*******************************************************************<\/p>\n
PRESENT DAY SOVIET LAUNCH VEHICLES<\/p>\n
Although most observers of the exploration of space are quite familiar
\nwith the various US launch vehicle families (Atlas, Titan, & Saturn),
\ntheir Soviet counterparts are still a mystery to most Western analysts.
\nThis shroud of secrecy is encouraged by the Soviet government which, for
\nvarious reasons, has released little information on these launch
\nvehicles. However, given the few tidbits of data available from news
\nphotos, orbital elements, and the rare Soviet publication, it is now
\npossible to describe the history and capability of the Soviet present
\narsenal.
\n The following is a summary of the known major Soviet rocket engines and
\ntheir major characteristics. (Vacuum thrust is given in metric tons). <\/p>\n
Number of Vacuum Chamber Specific Principal
\nName Chambers Thrust Pressure Impulse Propellents Use
\n————————————————————————
\nRD-100 1 30 234 Alcohol\/LOX R-1
\nRD-103 1 55 28 245 Alcohol\/LOX SS-3
\nRD-107 4 102 60 314 RP-1\/LOX A Class
\nRD-108 4 96 52 315 RP-1\/LOX A Class
\nRD-111 4 166 80 317 RP-1\/LOX SS-10??
\nRD-119 1 11 80 352 UDMH\/LOX B Class
\nRD-214 4 74 45 264 RP-1\/Nitric Acid B Class
\nRD-216 4 177 75 290 UDMH\/Nitric Acid C Class
\nRD-219 2 90 75 293 UDMH\/Nitric Acid SS-9??
\nRD-253 1 ? 400 ? UDMH\/N2O4 D Class<\/p>\n
As is well known, the Soviets began rocket research on their own
\nbefore the Second World War. The first liquid fueled engine developed
\nby Gird, an amateur rocket club, was called the ORM-1, and had the
\ndistinction of being able to use both cryogenic and storable fuels, an
\nability the Soviets utilized in later vehicles. This small program was
\ngreatly aided by the capture of German V-2 rockets and scientists in
\n1945. The Soviets, as did the US, gained much experience studying the
\nGerman effort. The first post-war Soviet rocket, the R-1, a V-2 clone,
\nwas launched in 1947, and was powered by the RD-100 engine, the first in
\na long line of large German-influenced engines. In the early 1950’s,
\nthe Soviets developed the Shyster vehicle (dubbed the SS-3 by the US Air
\nForce), basically an improved copy of the V-2, for testing Soviet-built
\ncomponents in ballistic flights. During this period, the Soviet
\ngovernment decided that in order to send 10,000 lb. atomic bombs to the
\nUS mainland, it would be necessary to develop a large booster, with much
\ngreater capacity than the Shyster. Thus, Soviet scientists developed
\nthe techniques of clustering and parallel staging simultaneously. This
\nentailed the use of a single turbo-pump per cluster, which led to the
\nSoviets adopting a distinct definition of an engine from the Americans.
\nThe single 50,000 lb thrust engine of the V-2 was clustered in groups of
\n4, with a single set of turbopumps for each group. The core cluster of
\n4 (called the RD-108 engine, although it used 4 combustion chambers and
\n4 exit nozzles) was surrounded by 4 strap-on clusters (the RD-107, but
\nbasically identical to the RD-108), for a total of 20 first stage
\nengines. After the vehicle left the lower atmosphere, the four
\nstrap-ons were jettisoned, and the core cluster was to carry the warhead
\non a ballistic flight to the US. This vehicle, known to the Air Force
\nas the SS-6, and referred to as the A-class launcher by the Library of
\nCongress classification system, became the first Soviet satellite
\nbooster, launching Sputnik in 1957. With a single 12,000 lb thrust
\nengine added as an orbital stage, the A class booster was used to launch
\nthe Vostok capsule. In the mid 1960’s, a four chambered, LOX\/RP1 fueled
\nengine was developed by the design bureau of the late C.A. Kosberg.
\nThis 50,000+ lb. thrust engine replaced the earlier orbital stage on the
\nSoyuz booster.
\n Soon after the conception of the A class vehicle, the development of
\nthe hydrogen bomb enabled much smaller warheads to be built, making the
\nlarge booster obsolete soon after its first launch. The core cluster
\nwas immediately reconfigured into a missile in its own right, with the
\nengine now dubbed the RD-214. In order to decrease launch preparation
\ntime, the Soviets converted the engine to use storable propellents,
\nnitric acid and kerosene, (as in the pre-war ORM-1). This combination
\nis much less efficient than the RD-107\/108’s LOX\/RP-1 fuel, resulting in
\na lowered thrust of about 150,000 lbs for the RD-214. The new launcher,
\nwas deployed in Cuba and Eastern Europe as an intermediate range
\nballistic missile and was dubbed as the SS-4 by the US Air Force.
\nTopped by an orbital stage, the hydrazine fueled 24,000 lb thrust RD-119
\nengine, this launcher, known as the B class vehicle, is the equivalent
\nof of the US Thor\/Delta.
