Order Code RS21408
Updated October 13, 2005
CRS Report for Congress
Received through the CRS Web
NASA’s Space Shuttle Program: The
Columbia Tragedy, the Discovery Mission,
and the Future of the Shuttle
Marcia S. Smith
Resources, Science, and Industry Division
Summary
On August 9, 2005, the space shuttle Discovery successfully completed the first of
two “Return to Flight” (RTF) missions — STS-114. It was the first shuttle launch since
the February 1, 2003, Columbia tragedy. NASA announced on July 27, 2005, the day
after STS-114’s launch, that a second RTF mission has been indefinitely postponed
because of a problem that occurred during Discovery’s launch that is similar to what led
to the loss of Columbia. Two shuttle-related facilities in Mississippi and Louisiana were
damaged by Hurricane Katrina, which may further delay the next shuttle launch. It
currently is expected some time in 2006. This report discusses the Columbia tragedy,
the Discovery mission, and issues for Congress regarding the future of the shuttle. For
more information, see CRS Issue Brief IB93062, Space Launce Vehicles: Government
Activities, Commercial Competition, and Satellite Exports
, by Marcia Smith. This
report is updated regularly.
The Loss of the Space Shuttle Columbia
The space shuttle Columbia was launched on its STS-107 mission on January 16,
2003. After completing a 16-day scientific research mission, Columbia started its descent
to Earth on the morning of February 1, 2003. As it descended from orbit, approximately
16 minutes before its scheduled landing at Kennedy Space Center, FL, Columbia broke
apart over northeastern Texas. All seven astronauts aboard were killed: Commander Rick
Husband; Pilot William McCool; Mission Specialists Michael P. Anderson, David M.
Brown, Kalpana Chawla, and Laurel Clark; and payload specialist Ilan Ramon, an Israeli.
The last communication with Columbia was at about 09:00 EST. The shuttle was at an
altitude of 207,135 feet, traveling at a speed of Mach 18.3 (about 13,000 miles per hour).
The Space Shuttle Columbia and the STS-107 Mission
The Space Transportation System (STS) — the space shuttle — consists of an
airplane-like orbiter, two Solid Rocket Boosters (SRBs) on either side, and a large
cylindrical External Tank that holds the fuel for the orbiter’s main engines. The SRBs
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detach from the orbiter 2½ minutes after launch when their fuel is spent, fall into the
ocean, and are recovered for refurbishment and reuse. The External Tank is not reused,
but is jettisoned as the orbiter reaches Earth orbit, and disintegrates as it falls into the
Indian Ocean. At the beginning of 2003, all planned shuttle launches, other than STS-107
and two missions to the Hubble Space Telescope, were scheduled to support assembly and
operation of the International Space Station (see CRS Issue Brief IB93017, Space
Stations
, by Marcia Smith).
Columbia was one of four spaceflight-worthy reusable space shuttle orbiters in
NASA’s fleet. The remaining orbiters are Discovery, Atlantis, and Endeavour. A fifth
orbiter, Challenger, was lost in a 1986 accident. Another orbiter, Enterprise, was used for
approach and landing tests in the 1970s and was not designed to travel in space.
Enterprise now belongs to the Smithsonian’s National Air and Space Museum.
Columbia was the first spaceflight-worthy orbiter built for NASA by Rockwell
International (the space division of Rockwell, which built the orbiters, was later bought
by Boeing ). It was used for the very first shuttle flight on April 12, 1981. The STS-107
mission was Columbia’s 28th flight. Although Columbia was the oldest orbiter, Discovery
has been used for more flights (30). NASA has conducted a total of 113 shuttle launches
to date. Orbiters are periodically taken out of service for maintenance and overhaul.
Columbia last underwent such an “orbiter major modification” (OMM) period in 1999-
2001. STS-107 was Columbia’s second flight after the OMM. It was a scientific research
mission that, unlike most current shuttle launches, was not related to the International
Space Station (ISS) program (see CRS Issue Brief IB93017). The crew conducted a
research program involving 59 separate investigations. Some of the research required
analysis of specimens and data sets after the shuttle returned to Earth, and most were
destroyed along with the crew and orbiter. Other data, however, were transmitted to
ground-based researchers during the flight, and a few specimens were retrieved among
the debris, so some of the research survived. Quantifying the amount is difficult.
Previous Spaceflight-Related Crew Fatalities
The United States has suffered two other spaceflight-related accidents that caused
astronaut fatalities. On January 27, 1967, the crew of the first Apollo mission — Virgil
“Gus” Grissom, Edward White, and Roger Chaffee — died when electrical arcing in
spacecraft wiring caused a fire in their Apollo command module during a pre-launch test.
Apollo flights resumed after 21 months. On January 28, 1986, the space shuttle
Challenger (STS 51-L) exploded 73 seconds after launch, killing all seven astronauts
aboard: Francis “Dick” Scobee, Michael Smith, Judith Resnik, Ellison Onizuka, Ronald
McNair, Gregory Jarvis (a payload specialist from Hughes Aircraft), and schoolteacher
Christa McAuliffe. A commission chaired by former Secretary of State William Rogers
determined that cold weather at the launch site caused a rubber “O-ring” in one of the
SRBs to fail, allowing gases to escape, resulting in a catastrophic explosion. The shuttle
system was grounded for 32 months.
