“The service cabin collapsed into the flame trench.” That was the blunt assessment from independent Russian space analysts after Thursday’s Soyuz MS-28 launch from Baikonur Cosmodrome left the country’s only operational crewed launch pad visibly damaged. This happened during a flight that otherwise went off without issue, sending Russian cosmonauts Sergey Kud-Sverchkov and Sergey Mikaev, together with NASA astronaut Chris Williams, on their way to the International Space Station just over three hours after liftoff.
The damage centers around Site 31/6, a Soviet-era pad constructed in the 1960s and in exclusive use for Soyuz crewed flights since 2019, when the historic Site 1–Gagarin’s Start–was retired from service. Video released by Roscosmos and state media shows the pad’s service bay, or mobile service platform, becoming dislodged as the Soyuz 2.1a’s RD-107A and RD-108A engines ignited. The platform, which houses cabling, instrumentation, and technician access points for the rocket’s base section, fell into the exhaust trench as the launch plume enveloped the structure. Overhead imagery released later by Roscosmos showed the charred remains of the platform lying in the trench, an area engineered to channel exhaust gases away from the pad via reinforced flame ducts and blast deflectors.
Exhaust trenches at heavy-lift pads are designed to sustain extreme thermal and acoustic loads. Soyuz 2.1a, with its four strap-on boosters and a core stage, produces combined thrust of over 4.1 MN at lift-off, while the exhaust temperatures are in excess of 3,000°C. The deflector systems laterally redirect this plume to avoid direct impingement on pad structures, but the violent combination of heat, pressure waves, and vibration nonetheless imposes cyclic fatigue on components in the vicinity. In the present instance, spaceflight observers, including Katya Pavlushchenko, surmised that either structural degradation or failed locking mechanisms may have allowed the platform to collapse, even though it normally retracted before launch.
Roscosmos has minimized the seriousness of the situation, saying only, All the necessary spare components are available for repair, and the damage will be repaired shortly. But experts like Anatoly Zak have countered that repairs to the 8U0216 service platform might take up to two years depending on the extent of structural compromise. If that timeline proves correct, it would force Roscosmos into accelerating modernization at an alternate pad or face serious disruption to crew rotation and cargo logistics.
The unique status of Baikonur composes the engineering challenge. Russia leases the facility from Kazakhstan through 2050, and the complex at Site 31/6 is the sole pad there that’s certified for human spaceflight. The Vostochny Cosmodrome, in Russia’s Far East, remains incomplete for crewed missions, lacking full suites of life-support, emergency egress, and pad integration systems necessary to support Soyuz operations. While Site 1 theoretically could be refurbished, previous plans to renovate it for Soyuz-2 were shelved for lack of funding, and more recently, it has been slated for conversion into a museum.
From a mission safety perspective, the flight of MS-28 was unaffected: the Soyuz spacecraft separated cleanly from the launch vehicle, executed its orbital insertion burns, and docked with the ISS without anomaly. The crew will spend approximately 242 days aboard, executing around 40 experiments and two planned spacewalks. But the damage to ground infrastructure underlines the fragility of Russian human spaceflight access. As Pavel Luzin has noted, “[Recent] emergency cases with Soyuz manned spacecrafts affect the reputation of [the] Russian space industry,” already strained by inefficiencies in economics and concerns over quality in manufacturing.
This failure mode-mechanical collapse of a retracted service platform-is not a common kind of post-launch wear, such as refractory brick spalling or steel frame distortion in the exhaust trench. If the platform anchoring system fails under vibrational loads, that raises questions about inspection intervals, materials fatigue, and whether thermal shielding was adequate against reflected exhaust. Because the platform also routes critical umbilicals during prelaunch, its loss eliminates redundancy in pad servicing capability.
The operational question Roscosmos must now answer is whether to transition missions planned for later this year, like the Progress MS-33 cargo flight, to other infrastructure. With the loss of a second active crew pad, any extended outage cuts into ISS crew rotation. NASA can continue launching its astronauts on SpaceX’s Crew Dragon, but the Russian segment relies on Soyuz to move not only personnel but also Progress to supply propellant and keep the station in orbit.
For now, Roscosmos has initiated a structural assessment of Site 31/6. While the agency insists repairs will be rapid, the visible scale of the collapse and the engineering complexity of replacing a precision-aligned, load-bearing platform within a flame trench suggests the outcome depends very much on whether the damage is superficial or foundational. Until the inspection is complete, the reliability of Russia’s sole human-rated launch site is an open question.
