This partnership held up together after the breakup of the Soviet Union, but all cooperation ended after Russia’s invasion of Ukraine in February 2022. (Russia even went so far as to strike the factory where Zenit rockets were once made with an intermediate-range ballistic missile last November).
With the Soyuz-5 booster, Russia seeks to replace both the Zenit family of rockets and the aging Proton-M launch vehicle. The new Irtysh rocket will have slightly larger main propellant tanks than the Zenit-2 vehicle, giving it a lift capacity of about 17 metric tons to low-Earth orbit.
Not much new here
Probably the most interesting element of this rocket is its engine, the RD-171MV. This is based on technology that goes back decades to the Energia launch vehicle, which the Soviet Union used to launch the Buran space shuttle. A modified version, the RD-171, was used for Zenit rockets. Unlike the previous engines, this newest version does not use any Ukrainian components.
This line of rocket engines, powered by kerosene and liquid oxygen, produces more than three times the thrust of a NASA Space Shuttle main engine. They are the most powerful liquid-fueled rocket engines in the world.
One key question for the Russian space program is whether the Soyuz-5 rocket can become commercially successful and attract non-Russian launch business. The country will also continue to fly the Soyuz-2 launch vehicle, which is presently used for crewed missions and the newer line of Angara rockets.
It’s notable that the Russian space program—which has had its funding curtailed to help pay for the war against Ukraine—has managed to bring the Soyuz-5 to the launch pad. However, a far more significant achievement would be delivering another Soyuz rocket in development, the Soyuz-7, also known as Amur. This is because the Amur rocket marks a significant break from traditional Russian designs.
This rocket, with new liquid oxygen-methane engines, is intended to replace the Soyuz-2 vehicle. The rocket could also be more price competitive, as it is intended to have a reusable first stage. The vehicle’s debut has been repeatedly pushed back, however, with Russia now expected to debut the vehicle no earlier than 2030.
