'Cyclone-2'), also known as Tsiklon-2 and Tsyklon-M (known as SL-11 by the United States DoD), GRAU index 11K69, was a Soviet, later Ukrainian, orbital carrier rocket used from the 1960s to the late 2000s.

A derivative of the R-36 ICBM, and a member of the Tsyklon family, the Tsyklon-2 made its maiden flight on 6 August 1969, and conducted 106 flights, the last one occurring on 24 June 2006.

It was the most reliable Soviet/Russian carrier rocket ever used, and launched more than 100 times having failed only once, and the second most reliable carrier rocket overall, behind the Atlas II that was launched only 63 times.

[2] Along with other R-36 family member Tsyklon-3, the Tsyklon-2 was retired in favor of new-generation and all-Russian carrier rockets, such as the Angara and Soyuz-2.

However, it did not have a third stage, like the Tsyklon-3 did, also it was slightly shorter and had a lower weight mass when fueled.