with the 100mm D-10T-K gun which was capable of 7-4 rounds a minute. Like other Soviet tanks the turret design limited gun depression with only -3. So despite only being 35.5 tons the T-54 had comparable firepower and armor protection to the 45 ton IS-2. Armor of the T-54 (first prototype) In response to the deficiencies identified by the Red Army Factory №183 created another T-54 prototype. Still designated T-54, though by this point in time it would receive it's GABTU designation of Object 137. The tank was produced in July 1945 with government testing beginning in July and ending in November of that year. The T-54 second prototype had many changes, the hull and turret were redesigned, the transmission was replaced with a different one, the gun was replaced with the 100mm LB-1, among other changes. The new turret was up-armored to 200mm thick. In combination with the new gun and turret the T-54 second prototype had increased gun depression compared to the original with -5. All of these modification caused a weight spiral to 39.15 tons, which with the same V-2 engine as before the speed was reduced to 42.5 km/h. As before the Soviet Government recommended it for Red Army service along with the corrections of some defects. T-54 second prototype (Object 137)
  4. This thread will be about Soviet cars, racing vehicles and SRS BSNS cars. More photos, less text! Moskvich 404, 1954. Moskvich 407 Coupe Moskvich-G1, 1955 Moskvich-G2, 1956 Another Moskvich-G2 Moskvich-G3, 1961 Moskvich-G4, 1963 Moskvich-G4A, 1965 Moskvich-G5, 1968 Moskvich-G5M, 1974
  5. Basic History State of PVO before MiG-25 During the middle part of the 1950s, the PVO (Soviet air defense forces) were poorly equipped to deal with future threats. The majority of its interceptors consisted of aircraft such as the MiG-15, MiG-17, MiG-19, and Yak-25. These aircraft possessed sufficient performance to take on American bombers such as the B-29 and B-50, and were at least marginally capable of intercepting jets like the B-47 or B-52. However, they were horribly inadequate against coming bombers, such as the B-58 Hustler (which first flew in 1956). The arrival of Mach 2 capable interceptors such as the Su-9, and later the MiG-21 in the latter portion of the 1950s evened the playing field somewhat. However, these interceptors suffered from severe deficiencies. The Su-9 (and to a lesser extent the MiG-21) had a cripplingly short range, a major shortcoming when defending a country as large as the Soviet Union. The Yak-27, a development of the Yak-25, had better range than either of the deltas, but was inferior in terms of speed and altitude. In addition to various performance issues, the PVO’s interceptors were also handicapped by poor armaments. The Kaliningrad K-5 (NATO AA-1) radar guided missile was equipped by most PVO interceptors following its introduction in 1955. Though decent for its time, it was limited by its beam riding guidance and short range. The infrared guided K-13 (AA-2) was introduced in 1960 after being hurried copied from a captured AIM-9B. Like the K-5, the K-13 suffered from poor range, and was also limited to being fired at the rear of a target. These systems would clearly not be sufficient to reliably destroy the B-58, let alone the Mach 3 capable XB-70 (which began development in the late 1950s). The introduction of surface to air missiles such as the S-25 and S-75 had some promise (as demonstrated by the destruction of a U-2 reconnaissance aircraft by an S-75 on May 1 1960 at over 18,000 meters). However, these missiles required large fixed launch sites, leaving them incapable of covering large swaths of territory. In an environment where a single bomber was capable of destroying a whole city, the situation was clearly unacceptable. It was clear that a new interceptor was needed to equip the PVO. Numerous solutions were tried. A modified variant of the MiG-19, the MiG-19SU was tested. This aircraft was fitted with liquid rocket engines in addition to the two RD-9s, giving (briefly) improved speed and altitude capability. This allowed flights to over 20,000 meters , however, the aircraft suffered severe controllability issues. In any case, it was clearly a temporarily solution. Another program was the development of various ‘heavy interceptors’, capable of engaging NATO bombers at extreme range, well away from populated areas or strategic targets. These included the abortive La-250, and more successful Tu-128 (developed from the Tu-98 bomber prototype). Though the Tu-128 entered service (indeed, it continued on into the early 1990s), it did not arrive until the middle of the 1960s. Even then, it was a large and ponderous aircraft, capable only of transonic speeds and completely lacking maneuverability. It could not serve as the PVO’s primary interceptor. An effort with more potential was the Sukhoi T-37. This aircraft was broadly similar in planform to the Su-9 (being a tailed delta) but was much larger. Powered by an R-15-300 engine, it was planned to reach