Кеңес Одағының алғашқы пилотты ғарыш кемесі – "Восток" бағдарламасы

First crewed spacecraft built by the Soviet Union
the spacecraft series

Vostok (Восток, translated as "East") was a class of single pilot crewed spacecraft built by the Soviet Union. The first human spaceflight was accomplished with Vostok 1 on April 12, 1961, by Soviet cosmonaut Yuri Gagarin. The Vostok programme made six crewed spaceflights from 1961 through 1963. This was followed in 1964 and 1965 by two flights of Vostok spacecraft modified for up to three pilots, identified as Voskhod. By the late 1960s, these were replaced with Soyuz spacecraft, which are still used as of 2023.

The Vostok spacecraft was originally designed for use both as a camera platform (for the Soviet Union's first spy satellite program, Zenit) and as a crewed spacecraft. This dual use design was crucial in gaining Communist Party support for the program. The basic Vostok design has remained in use for some 40 years, gradually adapted for a range of other uncrewed satellites. The descent module design was reused, in heavily modified form, by the Voskhod program.

Prototype spacecraft. This was used in the Korabl Sputnik 2 mission, in which the first animals were recovered from orbit.

Photo reconnaissance and signals intelligence spacecraft. Later named Zenit spy satellite.

The Vostok capsule had limited thruster capability. As such, the reentry path and orientation could not be controlled after the capsule had separated from the engine system. This meant that the capsule had to be protected from reentry heat on all sides, thus explaining the spherical design (as opposed to Project Mercury's conical design, which allowed for maximum volume while minimizing the heat shield diameter). Some control of the capsule reentry orientation was possible by way of positioning of the heavy equipment to offset the vehicle center of gravity, which also maximized the chance of the cosmonaut surviving g forces while in a horizontal position. Even then, the cosmonaut experienced 8 to 9g. If the retrorocket failed, the spacecraft would naturally decay from orbit within ten days, and the cosmonaut was provided with enough food and oxygen to survive until that time.