soyuz 2.1b, eks 5

EKS 6 (Tundra 6) | Soyuz 2.1b/Fregat

Lift Off Time
(Subject to change)
November 02, 2022 – 07:30 UTC | 10:30 MSK
Mission Name
EKS 6 (Tundra 6)
Launch Provider
(What rocket company is launching it?)
(Who’s paying for this?)
Russian Ministry of Defense
Soyuz 2.1b
Launch Location
Unknown Pad, Plesetsk Cosmodrome, Russian Federation
Payload mass
~ 1200-1500 kg
Where are the satellites going?
Will they be attempting to recover the first stage?
No, this is not a capability of Soyuz
Where will the first stage land?
It will crash in remote regions of northern Russia
Will they be attempting to recover the fairings?
No, this is not a capability of Soyuz
Are these fairings new?
How’s the weather looking?
This will be the:
6th launch of an EKS (Tundra) satellite
– 6th launch of a Soyuz 2.1b in 2022
– 78th launch of a Soyuz 2.1b variant
– 8th launch from the Plesetsk cosmodrome in 2022
150th orbital launch attempt of 2022
Where to watch
If an official livestream becomes available, you can find it here

What Does All This Mean?

ROSCOSMOS will launch their next Edinaya Kosmicheskaya Sistema (EKS) or Integrated Cosmos System satellite on a Soyuz 2.1b rocket for the Russian Ministry of Defense. EKS 6 (Tundra 6) is the sixth satellite of the series. The rocket will lift off on November 2, 2022, from the Plesetsk Cosmodrome, in Russia. This mission will mark the eighth launch from this launch site.

EKS 6 (Tundra 6) Mission

As is typical with military satellites, their naming conventions can be quite confusing. The official name of the satellite, as mentioned above, is Edinaya Kosmicheskaya Sistema (EKS) or, in English: Integrated Cosmos System. Another common name is Tundra, which seems to have no specific meaning.

The EKS is a new-generation early-warning satellite system. The Tundra satellites operate in highly elliptical orbits and are designed to monitor regions from which ballistic missiles could potentially be launched against Russia.

eks 5, tundra 5, soyuz 2.1b
Render of the EKS satellite with solar panels deployed. (Credit: 3d_molier)

There were two generations of predecessors of the EKS system: the US-K and US-KMO satellites. The latter worked in highly elliptical orbits and had a significant disadvantage in its viewing geometry: the satellites could easily be blinded by the light of the setting Sun. The latter ancestor was introduced in 1991, was equipped with upgraded infrared sensors, and operated in geosynchronous orbits.

The plans for a new EKS constellation (military index 14K032, sometimes referred as “Kupol”, meaning “dome”) were announced in 1999. This constellation comprises of satellites manufactured by RKK Energiya and operating in both highly elliptical orbits (Tundra satellites, military index 14F142) and geostationary orbits.

Satellite Specifics

Each EKS satellite serves the purpose of providing early-warning of global missile launches and baseline communications for the military. It can detect ballistic missile launches from land and sea and predict their trajectory. These types of satellites are widespread in the militaries of nations that have access to orbit. The design lifetime is at least 7.5 years.

The satellite bus, or the power center and foundation of the satellite, is built by RKK Energia and is known by the acronym “USP”. The acronym stands for the Universal Space Platform, also known as Victoria. As the name suggests, this bus is flexible and can accommodate many satellite designs and needs. It also can operate anywhere from a low Earth orbit to a geostationary orbit. The USP bus cannot raise or lower its orbit and therefore depends on direct orbit injection. It does not use a pressurized compartment for the onboard electronics.

Power Capabilities3000 W
Payload Weight Capabilities (LEO)1,000 kg (2,200 lb)
Stabilization Electric or chemical propulsion on three axis
USP Dry Mass950-1,200 kg
Payload Mass250-300 kg

More information on the EKS constellation can be found here.

EKS Orbits

Five EKS satellites are currently in orbit, with all active and operational as of publication. Each has been placed in a Molniya orbit of about 38500 x 1600km, 63.5°. It is reasonable to conclude that the EKS 6 satellite will join the others in a similar orbit.

eks 5, tundra 5, orbit
EKS orbit and Earth’s surface visibility. (Credit: Spaceflight101/JSatTrak)

History And Future

EKS 1November 17, 201538552 x 1626 km, 63.37°Active
EKS 2May 25, 201738552 x 1626 km, 63.37Active
EKS 3September 26, 201938537 x 1646 km, 63.83°Active
EKS 4May 22, 202035807 x 1654 km, 63.83°Active
EKS 5November 25, 2021Molniya, 38761 x 1609 km, 63.83°Active

A total of ten satellites has been the stated goal for the group, with all to be deployed by 2022. However, that no longer seems possible due to the limited amount of time remaining.