speeds near 3,000 km/h at altitudes approaching 25,000 meters. Interestingly, it was also to have been fitted with equipment enabling it to be flown automatically under ground control (the US had the SemiAutomatic Ground Environment, a similar system capable of directing F-106s). However, it was plagued by numerous issues, and was scrapped in 1960 before it ever flew. Requirements The requirements for the MiG-25 were greatly determined by its potential adversaries. The main threat was the B-58 Hustler, capable of Mach 2 at altitudes approaching 18,000 meters. In 1960, the Soviets became aware of yet another threat; a Mach 3 successor to the U-2 was under development (this was the A-12/SR-71, though the Soviets did not know this initially). As a result, it was decided that the new interceptor should be capable of flight at up to Mach 3, and at altitudes in excess of 20,000 meters. Coincidentally, the VVS (Soviet Air Force, separate from air defense forces) was looking for a new high speed reconnaissance aircraft during the late 1950s. At the time, most of the VVS reconnaissance force consisted of variants of the Il-28 or Yak-25. The survivability of these aircraft against new NATO fighters such as the F-104 or Lightning was marginal at best. The Yak-25RV was in development, and promised comparable performance to the U-2 (it did not fully deliver), but this was an incremental step at best. A wholly new aircraft with exceptional performance was needed. By 1960, it was realized that the new recon aircraft had broadly similar requirements to the new PVO interceptor program (by then in development for over a year), so the programs were merged. The ability to carry photorecon equipment was added as a requirement to the interceptor program. Development The Ye-150/152 can be considered the direct ancestor of the MiG-25. Developed in the late 1950s and first flying in 1960, the Ye-150 was broadly similar in appearance to the MiG-21, but was significantly larger and was capable of reaching much higher speeds. The Ye-152 was a further development; it was fitted with R-15-300 engines, the same R-15s which would be fitted to the MiG-25. Like the Ye-150, it represented a massive performance leap over the MiG-21, but it was very much a testbed. The R-15s were supremely unreliable (early models had an average engine lifetime of roughly 20 hours), and the weapons system was tempermental. There was also the Ye-152A, which was fitted with two R-11 turbojets (the same engine as the MiG-21) instead of a single R-15. Though these aircraft did not enter production, they provided the Mikoyan-Gurevich design bureau with valuable data on high speed flight and the R-15 engine. There is some uncertainty about the initial genesis of the MiG-25 program. There are rumors that Mikoyan instructed chief designed Seletisky to develop an interceptor similar to the North American A-5 Vigilante (which had first flow in late 1958) powered by two R-15-300s. Other sources state that work began before the first flight of the A-5. While there are obvious similarities in layout between the A-5 and MiG-25, there are also massive differences. At most, the MiG-25 was somewhat inspired by the A-5, and is very much not a ‘clone’ or reverse engineered copy. (Later proposed Vigilante derivatives such as the NR-349 or rumored J58 powered version would have been much more analogous to the MiG-25). The new aircraft was assigned the designation Ye-155 by Mikoyan (the prefix Ye for yedinitsa denoting a prototype or testbed aircraft). It was decided very early to use the R-15-300 engine. However, there remained uncertainty as to the layout of the engines. Though a conventional side by side layout was ultimately chosen, a vertically stacked layout (such as on the English Electric Lightning) was also considered, as was a staggered engine arrangement (as on the I-320 prototype). Unlike previous Mikoyan-Gurevich designs, it was decided not to utilize a nose mounted intake, but instead place the intakes under the wings. This allowed for a smaller fuselage (in both length and cross section). The underwing intake placement worked well with the shoulder mounted wing placement, which was needed to allow for the carriage of very large AAMs. This wing layout also allowed the wings to be constructed in one piece, simplifying constructing and improving structural rigidity. Numerous planforms were proposed for the wing before the design of the prototype was finalized. At one point variable geometry designs were considered (this would have significantly predated the introduction of the Su-17, though variable sweep designs had been studied at least since 1945). The variable sweep design was seriously considered enough that a model of a recon MiG-25 with variable geometry was made, it somewhat resembles an F-14. One of the benefits of the variable geometry design would have been improved takeoff and landing performance, however, it was decided that this was not worth the added complexity and weight associated with