ACTS interior

2005: Roots of the Russian-European cooperation in manned space flight

At the beginning of 2004, the US government announced its intention to withdraw from the International Space Station program and, instead to return American astronauts to the Moon. NASA's space station partners were left to decide for themselves where to go in space. Initially, Russians tried to convince Europeans to pull resources to develop a new generation reusable space plane, however in December, European ministers rejected the idea.

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Soyuz lunar 2006: The ACTS concept

A new plan for the Russian-European cooperation in the piloted space program was conceived around Spring 2006. This time, the two sides considered combining funds, hardware and expertise to parallel the US effort to return astronauts to the Moon. The idea was based on previous studies, which looked at upgrading the European ATV cargo ship with a Russian-built reentry vehicle, which would enable it to return cargo or even people to Earth.

Soyuz ACTS 2007: Initial ACTS studies

Russian and European space officials were expected to choose what they identified as an "initial preferred concept" for a future crew vehicle, as early as May or June 2007. However, political problems inside Russia and between the two partners delayed the project. Disagreements over the direction of the Russian space program resulted in the ouster of Nikolai Sevastyanov, the head of the nation's prime contractor in the human space flight -- RKK Energia.


2008: Deciding spacecraft architecture

The Russian-European talks resumed in September 2007. Initially, Russian and European space officials chose a bell-shaped crew module as a preferred configuration for the next-generation manned spacecraft. The new vehicle could accommodate from four to six people on a journey to the lunar orbit. However by the beginning of 2008, a cone-shape capsule, resembling NASA's Apollo spacecraft, had emerged a winner.


2009: Starting preliminary design of PPTS

By the beginning of 2009, the negotiations between Roskosmos and ESA broke down due to numerous technical and political issues. Instead, Roskosmos ordered its industry to come up with the proposals for the new-generation spacecraft. Upon choosing the prime developer in April 2009, the agency expected the industry to complete the preliminary design of the vehicle by June 2010.


2010: Re-examining options

In January, speaking at the 34th Korolev Readings, the head of RKK Energia Vitaly Lopota said that early missions of the PTK NP spacecraft could take place from Baikonur, Kazakhstan. The Ukrainian-built Zenit launcher or a similar Russian-built vehicle would be a likely candidate to carry the spacecraft, since the rocket had the payload capacity of up to 13 tons, needed to lift the future spacecraft and the Zenit had an operational launch pad in Baikonur.


2011: Technical project

Refining design of the spacecraft and its components became the main purpose of this phase of development known as the Technical Project. In addition to the work on blueprints and manufacturing of various elements for experiments, the Technical Project also included the construction of full-scale prototypes of the spacecraft.


2012: Lunar PTK NP

Anticipating the latest direction of the Russian space policy and possible budget restrictions, RKK Energia quietly dropped its plans to develop several variants of PTK NP ships for servicing the space station, autonomous flights in the Earth orbit or reaching into deep-space. Instead, a single spacecraft with the primary goal of carrying crews to lunar orbit has emerged as the focus of the PTK NP project during 2012.


2013: To be or not to be

With the completion of the design, the PTK NP project reached crossroads, as the Russian government had to commit the spacecraft to metal (and real expenses), postpone it or cancel it altogether. Ironically, Russian space agency was facing this critical decision, as NASA's leadership publicly rejected a leading role for the US in any lunar-landing effort.


2014: New delays

During 2014, the development of the next-generation manned spacecraft, PTK NP, was to go from the drawing board to experimental prototypes but a virtual absence of accolades in the official Russian media about development progress could spell trouble for the project. This silence became really deafening as NASA brought a prototype of its Orion spacecraft to the launch pad in December for an unmanned test mission.


2015: Scaling down

During 2015, Russian engineers re-tailored the prospective human space flight program for lighter, cheaper rockets to reflect severe cuts in the nation's space budget in the previous year. According to the latest plans, the next-generation spacecraft could carry its first crew in 2024, followed by a manned mission into lunar orbit in 2025.