What Is Soyuz 2.1b?

ROSCOSMOS’s Soyuz is a multi-use medium-lift launch vehicle that was introduced in far 1966 and since then has been the workhorse of the Soviet/Russian space program. It is capable to launch civilian and military satellites, as well as cargo and crewed missions to the ISS. Over the decades, several variants of the Soyuz rocket have been developed. Soyuz 2.1b is one of its latest iterations that belongs to the Soyuz 2 rocket family.

A Soyuz 2.1b rocket, launch pad, Arktika-M mission
A Soyuz 2.1b rocket on the launch pad. (Credit: ROSCOSMOS)

The rocket consists of three stages, all of them are expendable. When launching to the ISS, Soyuz 2 can be flown with either a Progress capsule or a Soyuz spacecraft.

Soyuz 2.1b is about 46.3 meters (152 ft) in height and 2.95 meters (9 feet) in diameter. The vehicle’s total lift-off mass is approximately 312,000 kg (688,000 lb). The rocket’s payload lift capacity to low-Earth orbit (LEO) is between 6,600 and 7,400 kg depending on the launch site.


First StageSecond StageThird Stage
Engine 4 RD-107ARD-108ARD-0124
Total Thrust 840 kN (188,720 lbf),
sea level
1,020 kN (229,290 lbf),
792 kN (178,140 lbf),
sea level
922 kN (207,240 lbf),
294 kN (66,094 lbf),
Specific Impulse (ISP)263 s, sea level
320 s, vacuum
258 s, sea level
321 s, vacuum
359 s, vacuum

Side Boosters

The first stage of the Soyuz 2.1b rocket is composed of 4 side boosters that are powered by RD-107A engines. Each one of the boosters has a conical shape and a dry weight of 3,784 kg. It is approximately 19.6 meters in length, with a diameter of 2.7 meters. Each side booster has two vernier thrusters that are used for flight control.

The RD-107A engine runs on rocket-grade kerosene (RP-1) and liquid oxygen (LOx). The propellants are stored in the pressurized aluminum alloy tanks, the kerosene tank is located in the cylindrical part of the booster, and the LOx one is in the conical section. Each one of those engines have 4 combustion chambers and together they are capable of producing a thrust of 840 kN at sea level and 1,020 kN in a vacuum.

"Korolev cross", Progress MS-16 mission
“Korolev cross” seen during Stage I separation on the Progress MS-16 mission. (Credit: ROSCOSMOS’s livestream)

Perhaps, the most spectacular moment of the Soyuz 2 rocket’s launch is the separation of the first stage. It happens approximately 2 minutes after the launch. The boosters perform a pattern, known as the “Korolev cross” (named after Sergei Korolev, a very important figure of the USSR space program and history).

Second And Third Stages

The center core stage is powered by a single RD-108A engine, and the upper stage is fitted with a single RD-0124 engine. Both of these engines run on RP-1 and LOx and have 4 combustion chambers. The second stage is 27.1 meters long, with a diameter of 2.95 meters, and a dry mass of 6,545 kg. It has 4 vernier thrusters for three-axis flight control.

The third stage of a Soyuz 2 rocket has a height of 6.7 meters, a diameter of 2.7 meters, and a dry mass of 2,355 kg. One interesting thing about the RD-0124 engine on this stage is that it starts its ignition sequence prior to stage separation. This process is called “hot fire staging”.

Rocket-motor-RD-0124б, Soyuz 2.1b
RD-0124 motor at Salon-du-Bourget 2013. (Credit: Pline)

Fregat Upper Stage

Flight qualified in 2000, the Fregat upper stage is an autonomous and flexible stage that is designed to operate as an orbital vehicle. It extends the Soyuz launcher’s capability, covering a full range of orbits (LEO, SSO, MEO, GTO, GEO and Earth escape). Fregat is independent of all the other stages, as it has its own guidance, navigation, attitude control, tracking, and telemetry systems. The S5.92 engine burns storable propellants – UDMH (unsymmetrical dimethylhydrazine) and NTO (nitrogen tetroxide). The Fregat upper stage is encapsulated in a fairing with the payload and a payload adaptor/dispenser. Upgraded Fregat-M has additional ball-shaped compartments on top of its propellant tanks, which allows to increase the load capability of the propellant.

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