The Zenit-3SL was an

expendable ''Expendable'' is a science fiction novel by the Canadian author James Alan Gardner, published in 1997 by HarperCollins Publishers under its various imprints.Avon Books; HarperCollins Canada; SFBC/AvoNova. Paperback edition 1997, Eos Books. It i ...

carrier rocket A launch vehicle is typically a rocket-powered vehicle designed to carry a payload (a crewed spacecraft or satellites) from Earth's surface or lower atmosphere to outer space. The most common form is the ballistic missile-shaped multistag ...

operated by

Sea Launch Sea Launch was a multinational—Norway, Russia, Ukraine, United States—spacecraft launch company founded in 1995 that provided orbital launch services from 1999 to 2014. The company used a mobile maritime launch platform for equatorial l ...

. First flown in 1999, it was launched 36 times, with three failures and one partial failure. It was a member of the Zenit family of rockets, and is built by the

Yuzhnoye Design Bureau The ''Pivdenne'' Design Office (), located in Dnipro, Ukraine, is a designer of satellites and rockets, and formerly of Soviet intercontinental ballistic missiles (ICBMs), established by Mikhail Yangel. During the Soviet era, the bureau's OKB de ...

. RKK Energia produced the

Block DM-SL Blok 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 rockets . By 2002 its modification Bl ...

upper stage A multistage rocket or step rocket is a launch vehicle that uses two or more rocket ''stages'', each of which contains its own Rocket engine, engines and Rocket propellant, propellant. A ''tandem'' or ''serial'' stage is mounted on top of anoth ...

, whilst the

payload fairing A payload fairing or nose fairing is a nose cone used to protect a launch vehicle, spacecraft payload (air and space craft), payload against the impact of dynamic pressure and aerodynamic heating during launch through an atmosphere. An additiona ...

was produced by

Boeing The Boeing Company, or simply Boeing (), is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support s ...

. Launches were conducted from the

Ocean Odyssey LP ''Odyssey'' is a self-propelled semi-submersible mobile spacecraft launch platform converted from a mobile Oil platform, drilling rig in 1997. The vessel was used by Sea Launch for equatorial Pacific Ocean launches. She works in concert with ...

platform anchored on the

equator The equator is the circle of latitude that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern Hemispheres of Earth, hemispheres. It is an imaginary line located at 0 degrees latitude, about in circumferen ...

in the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

, at a point with 154°W

longitude Longitude (, ) is a geographic coordinate that specifies the east- west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek lett ...

, about 370 kilometres east of

Kiritimati Kiritimati (), also known as Christmas Island, is a Pacific Ocean atoll in the northern Line Islands. It is part of the Republic of Kiribati. The name is derived from the English word "Christmas" written in Gilbertese according to its phonol ...

. The Zenit-3SL design began in the late 1980s as the Zenit-3, a proposed replacement for the

Proton-K The Proton-K, also designated Proton 8K82K after its GRAU index or SL-12 after its model number, was a Russian, previously Soviet, carrier rocket derived from the earlier Proton. It was built by Khrunichev, and launched from sites 81/23, 8 ...

, which would have used a

Zenit-2 The Zenit-2 was a Ukrainian, previously Soviet, expendable carrier rocket. First flown in 1985, it has been launched 37 times, with 6 failures. It is a member of the Zenit family of rockets and was designed by the Yuzhmash. History With 13� ...

rocket with a

Block D Blok 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 rockets . By 2002 its modification B ...

upper stage. This proposal was shelved after the dissolution of the

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

, as Russia inherited the space programme, however the Zenit was manufactured in

Ukrainian SSR The Ukrainian Soviet Socialist Republic, abbreviated as the Ukrainian SSR, UkrSSR, and also known as Soviet Ukraine or just Ukraine, was one of the Republics of the Soviet Union, constituent republics of the Soviet Union from 1922 until 1991. ...

. Boeing became involved in the programme in 1994. The design was subsequently modified, with a modified version of the Block DM replacing the Block D. Sea Launch integrated the rockets in

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, and transfers them to Odyssey via the '' Sea Launch Commander'' for transportation to the launch site. Once at the launch site, the rocket was erected on the platform, and a three-day countdown was initiated. The countdown was fully automated, and personnel were evacuated from the launch platform to ''Commander'' prior to launch. Zenit-3SL launches predominantly carried

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...

s into

geosynchronous transfer orbit In space mission design, a geostationary transfer orbit (GTO) or geosynchronous transfer orbit is a highly elliptical type of geocentric orbit, usually with a perigee as low as low Earth orbit (LEO) and an apogee as high as geostationary orbit ...

s. As of 2009, the only payload to be launched by a Zenit-3SL that was not a communications satellite was a DemoSat, on the maiden flight. The only launch to be conducted to an orbit other than GTO was that of ICO F-1, which was intended to be placed into

medium Earth orbit A medium Earth orbit (MEO) is an geocentric orbit, Earth-centered orbit with an altitude above a low Earth orbit (LEO) and below a high Earth orbit (HEO) – between above sea level.

, however the rocket failed to reach orbit.

Reliability

Of thirty-six rockets launched, three failed, with a fourth placing its payload into an incorrect, but recoverable orbit. The first failure occurred during the third flight, on 12 March 2000, when a software error resulted in the premature cutoff of the second stage, leaving the ICO F-1 satellite unable to reach orbit. On 29 June 2004, during the launch of Apstar 5, the upper stage shut down 54 seconds early due to a wiring fault, leaving the satellite in a lower than planned orbit. The spacecraft raised itself to the correct orbit by means of its onboard manoeuvring engines, at the expense of fuel intended for stationkeeping once in the correct

orbit In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...

. On 30 January 2007, a Zenit-3SL exploded on the launch pad after an engine failure caused by debris in the

turbopump A turbopump is a fluid pump with two main components: a rotodynamic pump and a driving gas turbine, usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The most co ...

. The payload on that flight was the

NSS-8 NSS-8 was a Dutch telecommunications satellite that was destroyed during launch. It was a Boeing 702 spacecraft with 56 C-band and 36 Ku-band transponders, and it was part of the SES NEW SKIES. The satellite, which was insured, was destroyed ...

for SES New Skies. This caused a considerable amount of downtime whilst damage to the launch platform was repaired. On 1 February 2013, during the launch of Intelsat-27, a Zenit-3SL launch vehicle suffered a premature engine shutdown, as the rocket strayed from its lift-off trajectory, plunging into the Pacific Ocean shortly after launch.

References

{{expendable launch systems Zenit (rocket family) Vehicles introduced in 1999

Reliability

See also

References