2016: Finishing paper phase

In 2016, technical and financial problems forced the developers to abandon a four-launch scenario for the lunar expeditions based on Angara-5V rockets. To reach anywhere beyond the low Earth orbit, the new-generation transport ship had to fall back to a non-existing super-heavy launcher. Still, a lunar expedition remained the official goal of the Russian space program, even though Russian cosmonauts were not expected to walk on the Moon until at least 2030.


2017: PTK approaches experimental phase

In 2017, developers were preparing to build the first major experimental components of the PTK Federatsiya spacecraft for initial full-scale tests. In the meantime, Roskosmos switched PTK's rocket again, this time, from the Angara-5P to the Soyuz-5. It also meant that the flight testing of the Federatsiya would now originate from Baikonur. The first launch had to be postponed to 2022.


2018: Federatsiya to set sail without its key features (INSIDER CONTENT)

The latest financial problems in the Russian space program forced the developers of the PTK Federatsiya spacecraft to drastically simplify its sophisticated rocket-powered landing system and emergency escape rockets conceived for the original version of the next-generation spacecraft.


2019: PTK begins appearing in metal (INSIDER CONTENT)

The long-delayed work on Russia's new-generation transport spacecraft might be postponed again, experts familiar with the matter say. In the meantime, first pieces of the PTK structure were forged.


2020: Orel to get drastic changes in its landing systems (INSIDER CONTENT)

In 2020, engineers at RKK Energia, the prime developer of the PTK Orel new-generation crew vehicle, and their sub-contractors were working on a major re-design of key components of the ship's landing system, while preparing the full-scale assembly of test prototypes and the first flight-worthy vehicle.

2021: The Orel spacecraft faces uncertainty again (INSIDER CONTENT)

In 2021, Russian efforts to build a replacement for the Soyuz crew vehicle continued inching forward, however, the future transport lost its ride to the lunar orbit in the foreseeable future, as limited funds forced Roskosmos to increasingly re-focus on near-Earth space.


2022: Roskosmos struggles to re-purpose PTK for space station (INSIDER CONTENT)

In 2022, Russian engineers began redesigning their unbuilt lunar transport spacecraft for crew-delivery missions to an Earth-orbiting space station. However, the nascent effort faced severe mass restrictions and tight deadlines in an uncertain financial climate.


2023: Stalled crew vehicle threatens future of Russian space flight (INSIDER CONTENT)

By 2023, the PTK project had become a make-or-break effort for the Russian piloted space flight program that risked an irreversible end after the retirement of the International Space Station, ISS.


NEW, Feb. 5: 2024: Roskosmos mulls long-term space station transport development (INSIDER CONTENT)

By 2024, the Russian space industry proposed a four-step plan for the prospective crew and cargo transport system, which would be used to support the national space station project well into the 2030s and beyond.


Overall design as of 2020 (INSIDER CONTENT)

In 2020, Russian engineers were finalizing the overall architecture of the Orel next-generation crew vehicle on the drawing board, as some of its components were appearing in metal.

Emergency Escape System, SAS, for the Federatsiya spacecraft (INSIDER CONTENT)

Like all its predecessors, the PTK Federatsiya spacecraft will be equipped with an emergency escape system, SAS, specifically designed to pull the crew capsule to safety in case of a launch vehicle failure during the ascent to orbit.


BAS escape rocket for the Federatsiya spacecraft (INSIDER CONTENT)

In 2017, the developers of the PTK Federatsiya spacecraft redesigned its Emergency Escape System to save time and money in the early phase of the program.


SAS development in 2020 (INSIDER CONTENT)

In 2017, the developers of the PTK Federatsiya spacecraft redesigned its Emergency Escape System to save time and money in the early phase of the program.


Return Vehicle, VA

After several years of early research, engineers at RKK Energia defined the overall structural design of the crew module during the preliminary development of the PTK NP project in 2010. The conical structure of the module was subdivided into the command compartment, KO, and the aggregate compartment, AO. In turn, command compartment would be split into a pressurized cabin and the unpressurized upper transfer section.


