Tsyklon-B (Parus) satellites

Soviet Parus (Sail) satellites comprised the top-secret Tsyklon-B network, which provided communications and navigation signals for the Soviet Navy. The constellation remained in service long after its declassifcation in Russia at the beginning of the 1990s and worked in parallel with the deployment of a new-generation GLONASS navigation network. The Tsyklon-B network was retired after the GLONASS constellation had become fully operational. A total of 96 Parus satellites were launched until 2010.

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A declassified copy of the Tsyklon (Parus) satellite was displayed at the Economic Achievements Exhibit, VDNKhA, in Moscow during the 1970s and 1980s.

Origin of the Parus network

According to the official Russian sources, the development of the modified Parus navigation and communications satellite started in 1971. The first satellite in a series was launched on Dec. 26, 1974, under the official name Kosmos-700. (389) The system was declared operational in 1976 and, as its name implied, it was intended for the use by the Russian navy, particularly by nuclear submarines on the "doomsday watch." The use of satellite navigation would reportedly increase the accuracy of ballistic missiles launched from the sea. (147, 390) The Parus network was apparently based on the previous-generation Tsyklon system first introduced in 1967 and upgraded several times since then. According to ISS Reshetnev, original Tsyklon satellites provided accuracy of one kilometer.

A standard drum-shape satellite bus, known as KAUR-1, developed by NPO PM in Zheleznogorsk served as a platform for both Tsyklon and Parus vehicles. The navigation and command payload for Parus was provided by NII Radiopribor. It became clear from official Russian sources that Parus satellites comprise a system known as Tsyklon-B (76) or Tsyklon-M. (70)

The Parus constellation was a "parallel response" to the first-generation American navigation satellites, known as Transit. The entire constellation consisted of six spacecraft, inserted into a 1,000-kilometer circular orbit with an inclination 82.6 degrees toward the Equator. The plane of orbit of each Parus satellite was separated by 30 degrees. (147) The network reportedly provided a navigational accuracy from 100 to 300 meters, following a 5-15-minute period of satellite tracking. Unlike the second-generation global-positioning system, the access to the signal is only available with intervals lasting from 30 minutes to 1.5 hours.

In addition to their navigation payloads, Parus satellite were believed to be capable of receiving, storing and re-transmitting communication messages by the Soviet military, first of all by the Navy.

The Parus system was also complemented by a four-bird constellation of Tsykada satellites, also designed for the naval use, including civilian vessels. Two networks were used in parallel, where Tsykada satellites' ascending orbital nodes were placed on the opposite side of the globe, relative to ascending nodes of Parus satellites. At least one source, identified Tsykada as a replacement for the (first-generation) Tsyklon satellites. (389) In turn, the Tsykada network was complemented by Nadezhda (Hope) satellites, equipped with KOSPAS-SARSAT rescue navigation hardware. (383)

According to ISS Reshetnev (formerly NPO PM), Tsylkon-B satellites were replaced by the Meridian constellation (apparently, in their communications function).

Recent Parus missions

2001 June 8: A Kosmos-3M launcher returned to flight on Friday, June 8, with the successful launch of a military satellite. The two-stage rocket blasted off from Russia's Northern Cosmodrome in Plesetsk at 19:12 Moscow Time (11:12 p.m. EDT) on June 8. According to the Russian Space Forces, the spacecraft, announced as Kosmos-2378, successfully reached the orbit. The parameters of its orbit (1,023 by 981 kilometers, inclination 82.9 degrees toward the Equator) suggest that the satellite belongs to the Tsyklon-B navigation and communications network, comprised of the Parus ("Sail") spacecraft. The Kosmos-3M was grounded since November 2000, when the rocket failed to deliver a US QuickBird imaging satellite, due to the second stage failure. The latest launch was 402nd for the Kosmos-3M, since the rocket entered service in 1967. The June 8 launch has been delayed since April 27 by the problems with the control systems of the steering engines on the second stage of the launcher. ITAR-TASS news agency quoted Anatoly Perminov, the commander of the Space Forces, saying that of the seven upcoming launches, three will carry military payloads.

2003 June 4: The Russian military launched a classified payload from country's northern cosmodrome in Plesetsk on June 4, 2003. A Kosmos-3 booster blasted off at 23:23 Moscow Time and the spacecraft was expected to reach its final orbit at 00:27 Moscow Time on June 5, 2003. The payload was officially identified as Kosmos-2398. Although no information on the purpose of the spacecraft had been released, it is known that the Kosmos-3 booster is routinely used to deliver low-orbital navigation and communication satellites for the Russian military.

