s called
STS-107. It would be the 28th flight of Columbia.
While the STS-107 mission will likely be remembered most
for the way it ended, there was a great deal more to the
dedicated science mission than its tragic conclusion. The
planned microgravity research spanned life sciences, physi-
cal sciences, space and earth sciences, and education. More
than 70 scientists were involved in the research that was
conducted by Columbias seven-member crew over 16 days.
This chapter outlines the history of STS-107 from its mis-
sion objectives and their rationale through the accident and
its initial aftermath. The analysis of the accidents causes
follows in Chapter 3 and subsequent chapters.
2.1 M
ISSION
O
BJECTIVES

AND
T
HEIR
R
ATIONALES
Throughout the 1990s, NASA flew a number of dedicated
science missions, usually aboard Columbia because it was
equipped for extended-duration missions and was not being
used for Shuttle-Mir docking missions or the assembly of
the International Space Station. On many of these missions,
Columbia
carried pressurized Spacelab or SPACEHAB
modules that extended the habitable experiment space avail-
able and were intended as facilities for life sciences and
microgravity research.
In June 1997, the Flight Assignment Working Group at John-
son Space Center in Houston designated STS-107, tentatively
scheduled for launch in the third quarter of Fiscal Year 2000, a
research module flight. In July 1997, several committees of
the National Academy of Sciences Space Studies Board sent
a letter to NASA Administrator Daniel Goldin recommend-
ing that NASA dedicate several future Shuttle missions to
microgravity and life sciences. The purpose would be to train
scientists to take full advantage of the International Space
Stations research capabilities once it became operational,
and to reduce the gap between the last planned Shuttle science
mission and the start of science research aboard the Space
Station.
1
In March 1998, Goldin announced that STS-107,
tentatively scheduled for launch in May 2000, would be a
multi-disciplinary science mission modeled after STS-90, the
Neurolab mission scheduled later in 1998.
2
In October 1998,
the Veterans Affairs and Housing and Urban Development
and Independent Agencies Appropriations Conference Re-
port expressed Congress concern about the lack of Shuttle-
based science missions in Fiscal Year 1999, and added $15
million to NASAs budget for STS-107. The following year
the Conference Report reserved $40 million for a second sci-
ence mission. NASA cancelled the second science mission in
October 2002 and used the money for STS-107.
In addition to a variety of U.S. experiments assigned to
STS-107, a joint U.S./Israeli space experiment the Medi-
terranean-Israeli Dust Experiment, or MEIDEX was added
to STS-107 to be accompanied by an Israeli astronaut as
part of an international cooperative effort aboard the Shuttle
similar to those NASA had begun in the early 1980s. Triana,
a deployable Earth-observing satellite, was also added to the
mission to save NASA from having to buy a commercial
launch to place the satellite in orbit. Political disagreements
between Congress and the White House delayed Triana, and
the satellite was replaced by the Fast Reaction Experiments
Enabling Science, Technology, Applications, and Research
(FREESTAR) payload, which was mounted behind the
SPACEHAB Research Double Module.
3
C
HAPTER
2
Columbias Final Flight
Figure 2.1-1. Columbia, at the launch pad on January 15, 2003. A C C I D E N T I N V E S T I G A T I O N B O A R D
COLUMBIA
A C C I D E N T I N V E S T I G A T I O N B O A R D
COLUMBIA
2 8
R e p o r t V o l u m e I A u g u s t 2 0 0 3
2 9
R e p o r t V o l u m e I A u g u s t 2 0 0 3
Schedule Slippage
STS-107 was finally scheduled for launch on January 11,
2001. After 13 delays over two years, due mainly to other
missions taking priority, Columbia was launched on January
16, 2003 (see Figure 2.1-1). Delays may take several forms.
When any delay is mentioned, most people think of a Space
Shuttle sitting on the launch pad waiting for launch. But most
delays actually occur long before the Shuttle is configured for
a mission. This was the case for STS-107 of the 13 delays,
only a few occurred after the Orbiter was configured for
flight; most happened earlier in the planning process. Three
specific events caused delays for STS-107:
Removal of Triana: This Earth-observing satellite was
replaced with the FREESTAR payload.
Orbiter Maintenance Down Period: Columbias depot-
level maintenance took six months longer than original-
ly planned, primarily to correct problems encountered
with Kapton wiring (see Chapter 4). This resulted in the
STS-109 Hubble Space Telescope service mission be-
ing launched before STS-107 because it was considered
more urgent.
