Notes on the History of Spaceflight, No 2. 1988 Mar 23 Revised 1988 Apr 2 Soviet Launch Vehicles - A Reassessment _______________________________________ Jonathan McDowell Harvard-Smithsonian Center for Astrophysics 60 Garden St, Cambridge, MA, 02138,USA Abstract The USSR has released new data on the reliability of its launch vehicles which force a reassessment of the identity of boosters used for some missions. I present an attempt to revise the assignments of boosters to payloads and present a revised listing of all Soviet orbital launches. This revised listing agrees with all the Soviet figures except those for the Kosmos carrier rocket. 1. Introduction Western observers have long attempted to guess which launch vehicles have been used for the various USSR satellite programs. Until recently very little Soviet data was made public, and since not even the names of the boosters were known various classification systems were set up. The fundamental work on the subject was the report to Congress by the late Charles Sheldon, Review of Soviet Space Programs, first issued in 1966. In recent years the DoD's "SL-" classification system has also been used to label the boosters, but observers have continued to rely on Sheldon's work as the guide to identifying the vehicle used for a given mission. The USSR has its own names for the rockets, which are often the same name as one of its major payloads. To distinguish between, for example, the Proton satellite and the Proton launch vehicle, the Soviets refer to the latter as the Raketa-Nosityel' (RN) Proton, or "Proton Carrier Rocket". The abbreviation RN is equivalent to the Western LV (Launch Vehicle). As part of the commercialization of the USSR's space fleet, more data has become available. The Mar 18,1988 issue of the magazine Aviation Week & Space Technology reports the first ever Soviet statistics on five of their launch vehicles and updates the figures for the Proton. Analysis of these data indicates the existence of a previously unsuspected booster, and alters a lot of the standard assumptions about which booster launched what payload. 2. The Soviet Launch Vehicle Fleet 2.1 The R-7 and its derivatives The world's first ICBM was the Korolev bureau's R-7 (NATO code SS-6 Sapwood). Used as a satellite launcher in 1957-8, it was known as the RN Sputnik; it is considered a 2-stage vehicle with the 4 strap-on boosters considered as one stage. It plays a role in the Soviet program analogous to the US Atlas first stage. The Soviets identify individual rocket stages with the designation "Blok" (module,stage) followed by a letter which seems to be assigned in (Cyrillic) alphabetical order; the central core is the Blok-A and the four strapons are Blok-B,V,G, and D. A Blok-E upper stage was added in 1958 to make the RN Vostok-L (Vostok carrier rocket, Lunar variant) and this stage was modified in 1960 to create the standard RN Vostok. In 1960 a four-stage vehicle was introduced for planetary missions, now known as the RN Molniya. This consists of an R-7 with a Blok-I third stage and a Blok-L fourth stage. Later, the R-7/Blok-I combination was used without the fourth stage. This configuration, known as the Soyuz, is the world's most used space launch vehicle. I argue in this paper that another variant may have been introduced in 1975, with an improved Blok-I stage. I will refer to this as the RN Soyuz II. 2.2 The Yangel Bureau rockets The Yangel burueau R-12 IRBM (NATO codename SS-4 Sandal) shot to world fame with a starring role in the Cuban Missile Crisis. It and the similar but larger R-14 (SS-5 Skean) IRBM have both been adapted (with an added upper stage) for space use, and are both referred to by the USSR as the Kosmos carrier rocket. I will refer to the R-12/upper stage as the RN Kosmos I and the R-14/upper stage as the RN Kosmos II. The Kosmos II upper stage is restartable to allow orbit circularization. The Yangel ICBM known in the West as the SS-9 Scarp (someone in the START negotiations must know its Soviet RS- designation, but it doesnt seem to have been published anywhere) was used in 1966-1971 to test orbital weapon techniques. Dummy warheads made a single orbit of the Earth before being deorbited over the target (in this case, in the USSR!). I suggest that for these flights, although entering orbit, the missile was considered as a strategic rocket rather than as a satellite launch vehicle. It was however adapted in 1967 as a satellite launch vehicle with an upper stage allowing it to orbit ocean surveillance and