The Vostok programme picked short pilots and tested its capsule on dogs first
To fit the cramped Vostok capsule, Soviet cosmonauts could be no taller than 1.75 metres and weigh no more than 72 kilograms. The capsule borrowed from a spy satellite design, the rocket came from a nuclear missile, and even the name Vostok stayed secret until Yuri Gagarin had already flown.
Preparations began in 1959, and Air Force doctors insisted that only military pilots be considered, since they already knew high g-forces and ejection seats. Sergei Korolev, the chief designer, added his own rules: male, aged 25 to 30, and small. About 200 candidates survived interviews before centrifuges and low-pressure chambers whittled them down to 20, a deliberately larger group than NASA's seven. Because the spacecraft flew itself, deep flying experience mattered less; the most seasoned man had 900 hours. Training moved in June 1960 to the site later called Star City, still the home of Russian cosmonaut training.
Six men were chosen for fast-track work on the only simulator, reportedly the shortest of the group. Two were soon replaced after injuries in a centrifuge run and a diving accident. Final exams in January 1961 placed Gagarin first, with Gherman Titov second, a verdict his peers shared.
Uncrewed flights came first, under the cover name Korabl-Sputnik, satellite-ship. The first, in May 1960, misfired its thrusters and climbed higher instead of coming down. In July a launch explosion killed the dogs Chayka and Lisichka. Then in August Belka and Strelka spent 26 hours in orbit with mice and insects and came back healthy, the first living creatures recovered from orbit. Later that year another pair was lost when a capsule was deliberately destroyed after misfiring over foreign territory, and in December a failed launch left Kometa and Shutka stranded 3,500 kilometres away in minus 40 degree cold; rescuers found both alive. A separate rocket explosion that October, the Nedelin disaster, killed over 100 people and pushed the schedule back.
Six crewed flights followed between 1961 and 1963. The longest lasted nearly five days, and the last four went up in pairs a day apart, well beyond what Project Mercury had shown. Two Voskhod flights with modified capsules came next.
Source: Vostok programme