such a design. Following numerous wind tunnel tests, a trapezoidal wing of low aspect ratio was chosen. As with many Soviet designs in the 1950s and 1960s, lift jets were considered for use to improve takeoff and landing distance. The proposed STOL design would have used two small RD36-35 lift engines, mounted in a slightly staggered arrangement in the fuselage, with intakes along the back of the aircraft. While the lift jets would likely have improved takeoff and landing distances greatly, they also decreased the internal volume available for fuel. This was a serious drawback, especially for the reconnaissance version. As a result, the lift jets were discarded, with the STOL design not progressing beyond the model stage. As the MiG-25’s design grew closer to being finalized, materials selection became a serious issue. The leading edges of the wings, inlets, and nose of the aircraft would experience extremely high temperatures at Mach 3, well above the melting point of conventional aluminum alloys commonly used in aircraft construction. Alternative materials had to be found, and many were considered. At first, titanium seemed a logical choice. It has excellent thermal properties, is quite strong for its weight, and the Soviet Union possessed large reserves of the material. However, the Soviet aircraft industry had little experience working with titanium, which was notoriously temperamental (for instance, when manufacturing the SR-71, Lockheed engineers were forced to use special tools, as normal tools contained cadmium, which made the titanium brittle). In particular, the automated welding methods commonly used in Soviet aircraft manufacturing plants would not be suitable for titanium. As a result, it was decided to use steel alloys for the majority of the MiG-25s structure (titanium was used in some areas, but at much lower quantities). Initially, there were some doubts as to whether certain components (such as the integrated fuel tanks) could be made strong enough without seriously increasing weight, or absorbing the cyclical flight loads. Tests showed that this was not the case, and the MiG-25 ended up being built using large quantities. In addition to the issues with materials selection for the aircraft structure, the thermal loads associated with high speed flight caused trouble in other areas. Normal lubricants and hydraulic fluid would break down at the temperatures the MiG-25 would experience, and normal canopy glass would melt. In many ways, this mirrors the problems faced by the Skunk Works team designing the A-12 at around the same time. Throughout 1962 and 1963, the design of the MiG-25 was further refined. In 1963, construction began on the first prototype, Ye-155R1. Its completion took most of the year, and it was not rolled out from the Zenit Machinery Works (the common name for the MiG bureau’s experimental aircraft factory) until December. Despite this, Ye-155R-1, a prototype of the reconnaissance variant, was missing much of its operational equipment. Still, it had more than enough to validate the basic flight characteristics of the airframe. In addition to lacking various pieces of equipment, Ye-155R-1 differed from production MiG-25s in several ways. For one, the aircraft had a pair of 600 liter fuel tanks mounted at the wingtips. These both increased fuel capacity, and prevented flutter. Ventral fins were attached to the fuel tanks, to improve lateral stability at high speeds. Both of these features would be absent from production MiG-25s. Ye-155R-1 also had provisions for the fitment of canards to the sides of the forward portion of the air intakes; these would have been used for pitch control at high Mach numbers, but they were never installed. The first prototype suffered from numerous issues. Among the most serious of these was roll control issues in the transonic regime, in some cases severe enough to render the aircraft uncontrollable. The wingtip fuel tanks caused vibration as fuel was depleted and sloshed about. The intakes were inefficient at high Mach numbers, and the aircraft’s static margin decreased as well. Finally, Ye-155R-1 was overweight, causing its range to fall short of the target. The second prototype, Ye-155R-2, was also a prototype of the recon MiG-25. This aircraft was broadly similar to the previous prototype, though it did incorporate some refinements. There was one immediately obvious difference; the wingtip fuel tanks were deleted. This would be the last prototype built at the Zenit plant; the factory was tasked with producing the first MiG-23 prototypes, and had no more room for further Ye-155s. As a result, it was decided to build prototypes from Ye-155R-3 onward at Mikoyan’s Gorkii plant, the same as would produce the production aircraft. This resulted in a delay in producing Ye-155R-3 as the factory was retooled, but it would ultimately allow production to commence quicker. Ye-155R-3 was a milestone in and of itself; it was fitted with a full suite of photorecon equipment, and would