| At the beginning
of the 1960s, internal rivalry marred the
efforts of the Soviet space industry to respond to the US challenge
to land a man on the Moon. Irreconcilable differences over the type of propellant
needed for the future "Moon rocket" divided key figures in the
Russian space program. Valentin Glushko, who held virtual monopoly on the
development or the rocket engines in the country, offered the propulsion
systems burning toxic self-igniting propellants for the giant N-1 rocket,
needed for the lunar expedition. However, Sergei Korolev, the chief-designer
of the N-1 rocket believed that the vehicle of this class should only employ
high-efficient and nontoxic cryogenic propellants.
As relationship between two men deteriorated, Korolev made a risky step of "enlisting" aviation-engine bureau led by Kuznetsov, as the provider of the propulsion systems for the booster stages of the N-1 launcher.
To enable the N-1 rocket to carry the manned lunar expedition, Korolev had to install 30 Kuznetsov's engines with the thrust of 150 tons on the first stage of the vehicle. When critics raised the issue of reliable performance of such large number of engines on the first stage, Glushko again proposed to replace Kuznetsov's engines with his own propulsion units capable of delivering as much as 640 tons of thrust each. Not surprisingly, Glushko's engines designated RD-270 would burn toxic propellants, and they were not acceptable for Korolev.
An independent government commission created to evaluate the matter sided with Korolev. In response, Glushko allied with Korolev's rival, Vladimir Chelomei, proposing an alternative rocket to the N-1 launcher. Designated UR-700, this monstrous rocket would make even Korolev's giant N-1 look small. Unlike Korolev's N-1, the UR-700 would employ modular design of the booster stages, which would allow to test and ship individual boosters of the vehicle separately.
Although Chelomei was apparently skeptical about Glushko's claims about insolvable problems in the development of the hydrogen-oxygen engines in the given time frame, he did agree to use Glushko's RD-270 engines on the UR-700 rocket. He hoped to overcome lower productivity of toxic propellants with more advanced performance characteristics of the vehicle itself.
The development of the UR-700 project apparently started around 1964. (87) In its original form, the first stage of the three-stage UR-700 rocket would consist of eight rocket stages, clustered around the second stage. Each booster was equipped with a single RD-270 engine. The second and third stage of the rocket used components developed for the UR-500 launcher. The first and second stages of the rocket would ignite at takeoff. (112)
The UR-700 would be capable of delivering a manned lander directly on the lunar surface bypassing the need for entering lunar orbit and consequent rendezvous between the lander and "a mother-ship" -- the scheme adopted for NASA's Apollo and Korolev's N-1/L-3 project. In the "package" with the UR-700 rocket, Vladimir Chelomei proposed his own lunar lander, initially designated LK-3.
Not surprisingly, Chelomei's alternative lunar plans drew considerable controversy. Critics pointed out that the work on the UR-700/LK-3 project would duplicate Korolev's efforts and would overload already limited resources of the Soviet Moon effort. The issue remained unsettled until 1965, when Chelomei's UR-500 rocket started flying. Around the same time, the problems Korolev faced with N-1 had became more apparent. Chelomei argued that the UR-500 has provided the first step toward the UR-700, which, in its turn could serve as a replacement for troubled N-1. (84) Along with Glushko, Chelomei managed to get support of such old Korolev's associates as Vladimir Barmin, the prime developer of launch equipment and V. Kuznetsov, the developer of the control systems.
On October 20, 1965, the minister of General Machine Building, MOM, S. A. Afanasiev gave a green light to the preliminary design of the UR-700 project. The giant rocket would use modified launch facilities of the N-1 rocket, which it meant to replace.