Flowliner cracks: About one month before the planned
July 19, 2002 launch date for STS-107, concerns about
cracks in the Space Shuttle Main Engine propellant
system flowliners caused a four-month grounding of
the Orbiter fleet. (The flowliner, which is in the main
propellant feed lines, mitigates turbulence across the
flexible bellows to smooth the flow of propellant into
the main engine low-pressure turbopump. It also pro-
tects the bellows from flow-induced vibration.) First
discovered on Atlantis, the cracks were eventually
discovered on each Orbiter; they were fixed by weld-
ing and polishing. The grounding delayed the exchange
of the Expedition 5 International Space Station crew
with the Expedition 6 crew, which was scheduled for
STS-113. To maintain the International Space Sta-
tion assembly sequence while minimizing the delay
in returning the Expedition 5 crew, both STS-112 and
STS-113 were launched before STS-107.
The Crew
The STS-107 crew selection process followed standard pro-
cedures. The Space Shuttle Program provided the Astronaut
Office with mission requirements calling for a crew of seven.
There were no special requirements for a rendezvous, extra-
vehicular activity (spacewalking), or use of the remote ma-
nipulator arm. The Chief of the Astronaut Office announced
the crew in July 2000. To maximize the amount of science re-
search that could be performed, the crew formed two teams,
Red and Blue, to support around-the-clock operations.
Crew Training
The Columbia Accident Investigation Board thoroughly re-
viewed all pre-mission training (see Figure 2.1-2) for the
STS-107 crew, Houston Mission Controllers, and the Ken-
C
OLUMBIA
Columbia
was named after a Boston-based sloop com-
manded by Captain Robert Gray, who noted while sailing to
the Pacific Northwest a flow of muddy water fanning from
the shore, and decided to explore what he deemed the Great
River of the West. On May 11, 1792, Gray and his crew
maneuvered the Columbia past the treacherous sand bar and
named the river after his ship. After a week or so of trading
with the local tribes, Gray left without investigating where
the river led. Instead, Gray led the Columbia and its crew on
the first U.S. circumnavigation of the globe, carrying otter
skins to Canton, China, before returning to Boston in 1793.
In addition to Columbia (OV-102), which first flew in 1981,
Challenger
(OV-099) first flew in 1983, Discovery (OV-103)
in 1984, and Atlantis (OV-104) in 1985. Endeavour (OV-105),
which replaced Challenger, first flew in 1992. At the time
of the launch of STS-107, Columbia was unique since it
was the last remaining Orbiter to have an internal airlock
on the mid-deck. (All the Orbiters originally had internal
airlocks, but all excepting Columbia were modified to pro-
vide an external docking mechanism for flights to Mir and
the International Space Station.) Because the airlock was
not located in the payload bay, Columbia could carry longer
payloads such as the Chandra space telescope, which used
the full length of the payload bay. The internal airlock made
the mid-deck more cramped than those of other Orbiters, but
this was less of a problem when one of the laboratory mod-
ules was installed in the payload bay to provide additional
habitable volume.
Columbia
had been manufactured to an early structural
standard that resulted in the airframe being heavier than the
later Orbiters. Coupled with a more-forward center of grav-
ity because of the internal airlock, Columbia could not carry
as much payload weight into orbit as the other Orbiters. This
made Columbia less desirable for missions to the Interna-
tional Space Station, although planning was nevertheless
underway to modify Columbia for an International Space
Station flight sometime after STS-107.
Figure 2.1-2. Ilan Ramon (left), Laurel Clark, and Michael Ander-
son during a training exercise at the Johnson Space Center. A C C I D E N T I N V E S T I G A T I O N B O A R D
COLUMBIA
A C C I D E N T I N V E S T I G A T I O N B O A R D
COLUMBIA
Rick Husband, Commander. Husband, 45, was a Colonel in the
U.S. Air Force, a test pilot, and a veteran of STS-96. He received a
B.S. in Mechanical Engineering from Texas Tech University and a
M.S. in Mechanical Engineering from California State University,
Fresno. He was a member of the Red Team, working on experi-
ments including the European Research In Space and Terrestrial
Osteoporosis and the Shuttle Ozone Limb Sounding Experiment.
William C. McCool, Pilot. McCool, 41, was a Commander in the
U.S. Navy and a test pilot. He received a B.S. in Applied Science
from the U.S. Naval Academy, a M.S. in Computer Science from
the University of Maryland, and a