Command Compartment of the VA vehicle (INSIDER CONTENT)

By 2020, the cosmonaut cabin structure was drastically redesigned to adopt it to new systems and to reduce its mass. The latest changes went into effect just as the first components of the Orel spacecraft were appearing in metal.


NEW, July 10: Interior of the KO compartment (INSIDER CONTENT)

During the development of the new-generation crew vehicle, Russian engineers had to combine cosmonauts life and work functions into a single habitable volume which was previously divided between descent and habitation modules aboard the Soyuz spacecraft.


Aggregate Compartment, AO (INSIDER CONTENT)

The cone-shaped Return Module, VA, of the Federatsiya spacecraft is structurally subdivided into two sections: the Command Compartment, KO, containing the cosmonaut cockpit, and the Aggregate Compartment, AO, located below. It contains the soft-landing propulsion system, attitude control thrusters, landing gear and the main heat shield.


Evolution of the Aggregate Compartment, AO, in 2020 (INSIDER CONTENT)

Another major component of the Orel spacecraft that saw major changes in 2020 was the Aggregate Compartment, AO. As a part of the Return Vehicle, VA, the Aggregate Compartment contains a number of critical systems of the spacecraft, such as landing gear and soft-landing engines.

Thermal protection system (INSIDER CONTENT)

In the 2010s, Russian engineers drastically redesigned the thermal protection system of the crew module of the next-generation spacecraft, just in time for starting experimental manufacturing.


Propulsion Module, DO

The expendable propulsion module, known in Russian as Dvigatelny Otsek or DO, of the PTK spacecraft was designed to accommodate the ship's propulsion system, including a dual main engine and eight clusters of attitude control and orientation engines, DPOs, distributed around the module.


NEW, Sept. 26: Evolution of the DO module design (INSIDER CONTENT)

After its original design completed in 2013, the Propulsion Module, DO,of PTK spacecraft evolved significantly during the 2010s, first of due to drastic changes in the propulsion system.


Landing profile

The defining feature of Russia's new-generation PTK spacecraft would be its landing system. Due to the political requirement to land future manned missions in Russia, while the spacecraft would barely overfly south of the country, a lot of maneuverability was required from the descent module. At the same time, tough deadlines imposed for the development of the vehicle and limited funds, did not leave time for radically innovative solutions.


Landing Solid-propellant Propulsion Unit, PTDU (INSIDER CONTENT)

The Return Module, VA, of the PTK Federatsiya spacecraft was originally designed to land under rocket power. Although parachutes were eventually added to the landing system, the solid propellant motor could still give the crew capsule unique maneuvering capabilities during braking in the final moments before the touchdown.


New landing propulsion system for PTK Federatsiya spacecraft (INSIDER CONTENT)

Taking into account a switch to Baikonur launches, RKK Energia revisited the use of more traditional landing engines, which had been in use on the Descent Module of the Soyuz spacecraft for decades. Moscow-based MKB Iskra, which developed the landing engine, studied the idea during 2017 and confirmed that it could modify the existing engines and adapt newly developed thrusters for the new role.


Landing gear, PU

A defining feature of Russia's new-generation PPTS spacecraft would be its landing system. Due to the political requirement to land future manned missions in Russia, while the spacecraft would barely overfly south of the country, a lot of maneuverability was required from the descent module. At the same time, tough deadlines imposed for the development of the vehicle and limited funds, did not leave time for radically innovative solutions.

docking port

Docking port

Unlike the Soyuz, where the docking port is discarded and burns up in the atmosphere along with the habitation module of the spacecraft at the end of each mission, the new-generation PTK spacecraft will carry its docking mechanism on the descent vehicle, VA, which was designed for at least 10 flights.


PTK redesigned for multiple docking ports (INSIDER CONTENT)

In 2018, developers redesigned the next-generation crew vehicle to make possible its visits to the international gateway in the lunar orbit in addition to trips to the Earth's orbiting space station.