antisatellite weapon payloads. In 1977 it was somewhat modified for use as a replacement for the Kosmos II, taking over military applications and civilian science payloads. This variant is being commercialized by the USSR and is referred to as the Tsyklon (Cyclone) carrier rocket. Since it is believed to be very similar to the 1967 satellite variant, I will refer to the earlier variant as the RN Tsyklon I and the 1977 variant as the RN Tsyklon II. 2.3 Heavy launchers Two heavy launchers were developed for the Soviet counterpart to the Apollo program in the 1960s. The Chelomei bureau developed the Proton launch vehicle to test components and launch unpiloted lunar test missions. This vehicle, although plagued with launch failures until 1970, eventually became the standard Soviet heavy launcher. Since Soviet launch sites are at high latitude, the Proton is needed for all geostationary missions. There are two variants of the Proton in service, a 3-stage version used to launch Salyut class payloads, and the 4-stage version with a Blok-D or Blok-DM upper stage which is being commercialised. (There is no connection between the Blok-D Proton stage and the Blok-D R-7 strapon; perhaps the letters are assigned anew for each booster or by each different design bureau). The USSR has not released launch success data on the 3-stage variant. A 2-stage version was used for the initial test flights. I will distinguish these versions as RN Proton(2), Proton(3), and Proton(4). The second Lunar heavy launcher was a Saturn-V class booster with no known Soviet name. Known in the West as the 'G' or the 'TT-5', this immense rocket failed to reach orbit on all three of its test flights and was abandoned. The 1980's saw a new heavy launcher program reach fruition. The Energiya is a Space Shuttle class heavy lift vehicle with four or more liquid strap-on boosters and a large central core stage. It will be used to launch the Soviet Shuttle and 100-ton space station modules. The liquid rocket booster is used as a launch vehicle in its own right as a medium lift vehicle, known in the West as the SL-16. 2.4 Summary of the different designation systems RN Sheldon DoD Sputnik A SL-1 Vostok-L A-1 SL-2? Vostok A-1 SL-3 Molniya A-2-e SL-6 Soyuz A-2 SL-4 Soyuz II - - Kosmos I B-1 SL-7 Kosmos II C-1 SL-8 RS-? ("SS-9") F-1-r SS-9 Tsyklon I F-1-m SL-11 Tsyklon II F-2 SL-14 Proton(2) D SL-9 Proton(3) D-1 SL-13 Proton(4) D-1-E SL-12 ? ("G") G ? ? ("SL-16") - SL-16 Energiya - SL-W 3. The New Data The Soviet figures cover the period Jan 1,1970 to Jan 1, 1988 (except for the Soyuz booster where the period is 1972-1988 - maybe it failed a lot in 1971!). They give total successful launches to orbit and total failures to reach orbit, as follows: Vehicle Successes Failures RN Kosmos 317 14 RN Molniya 179 10 RN Tsyklon 61 2 RN Proton(4-st) 106 9 RN Vostok 88 1 RN Soyuz 554 12 (1972-1988 only) The figures for the 4-stage version of the Proton and the Mk II version of the Tsyklon agree exactly with Western tabulations. (The 3-stage Proton and the Mk I Tsyklon are not being offered for commercial use). There is however a problem with the Proton figures. It is clear from analysis of the rest of the data that upper stage failures which still leave the payload in orbit are counted as successes. However, only 7 failures to reach orbit have been admitted by the USSR up to 1986, and the only known failures since then are two missions which reached orbit but then had upper stage failures. I can't get 106 successes without counting these as successes. So I conclude that either (1) Proton(4) has had two further failures to reach orbit in 1986-7, or (2) US pressure to acknowledge the 1987 4th stage problems as failures has confused the Soviets enough that they have committed a clerical error and counted these missions as both successes and failures. Possibility (3), that two of the missions which have been assigned to the SL-16 are actually Proton launches, seems unlikely. However, some potential for confusion does exist as tracking evidence suggests the new Proton 4th stage may also be in use as the SL-16's upper stage. The Mk II Kosmos has 322 launches assigned to it in the period, so 5 must belong to some other booster. I suggest these launches may be either (1) the 4 Kapustin Yar suborbital spaceplane tests and the Kosmos-1578 mission, or (2) 5 of the ASAT targets, to be assigned to the Tsyklon I, or (3) bad arithmetic by the Soviets. The Mk I Kosmos was retired in 1977 and had 69 orbital launches in the period - it is not