2004 July 22: Russian military orbited a classified payload from the nation's northern launch facility. A Kosmos-3M rocket blasted off from Site 132 in Plesetsk on July 22, 2004 at 21:46:28 Moscow Time, press service of the Russian Space Troops, VKS, said. A classified military payload was successfully inserted into its orbit at 22:49:30 Moscow Time. Kosmos-3M rockets are routinely used to deliver navigation and low-orbit communications satellites for the Russian military.

2005 Jan. 20: For the second time in a month, a Russian rocket apparently delivered its payload into a lower-than-planned orbit. A Kosmos-3M launcher blasted off from Russia's northern cosmodrome in Plesetsk at 06:00 Moscow Time on Jan. 20, 2005, carrying the Parus navigation satellite for the Russian military along with a "piggyback" Universitetskiy-Tatyana spacecraft for the Moscow State University, MGU.

The Kosmos-3M launcher used in the mission also carried an enlarged payload fairing designed to accomodate the three-meter wide parabolic antenna of the SAR-Lupe reconnaissance satellites, developed for the German military and slated for launch on a future mission of the Kosmos-3M rocket in 2005. At the time of the launch, OHB-System AG in Bremen was integrating the SAR-Lupe satellites. The first of five flight satellites has already been fitted with the synthetic aperture radar supplied by Alcatel Space, Toulouse, and Tesat Spacecom, Backnang, for capturing image data.

The SAR-Lupe radar-image-based reconnaissance system being built for the German Federal Armed Forces comprises five satellites and a ground station for controlling the satellites and evaluating the downloaded data. Located in Gelsdorf, the ground station has now very largely been completed.

According to official Russian sources, both satellites successfully reached orbit and separated from the upper stage of the launch vehicle at 07:02 Moscow Time on Jan. 20, 2005. However, ground observations found the Parus spacecraft, officially identified as Kosmos-2414, in a 909.5 by 966.7-kilometer orbit with the inclination of 82.9 degrees toward the Equator. In the past, satellites of this type would be inserted into orbits with an apogee of around 1,000 kilometers above the Earth surface. Lower altitude could be caused by a premature shutdown or the lack of thrust in the propulsion system of the launch vehicle.

However, official Russian sources later claimed that both satellites were successfully delivered. The Tatyana satellite failed unexpectedly in March 2007, possibly as a result of a collision with a piece of space junk.

2007 Sept. 11: Russian military launched a classified payload, believed to be a navigation satellite. A Kosmos-3M rocket lifted off from Russia's northern cosmodrome in Plesetsk on Sept. 11, 2007, at 17:05 Moscow Time. According to the representative of the Russian space forces, KVR, quoted by the Interfax AVN agency, the launch vehicle carried a military payload for the Ministry of Defense.

The payload reached its operational orbit at 18:08 Moscow Time, as expected, and some one hour later, as the satellite entered within range of ground control stations, it established normal contact with the ground, officials said. The Kosmos-3M rocket routinely launches military satellites from the Parus (Sail) series.

2009 July 21: Russia launched a pair of satellites from its northern cosmodrome. A Kosmos-3M rocket lifted off on July 21, 2009, from Plesetsk, carrying two payloads, believed to be a Parus military navigation satellite (later named Kosmos-2454) and the Sterkh emergency rescue signal spacecraft. The mission was previously expected to take place in 2008.

2010 April 27: A Russian rocket launched a classified payload from Russia's northern cosmodrome. A Kosmos-3M rocket lifted off from Pad 1 at Site 132 in Plesetsk on April 27, 2010, at 05:05 Moscow Summer Time. The spacecraft was expected to separate from the upper stage of the launch vehicle at 06:08 Moscow Time, while out of range of the Russian ground control stations. According to the Russian space forces, Titov test and control center successfully established contact with the satellite at 06:41 Moscow Time on April 27. The payload was officially identified only as Kosmos-2463, but it is believed to be a Parus spacecraft for military navigation and communications. According to this month's statement by the commander of the Russian space forces Oleg Ostapenko, the current mission would one of three last launches of the veteran Kosmos-3M launch vehicle. The Russian military planned to use all remaining rockets in its storage, with no additional production scheduled.

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Next chapter: GLONASS navigation network

Written by Anatoly Zak; last update: December 9, 2017

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Tsyklon was the first Soviet navigation satellite and it also carried communications functions. Credit: ISS Reshetnev


A Parus navigation satellite during assembly at ISS Reshetnev. Click to enlarge.


A Kosmos-3M rocket launches the final Parus navigation satellite on April 27, 2010.


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