Cheget chair: One size fits all

Russia's veteran Soyuz spacecraft was equipped with Kazbek cosmonaut chairs. Each Kazbek required a custom-made seat liners uniquely molded to the body size of each individual cosmonaut. Not surprisingly, developers of PTK NP hoped to do away with custom-built components, replacing them with a reusable seat that could be adjusted to any member of the cosmonaut corps, a foreign astronaut or a space tourist.


Thermal Control System (INSIDER CONTENT)

The Thermal Control System, SOTR, of the PTK Orel spacecraft derived from the extensive experience in the development and operation of previous technologies for the Soyuz spacecraft. Aboard Orel, SOTR had to perform similar functions, but due to drastically different size and architecture of the two vehicles, the new-generation SOTR system needed a different design and more capabilities.


Rus-M: A new rocket for a new ship

One of the challenges Russian designers faced in developing the next-generation spacecraft in the first decade of the 21st century was the need for a new rocket to launch it. Since the future ship replacing Soyuz would have to carry six instead of three crew members and weigh from 12 to 23 tons, it would need much larger launch vehicle than existing Soyuz rocket capable of carrying just seven tons to the low-Earth orbit.


From Rus-M to Angara-5P

The Angara's role as a carrier of manned spacecraft finally become official, after funding foes had killed the development of the competing Rus-M rocket in 2011. By that time, the Russian government had already launched the construction of a new cosmodrome in the Russian Far East and the Angara-5 rocket was promised a launch pad there.

var4 Super-heavy to the Moon

With the decision of the Russian space agency in 2012 to give priority to lunar missions, a super-heavy launch vehicle would be needed to carry PTK NP into deep space. In the following years, the Russian industry studied numerous architectures of the super rocket.



In 2017, Roskosmos dropped plans to launch the Earth-orbiting version of the next-generation spacecraft on the modified Angara-5 rocket and instead opted for the yet-to-be developed Soyuz-5 booster conceived within the Feniks and Sunkar projects.

Flight 2

Cost of the PTK-ROS system (INSIDER CONTENT)

One of the major obstacles to repurposing the PTK Orel project from the lunar exploration program to the space station objectives was the very high cost of the newly proposed architecture. In particular, the developers faced the very low bar, in terms of price, set by the highly economical and well-optimized Soyuz-MS/Soyuz rocket and spacecraft system, which was hard to match, first of all due to the higher cost of the Angara-5 rockets.


Manufacturing Soyuz replacement (INSIDER CONTENT)

As the first components of the PTK Orel spacecraft began appearing in metal at the end of the 2010s, its was finally time to prepare the production and assembly line for Russia's new-generation spacecraft. In a tradition going back to Gagarin's Vostok, the Orel spacecraft would be put together inside the walls of the Experimental Machine-building Plant, ZEM, in what is now the city of Korolev, north-east of Moscow.


Welding and milling the Command Compartment (INSIDER CONTENT)

By 2023, three fully assembled crew cabins, known as Command Compartment, KO, intended for Russia's next-generation transport vehicle, appeared on the assembly floor in Korolev. They were a part of a much larger batch of at least seven crew capsules, which had to be manufactured in the course of the spacecraft development. However, welding and milling involved in the process posed serious problems for the industry.


Production from composite materials (INSIDER CONTENT)

The next-generation crew vehicle involved unprecedented amount of composite materials, requiring the Russian space industry to master new manufacturing, testing and quality control processes, along with training a cadre of highly qualified specialists.


NEW, June 3: Processing complex for Angara payloads and PTK spacecraft (INSIDER CONTENT)

The planned introduction of the new-generation crew vehicle, PTK Orel, will mark the historic shift of the Russian piloted space flight from Baikonur Cosmodrome, in Kazakhstan, to the Vostochny spaceport, where a dedicated processing facility will have to be built.


Test flight program

By 2013, various sources enabled to compile an emerging picture of the flight test program aimed to validate the PTK NP spacecraft for piloted missions. At the time, all initial test flights were expected to originate in Baikonur.


