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Jan. 6, 2021
At the Research Center of the Rocket and Space Industry (NRC RCP, part of the State Corporation "Roscosmos") in the city of Peresvet, Moscow Region, successful firing bench tests of the second stage of the Angara-1.2 launch vehicle took place. Thus, one of the final stages of ground testing of a light carrier has been completed. In an interview with the industry magazine of the State Corporation Roscosmos, Russian Space, Nikolai Sizyakov, Director General of the Research Center of the RCP, told how the tests were carried out.
The Angara family includes light and heavy launch vehicles with payloads ranging from 3.5 tons (Angara-1.2) to 38 tons (Angara-A5V) in low-earth orbit. The design of all missiles is based on the so-called universal missile modules (URM), which play the role of a kind of building blocks. They are of two types: URM-1 and URM-2. Thus, the first stage of the light "Angara-1.2" includes one URM-1. And the first stage of the heavy "Angara-A5" already consists of four URM-1, another URM-1 plays the role of the second stage, and the third stage includes one URM-2.
The first experimental launch of a light rocket in the "Angara-1.2PP" modification with an overall and weight model of the spacecraft was successfully completed on July 9, 2014. URM-2 was used as the second stage. Subsequently, they decided to equip the light "Angara" with another second stage, optimal in weight and dimensions, as well as an aggregate module.
Interview:
—Nikolai Petrovich, who was the customer of the tests? Who participated in them? What was the role of the NRC RCP?
- NITs RCP - the industry's leading enterprise for testing rocket technology. The direct customer of the firing bench tests was the Khrunichev Center. Specialists from the Salyut Design Bureau (KB) (a branch of the Khrunichev Center, part of the Roscosmos State Corporation) and the Chemical Automatics Design Bureau (KBKhA, part of the Roscosmos State Corporation) also took part in the work.
- What was the purpose of this stage of testing?
- The tests had several goals. Since the second-stage engines of the standard "Angara-1.2" and the experimental "Angara-1.2PP" are almost identical, but the design of the tank compartment is different, then first of all it was necessary to check and confirm the operability of the pneumohydraulic system. It was also necessary to make sure that the processes occurring in the system before starting and after stopping the engine were in accordance with the design.
In addition, the operations of filling the stage with propellants and compressed gases were tested, and the efficiency of the stage thermostating was confirmed. The completeness and quality of design and operational documentation, manufacturing technology, correct choice of control methods for test equipment and measuring instruments, elements of standard ground equipment, etc. were checked.
In total, 23 specific tasks were solved during the tests. To this end, the specialists of the RPC RCP created operating modes at the stand equivalent to real conditions.
- How long did it take to prepare these tests?
- It all started a long time ago. In 1994, a project was launched to create a modular launch vehicle "Angara". In 2004, the Khrunichev Center issued us a technical assignment for development work on the "Angara" theme, on the basis of which a project was issued for the modernization of the IS-102 test bench for the URM-1 and URM-2 modules.
In 2007, NRC RCP began preparations for bench tests of the URM-1: we adopted a fitting model (in fact, the same rocket unit, but adapted for ground checks, and not for flight. - Ed.), On which the connection of the module's electrical and pneumatic hydraulic systems and a stand. The latter is designed to work with different stages, and most of the interfaces are adjusted for a specific product before each test. The mock-up also tested the means of thermostating and fire safety of the stage - the possibility of the upcoming "burning" depends on their serviceability.
Then the URM-1 model was dismantled. In September 2008, a test copy of the URM-2 was received at the SIC RCP, and in December 2008 - the URM-1. During 2009, two cold (without turning on the engine. - Ed.) And three fire bench tests of the URM-1 took place, and in 2010, four cold and one fire tests of the URM-2.
These works made it possible to carry out flight tests of the experimental "Angara-1.2PP" and perform the first launch of the "Angara-A5". Since the concept of the lightweight "Angara-1.2" has changed during the design process, in 2013 our company entered into an agreement with the Khrunichev Center for testing a new second stage.
The product was delivered to the SIC RCP only in October 2019 and was prepared according to the same scheme as the URM-1 and URM-2 modules. Before cold bench tests in the period from June 27 to July 6, 2020, thermostatting and fire safety equipment were checked, and on July 8 and 9, 2020 - bench tests of the pneumohydraulic stage system. They experimentally confirmed the calculated parameters of the systems, as well as the efficiency of nitrogen and air purging of "dry" (not filled with fuel. - Ed.) Stage compartments.
Three cycles of cold bench tests, which took place in the summer of 2020, provided for pouring the stage tanks with fuel components (including with sequential refueling and simultaneous draining of fuel and oxidizer through emergency drain lines) and made it possible to confirm the performance of the product's pneumohydraulic system.
—What did the firing bench tests show?
—On October 23, 2020, the new second stage of Angara-1.2 was “tested on fire” at the IS-102 stand. Its engine has completed the entire flight cycle, including the rocking of the combustion chambers to control the thrust vector. The tests were successful.
The positive results confirmed the correctness of the design and technological decisions made by the specialists of the Salyut Design Bureau at the Khrunichev Center, NRC RCP and KBKhA, and the operability of all product systems, and also made it possible to make a decision on the admission of Angara-1.2 to flight design tests.
—Could you tell us more about the stand where the work was done? What happens to the missile unit after testing?
—Direct preparation began in October 2019, when the bench second stage of "Angara-1.2" was delivered to the Research Center of the RCP, passed the incoming control and the required checks in the assembly and testing building. In March 2020, it was installed in the stand.
By June, the stand and the stage were connected through the gas supply lines, as well as through the lines for filling, draining and draining fuel and oxidizer. Then we debugged the fuel and gas supply systems, as well as the bench control system. After the completion of the firing tests, the residual kerosene was removed, and the pneumatic-hydraulic system of the stage was cleaned for safe disassembly at the factory. The step will be removed from the stand and, after the final control, sent to the Khrunichev Center.
—What does the success of the tests carried out mean for the Test Center?
“The overwhelming majority of the stands of our enterprise were created during the period of the heyday of rocketry and astronautics, when the volume of tests was enormous, and the demand for stands for various purposes was high. At that time, we conducted more than two thousand tests per year.
Now that many stands are not required. As a result, there was an underutilization of the bench base. These circumstances made it necessary to reform the experimental base of the NRC RCP. This process has already begun and is in full accordance with the enterprise development program and the plan to improve the efficiency of the work performed. Successful tests of the second stage of "Angara-1.2" confirmed not only the presence of the competencies of the RSC RCP in terms of bench testing of launch vehicles, but also the validity of the enterprise reorganization strategy proposed by the management.
ROSCOSMOS Press Release: https://www.roscosmos.ru/29781/
Russian space: https://www.roscosmos.ru/rkosmos/
Images, Text, Credits: ROSCOSMOS/Orbiter.ch Aerospace/Roland Berga.
Happy Christmas Russia, Orbiter.ch
