Soyuz
A series of manned Russian spacecraft, in use longer than any other; it
is carried into orbit by the Soyuz launch
vehicle. Designed during the Space Race era, Soyuz first carried a cosmonaut
in April 1967. Since then the original Soyuz ("union") craft and
its subsequent generations – the Soyuz T, TM, and TMA – have
flown scores of manned missions. Although modifications have made the spacecraft
more efficient and reliable, the basic structure remains the same.
A Soyuz spacecraft has three main components. The orbital module at the
front is an egg-shaped section, 2.2 x 2.7 m, that provides space for the
cosmonauts to work in once they are in space. The descent module in the
middle is a bell-shaped section, about 2.2 m long and 2.2 in diameter, in
which the cosmonauts sit during launch and upon their return to Earth. The
instrument module at the back is cylindrical and measures 2.7 m wide and
2.3 m long. As the spacecraft evolved, more efficient electronics and navigation
systems were added and the landing module interior was rearranged to make
it more spacious. A version of Soyuz is being used as a crew rescue vehicle
serving the International Space Station.
| Versions of the Soyuz spacecraft |
| name |
first flown |
notes |
| Soyuz 1-9 |
1967 |
Up to three cosmonauts without spacesuits |
| Soyuz 10-11 |
|
Addition of docking module |
| Soyuz 12-40 |
1973 |
Limit of two spacesuited cosmonauts + equipment to
Salyut |
| Soyuz T |
1979 |
Longer-duration vehicle to carry three spacesuited
cosmonauts to space station |
| Soyuz TM |
1986 |
Further refinement to serve the Mir space station |
| Soyuz TMA |
1997 |
"Lifeboat" for International Space Station |
History
The manned Soyuz spacecraft was originally conceived by Sergei Korolev
in 1961 as a component of the "Soyuz complex" that also included unmanned
booster modules and orbiting fuel tankers and was geared toward a manned
mission to the Moon (see Russian
manned lunar programs). When this plan was abandoned, only the crewed
vessel remained: its new primary task that of a space station ferry.
Soyuz 1-9
 |
Soyuz 1 |
The first version of Soyuz could accommodate three cosmonauts in the cramped
descent module, but only if spacesuits were not worn. Power was provided
by a pair of solar arrays on either side of the instrument module which
were folded during launch. Once in space the crew could enter the orbital
module to conduct experiments. This module could also be depressurized to
serve as an airlock for cosmonauts to perform
spacewalks. Although the forward section of the orbital module did have
provision for docking to another Soyuz, there was no connecting hatch so
that crew exchanges could only be accomplished by spacewalks. At the end
of the flight the crew returned to the descent module which was equipped
with a heat-shield, separated from the other two modules, and reentered.
The descent was slowed by a single large parachute and, just 2 m above the
ground, by four small rocket motors on the capsule's base.
After several unmanned tests, the first Soyuz was launched on Apr. 23, 1967,
at 3:35 a.m. local time – the first night launch of a crewed vehicle
– with pilot Vladimir Komarov on board. Once in orbit it was to have
served as a docking target for Soyuz 2 and its crew of three. After the
docking, the two engineers were to have transferred to Soyuz 1 and returned
home with Komarov. However, Soyuz 2 was never launched because of a problem
with Soyuz 1 in orbit. After just over a day in space and several failed
deorbit attempts, Soyuz 1 successfully reentered the atmosphere but then
crashed to the ground after its parachute lines became tangled, killing
Komarov. Although there had been a catalogue of shortcomings with Soyuz
before launch, Soviet premier Brezhnev wanted a spaceflight to commemorate
the 50th anniversary of the Communist revolution. Cosmonauts had prepared
a document listing 200 technical problems and gave it to high-ranking officials.
Yuri Gagarin, the first person in space
and backup pilot for Soyuz 1, also tried unsuccessfully to convince Brezhnev
to cancel the launch. Both Komarov and Gagarin, who were good friends, knew
that the pilot of Soyuz 1 would be in great danger. A few weeks before launch,
Komarov said, "If I don't make this flight, they'll send the backup pilot
instead. That's (Yuri), and he'll die instead of me." Following the accident,
Gagarin said, "... if I ever find out he (Brezhnev) knew about the situation
and still let everything happen, then I know exactly what I'm going to do."
Rumor has it that Gagarin did eventually catch up with Brezhnev –
and threw a drink in his face. A successful crew exchange first took place
on a later mission. Three cosmonauts were launched on Soyuz 5 (Boris Volynov,
Alexei Yeliseyev and Yevgeni Khrunov), and one aboard Soyuz 4 (Vladmir Shatalov).
For the trip back, Yelisyev and Khronuv switched to Soyuz 4 thus becoming
the first humans to return to Earth in a craft other than the one in which
they were left. Soyuz 10 and 11
Three-man missions involving a Soyuz modified by the removal of large fuel
tank at the rear of the instrument module (not needed with the abandonment
of the Moon plan) and the addition of a new docking system with a hatch
to allow cosmonauts to transfer to a space station without a spacewalk.
Soyuz 10 briefly docked with Salyut 1. Soyuz 11 docked with the station
normally but its crew was killed during reentry when a valve opened suddenly
and allowed all the air in the descent module to escape. The cosmonauts,
who wore no pressure suits, died apparently before they had realized what
was happening. Soyuz 12-40
Shocked by the catastrophe of Soyuz 11, Soviet engineers overhauled the
Soyuz spacecraft to increase safety. Never again would cosmonauts go to
and from orbit without pressure suits. To make room for the emergency life-support
system needed for the suits, the standard Soyuz crew was reduced from three
to two. There were no more fatalities in the program; however, Lazarev and
Makarov, aboard Soyuz 18-1, had a lucky escape after half the explosive
bolts holding the first and second stages of their Soyuz booster together
failed to blow. Forced to abort the launch, they suffered a harsh reentry
from 140 km up before their capsule hit a mountain near the Chinese border,
rolled down side, and left the crew to spend a day huddled round a fire
waiting for rescue. The most famous of the Soyuz missions in this period
was Soyuz 19 which took part in the Apollo-Soyuz
Test Project. Soyuz T
First flown in December 1979, the T was equipped with more compact electronics
which enabled the descent module to hold three spacesuited cosmonauts. It
also carried solar panels – a feature of early Soyuz spacecraft that
had been dispensed with after Soyuz 11 to save weight-enabling the vehicle
to function independently of Salyut for up to four days.
Soyuz TM
A modernized version of the T with improved power supplies, new parachutes,
and extra space for equipment. It can carry an extra 200 kg into orbit and
return up to 150 kg to Earth – 100 kg more than Soyuz T. First used
with Mir, it remain in service ferrying cosmonauts, astronauts, and freight
to and from the ISS. Soyuz TMA
 |
Soyuz TMA-6 spacecraft approaching
the ISS |
A specially adapted version of the Soyuz spacecraft to serve as an lifeboat
for crew return to Earth in the event of an emergency aboard the ISS.
Related category
• MANNED
SPACEFLIGHT
Also on this site: Encyclopedia
of Alternative Energy & Sustainable Living
Encyclopedia
of History
BACK TO TOP
|