discussed by the Soviets. The Molniya has had 180 orbital launches in the period not 179 - but the Kosmos-1164 satellite was deorbited due to an upper stage firing in the wrong direction, so this is probably counted as a failure to reach orbit even though the Blok-I stage remained in orbit. The real problem comes with Vostok and Soyuz. The new encyclopedia Kosmonavtika SSSR by V. Glushko published a couple years ago confused the issue by attributing some types of Meteor weather satellite to both Vostok and Soyuz boosters in different parts of the book. We can only reconcile the Vostok numbers if all the Meteor type satellites, including the sun-synchronous launches, went on Vostoks. A further 11 launches previously attributed to Soyuz must also be Vostoks; most probably the last 11 second-generation spy satellites of the Kosmos-22 and Kosmos-120 series. This leaves 646 launches still attributed by Western totals to the Soyuz in the 1972-1988 period - according to the new Soviet figures, 92 of these must actually be using a different booster which is not any of the ones discussed above. Up to Jan 1,1988 I count 92 launches of the advanced 4th and 5th generation spy satellites (Kosmos-758,Kosmos-1246,Kosmos-1426 types) and civilian missions based on the same long-duration vehicle (Kosmos-1543 series), which I suspect is no coincidence. So I suggest that it is these launches which do not use the Soyuz booster. Since US intelligence has not reported the existence of this new booster (although the Pentagon document Soviet Military Power has accurately reported other new vehicles) I suggest that a *Mk II version of the Soyuz booster* has been introduced which is similar enough to Soyuz for the DoD not to count it as different, but sufficiently different (and has a sufficiently higher failure rate) that the Soviets have not included it in their totals. There remain a small number of payloads whose launch vehicle remains uncertain. The Polyot missions in 1963/4 are thought to be Vostok launched but I suspect they may have been the first uses of the Soyuz in its 3-stage form. The Kosmos-102 and Kosmos-125 payloads are mysterious. Although also assigned to Vostok, I wonder if they may be orbital tests of the later cancelled SS-10 ICBM/OBS system, as the timing is about right. 4. Success rate statistics 1970-1988 period statistics based on new Soviet data, the deductions discussed above, and study of orbital parameters to identify upper stage failures provides the following statistics. RN Total Launches % to orbit % to INTENDED orbit RN Kosmos 336? 95.8 94.9 RN Molniya 189 94.7 90.5 RN Tsyklon 63 96.8 95.2 RN Proton(4-st) 115 92.2 88.7 RN Vostok 89 98.9 97.8 RN Soyuz 618 (*) 97.9 (**) (*) Excluding launch failures in 1970-71. (**) Based on 72-88 figures only (566 launches, 12 failures to orbit, no partial failures). 5. The tables The tables contain complete known launch histories of all Soviet space launch vehicles. All orbital launches, all acknowledged launch failures, and most suspected launch failures discussed in the literature are included. Some of the more improbable rumours have been arbitrarily excluded. For details on Soviet launch failures, see 'Soviet Launch Failures' published privately by Phillip S. Clark, 17 Old Rd, Lee, London SE13 5QW, England. Column 1: A serial number is assigned to each successful orbital launch of the vehicle. Column 2: The Soviet name (if any) for the payload Column 3: An identification, representing my own attempt to classify the payload by mission and program. This classification forms part of a broader study of the USSR's space program and I will not discuss it here. Column 4: Launch site. KB= Kosmodrom Baykonur ("Tyuratam-Leninsk") PL= Kosmodrom Plesetsk ("Plesetsk","Northern Cosmodrome") KY= Kosmodrom Kapustin Yar (= Stantsiya Volgograd) This article and the accompanying tables are copyright (c) 1988 Jonathan McDowell. Unauthorized reproduction is prohibited. Note: since the original release of this note I have reassigned Kosmos-1079 and Kosmos-1152 as 4th generation Recon H missions using the Soyuz II booster, since despite their short lives they released no orbital debris. I have also reassigned Kosmos-1882 and Kosmos-1906 (and this year's K-1920) as third generation type missions since they did produce orbital debris, and their 20-day operational lifetimes have been demonstrated by Vostok class satellites in the biosat series. They therefore used the Soyuz booster and so the overall totals for the 1972-1988 period are unchanged.