III.

Missions

Vostok capsules were the first spacecraft to carry humans into space. The USSR tested the design of the Vostok capsule on flights with dogs, mannequins, and scientific instruments as passengers. All of the piloted Vostok missions were successful, helping the USSR win a major battle in the space race.

A.

Unpiloted Missions

Korolyev's engineers tested the Vostok capsule under the Korabl-Sputnik program. On May 15, 1960, Korabl-Sputnik 1 reached orbit. All went as planned until just before the retrorocket fired, when controllers discovered that the spacecraft was pointed away from Earth. When it fired its retrorocket it climbed to a higher orbit instead of heading toward Earth. The spacecraft dropped out of orbit naturally and burned up in 1965.

Korabl-Sputnik 2 was launched on August 19, 1960, and was a successful flight by two dogs, Belka and Strelka. By contrast, Korabl-Sputnik 3—launched on December 1, 1960—was intentionally destroyed after its retrorocket shut down prematurely. The capsule probably would have landed safely, but it would have missed the USSR and landed in foreign territory. The dogs onboard, Pchelka and Mushka, were killed.

Korabl-Sputnik 4, launched on March 9, 1961, was the first Vostok capsule designed exactly as it would be for piloted flight. Chernushka, the dog aboard, landed safely after one orbit. On Korabl-Sputnik 5, launched on March 25, 1961, a dog named Zvezdochka rode in the capsule as it landed, while a mannequin wearing the Vostok program's Sokol pressure suit ejected before landing. Zvezdochka survived the landing and the Sokol suit performed well.

B.

Piloted Missions

On April 12, 1961, with a shout of 'Poyekhali!' (“Let’s go!”) 27-year-old Yuri Gagarin lifted off from the USSR for a 108-minute, one-orbit flight aboard Vostok 1. All went well during this first piloted spaceflight until the equipment module ejected. By some accounts, the cable bundle linking the module to the capsule failed to detach, causing the two parts of Vostok 1 to tumble wildly about each other. After about 10 minutes they separated, and Gagarin landed safely.

Vostok 2, lasting from August 6 to August 7, 1961, was a 24.3-hour flight by 25-year-old cosmonaut Gherman Titov. During his 17 orbits, Titov became the first human to eat, sleep, and experience sickness while in orbit (see Aerospace Medicine: Space Medicine). Vostok 3 was postponed for a year because Soviet doctors wished to study the physiological effects of spaceflight. Andrian Nikolayev made a 64-orbit flight aboard Vostok 3 from August 11 to August 15, 1962. Vostok 4 was launched on August 12, 1962, while Vostok 3 was still in orbit. The Vostok capsules could not maneuver, but Soviet controllers launched Vostok 4 so that it passed within 6.5 km (4.0 mi) of Vostok 3. Vostok 4 carried cosmonaut Pavel Popovich and landed safely on August 15, 1962.

At almost five days in duration, Vostok 5 remains the longest solo space mission ever. Valeri Bykovskii flew alone for 81 orbits and 3 million km (2 million mi) from June 14 to June 19, 1963. Valentina Tereshkova became the first woman in space when she flew aboard Vostok 6 from June 16 to June 19, 1963. On its first orbit, Vostok 6 passed within 5 km (3 mi) of Vostok 5. Tereshkova flew on for 2 days 22 hours, covering 1.9 million km (1.2 million mi) in 48 orbits. Soviet engineers planned a Vostok 7 flight that would last a week, but this was canceled so they could concentrate on the Vostok's successor, the Voskhod spacecraft (see Voskhod Program).