be used for testing various camera arrangements (among other things). Belenko Defection Later Variants Post-Soviet service Variants Prototypes Ye-155 models Operational MiG-25P/PD/PDS Export MiG-25P MiG-25RB MiG-25R MiG-25BM MiG-25PU Other Ye-266M Ye-155MP Buran testbeds / training aircraft Various other concepts and variants Production In Red Air Force Service Other Operators Combat Performance Egypt vs. Israel Iraq MiG-25 vs. SR-71 Structure Materials Engines Electronics Radar Early versions vs. Later Recon variants - cameras Armaments Air to Air MiG-25P MiG-25PD Ground MiG-25RB MiG-25BM Other Systems of Note Citations http://www.kamov.net/russian-aircraft/mig-19su/ http://www.kamov.net/russian-aircraft/sukhoi-t-37/ MiG-25 'Foxbat', MiG-31 'Foxhound': Russia's defensive front line By: Gordon, Yefim. Aerofax 1997 Skunk Works: a personal memoir of my years at Lockheed By: Rich, Ben R., and Leo Janos. Little, Brown 1994
  6. Today somebody sent me an email asking if I had any material showing what the bottom of the T-34 looked like. Glancing through my books on the topic, none really show this view of the vehicle. The guy asking is working on a series of T-34 models and wants as much detail as possible. Anyone got something on this?
  7. Soviet Artillery Doctrine

    I'm doing some research on cold war era Soviet artillery doctrine and was wondering if anyone had any actual Soviet resources. No need for translations, I can read Russian. Right now I have the FM 100-2.1 The Soviet Army:Operations and Tactics from my Army days and some NATO books that really only talk about what we knew from "observational reports". I also have some Soviet artillery survivabilty manuals and Soviet artillery order of battle data but I'm have some trouble with actual artillery unit manuals and the like. Anyone have a good source?
  8. Information Wanted: Project 701

    While doing research on the MiG-25, I came across a couple mentions of something called Project 701. Supposedly, it was a planned replacement for the MiG-31, and was being developed during the late 80s (but never was built). I've seen a couple different conceptual designs posted, of which this one seems the most plausible; Although the planform is more than a bit odd for a design that was supposedly to have had low observability features (also, dorsal intakes on a fighter is wrong to me on a visceral level). If anybody has any more information on this, please post it here.
  9. The Yakovlev VTOL Family

    During the latter part of the Cold War, the Yakovlev design bureau came up with quite a few designs for VTOL combat aircraft. While they weren't the most successful designs, they are pretty interesting, from both a historical and technical standpoint. The first of these is the Yak-36 (Freehand); While the Soviets had come up with numerous other VTOL designs in the 1960s, most of them used dedicated vertically mounted engines to take off vertically. However, the Yak-36 had a more modern arrangement, with two engines that used vectored thrust for both vertical and horizontal flight. The Yak-36 was powered by a pair of R27-300 jet engines (the same engines that powered the MiG-23 'Faithless' VTOL concept). In addition to providing vertical and horizontal thurst, the engines also provided airflow for 'puffers' at the wingtips, nose, and tail, which provided control in hover and low speeds (where aerodynamic controls would not be effective). The Yak-36 suffered from various difficulties during its development, among them the engines reingesting exhaust gases. At least two of the prototypes crashed at somepoint. Though the Yak-36 was at various points displayed with underwing armaments (such as rocket pods), it was never deployed to operational units; it was solely used as a testbed. Following the Yak-36 was the more widely known Yak-38 (Forger). It entered service in the early 1980s. Unlike the Yak-36, the Yak-38 was fitted with lift jets (two RD-36V engines). Though these engines did an adequate job of providing vertical lift, they had the drawback of being dead weight in horizontal flight. Horizontal thrust was provided by a single R27-300. Though the Yak-38 was capable of VTOL, it had highly limited performance; it was strictly subsonic, and had marginal payload capability. (pictured: unrestrained optimism) The Yak-38 was designed from the outset as a combat aircraft, intended to be deployed from the Soviets' Kiev class carriers. In this role, it was shit (much like your favorite anime). The first issue was reliability; many of the Forger's components proved to be horrendously unreliable, especially the lift jets. I've seen figures stating that the lift jets had an average lifetime of less than 25 hours, which leads me to suspect they were actually rebranded Jumo 004s. Engine failures were especially bad in the Yak-38 - a failure of a lift jet on one side would lead to the jet entering a fast, unrecoverable roll. The lift jets also had poor thrust in hot conditions; in many cases, the Yak-38 