Searching for details:
The author of this page will appreciate comments, corrections and imagery related to the subject. Please contact Anatoly Zak.
Above: A three-stage Proton rocket moves to its launch pad in Baikonur in July 2000. This version of the vehicle launched Soviet Salyut space stations, the core module of the Mir space station and the Zvezda service module for the International Space Station.
No other launcher has played as many roles in the Russian space program as has the UR-500 rocket, known today as Proton. Conceived at the dawn of the space race as a "super-size" ICBM, the UR-500 became a major player in the race to the Moon in the mid-1960s. In the 1970s and 1980s, the four-stage version of the launch vehicle launched Soviet planetary probes toward the Moon, Mars and Venus and allowed the Soviet Union to place satellites into geostationary orbit. At the same time, three-stage Protons launched all Soviet space stations, as well as heavy transport ships and modules to expand and resupply them in space. In the 1990s, the Proton became the workhorse of Russia's commercial launch business.
Different versions of UR-500 (Proton) rocket:
The original UR-500 rocket (two booster stages):
The third stage
After initial three test launches, Proton was upgraded with a third stage in 1966, which became a standard part of the vehicle. It is currently powered by a single main engine -- RD-0213 -- and a RD-0124 steering engine. Both propulsion units were developed at KB Khimmash (KBKhA) design bureau in the city of Voronezh and mass produced by an adjacent mechanical plant.
The UR-500 (Proton) development cooperation:
The Proton-M, sometimes identified Proton-KM, featured several modifications, which were designed to increase the payload and reliability of the vehicle, compared to the previous version of the rocket, known as Proton-K. For the first time, a digital flight control system replaced traditional analog hardware onboard Proton. It allowed more efficient propellant consumption during the flight and, as a result, the delivery of bigger payloads into orbit. The rocket became even more powerful thanks to a new version of the RD-253 engines on its first stage. Moscow's Energomash development center increased the thrust of the engine from 151 to 160 tons. With these two improvements the Proton-M was able to deliver 22 tons of cargo into low Earth orbit compared to 20.7 tons for the standard Proton-K booster.
For missions beyond initial low orbits, the new Proton was equipped with a more advanced fourth stage called Briz-M. The new stage completed its inaugural flight onboard a regular Proton-K booster in May 2000, when it is delivered the Gorizont communications satellite. Briz-M takes much less space onboard the launch vehicle compared to its predecessor, the Block D upper stage, leaving the freed volume for cargo. As a result, the new payload shroud topping the rocket could offer 2.5 times more room for the satellites onboard Proton-M.
For a number of years, Khrunichev enterprise in Moscow, which builds the Proton rocket, hoped to introduce even more drastic changes in the Proton's design. KB Salyut, Khrunichev's development arm, planned a much more powerful upper stage than the Briz-M. Designated KVRB, it was to employ super-cold liquid hydrogen and liquid oxygen -- the same propellant used in the US Space Shuttle's main engines and in the Energia rocket. The development of a cryogenic stage initiated by Khrunichev in 1980s was stalled for years by Russia's financial problems. Work, however, has progressed somewhat during the first decade of the 21st century, thanks to commercial deals with India, which eyed similar technology for its own space launcher. KB Salyut has developed the cryogenic upper stage for the Indian government and hopes to use its off-the-shelf technology for the even bigger stage for Proton. KB Salyut representatives said that the Proton's cryogenic stage would house 18 tons of propellants compared to the 12 tons carried by the stage developed for the Indian rocket. With the new cryogenic stage, Proton would be able to compete with the Ariane-5 rocket, the most advanced European launcher, despite the geographical disadvantage of flying from Kazakhstan compared to Ariane's launch pad in equatorial region of French Guiana.
Lockheed Martin ends its partnership with Khrunichev
Published: 2006 Sept. 7
The American aerospace giant Lockheed Martin announced Thursday the sale of its stake in the International Launch Services, ILS, which has been marketing the Russian Proton rocket to commercial clients around the world. The move ended a more than decade-long partnership between Lockheed Martin and the Moscow-based Khrunichev enterprise, the Proton manufacturer. Despite this obvious setback to the commercial standing of Russia's workhorse launcher, the nation's Federal Space Agency, Roskosmos, attempted to put a positive spin on the event. The agency's press-release on the matter was entitled "Strengthening of International Positions of Khrunichev Enterprise." However many observers of the Russian space program saw Lockheed's decision as potentially damaging to the future projects at Khrunichev, including the development of the next-generation Angara rocket and the construction of its launch complex in Baikonur. In the past, Lockheed had promised to invest in the Angara project, which stalled for years due to the failure of the Russian government to fund it. Recently, Khrunichev's Proton and Rockot launchers each suffered a high-profile failure with a foreign payload, followed by a management shakeup at the company. Both vehicles successfully returned to flight during 2006.
