|Manufacturer||Yuzhmash, JSC "Khartron" (control system)|
|Country of origin||Ukraine|
Baikonur Site 90
Plesetsk Site 32
|First Stage - 11K69|
|Engines||1 RD-261 + RD-855 Vernier engine|
|Thrust||3,032 kilonewtons (682,000 lbf)|
|Specific impulse||301 sec|
|Burn time||120 seconds|
|Second Stage - 11S692|
|Engines||1 RD-262 + RD-856 Vernier engine|
|Thrust||941 kilonewtons (212,000 lbf)|
|Specific impulse||318 sec|
|Burn time||160 seconds|
|Specific impulse||330 sec|
|Burn time||370 sec|
The Tsyklon-4 or Cyclone-4, also known as Tsiklon-4, is a Ukrainian carrier rocket which is being developed for commercial satellite launches. Derived from the Tsyklon-3, it has a new third stage, a larger payload fairing, and a modernised flight control system compared to its predecessor. Control system has been developed by JSC Khartron.
Tsyklon-4 is a three-stage-to-orbit expendable launch system built on the successful Tsyklon-3 rocket and it uses its first two stages. The new features are mostly concentrated in the newly developed third stage:
- The third stage has a three times larger propellant capacity;
- The new rocket engine RD-861K with multiple ignition capability (3 to 5 times);
- A modern western-like control system capable of precise orbit injections;
- A new fairing derived from Ariane 4 is under development. It has a diameter of 4 meters, controlled temperature and cleanness conditions inside.
Tsyklon-4 will also improve the fueling system, allowing safe capture of toxic vapors from the Tsyklon's hypergolic propellant.
Launch facilities 
Development history 
Development began in 2002, with the maiden flight aimed for 2006. Following a series of production delays, this has slipped, and is now scheduled for 2014. Alcântara Cyclone Space has been established as a launch service provider for the Tsyklon-4.
In 2008, it was reported that Brazil may pull out of the programme in favour of an alternative partnership between it and Russia to develop an Angara-derived rocket. However late 2009 Ukrainian President Viktor Yushchenko and Brazilian President Luiz Inácio Lula da Silva signed a joint declaration which included a commitment to launch the first Tsyklon-4 by the end of 2010 from Alcântara. This did not occur, and it is now to launch no earlier than 2014. 
See also 
- Wade, Mark. "Tsyklon 4". Encyclopedia Astronautica.
- "Cyclone-4 Launch Vehicle". NPO InterCoS.
- Control systems for intercontinental ballistic missiles and launch vehicles
- Krivonosov, Khartron: Computers for rocket guidance systems
- Stathopoulos, Vic. "Tsyklon". Aerospaceguide.net.
- "Brazil - Launch Vehicles". GlobalSecurity.org.
- "Tsyklon (Cyclone)". Space Launch Report.
- "Cyclone 4". National Space Agency of Ukraine.
- Zaitsev, Yury (September 17, 2008). "Russia Begins Elbowing Ukraine Out From Brazil's Space Program". RIA Novosti.
- "Brazil, Ukraine to launch rocket together in 2010". UNIAN. December 3, 2009.