The first series of manned Russian spacecraft. Six Vostok ("East") missions,
from 1961 through 1963, carried cosmonauts on successively longer flights,
and each set a new first in spaceflight history. Vostok 1 was the first
manned spacecraft to complete a full orbit, Vostok 2 the first to spend
a full day in space. Vostoks 3 and 4 comprised the first two-spacecraft
mission. Vostok 5 was the first long-duration mission, and Vostok 6 the
first to carry a woman.
Yuri Gagarin's historic flight was preceded
by a number of unmanned missions to test the space-worthiness of the Vostok
capsule and the reentry and recovery method to be used. These test flights
were known in the west as Sputnik 4, 5, 6, 9, and 10 but in the Soviet Union
as Korabl Sputnik 1–5.
Vostok spacecraft
A spherical cabin, 2.3 m in diameter, attached to a biconical instrument
module. The cabin was occupied by a single cosmonaut sitting in an ejection
seat which could be used if problems arose during launch and was activated
after reentry to carry the pilot free of the landing sphere. Also inside
the cabin were three viewing portholes, film and television cameras, space-to-ground
radio, a control panel, life-support equipment, food and water. Two radio
antennas protruded from the top of the capsule, and the entire sphere was
coated with ablative material so that there was no need to stabilize it
to any particular attitude during reentry. The instrument module, which
was attached to the cabin by steel bands, contained a single, liquid-propellant
retrorocket and smaller attitude control thrusters. Round bottles of nitrogen
and oxygen were clustered around the instrument module close to where it
joined the cabin.
Vostok rocket
Essentially, the same rocket (a modified R-7 ballistic missile; see "R"
series of Russian missiles) that had launched Sputnik 1, 2, and 3, but
with an upper stage supported by a latticework arranged and powered by a
single RD-7 engine. The combination could launch an LEO payload of about
4,700 kg.
Vostok missions
Vostok 1
Launch of Vostok 1
Yuri Gagarin made history with his, 108-minute, 181 × 327-km single-orbit
flight around the world. Once in orbit, he reported that all was well and
began describing the view through the windows. Gagarin had brought a small
doll with him to serve as a gravity indicator: when the doll floated in
midair he knew he was in zero-g. (On Apr. 12, 1991, Musa Manarov, the man
who had by then logged the mmost time in space (541 days) carried the same
doll back into orbit to mark aboard Mir the 30th anniversary of Gagarin's
flight.) Gagarin had no control over his spacecraft: a "logical lock" blocked
any actions he might make in panic because, at the time, little was known
of how humans would react to conditions in space. In case of emergency,
Gagarin had access to a sealed envelope in which the logical lock code was
written. To use the controls he would have had to prove that he was capable
of doing the simple task of reading the combination and punching three of
nine buttons. However, in the event, this proved unnecessary and radio signals
from the ground guided the spacecraft to a successful reentry. At a height
of 8,000 m, Gagarin ejected from his capsule and parachuted to the ground,
southeast of Moscow near the Volga river, some 1,600 km from where he took
off. Official details of the flight were not released until May 30 when
an application was issued to the International Aeronautical Federation (FAI)
to make the flight a world record. Gagarin's midair departure from Vostok
was kept a secret much longer because the FAI required the pilot to return
in his craft in order for the record to be valid. It would be another month
before Alan Shepard made his suborbital flight, and 10 months before John
Glenn became the first American in orbit.
Vostok 2
The first manned spaceflight to last a whole day. The 36-year-old pilot,
Titov, ate some food pastes on his third orbit and later took manual control
and changed the spacecraft's attitude. About 10 hours into the mission,
he tried to catch some sleep but became nauseous – the first of many
space travelers to experience space motion sickness. However, Titov did
eventually fall asleep for over seven hours before waking for a perfect
reentry and landing, 25 hours 18 minutes after launch.
Vostok
3 and 4
The first manned double launch. Vostok 3 and 4 took off from the same launch
pad a day apart and were placed in such accurate orbits that the spacecraft
passed within 6.5 km of each other. No closer rendezvous than this was possible,
however, because the Vostoks were not equipped for maneuvering. The joint
flight continued, with the two cosmonauts, Nikoleyev and Popovitch, talking
to each other and with ground control by radio. Finally, the spacecraft
reentered almost simultaneously and landed just a few minutes apart. <
Vostok 5 and 6
Another double launch, this time involving the first woman in space –
26-year-old Valentina Tereshkova. She returned to Earth after almost three
days in orbit, followed by Valery Bykovsky a few hours later at the conclusion
of a five-day flight that has remained ever since the longest mission by
a single-seater spacecraft.