Korolev, who saw the UR-700 as a major hurdle for successful development of the N-1 rocket, drafted a desperate letter to S. A. Afanasiev pleading him to reconsider the issue. Letter claimed that Barmin's GSKB Spetsmash involves itself into the new project, while failing its work on the N-1 launch facilities. The same way, Korolev complained, Glushko's OKB-456 was wasting scarce government funds for unrealistic and environmentally dangerous propulsion systems, while his organization lacked good engines. According to RKK Energia's official historian, this letter, dated Nov. 10, 1965, has never been sent to Afanasiev, because Korolev concluded that the decision on the UR-700 development was made by the officials above MOM and his appeals to Afanasiev, the head of MOM, would not have any effect. (84)
In the second half of 1966, KBOM design bureau led by Vladimir Barmin started preliminary design of the launch facilities for the UR-700 rocket. KBOM bureau considered both the possibility of adopting the launch complex for the N-1 rocket for the purpose of launching the UR-700, as well as the development of the entirely new launch facility for the Chelomei's rocket.
At the end of 1966, the State Commission led by Academician M. V. Keldysh reviewed the preliminary designs completed by the contractors on the UR-700 project and recommended further research at the preliminary level.
The UR-700 project was not jump-started until the second half of 1967. On November 17, 1967, the Soviet government signed a decree No. 1070-363, approving a project code-named Galaktika (or Galaxy). It called for further development of the UR-700 project within one year. Chelomei reportedly had little hope for beating Americans to the Moon at that point. (87) At the time, the implementation of the UR-700 project was estimated in six-seven years. (78)
At the same time, the development of the RD-270 engine, the most crucial element of the UR-700 rocket, reached a testing stage. From October 1967 and until July 1969, Glushko's collective conducted 27 short-term test firings of 22 experimental versions of the RD-270 engines. Three engines fired twice and one engine was tested three times. In nine of these tests the engines performed flawlessly. (113)
According to the new configuration, the UR-700 rocket was now equipped with the six boosters on the first stage clustered on three axis around three boosters of the second stage. Each booster of both stages was equipped with a single RD-270 engine, which in combination with three engines of the second stage would generate 5,760 tons of thrust during the liftoff. The UR-700 would send LK-700 lunar lander for direct descent on the surface of the Moon.
The new design of the UR-700 matched the configuration of the flame ducts of the launch complex for the N-1 rocket. As result the facilities for the N-1 rocket in Baikonur could now be used for the launches of both N-1 and UR-700 rocket. However, the use of different propellants on the two vehicles still required the consideration of the entirely new launch complex for the UR-700. The resulting design of the launch complex developed by the Department 15 at KBOM featured two launch pads separated 1,500 meters from each other and the command post located 5,000 meters from the pads.
In 1969, as ill-fated N-1 finally reached the launch pad, the government shut down the competing UR-700 project. Instead, on June 30, 1969, Minister of General Machine Building, MOM, Afanasiev issued a decree No. 232, calling for Chelomei to conduct a preliminary design of the Martian expedition based on the UR-700M or UR-900 launch vehicle and the MK-700 spacecraft within one year.
A three-stage UR-700M rocket proposed by Chelomei for this project was expected to have a launch mass of 16,000 tons and its engines would develop 23,400 tons of thrust at liftoff. The vehicle would be able to deliver unprecedented 750 tons of payload into the low-Earth orbit. The launch complex for the rocket would include three autonomous launch pads. (112)
Chelomei also eyed the RD-270 engines for the project of the UR-900 rocket. The four-stage vehicle could be used for the Martian expedition. The elements of the UR-500 rocket would serve as the second, third and fourth stage of the rocket. The first stage of the UR-900 would be equipped with 15 RD-270 engines. The vehicle would be capable of delivering 240 tons to the low Earth orbit. (78)
Two versions of the UR-700 rocket and its transporter in comparison to a two-stage UR-500 (Proton) rocket (left), which served as the "upper stages" for the UR-700. Copyright © 2001 by Anatoly Zak
Scale models of the UR-700 launcher. Copyright © 2001 by Anatoly Zak
The RD-270 engine, intended for the first stage of the UR-700 rocket. Copyright © 2002 by Anatoly Zak