Zond program Zond (russian: Зонд, lit=probe) was the name given to two distinct series of Soviet robotic spacecraft launched between 1964 and 1970. The first series, based on the 3MV planetary probe, was intended to gather information about nearby plan ...

(Зонд; Russian for "probe") was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...

robotic spacecraft program launched between 1964 and 1970, using two spacecraft series, one for interplanetary exploration, and the other for lunar exploration.

Program details

The program had two series of spacecraft. The first series, based on the 3MV planetary probe, was intended to gather information about nearby planets. The second series of test spacecraft were intended as a precursor to crewed circumlunar loop flights, using a stripped-down variant of Soyuz spacecraft, consisting of the service and descent modules, but lacking the

orbital module The orbital module is a compartment of some space capsules used only in orbit. It is separated from the crewed reentry capsule before reentry. The orbital module provides 'habitat' space to use in orbit, while the reentry capsule tends to be focu ...

The

Government of the Soviet Union The Government of the Soviet Union ( rus, Прави́тельство СССР, p=prɐˈvʲitʲɪlʲstvə ɛs ɛs ɛs ˈɛr, r=Pravítelstvo SSSR, lang=no), formally the All-Union Government of the Union of Soviet Socialist Republics, commonly ab ...

had suppressed failed

Space Race The Space Race was a 20th-century competition between two Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the t ...

missions information to prevent bad publicity during the height of the Cold War and the Space Race. Since the

fall of the Soviet Union The dissolution of the Soviet Union, also negatively connoted as rus, Разва́л Сове́тского Сою́за, r=Razvál Sovétskogo Soyúza, ''Ruining of the Soviet Union''. was the process of internal disintegration within the Sov ...

in 1991, much previously restricted information became available.

Zond 1964A

Zond 1964A a SL-6/A-2-e launch vehicle launched 4 June 1964, failed to achieve

Earth orbit Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi) in a counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes days (1 sidereal year), during which time Eart ...

. The problem was found to be a faulty valve, that failed 104 seconds after launch. The payload was Molniya-1 No.2, a Soviet communications satellite.

Zond 1967A

Zond 1967A was launched on 28 September 1967. The Soyuz 7K-L1 No.4L s/n 4 craft was 5,200 kg. Sixty seconds after launch the rocket veered off course. The

escape tower A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, suc ...

took the Zond capsule safely away from the falling rocket. The rocket crashed 65 km downrange and ended the attempted Lunar flyby. The SL-12/D-1-e Proton launcher first stage had six engines. It has found that a fuel line of one engine was blocked by a rubber plug which had come loose. Had the mission been successful this would have been designated Zond 4.

Zond 1967B

Zond 1967B launched on 22 November 1967 in an attempted Lunar flyby mission. The Soyuz 7K-L1 No.5L craft was 5,200 kg. A second stage failure occurred and the launch vehicle crashed 300 km downrange. The automatic system shutdown the other engines. The Zond capsule separated with the escape tower and was safely recovered. Had the mission been successful this would also have been designated Zond 4.

Zond 1968A

Zond 1968A was launched on 23 April 1968. The Zond was on a Soyuz 7K-L1 s/n 7L. The craft was 5,600kg. The

Proton K The Proton-K, also designated Proton 8K82K after its GRAU index or SL-12 after its model number, 8K82K, was a Russian, previously Soviet Union, Soviet, launch vehicle, carrier rocket derived from the earlier Proton (rocket), Proton. It was built ...

rocket exploded 4 minutes and 30 seconds after launch. Had the mission been successful this would also have been designated as Zond 5. The second stage rocket failed 260 seconds after launch. Another attempted Lunar flyby. The fault was found to be a short circuit in the control system that caused engine 2 of the SL-12/D-1-e second stage to shut down.

Zond 1968B

Zond 1968B was planned to be launched on 21 July 1968 on a Soyuz 7K-L1 s/n 8L. On 14 July, while preparing for launch, the

Blok D Blok D (russian: Блок Д meaning Block D) is an upper stage used on Soviet and later Russian expendable launch systems, including the N1, Proton-K and Zenit. The stage (and its derivatives) has been included in more than 320 launched r ...

(second-stage) rocket exploded. The launchpad explosion killed three workers. The Proton first-stage booster rocket and the Zond spacecraft had only minor damage. Had the mission been successful this would have been designated Zond 7.

Zond 1969A

Zond 1969A was launched on 20 January 1969, a

Soyuz 7K-L1 s/n 13 Soyuz is a transliteration of the Cyrillic text Союз ( Russian and Ukrainian, 'Union'). It can refer to any union, such as a trade union (''profsoyuz'') or the Union of Soviet Socialist Republics (Сою́з Сове́тских Социалис ...

, was to be a lunar flyby and return to

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

with pictures. One engine of the SL-12/D-1-e second stage shut down 25 seconds early. This put the craft into an emergency system shutdown and aborted the flight. The escape tower fired and the Zond craft was returned to Earth safely. Had the mission been successful this would have been designated as Zond 7. The craft was 5,600 kg.

Zond L1S-1

Zond L1S-1 Zond L1S-1 was a Zond capsule to be placed into orbit around the Moon by the first launch of the N1, a Soviet made super heavy-lift launch vehicle designed to land manned Soviet spacecraft on the Moon. The Zond capsule was equipped with a dum ...

failed on 21 February 1969, this was the first launch of the

N-1 rocket The N1/L3 (from , "Carrier Rocket"; Cyrillic: Н1) was a super heavy-lift launch vehicle intended to deliver payloads beyond low Earth orbit. The N1 was the Soviet counterpart to the US Saturn V and was intended to enable crewed travel to the ...

, a super heavy-lift launch vehicle built to send a crewed Soviet

spacecraft A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, p ...

to the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

, like the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

Apollo program. Just 66 seconds after liftoff the engine's turbopumps exploded.

Zond L1S-2

The Zond L1S-2 (Zond-M 2) mission was to be the second test of the N-1 rocket engine, moded SL-15/N-1. Zond L1S-1, the first test N-1 rocket, had failed on 21 February 1969. L1S-2 - Zond-M 2 had a Zond capsule with Moon landing site cameras and a test Soviet Moon lander. L1S-2 goal was to put the lander into lunar orbit. Zond L1S-2 launched on 3 July 1969 at 23:18:32 Moscow time. A few seconds after liftoff, with the rocket at an altitude of about 180 meters, the main engines shut down. The powerful N-1 rocket crashed back on to launchpad and exploded 18 seconds after liftoff. The massive explosion destroyed Pad 110 East (110/38) at the Baikonur Cosmodrome. The Zond escape tower fired and the capsule landed clear of launchpad, about 1 km away. It was determined that engine 8's oxygen pump had failed and exploded. The explosion damaged the engine, which started an automatic shutdown of all the other engines. Two more subsequent tests of the N1 rocket failed: Soyuz 7K-L1E No.1 and Soyuz 7K-LOK No.1. With these four failures, the N-1 manned lunar program was canceled. NASA used the

Saturn V Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with three stages, and powered with liquid fuel. It was flown from 196 ...

rocket for lunar missions, a super lift rocket like the N-1.

Cosmos 154

* Cosmos 154 failed to go into the planned translunar trajectory. The craft was 5,600 kg. Cosmos 154 was one of the first Zond attempts.

Zond 3MV-1 No.2

Zond 3MV-1 No.2 launched 19 February 1964, exploded on the pad.

References

{{Inspace Missions to the Moon Zond program Lunar flybys