had to fly with only two pylons filled, rather than all four. Considering that the Yak-38 had no internal armament, this was not optimal. Interestingly, in addition to using it as a carrier aircraft, the Soviets also trialed the Yak-38 as a close air support in Afghanistan. This was less than successful; the Yak-38 was only capable of carrying a pair of 100kg bombs, markedly inferior to dedicated CAS aircraft such as the Su-25. Rumors of the Yak-38 being deployed to Colorado are false; Numerous variants of the Yak-38 were developed, most notably the Yak-38M, which despite having improved engines and other components, was still a dog. There was also the Yak-38U, a serious contender for the title of 'Ugliest Airplane'. In the late 1970s, development of a successor to the Yak-38 began. This aircraft was the Yak-41 (Freestyle). The general configuration of the Yak-41 was similar to the Yak-38, with a pair of lift jets in the fuselage and a single main engine for thrust. However, its capabilities were massively improved. While the Yak-38 was a strictly subsonic aircraft, the Yak-41 was capable of supersonic flight, setting many records for VTOL aircraft (under the fictional designation Yak-141). Additionally, it incorporated far more advanced materials in its structure (including large scale use of composites), as well as improved avionics (such as a radar set which was actually useful). Its payload capacity, in terms of weight, was roughly the same as what the Yak-38 could (theoretically) carry. However, given that the Yak-41 was a dedicated air superiority craft, this was less of a concern than the Yak-38s payload deficiency in the strike role. Unfortunately for the Yak-41, it began testing in the late 1980s, just as the Soviet Union was falling apart. Though some testing continued through the early 90s, the Yak-41 never entered operational service. The second nail in the Yak-41s coffin was the Soviet Union / Russian Federation's acquisition of larger aircraft carrier(s), capable of operating aircraft such as the Su-27K and MiG-29K. Interestingly, for a few years in the early 1990s, Yakovlev collaborated with Lockheed Martin on the development of the Yak-41. This has given rise to many conspiracies about the F-35B being a clone of the Yak-41. While this is obviously false, it wouldn't be outside the realm of possibility that a few bits on the JSF might have drawn inspiration from Yak's design in some way. There was one final successor to the Yak-41; the Yak-43. An even more advanced evolution, the Yak-43 could have been quite capable (had it been built). From what I can find, it dispensed with the extraneous lift jets. Power would have been provided by a modified NK-32 turbofan, the same engine that powers the Tu-160. This would have given the Yak-43 significantly improved performance and payload capacity compared to its predecessors. Additionally, the Yak-43 would have incorporated low observability features into its design, bringing it closer to being a true competitor to aircraft such as the F-35B. In any case, the aircraft remained unbuilt, and I have not heard of any efforts to revive the design.
  10. Yakovlev MFI submission

    I found this interesting picture of the Yakovlev MFI design: Obviously, it was never built. The MiG submission was the 1.44 and the Sukhoi submission was the SU-47.
  11. On another website, i was recently provided with a link to this paper on Soviet mountain tactics and doctrine. I have not yet finished reading it, but it appears that it could be of interest to some here.
  12. The Manhattan Project gets all the glory(it deserves it), but the Soviets quickly developed their own atomic weapons. They had some help through espionage, but I think it might be another piece of McCarthyism to dismiss Soviet atomic scientists. Here is a post on the Nuclear Secrecy Blog on the early program. Good insight, but not the end-all-be-all of information on the subject. A Model of the First Lightning/Joe 1 bomb?
  13. Requires knowledge of Russian language and/or google translate. http://scilib.narod.ru/fleet.html
  14. Project 705

    The USSR's Project 705 class submarines incorporated many technological advances for their time. For instance, operation of the submarine was intended to be highly automated, reducing the total crew by a large amount. Additionally, it used large amounts of titanium in the hull, and a liquid metal cooled reactor, meaning that it could dive to much deeper depths and travel at higher speeds. In theory, the 705s should have been superior to any US Navy submarine design. However, they suffered from maintainence issues, were expensive to operate, and were exceptionally noisy, even compared to contemporary Soviet submarines. (via wikiped) I'm not very knowledgeable about naval matters, so I'm curious as to whether the 705's failings were the result of an inherently flawed concept behind their design, or because the Soviets at the time did not have the knowledge/technology to implement it properly.