In the first decade of the 21st century, developers planned a new series of upgrades to the Proton M rocket and its Briz-M upper stage to increase its payload to geostationary transfer orbits from 6,150 kilograms to 6,300 kilograms. Modifications to the Briz-M would enable it to fly so-called supersync missions, in which payloads are inserted into a supersynchronous orbit with an apogee of 65,000 kilometers or almost twice higher than the final altitude for a typical communications satellite. Such a trajectory on the way to a regular geostationary orbit would yield around 150-200 kilograms in extra payload mass. This is close to the payload capacity which was lost after Kazakhstan banned the launch path to the 48-degree parking orbit. The Kazakh government's decision to prohibit launches below the standard 51-degree parking orbit after 2009 was at least partially prompted by a JCSAT-11 launch failure, which resulted in debris crashing within 40-50 miles of the town of Dzhezkazgan. The first missions using supersync launch profile were scheduled for 2011, however not all satellites would be capable of supporting such flight sequences. As a result, Proton was expected to fly both types of missions.
Proton flight history
Early milestones in the Proton program:
1964 July 24: The first mockup of the UR-500 rocket arrived in Tyuratam for testing of the launch complex. The construction of the first launch pad (known today as "left" or Pad 23) for the UR-500 rocket in Area 81 was completed around this time.
1967 Sept. 29: A Proton rocket with a Block D upper stage failed to deliver a prototype of the L1 circumlunar spacecraft. The launch was not announced.
1967 Nov. 22: A Proton rocket with a Block D upper stage failed to deliver a prototype of the L1 circumlunar spacecraft after launch from the newly completed "right" launch pad (known today as Number 24) of Site 81 in Tyuratam. The launch was not announced.
1968 March 2: A Proton rocket with a Block D upper stage blasted off from the "left" launch pad at Site 81 in Tyuratam carrying a prototype of the L1 circumlunar spacecraft. It was announced as Zond-4.
1968 April 23: A Proton rocket with a Block D upper stage failed to deliver a prototype of the L1 circumlunar spacecraft after launch from the "right" launch pad at Site 81. The launch was not announced.
1968 July 14: An explosion at the Proton launch complex with a L-1 (Zond) spacecraft in pre-launch processing killed one person.
1968 Sept. 15: A Proton rocket with a Block D upper stage blasted off from the "left" launch pad at Site 81 in Tyuratam carrying a prototype of the L1 circumlunar spacecraft. It was announced as Zond-5.
Recent Proton missions in detail and their statistics:
*Success rate for the reported period since 2001
In-depth overview of recent missions:
Page author: Anatoly Zak; Last update: May 14, 2013
Page editor: Alain Chabot; Edit history: February 12, 2008; Feb. 6, Jan. 23, 2011
All rights reserved
Scale models used in dynamic testing illustrate the development history of the Proton rocket. Seen on the right is the early concept of the Proton rocket which would be comprised of four UR-200 missiles. The UR-200 can be seen separately on the left. The model in the center represents the final version of the UR-500 rocket. Copyright © 2001 Anatoly Zak
A decorative scale model of the UR-500 launcher apparently showing the early configuration of the booster designed to carry LK-1, a manned spacecraft for lunar flyby. OKB-52, the Proton developer, presented this model to its rival OKB-1, which was developing its own version of the circumlunar spacecraft. Ironically, it was OKB-1's L1 spacecraft for circumlunar mission, which ultimately rode the Proton into space, while LK-1 project was abandoned. Copyright © 2001 Anatoly Zak
Stills from the film footage, documenting the launch of the two-stage version of the UR-500 rocket. Credit: Khrunichev
The Proton rocket with the L1 spacecraft for circumlunar missions is poised for launch in Baikonur.
The concept of the UR-500LKS complex, designed to carry the LKS "mini-shuttle" into orbit. Credit: NPO Mash
The Proton rocket with the Zarya FGB control module is being erected on the launch pad in November 1998. Click to enlarge.
A scale model of the head section of the Proton rocket with Block D upper stage and a pair of Yamal satellites. Click to enlarge. Copyright © 2009 Anatoly Zak
The scale model of the Proton-M rocket with the KVRB hydrogen-powered upper stage. Copyright © 2001 Anatoly Zak
Comparison of Proton-K and Proton-M launch vehicles. Credit: ILS
Tail view of the Proton rocket shows its first stage with six external tanks and six main RD-253 engines. Copyright © 2000 Anatoly Zak
The 11D43 engine proposed by Valentin Glushko around 1960 for the first stage of the Proton rocket. It had low-expansion ratio and could be gimbaled to control the rocket in flight. Four such engines along with four 8D43 engines would be used on the first stage, if this configuration was ever approved. Copyright © 2000 Anatoly Zak
A full scale mockup of the RD-253 engine for the Proton's first stage. Copyright © 2002 Anatoly Zak
The RD-301 engine intended for the Proton's 11S813 fourth stage, which would burn a mix of liquid fluorine and ammiak! The combination, which has been under development since July 1969, was designed for the delivery of SNTV telecommunications satellite. The program of both the satellite and its upper stage was canceled in 1977. Copyright © 2002 Anatoly Zak