The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

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An experimental American space station adapted
from Apollo hardware. Skylab consisted of the
orbital workshop itself, an airlock module, a multiple
docking adapter, and the Apollo telescope mount. In
orbit, the station was 36 m long and, with a docked
Apollo command and service module, had a mass of
about 90.6 tons. The living volume was about the
same as that of a small house. Because crews stayed
for one, two, or three months, the orbital workshop
was designed for habitability, with more amenities
than previous spacecraft. Among the features especially
appreciated by crews were a large window for
viewing Earth, a galley and wardroom with a table for
group meals, private sleeping quarters, and a shower,
custom-designed for use in weightlessness.
Twin solar array wing panels were folded against the
orbital workshop for launch, one on each side. When
Skylab reached orbit, the arrays would extend, exposing
solar cells to the Sun to produce 12 kW of power.
Skylab was equipped to observe Earth’s natural
resources and the environment, and activity on the
Sun. Astronauts also studied the effects of long-term
weightlessness on the human body and materials processing
in microgravity, and performed experiments
submitted by students for a “Classroom in Space.”
Because Skylab was a research laboratory, the composition
of the crew differed from that of the Mercury,
Gemini, and Apollo missions. Except for one scientist
on the last Apollo mission, all previous crew members
had been pilots. The Skylab crews included a number
of scientist-astronauts.
Skylab 1
The unmanned mission to place Skylab in orbit. During
launch, on May 14, 1975, the micrometeoroid
shield accidentally deployed too soon, jamming one
solar array wing and damaging the other so badly that
both the wing and the shield were ripped away. Left
with only one solar array wing and no micrometeoroid
shield, which also served as a shade to keep the
interior of the space station cool, Skylab could have
been rendered useless. However, thanks to clever engineering
and improvisation, the effect of the damage
was minimized, and planned Skylab operations were
able to go ahead despite some reduction in power.
Skylab
Skylab 2
The first manned Skylab mission, devoted to starting
up and checking out the space station and, most
importantly, fixing the damage caused during the station’s
launch. With the temperature inside Skylab at a
scorching 52°C, the astronauts’ first priority was to set
up a “parasol” shade as a makeshift replacement for
the lost micrometeoroid shield. Once this had been
deployed by reaching out of Skylab’s main hatch, the
temperature inside the station dropped to comfortable
levels. On the third day of the mission (MD-3),
the crew began turning on experiments. Then, on
MD-14, Conrad and Kerwin went on a crucial threehour
spacewalk to extend Skylab’s only remaining
solar array wing, which was jammed by a strap of
debris. Kerwin was able to cut through the debris
using off-the-shelf barbed-wire snippers that NASA
had bought for just $75. The success of this repair
ensured that there would be enough power for the full
28-day mission and for the subsequent Skylab 3 and
Skylab 4 missions. A couple of days before returning
home, Conrad and Kerwin carried out another spacewalk
to retrieve and replace film from the solar telescopes,
repair a circuit breaker module, and do minor
maintenance on experiment packages located outside
the station. Upon completion of the mission, the Skylab
2 crew briefly set a new manned spaceflight
endurance record, previously held by cosmonauts
Dobrovolsky, Volkov, and Patsayev on Salyut 1 in
June 1971.
Launch: May 25, 1973
Recovery: June 22, 1973
Mission duration: 28 days
Crew: Charles “Pete” Conrad Jr. (commander), Paul
Weitz (pilot), Joseph Kerwin (science pilot)
Skylab 3
The second manned Skylab mission. Shortly after
entering the space station, all three crew members fell
victim to space-sickness, delaying the activation of
onboard equipment. On Mission Day-5, an apparent
failure of two of the four thruster quadrants on the
Command and Service Module (CSM) was detected.