The chief designer of the Volga inflatable airlock that made Leonov's spacewalk possible
On 18 March 1965, Alexei Leonov opened the hatch of the Volga airlock after it had inflated in orbit and stepped into space.
Boris Mikhailov was the chief designer at Engineering Plant 918 (later NPO Zvezda) in Tomilino near Moscow, where in mid-1964 he led the team that designed, built, and tested the Volga inflatable airlock in just nine months. A metal airlock would not fit the Voskhod spacecraft, so his flexible structure, folded for launch and inflated on orbit, was the only solution. On 18 March 1965, Alexei Leonov walked into space through this airlock in humanity's first spacewalk.
Activities and affiliations
Career Timeline
- 1964–1965Chief Designer of the Volga inflatable airlock, Engineering Plant 918 (Zvezda), Tomilino
Related historical events
Designing the Volga inflatable airlock
The Voskhod-2 spacewalk was not just a matter of one brave cosmonaut but an engineering problem that overturned a basic assumption of spaceflight, that structures had to be metal. Rather than depressurizing the whole cabin as the American Gemini program did, Soviet designers chose to pass through a dedicated airlock, because depressurizing the cabin would have meant rebuilding every piece of equipment to work in a vacuum. The difficulty was where to stow the airlock: a metal cylinder large enough for a man simply would not fit inside the rocket's payload fairing.
The answer was a folding, flexible structure. The Volga airlock, designed at Engineering Plant 918 (later NPO Zvezda) in Tomilino near Moscow, was folded to 1.2 meters in diameter and 74 centimeters long for launch, mounted over the descent module's No. 3 hatch, and then inflated with compressed air in orbit into a 2.5-meter passageway. Its flexible midsection was held by a rubberized double membrane and forty cylindrical inflatable ribs, the 'dutiki', grouped into three independent sections so that a puncture in one would not collapse the others. Because the rigid-metal-airlock idea was abandoned, the spacecraft and its launcher fairing needed only minor changes to acquire spacewalk capability.
The design echoed Konstantin Tsiolkovsky, who had already sketched egress through an airlock in 1898, which is why Sergei Korolev constantly told his engineers to read Tsiolkovsky. The Volga was designed, built, and tested in just nine months from mid-1964, and its sealing was verified in the unmanned Kosmos-57 test flight of 22 February 1965. Although that vehicle self-destructed during reentry, the airlock itself had done its job, and a month later, on 18 March 1965, Alexei Leonov walked into space through it for the first spacewalk in history. After its task was done the airlock was jettisoned before reentry. Of the seven Volga sets built, the unflown examples are preserved today at NPO Zvezda, RKK Energia, and Moscow's Museum of Cosmonautics.