Zenit (rocket family)

The zenith [ ze ː nɪt ] (Ukrainian Зеніт; Russian Зенит ) is a Ukrainian carrier rocket and was originally developed in the years 1976 to 1985 as the first stage of the Energia rocket - in a single-stage variant as a booster with the name Zenit- 1 -, but came at the same time like this, equipped with a high school, as an independent carrier rocket used.

It is mostly manufactured in Dnepropetrovsk in Ukraine and is therefore considered by the collapse of the Soviet Union as the Ukrainian, while some key components, such as the first-stage engines are manufactured in Russia. It is used today by Russia to launch military and Earth observation satellites, but is to be replaced in the future by the purely Russian Angara rocket.

Zenit is the most technologically advanced launcher, which is Russia and Ukraine are available. Also it is considered as one of the world's most modern, so use the new U.S. Atlas rockets derived from the zenith RD -180 main engine.

Zenit- 2

A two-stage version of the Zenit, developed by the design bureau in Dnepropetrovsk Yuzhnoye is also known as Zenit- 2 ( GRAU index 11K77 ). It is in the power range of the Soyuz with 7 tons in low-Earth orbit and the proton with 21 t at around 13.7 t ( Baikonur launch site ). The first launch took place on 13 April 1985, the rocket is still in service. Zenit- 2 is 57 m high and has a diameter of 3.9 m, is the take-off mass about 460 t. The first stage uses a four combustion chambers equipped with RD -171 engine, which develops a thrust of 7259 kN at the bottom, making it the strongest ever built rocket engine. RD -171 surpasses its specifications, even the F-1 main engine of the American Saturn V moon rocket. A version with two combustion chambers is used as a feed weaker RD -180 engine in the American Atlas III and Atlas V rockets use a version with a combustion chamber RD - 191 in the future Angara rocket. When used as boosters of the Energia Zenit received a verfügendes have less control than RD -171 RD -170 engine, which should be used several times also, since the booster should be salvaged and reused. The second stage of the Zenit uses the RD -120 ( not to be confused with the RD -0120 the Energia ) as the main engine and four RD -8 engines for attitude control. The first and second stages are both working with liquid oxygen (LOX ) and kerosene - type RP -1. The zenith was the first Soviet rocket, an adaptive control system based on occurring disturbances (eg wind ) reacts in flight and can be reprogrammed from the ground.

After their first inserts the zenith should replace the Soyuz rocket in manned space flight. You should be newly developed spaceship Sarja (not to be confused with the module of the ISS ), the 15 t was heavy and could accommodate up to eight astronauts carrying into orbit. In Baikonur towers were built to the entrance of cosmonauts in the rocket, but they came after the collapse of the Soviet Union never used. The development of the space ship was stopped in 1989 in a very early stage. A Zenit- launch facility in Plesetsk was also never completed for lack of money. For several years starting system in Plesetsk will be rebuilt for the start of future Angara rockets.

Of the 37 previously inserts the Zenit- 2 were only 28 fully successful (as of July 2007). This is mainly due to the very complex technology of the zenith. The most serious accident occurred on October 4, 1990, when a Zenit- 2 exploded three seconds after the start, while one of the two launch pads completely destroyed. The money for the reconstruction of the plant lacked, however, so that at present only a working launch pad at Baikonur exists. Your first and only commercial use had the Zenit- 2 on 9 September 1998, as it should carry 12 Globalstar satellites into space. But the second stage of the rocket failed, whereupon it crashed along with the expensive delivery after a few minutes of flying on the ground.

In June 2007, the first launch of the modified Zenit- 2M was (some even official sources still use the term Zenit- 2). With this launch, the rocket from Baikonur brought a military payload into low-Earth orbit. Zenit- 2M takes some built as early as the Zenit- 3SL modifications, such as the control system upgrade. The first stage main engines were modified and will now deliver more thrust, this now carry the designation RD- 171M. The commercial version of two-stage Zenit- 2M is marketed since 2007 under the name Zenit- 2SLB within the land -launch project for launch from Baikonur, but it has been so far (as of October 2012) carried out no start.

Zenit- 3

Zenit- 3 is a three-step execution of the zenith, which is used for launching of satellites into geostationary transfer orbit ( GTO). The company Sea Launch uses the three-stage Zenit- 3SL rocket, with the abbreviation SL stands for Sea Launch. As a starting place, a floating drilling rig converted is used, which refers to the starting position near Kiritimati. Due to the proximity of the launch site to the equator, the payload capacity of the rocket increases compared to Baikonur, so that a Zenit- 3SL up to 6 ton satellite into Geotransferorbit can bring. The first two stages of the rocket are identical except for some minor modifications to those of a zenith -2. As a third step, the built by the Russian company RKK Energia Block DM -SL is used, based on the Blok DM of the Proton rocket, but with LOX / kerosene used other fuels. The payload capacity of the geostationary transfer orbit was initially 5250 kg and could be improved by some modifications to 6066 kg. In this case, engines were modified (especially the engine block of the DM -SL), increases Treibstoffzuladung all three levels and simultaneously reduce the unladen mass of the steps. The new missile (without the third stage) is also often called the zenith -2S.

The first flight of the Zenit- 3SL with a dummy satellite took place March 28, 1999, the first commercial flight was followed in the same year. Zenit- 3SL Total so far completed 30 missions, with two launches failed and a start is considered a partial success ( the third stage did not reach the planned orbit, but the satellite with their own engines could reach the orbit ). Since the launch site outside the CIS is, the starts are not subject to CoCom regulations. It is estimated that the launch of a Zenit- 3SL costs the customer around 90 million U.S. dollars.

At the start the NSS -8 communications satellite test on 30 January 2007, a Zenit- 3SL exploded launcher directly to the " Odyssey " launch platform. The platform thereby suffered limited damage and was already on 1 February 2007 again with the full crew mans, who had retired as usual during the launch of the " Sea Launch Commander". The cause of the explosion, a metal part in a fuel pump could be determined. On 15 January 2008, the first launch took place after the disaster with the telecommunications satellite Thuraya 3, which was successful.

Under the name Land Launch to bring a three-stage Zenit- 3SLB from Baikonur satellite into geostationary transfer orbit ( GTO). For this, the Zenit- 3SL is slightly modified (the first two levels then correspond to the Zenit- 2M) and started from the Zenit -2 launch system. Due to the favorable location of the cosmodrome Baikonur rocket can carry only 3.6 tonnes to GTO. The advantage of the country launches, however, is that the start up costs are much lower than at a start of the lake. The first launch of the Land Launch Zenit- 3SLB was scheduled in April 2007 to the end of 2007 with a commercial communications satellite.

Another three-step execution of the zenith is to use the Fregat -SB upper stage instead of the Block DM- SL. The level is derived from the Fregat used on Soyuz rockets, but has additional droppable fuel tanks. You can thus take up more fuel and carry heavier payloads into high orbit. This version of the Zenit is flown from Baikonur, but was not marketed by Land Launch. The rocket was launched on 20 January 2011 for the first time and it brought the Russian electric -L weather satellite into orbit.

Data of the zenith

Start list

State of the list: February 1, 2013

The launches were either from the Baikonur Cosmodrome in Kazakhstan or from the platform Odyssey in the Pacific Ocean instead of.

¹ NOT necessarily the target orbit of the payload - but the path on which the payload from the upper stage to be exposed.

Planned start

State of the list: February 20, 2014

¹ NOT necessarily the target orbit of the payload - but the path on which the payload from the upper stage to be exposed.