Launch from the Baikonur Cosmodrome and
landing 120 km northwest of Karaganda.
The
first manned space
station was launched on April 19, 1971.
Salyut 1 included a number of military experiments,
including the OD-4 optical visual ranger, the Orion ultraviolet instrument for
characterizing rocket plumes, and the highly classified Svinets radiometer.
Primary objectives included photography of the earth, spectrographs of the
earth's horizon, experiments with intense gamma rays, and studying manual
methods for station orientation.
Soyuz 10 approached to 180 m from
Salyut 1 automatically. It was hand docked after
failure of the automatic system, but
hard docking could not be achieved
because of the angle of approach. Flight analysis indicated that the cosmonauts
had no instrument to provide the angle and range rate data necessary for a
successful manual docking.
Soyuz 10 was connected to the station for 5 hours and
30 minutes. Despite the lack of hard dock, it is said that the crew were unable
to enter the station due to a faulty hatch on their own spacecraft.
When
Vladimir
Shatalov tried to undock from the
Salyut, the jammed hatch impeded the docking
mechanism, preventing undocking. After several attempts he was able to undock
and land.
Only a night landing on Soviet territory was possible, which
meant the spacecraft could not be oriented for retrofire. The landing
commission started planning for an emergency landing in South America, Africa,
or Australia. But Vladimir
Shatalov reported the gyroscopes and orientation sensors were
functioning well. He proposed that he orient on the dayside, spin up the gyro
platform, and let the gyros orient the spacecraft on the night side for
retrofire. The plan was followed and the spacecraft was targeted for a landing
area 80-100 km southwest of Karaganda.
So, it was the first night landing in
the history of human spaceflights.
The
Soyuz spacecraft is composed of three elements
attached end-to-end - the Orbital Module, the Descent Module and the
Instrumentation/Propulsion Module. The crew occupied the central element, the
Descent Module. The other two modules are jettisoned prior to re-entry. They
burn up in the atmosphere, so only the Descent Module returned to Earth.
The
deorbit burn lasted 188 seconds. Having shed two-thirds of its mass, the
Soyuz reached Entry Interface - a point 400,000 feet
(121.9 kilometers) above the Earth, where friction due to the thickening
atmosphere began to heat its outer surfaces. With only 23 minutes left before
it lands on the grassy plains of central Asia, attention in the module turned
to slowing its rate of descent.
Eight minutes later, the spacecraft was
streaking through the sky at a rate of 755 feet (230 meters) per second. Before
it touched down, its speed slowed to only 5 feet (1.5 meter) per second, and it
lands at an even lower speed than that. Several onboard features ensure that
the vehicle and crew land safely and in relative comfort.
Four parachutes,
deployed 15 minutes before landing, dramatically slowed the vehicle's rate of
descent. Two pilot parachutes were the first to be released, and a drogue chute
attached to the second one followed immediately after. The drogue, measuring 24
square meters (258 square feet) in area, slowed the rate of descent from 755
feet (230 meters) per second to 262 feet (80 meters) per second.
The main
parachute was the last to emerge. It is the largest chute, with a surface area
of 10,764 square feet (1,000 square meters). Its harnesses shifted the
vehicle's attitude to a 30-degree angle relative to the ground, dissipating
heat, and then shifted it again to a straight vertical descent prior to
landing.
The main chute slowed the
Soyuz to a descent rate of only 24 feet (7.3 meters)
per second, which is still too fast for a comfortable landing. One second
before touchdown, two sets of three small engines on the bottom of the vehicle
fired, slowing the vehicle to soften the landing.
During the landing,
the
Soyuz air supply became toxic, and Nikolai
Rukavishnikov (much like the case of Vance
Brand
during the Apollo
ASTP return) was
overcome and became unconscious.