  15. I want to show you several late Soviet MBT designs, which were created in 1980s in order to gain superiority over NATO focres. I do think that some of them are interesting, some of them look like a vehicle for Red Alert/Endwar games. Today, Russia is still use Soviet MBTs, like T-80 and T-72s, but in late 1970s and 1980s Soviet military and engineers were trying to look for other tank concepts and designs. T-64 and other MBTs, based on concept behind T-64, were starting to reaching their limits, mostly because of their small size and internal layout. PART 1 Object 292 We open our Box of Communism Spreading Godless Beasts with not so much crazy attempt to mate T-80 hull with 152 mm LP-83 gun (LP-83 does not mean Lenin Pride-83). It was called Object 292. First (and only, sadly) prototype was build in 1990, tested at Rzhevskiy proving ground (i live near it) in 1991, which it passed pretty well. Vehicle (well, turret) was developed by Leningrad Kirov factory design bureau (currently JSC "Spetstrans") Because of collapse of Soviet Union this project was abandoned. One of reasons was that main gun was "Burevestnik" design bureau creation, which collapsed shortly after USSR case to exist. It means that Gorbachyov killed this vehicle. Thanks, Gorbach! Currently this tank is localted in Kubinka, in running condition BTW. Main designer was Nikolay Popov. Object 292, as you see at photos, had a new turret. This turret could have been mounted on existing T-80 hulls without modifications to hull (Object 292 is just usual serial production T-80U with new turret, literally). New Mechanical autoloading mechanism was to be build for it. Turret had special Abrams-like bustle for ammunition, similar feature you can see on Ukrainian T-84-120 Yatagan MBT and, AFAIK, Oplot-BM. Engine was 1250 HP GTD-1250 T-80U engine. 152 mm main smoothbore gun was only a little bit bigger than 2A46 125 mm smoothbore gun, but it had much better overall perfomance. This prototype was clearly a transitory solution between so called "3" and "4th" generation tanks. Some nerd made a model of it: _________________________________________________________________________________________________________ ........Continue in Part 2
  16. UR-700: Father of Proton

    During the 1960s, there were many competiting designs for the rocket that would be used in the Soviet Lunar Program. Ultimately, the N1 was chosen, and proceeded to detonate and/or deflagrate vigorously on all four of its launches. One of the hypothetical competitors to the N1 was the UR-700. A development of Chelomei's 'Universal Rocket System' (which also included the UR-100, UR-200, and UR-500 (Proton)), there were several important differences between the UR-700 and N1. For one, while the N1 was to have used kerosene/LOX fuels, the UR-700 would have used hypergolics, namely UDMH/N2O4. This fuel combination has reduced specific impulse compared to cryogenic fuels. However, considering that Chelomei's other rockets in the series were developed as ICBMs fueled by hypergolics, it is easy to see why they would have been chosen for the UR-700. Additionally, while the N1 had no less than 30 first stage engines, the UR-700 first stage was to have been powered by only nine RD-270 engines. To be fair, the RD-270 was much larger than the NK-15 used on the N1. The UR-700 was planned to put 130-170 tons into LEO, which the Soviets judged to be the required amount for a direct ascent lunar mission. The choice of direct ascent, as compared to the lunar orbit rendezvous approach used by the Apollo missions (as well as Korolev's N1 based mission profile) results in a less efficient architecture. Most likely, Chelomei chose a direct ascent approach due to fears over the Soviet's lack of docking. Since the Americans had worked these issues out during the Gemini program, by the late 1960s, they were confident in the decision to use LOR. Given the numerous issues in the Soviet Lunar Program, it is unlikely that choosing the UR-700 over the N1 would have got a cosmonaut on the moon before Armstrong. However, it's an interesting what-if? Could the UR-700 have been modified for use in an LOR mission? I believe it could have, given the UR-series' modular nature. Of course, it is likely that the UR-700 would have run into many other unforeseen issues, which could have resulted in failure. I'm curious to see y'all's opinions on it.