First phase of ground tests (INSIDER CONTENT)

As the next-generation crew vehicle was finally leaving the drawing board in 2019, the developers were also finalizing an extensive ground testing program to validate numerous technical capabilities of the future spacecraft before it could reach the launch pad no earlier than the end of September 2023.


Orbital flight of the first prototype (INSIDER CONTENT)

To meet the June 7, 2017, presidential order for the start of PTK flight tests in 2022, developers added the launch of a simplified prototype into the test flight program. The official schedule (No. 25-pl) for the development of the PTK system, which included the mission, was issued on Feb. 20, 2018.


New test launch proposed for next-generation spacecraft (INSIDER CONTENT)

In 2019, the developers formulated a scenario for an additional test flight which has to precede launches of the future spacecraft with cosmonauts onboard. As in the test program of NASA's Orion spacecraft, the new Russian transport system would have to demonstrate safe operation of its emergency escape rockets in real flight before the vehicle could be certified to carry a crew.


Ground tests to continue after first launch of Soyuz replacement (INSIDER CONTENT)

To save time in preparation for the first launch of the new-generation crew vehicle, Roskosmos decided to push a series of the most complex ground tests of the future spacecraft to a period after the politically important inaugural mission. Only the second phase of testing would clear the new ship for carrying cosmonauts.

Flight 2

Second test mission of the PTK Orel spacecraft (INSIDER CONTENT)

In 2019, Roskosmos began planning for the second unpiloted test mission of the Orel new-generation spacecraft aiming the rendezvous and docking with the International Space Station.


A test mission behind the Moon

According to a flight scenario evaluated in 2013, a Proton rocket would launch a Block DM space tug into the low Earth orbit. The second Proton would launch an unmanned test version of the PTK NP spacecraft. The two vehicles would then rendezvous and dock in orbit. The Block DM upper stage would then fire its engine sending the spacecraft toward the Moon.

PTK variants


In mid-2022, Russian engineers came up with the concept of a multi-functional space station delivery spacecraft based on the design of the PTK Orel crew vehicle originally developed for lunar flights.



In early 2022, Russian engineers evaluated the possibility of scaling down their prospective lunar crew vehicle into a transport for a future Earth-orbiting space station. The effort focused on the preparation for the transitioning of the Russian space program from an International Space Station to a national outpost in low orbit.


Lighter lunar crew vehicle, PTK-M Orlyonok (INSIDER CONTENT)

By the end of 2020, funding cuts in the Russian space program made it clear that the super-heavy rocket would not be able to leave the drawing board in the foreseeable future, pushing the project well into the 2030s. As a result, Roskosmos decided to take another look at whether it would be possible to send expeditions to the Moon using smaller rockets and spacecraft.


Design of PTK-M variant (INSIDER CONTENT)

In 2020, the Russian space industry has begun drafting the architecture of the PTK-M Orlyonok ("eaglet") crew vehicle which would be a lighter version of the original PTK Orel spacecraft intended for delivering cosmonauts into the lunar vicinity.


DDU propulsion unit for PTK-M variant (INSIDER CONTENT)

The proposed shift of the Russian next-generation crew vehicle from the super-heavy rocket to the Angara family required developing a new space tug to perform various maneuvers during lunar expeditions. Preferably, such a booster would use off-the-shelf hardware to minimize the development time and cost. At least two possible candidates were considered for the role.


Briz-L space tug for PTK-M variant (INSIDER CONTENT)

In 2020, the venerable space tug from Proton-M and Angara rockets was eyed by Russian space strategists for a crucial role in the nation's prospective lunar exploration program, as an upper stage for Orlyonok.


PTK-Z: Echo of Soyuz

In October 2010, Russian space agency, Roskosmos, published its requirements to the industry for the development of the Technical Project of the next-generation spacecraft, PTK NP. The document identified two versions of the spacecraft, which would be a priority for the Technical Project in the next two years. First of these two variants was a three-module PTK-Z spacecraft. It was designed for long-duration autonomous missions in the Earth orbit.