Rokot

Rockot (Rokot)

Function	Orbital carrier rocket
Manufacturer	Khrunichev State Research and Production Space Center
Country of origin	Russia
Cost per launch	US$41.8 million [1]
Size
Height	29 metres (95 ft)
Diameter	2.5 metres (8 ft 2 in)
Mass	107,000 kilograms (236,000 lb)
Stages	3
Capacity
Payload to LEO
Mass	1,950 kilograms (4,300 lb)
Payload to SSO
Mass	1,200 kilograms (2,600 lb)
Launch history
Status	Retired
Launch sites	Baikonur Plesetsk 133/3
Total launches	34
Success(es)	31
Failure(s)	2
Partial failure(s)	1
First flight	20 November 1990 26 December 1994 (orbital)
Last flight	26 December 2019
First stage
Diameter	2.5 m (8.2 ft)[1]
Engines	3 RD-0233 (15D95) 1 RD-0234(15D96)[2][3]
Thrust	2,080 kN (470,000 lbf)[4][5]
Specific impulse	310 s[4]
Burn time	120 s
Propellant	N 2O 4 / UDMH
Second stage
Diameter	2.5 m (8.2 ft)[1]
Engines	1 RD-0235 (15D113) 1 RD-0236 (15D114)[2][3]
Thrust	255.76 kN (57,500 lbf)[6][7]
Specific impulse	310 s[6]
Burn time	180 s
Propellant	N 2O 4 / UDMH
Third stage – Briz-KM
Engines	1 S5.98M
Thrust	19.6 kilonewtons (4,400 lbf)
Specific impulse	325 s
Burn time	3 ks
Propellant	N 2O 4 / UDMH

Rokot (Russian: Рокот meaning Rumble or Boom), also transliterated Rockot, was a Russian space launch vehicle that was capable of launching a payload of 1,950 kilograms into a 200 kilometre Earth orbit with 63° inclination. It was based on the UR-100N (SS-19 Stiletto) intercontinental ballistic missile (ICBM), supplied and operated by Khrunichev State Research and Production Space Center. The first launches started in the 1990s from Baikonur Cosmodrome out of a silo. Later commercial launches commenced from Plesetsk Cosmodrome using a launch ramp specially rebuilt from one for the Kosmos-3M rocket. The cost of the launcher itself was about $15 million in 1999;^[8][9] The contract with ESA for launching Swarm in September 2013 was worth €27.1 million ($36 million).^[10]

Specifications[]

Rokot's total mass was 107 tonnes, its length 29 metres and its maximum diameter 2.5 metres. The liquid-fueled rocket comprised three stages. The lower two were based on the Soviet UR-100N ICBM; the first stage used an RD-0244 engine, while the second stage used an RD-0235. The third stage was a Briz-KM (Russian: Бриз-КМ meaning Breeze-KM), which has a mass of about 6 tonnes when fuelled, and is capable of flying for 7 hours and reigniting its engine six times during flight, allowing different satellites to be placed into different orbits. All stages used UDMH (unsymmetrical Dimethylhydrazine) as fuel and dinitrogen tetroxide as oxidiser. The Strela is a similar rocket, also based on the SS-19.^[8]

History[]

Preparing the Rokot rocket for launch. Plesetsk cosmodrome

The first suborbital test launch succeeded on 20 November 1990 from Baikonur Cosmodrome. On 26 December 1994 Rokot brought its first satellite into Earth orbit. In 1995, Khrunichev State Research and Production Space Center formed a company with German DaimlerBenz Aerospace to market Rokot launches for commercial use. Later, the company was renamed to Eurockot Launch Services. Eurockot bought 45 Rokots from the Russian strategic missile forces to build its inventory. In 2000, Eurokot was partly bought by the German company Astrium GmbH, a shareholder of Arianespace. Astrium then held 51% of Eurockot's shares, while Khrunichev held 49%.^[8]

Although there are several silos in Baikonur capable of launching Rokots, it was decided to build an open, non-siloed launch pad at Plesetsk Cosmodrome instead. This is because of concerns that the amount of noise generated during a silo-based launch would damage satellites. In the new pad, Rokot was wheeled up to the structure in a vertical position, and then embraced by its launch tower. The payload was lifted by a crane and placed on top of the bottom two stages. The procedure was in contrast to other Russian launchers, which had traditionally been assembled horizontally and then transferred to the launch site via railways. The first launch from Plesetsk took place on 16 May 2000.^[8]

After six entirely successful launches, a launch failure occurred on 8 October 2005, leading to the loss of the European Space Agency's CryoSat spacecraft. The launch vehicle 2nd stage main engine was not shut down properly, resulting in a catastrophic failure and automatic termination of the launch mission by the on-board computer. The payload was lost. After the failed CryoSat launch, all Rokot launches were suspended until the failure was identified. The root cause was unambiguously identified; it was a failure in programming of the Briz-KM (which was contracted to the company JSC "Khartron"). The failure of this high-profile mission led to major reforms in Khrunichev: the director of the company Alexander Medvedev was dismissed, new launch procedures were introduced, the lines of management were straightened out to catch errors and the new Khrunichev chief, , was required to report directly to the head of the Russian Space Agency, Anatoli Perminov.^[8] Corrective measures for Rokot's return-to-flight were implemented for the South Korean Kompsat-2 earth observation satellite launch which took place successfully on 28 July 2006. The Korean side reportedly praised the level of service they received, encouraging the Rokot team to rebuild its order book.^[8]

Another launch failure occurred in February 2011, when a Briz-KM malfunction^[11] resulted in the Geo-IK-2 No.11 satellite being placed into a lower orbit than planned.

The Rokot version with a Ukrainian control system stopped flying after 2019, due to Ukraine's ban on technology exports to Russia.^[12] Rokot had its final flight on December 26, 2019.^[13] A fully Russian-made Rokot light carrier rocket, named Rokot-M, may begin operations as soon as 2022. The Rokot-M launch vehicle is intended for the Russian defense department.^[14]

Launch history[]

See also[]

• Comparison of orbital launchers families

References[]

External links[]

Wikimedia Commons has media related to Rockot.

• Website of Khrunichev State Research and Production Space Center, Launch Service Provider
• Rockot history on RussianSpaceWeb.com