\n The RD-214 engine was later refined by the use of UDMH instead of
\nkerosene for fuel. This new storable fuel increased specific impulse
\nfor the engine from 264 to 290 seconds. Thrust was increased to 380,000
\nlbs. through increase in chamber pressure from 45 to 75 atmospheres.
\nThe engine was renamed the RD-216, and was installed in the first stage
\nof the C class booster. This new vehicle, the equivalent of the Atlas
\nlauncher, replaced the earlier B class vehicle, and is now the third
\nmost used space launcher in the world.
\n The primitive SS-6 ICBM was ineffective as a weapon. The Soviet
\nUnion, faced with the need for a storable ICBM, developed a new missile.
\nThe result was the SS-9, a 2 stage ICBM with 6 thrust chambers, using a
\ncommon turbopump, for the first stage. It is reasonable to suppose that
\nthe tried and true V-2 design was again used in this new configuration
\nwith hypergolic fuels for quick launch reaction and storability. It can
\nbe expected that first stage thrust is greater than the 300,000 lbs that
\nthe original LOX\/Kerosene combination would have produced, due to higher
\nefficiency of the Hydrazine\/UDMH fuel and Nitrogen tetroxide oxidizer,
\nand advances in turbopump technology that the Soviets can be expected to
\nhave achieved in the 8 year period between the introductions of the A
\nclass and the F class vehicles. The F class vehicle is roughly
\nequivalent to the US Titan missile in payload capacity.
\n The Soviets felt that the need existed for a larger space payload than
\nthe A class, which was limited to 14,000 lbs. in low orbit, could
\nprovide. A new engine, the RD-253, was developed. One of these engines
\nwas used in the air-launched core vehicle for the new Proton vehicle,
\nwith six RD-253 strap-ons as the first stage, giving a total thrust of
\n2.5 to 3 million lbs., and a payload capacity of 40,000 lbs. in orbit.
\nDetails on the upper stage of the Proton are lacking, but it is possible
\nto provisionally state that the RD-219 could be a candidate. As the
\nRD-219 is claimed to be a second stage engine, with thrust of almost
\n200,000 lbs, a probable application for this engine is as the second
\nstage of the Proton, if one considers the external strap-ons as a zero
\nstage. The tentative configuration of the Proton is thus:<\/p>\n
Zero stage (6 strap-on RD-253) 3,000,000 lbs (approx)
\n 1st stage (one cluster) 500,000 lbs (approx)
\n RD-219 2nd stage 180,000 lbs<\/p>\n
The Proton rocket is used to launch the Salyut space station, as well as
\nheavy military payloads.
\n It is well known that the Soviets maintain a heavy launch schedule.
\nGiven the serial production of many thousands of the V-2 class engines,
\nwhich entailed little developmental costs (thanks to the Germans), it is
\nreasonable to assume that great economies of scale prevail in their
\nspace effort. Whereas the US will spend hundreds of millions to develop
\na launch stage that may be used less than ten times (as with the Centaur
\nG stage), the USSR has spent little on a family of boosters that
\napparently utilize the same engine design. The U.S. at the beginning of
\nthe Space Age also developed several boosters from a single engine
\ndesign, the H-1, which grew from 135,000 lbs to 205,000 over twenty
\nyears. However, the H-1 family was soon superceded by many more
\npowerful and more efficient designs, and is now far from being the
\nleading edge of engine technology in the U.S. Apparently, the Soviets
\nhave been content to stay with their basic original design, which has
\ngrown from less than 40,000 lbs to now over 500,000 lbs of thrust. This
\nsame paucity of engine research could explain the mysterious lack of a
\nliquid hydrogen engine in the Soviet arsenal. Although payload size
\ncould be greatly increased with even the smallest of cryogenic stages,
\nthe Soviets are apparently willing to forego the developmental costs in
\nfavor of keeping program costs to a minimum. Given this low priority
\nfor engine research, rumors of several new Russian launch vehicles seem
\nunfounded, as all of the rumors presuppose Soviet development of liquid
\nhydrogen engines that surpass US engines in efficiency. Given the
\npresent advantage in engine R & D by the US over the Russians, it would
\nbe highly doubtful that the Soviets will surpass us in engine technology
\nin the near term. Making these rumors more dubious is the fact that
\npresent Soviet launch vehicles can launch all payloads that the Soviets
\nhave announced for the foreseeable future, including the 1993 asteroid
\nflyby. Thus, one can probably count on seeing (or reading about) the
\npresent group of Soviet vehicles for many years to come.
\n*************************************************************************
\nMany thanks to Anthony Kenden, Art Bozlee, C.P. Vick, V.P. Glushko,
\nKenneth Gatland, John Parfitt, and many others for their published work
\nand their criticism of my earlier entry. Please feel free to correct
\nany factual errors that I may have made in this entry, so they may be
\ncorrected.<\/p>\n
