Russia launches a missile-detection satellite
Military personnel at Plesetsk Cosmodrome in Northern Russia launched a Soyuz-2-1b rocket in early hours of Nov. 25, 2021, carrying a classified payload which is believed to be the fifth Kupol satellite for the constellation designed to provide the Kremlin and the Russian military leadership with early warning about missile launches around the world. In 2020, the full deployment of the network was promised by 2024.
Fifth Kupol/EKS launch at a glance:
Fifth EKS/Tundra satellite lifts off
According to the official Russian media quoting the Ministry of Defense, the Soyuz-2-1b rocket with a Fregat upper stage lifted off from Pad 4 at Site 43 in Plesetsk on Nov. 25, 2021, at 04:09 Moscow Time (8:09 p.m. EST on November 24) .
No official information on the nature of the payload has been released but in mid-November 2021, the Russian government warned local population in the Uvat District, west of the Gerasimovka village, in the Tyumen Region about impact of a rocket stage in the area during a military launch scheduled for Nov. 25, 2021, with a backup launch possibility on November 26. The air- and sea-traffic warnings were also issued for a remote area in the Pacific Ocean.
The ground track of the upcoming launch matched previous missions delivering satellites known as Tundra or Kupol for the nation's early warning constellation. The overall network is officially known as EKS OiBU for Edinaya Kosmicheskaya Sistema Obnaruzheniya i Boevogo Upravleniya, which can be translated as "Integrated Space System for Detection and Battle Command" or EKS for short.
During 2020, Russian military officials promised to complete the deployment of the EKS constellation by 2024.
The fifth launch appeared to be following the usual scenario for the deployment of satellites in the EKS constellation. The four-stage Soyuz/Fregat booster lifted off under the simultaneous thrust of the first and second stages, heading southeast along the southernmost corridor available for orbital launches from Plesetsk. The four boosters of the first stage were jettisoned around two minutes into the flight and probably fell around 350 kilometers downrange, most likely at the S28 impact site located in the marshy area where the Vychegda River flows into the Severnaya Dvina River. The second (core) stage continued the powered ascent.
The payload fairing then split into two halves around a minute after the separation of the first stage. Its fragments probably fell in the Western-Siberian Plain, along the Om river.
Less than five minutes into the flight and moments before the second stage completed its burn, the third stage ignited its four-chamber RD-0124 engine, initially firing through the lattice structure connecting the two stages. The second stage then separated and crashed around 1,500 kilometers downrange from the launch site, most likely at the S21 impact site, northeast of the city of Tobolsk in the Tyumen Region.
Around nine minutes into the flight, the third stage released the payload section, including the Fregat upper stage and the Kupol satellite, into a suborbital trajectory before reentering the Earth's atmosphere. Any surviving debris from the third stage should have fallen into the Pacific Ocean just South East of Tasmania.
Shortly after the launch, the Russian Ministry of Defense confirmed that the assets of the Titov Chief Test Space Center within the Russian Air and Space Forces, VKS, had begun tracking the vehicle at 04:11 Moscow Time and that at 04:18 Moscow Time, the Fregat upper stage and its payload had successfully separated from the third stage of the Soyuz launch vehicle.
Approximate ground track during the launch of the EKS (Tundra) satellite.
Fregat space tug maneuvers
During the orbital part of the launch, the Fregat was expected to conduct multiple maneuvers to insert the EKS satellite into its orbit. Most likely, three main engine firings had to be made. The first maneuver initiated within a minute after the separation from the third stage likely placed the stack into an initial parking orbit. The Fregat then probably fired its engine again with the goal of stretching the orbit so that the apogee (the highest point) of this intermediate orbit reached the perigee (lowest point) of the final orbit. Finally, the third Fregat burn could increase the apogee to the required altitude by firing near the peak of the target orbit.
Following the separation of the EKS spacecraft, the Fregat upper stage typically conducts collision avoidance and deorbiting maneuvers. In turn, the satellite has its own propulsion system to make necessary orbit adjustments.
A Soyuz-2-1b rocket is being prepared for launch on Nov. 25, 2021. Click to enlarge. Credit: Russian Ministry of Defense
A Soyuz-2-1b rocket lifts off from Plesetsk on Nov. 25, 2021. Credit: Russian Ministry of Defense