Probably we will not see any more launches of Dnepr rocket in future, due the decision of Russian authorities.
According to TASS agency, Colonel-General Sergey Karakayev commander of Russian Strategic Missile Troops informed TASS journalist on Wednesday, that further development and launches of Dnepr rocket are suspended:
“The Russian president decided to suspend the Dnepr conversion program in April 2015,”
Decision was taken after last launch of Dnepr on 26 March 2015. It seems that again politics decided about future of cooperation between Russian and Ukrainian space industries. Dnepr rocket was utilized by joint venture Company ISC Kosmotras established in 1997 by Russia, Ukraine and Kazakhstan. Russia held 50% shares and provided rockets decommissioned under START treaty (Ministry of Defense was one of the shareholders from Russian side and was able to offer 150 decommissioned rockets with possibility of launch to 2020) for further modernization on Ukraine by State Design Bureau Yuzhnoye (rebuilt was performed in State Enterprise “Production Association Yuzniy Machine Building Plant” and Scientific and Production Enterprise Khartron-ARKOS). Participation of Kazakhstan was limited to providing launch site in Baikonur by State Enterprise “Infrakos” and general ecological support performed by “Infrakos-Ekos”. Space agencies from all three countries were responsible for general support of the program. Since 1999, Dnepr was utilized in 22 missions with only one failure on July 26, 2006 caused by broken pumping hydraulic drive of fourth combustion chamber. Rocket crashed in place distant about 150 km from Baikonur with no any casualties. Due the pollution of crash site by fuel, Russia was forced to pay $1.1 million to Kazakhstan for compensation. During its operating history Dnepr hold record of number of spacecrafts lifted to the orbit during one mission two times. In 2007 Dnepr put into orbit 14 satellites – record was beaten by Minotaur I rocket on 2013 (29 satellites during one mission). One day after Minotaur I, on 21 November 2013 Dnepr lifted 32 satellites in one mission – this time record belonged to Dnepr for one year and was taken by Antares rocket in 2014 which successfully put into orbit 34 satellites. ISC Kosmotras was using Dnepr for commercial purposes; satellites lunched on atop of Dnepr were mostly research or communication spacecrafts.
Dnepr was converted ICBM missile known as SS-18 Satan or R36. It was designed back in the seventies by Ukrainian Yuzhnoe Design Bureau and modified by Yuzhnoe and Scientific and JSC “Khartron” (Khartron-ARKOS is part of JSC “Khartron”). Main modification was adopting appropriate payload fairing instead warhead and changing control system for modern one manufactured by JSC “Khartron”. It was designed as three stage rocket with liquid fueling system propelled with toxic N2O4/UDMH. First stage is powered by one RD-264 module consisting four RD-263 engines. It provides 4520 kN of thrust with burn time of 130 s. Second stage is powered by one RD-0255 module which consist one central RD-0256 engine combined with four Vernier RD-0257. They were providing 755 kN of thrust total for 190 seconds of burn time. Third stage was powered by one operating for 1000 seconds RD-869 engine with thrust at 18.6 kN. Third stage is combined with payload fairing resistant for hot gases emitted by propulsion. After separation from second stage, third stage is turning upside-down and lifting cargo into desired altitude. Due the fact, that RD-869 is not restartable unit, cargo separation is performed during engine of third stage is operating. Such procedure is necessary to prevent extending number of space debris. There was possibility of designing upper module (called Space Tug) for more precise injecting satellites into orbit, but it would be necessary to reduce payload capacity. Dnepr was usually lifting one main payload and additional smaller objects like Cubesat satellites. Rocket was able to lift 3600 kg in LEO missions for altitude of 300 km and inclination of 50.6° or 2300 kg to altitude of 300 km during SSO missions (altitude of 300 km and inclination of 98.0°). Rocket dimensions are: height – 34.3 m, diameter – 3 m, weight – 211000 kg. One of interesting features of Dnepr was launch method. In both launch sites – Baikonur and Dombarovsky Air Base – Dnepr was launched from special silo. To support rocket in start, special hot gas generator was adopted under the rocket. While it was turned on, rocket utilizing its thrust was leaving silo and separate from generator which using own small engine was reaching safe distance from silo and Dnepr. Engines of Dnepr were igniting 20 m above the silo. So in fact real first stage of rocket is hot gas generator. Dnepr was never adopted for launching from conventional launch tower like Zenit rocket, but still it was never an issue.