--- title: "Space Cargo Ship 'Progress MS-35' Successfully Passes Critical Leak-Tightness Tests at Baikonur" description: "🚀 'Progress MS-35' passes leak-tightness check at Baikonur! 🌌 The space cargo ship successfully withstood tests in a vacuum chamber simulating space. This is the 96th joint launch to supply the ISS. The flight is being prepared for launch! 🛰️🇷🇺" date: 2026-08-11T22:41:26.000Z lang: en url: https://xab.info/en/posts/progress-ms-35-leak-tightness-tests-baikonur-2026 tags: [progress-ms-35, bayanour, iss-supply, space-exploration, cosmonautics] publisher: "XAB.info" --- # Space Cargo Ship 'Progress MS-35' Successfully Passes Critical Leak-Tightness Tests at Baikonur ![Progress MS-35 cargo spacecraft on the test stand in the assembly shop of Baikonur before hermeticity check](https://xab.info/media/2026/08/11/progress-ms-35-ispytaniya-na-germetichnost-baykonur-2026/progress-ms-35-ispytaniya-na-germetichnost-baykonur-2026-1.webp) ## 🎯 Key Points - The cargo spacecraft 'Progress MS-35' successfully passed leak-tightness tests in a vacuum chamber at Baikonur. - Tests began at the beginning of the previous week and concluded positively, confirming the reliability of the spacecraft's systems. - The launch will be the 96th joint step within the ISS supply program. - Currently, engineers have connected the spacecraft to ground equipment for further launch preparation. At the Baikonur Cosmodrome, one of the key stages of preparation for the launch of the Progress MS-35 cargo spacecraft has been completed. In early August 2026, the spacecraft successfully underwent comprehensive leak-tightness tests, which are a mandatory requirement for flight clearance. This procedure, initiated at the beginning of the previous week, proceeded in a standard mode, confirming the reliability of the life support systems and the structural integrity of the spacecraft. ### Simulating Open Space Conditions To conduct the inspection, specialists placed the 'Progress MS-35' into a special vacuum chamber located in the assembly and test building. This equipment allows for the full simulation of open space conditions, creating the necessary vacuum and temperature regimes. During the tests, gas was supplied through special pipelines to all compartments and lines of the spacecraft. Engineers carefully monitored the pressure to ensure the absence of leaks and the tightness of all docking nodes. After the successful completion of the procedure, the spacecraft was returned to its standard work station. ### Preparation for the 96th Joint Launch According to data provided by program representatives, the upcoming launch will be the 96th joint step within the mission to supply the International Space Station (ISS). This underscores the strategic importance of this flight for maintaining the uninterrupted operation of the orbital laboratory. Currently, after returning from the vacuum chamber, engineers have connected the spacecraft to ground test equipment. Specialists have begun the next phase of preparation, which includes checking on-board systems and integration with the launch vehicle. ### Significance of Tests for Flight Safety Experts emphasize that successfully passing leak-tightness tests creates a fundamental basis for the safe and stable conduct of the upcoming launch. Tests in a vacuum chamber allow for the detection of potential defects that may only manifest under conditions of weightlessness and a rarefied atmosphere. Guaranteeing tightness is critically important not only for the preservation of the spacecraft itself but also for ensuring the safety of the cargo it will deliver to the station, including fuel, water, food, and scientific equipment. ### Contradictory Data During the fact-checking of information regarding the timing of the tests, minor discrepancies were found in the wording of various sources. The publication ixbt.com reports that the process began 'at the beginning of the previous week' (relative to the publication date of August 11), indicating that work began in the period from August 1 to 7. At the same time, other news summaries (Rambler News) mention that the check took place 'in early August' without specifying exact start dates. However, these differences are purely editorial in nature and do not affect the confirmed fact of the successful completion of the tests by August 11, 2026. ## 🔍 Fact-Check Verification - [Space cargo ship "Progress MS-35" passed leak-tightness tests](https://news.rambler.ru/tech/56890815-kosmicheskiy-gruzovik-progress-ms-35-proshel-ispytaniya-na-germetichnost/) - Подтверждает факт испытаний и их успешное завершение. - [Space cargo ship "Progress MS-35" passed leak-tightness check](https://news.rambler.ru/tech/56890862-kosmicheskiy-gruzovik-progress-ms-35-proshel-proverku-na-germetichnost/) - Подтверждает факт испытаний и их успешное завершение. - [Space cargo ship "Progress MS-35" tested for leak-tightness](https://www.ixbt.com/news/2026/08/11/kosmicheskij-gruzovik-progress-ms35-ispytali-na-germetichnost.html) - Источник подтверждает успешное прохождение испытаний и начало процесса в начале прошлой недели. - [Soon to be sent to ISS: "Progress MS-35" will be checked in space conditions before launch](https://www.ixbt.com/news/2026/08/04/426441-skoro-otpravka-na-mks-progress-ms-35-proveriat-v-usloviiax-kosmosa-pered-zapuskom.html) - Источник подтверждает успешное прохождение испытаний и начало процесса в начале прошлой недели. ## ❓ FAQ ### Q: Where were the 'Progress MS-35' tests conducted? **A:** The tests were conducted at the Baikonur Cosmodrome in a special vacuum chamber of the assembly and test building. ### Q: What is the purpose of the leak-tightness tests? **A:** The goal is to simulate open space conditions and check for the absence of leaks in the spacecraft's compartments and lines before launch. ### Q: How many launches is this in the ISS supply program? **A:** This launch will be the 96th joint step within the International Space Station supply program.