Cargo module "Zarya": 20 years in orbit

Specialists of the center. Khrunichev pay attention to the very long life of the functional cargo block "Dawn". This is stated in the article from the collection of theses of the XLIII Academic readings in cosmonautics (pp. 263-265 in the collection ).

“Analysis of the data on the resource consumption of the onboard FGB systems for the reporting period showed that the BR-9TSU-8 telemetry control system is the most critical, its resource has been developed more than 14 times,” the report said. - Therefore, in the FGB, the work of the onboard systems is performed with the inclusion of the recording mode only when performing routine maintenance of the SES and when conducting technical experiments. When performing routine operations, FGB status telemetry is used, which is received through the American segment of the ISS. ”

During 1998–2018 work was carried out to restore the working capacity of the failed onboard equipment. Now a significant part of electronic equipment is far beyond the warranty period or warranty time.

To date, engineers have classified all Dawn equipment into four categories of criticality: “Catastrophic”, “Critical”, “Affects Flight”, “Does Not Affect Flight”) and installed equipment whose failure could cause catastrophic consequences. Software has been developed that allows determining the most preferable FGB equipment replacement procedure on the basis of estimating the parameters of failures and predictions of avalanche-like equipment failures.

20 years ago, the FGB Zarya became the first functional unit on the ISS under construction. About 150 Russian and Ukrainian enterprises participated in its creation and equipment. The FSB was created taking into account the developments on the “Supply Supply Ship” , created under the leadership of Academician V.N. Chelomey, and the modules of the Mir orbital station, while the technical task was repeatedly specified during the design, testing and manufacturing of the module, as new requirements appeared in the process of creating the next MKS modules in order of assembly, which led to the need for improvements in the numerous FGB interfaces with Russian and american segments.

“The FGB certified lifespan expired in November 2013,” the article says. - Considering the progress of the assembly of the station and the condition of the onboard equipment, it was decided to extend the service life until 2020, and later it was decided to extend the flight of the ISS until 2024. Currently, this date is agreed with all the partners of the MKS program. ”

According to the engineers, some of the resources of the Dawn are suitable for use during the entire service life: these are pressurized compartments for placing cargo and fuel reserves in the tanks of the fuel system. Over 20 years of operation, the cargo module has proven its reliability.