Four Soviet cosmonauts also died during spaceflights. Cosmonaut Vladimir
Komarov died during the first Soyuz flight on April 24, 1967. The spacecraft’s
parachutes did not function properly and it struck the ground with great force, killing
Colonel Komarov. Soviet human spaceflights were suspended for 18 months. Three
cosmonauts died on Soyuz 11 on June 29, 1971 when an improperly sealed valve allowed

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the spacecraft’s atmosphere to vent into space. The cosmonauts — Georgiy
Dobrovolskiy, Vladislav Volkov, and Viktor Patsayev — were not wearing spacesuits,
and were asphyxiated. There were no Soviet human spaceflights for 27 months.
The Columbia Accident Investigation Board (CAIB)
Then-NASA Administrator O’Keefe established the Columbia Accident
Investigation Board (CAIB) within hours of the tragedy, and transitioned responsibility
for the investigation to it on February 6, 2003. Chaired by Adm. (Ret.) Harold Gehman,
former NATO Supreme Allied Commander, Atlantic, CAIB had 12 other members (see
[http://www.caib.us]). All were appointed by Mr. O’Keefe, although some were added
to the initial roster upon the recommendation of Adm. Gehman. NASA revised the
Board’s charter three times to clarify its independence from NASA, primarily in response
to congressional concerns. However, the CAIB was created by NASA, included NASA
representatives, and the Board members were appointed by the NASA Administrator, so
concerns about its independence continued. CAIB released the results of its investigation
on August 26, 2003 in Vol. 1 of its report; Volumes II-VI were released in October 2003.
All are available at CAIB’s website. Board member Brig. Gen. Duane Deal wrote a 10-
page supplement, which is published in Vol. 2, providing additional recommendations
and viewpoints that he felt were important to convey.
The Causes of the Accident. The Board concluded that the tragedy was caused
by both technical and organizational failures. The technical cause was damage to
Columbia’s left wing by a 1.7 pound piece of insulating foam that separated from the
External Tank’s left “bipod ramp” and struck the orbiter’s left wing 81.9 seconds after
launch. The foam strike created a hole in a Reinforced Carbon-Carbon (RCC) panel on
the leading edge of the wing, allowing superheated air (perhaps exceeding 5,000oF) to
enter the wing during reentry. The extreme heat caused the wing to fail structurally,
creating aerodynamic forces that led to the disintegration of the orbiter. Organizationally,
the Board pointed to detrimental cultural traits and organizational practices that developed
over the institutional history of the program. Adm. Gehman cited a loss of “checks and
balances” in the program’s management that should have led to a recognition of the
danger posed by “foam shedding” from the External Tank, which had occurred on
previous shuttle missions. The Board also cited long term budget constraints, and
schedule pressure associated with assembly of the International Space Station, as factors.
CAIB’s Recommendations and the Stafford/Covey Task Group. The
CAIB made 29 recommendations, of which 23 are technical and six are organizational.
Of the 29 recommendations, the Board specified that 15 be completed before the shuttle
returned to flight status. CRS Report RS21606, NASA’s Space Shuttle Columbia:
Synopsis of the Report of the Columbia Accident Investigation Board
, by Marcia Smith,
provides a synopsis of all the recommendations.
NASA created a task group chaired by two former astronauts — Thomas Stafford
and Richard Covey — to evaluate NASA’s compliance with the 15 CAIB
recommendations that were to be completed before Return to Flight (RTF). The
Stafford/Covey Task Group ([http://returntoflight.org]) did not address organizational or
cultural issues, and was not tasked to determine whether the shuttle was ready to fly. The
Task Group held its final public meeting on June 27, 2005, concluding that NASA had
met the intent of 12 of the 15 CAIB RTF recommendations, but not the other three —

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preventing debris shedding from the External Tank, hardening the orbiter against damage
from debris, and developing inspection and repair techniques for the thermal protection
system. Some Task Group members indicated, however, that NASA had made
considerable improvements to shuttle safety, and considered the shuttle ready to fly.
Then-NASA Administrator O’Keefe said during 2003 and 2004 that not only would
NASA comply with the CAIB recommendations, but would “raise the bar” to ensure the
shuttle is as safe as possible. Dr. Michael Griffin became NASA Administrator in April
2005. At an April 18 press conference, he said he would listen carefully to advice, such
as that of the Stafford/Covey group, but that NASA and contractor personnel are those
responsible and accountable for determining if and when the shuttle is ready for RTF. He
would not commit to meeting every CAIB recommendation. In testimony to the House
Science Committee on June 28, 2005, he said that NASA had spent lot of money trying
to meet all the recommendations, but did not have the knowledge to do so in every case,
such as stopping all debris shedding from the External Tank.
The CAIB report also cited cultural issues (e.g., the safety culture) that could affect
shuttle safety. Those issues were addressed by an internal NASA study led by then-
NASA Goddard Space Flight Center Director Al Diaz. NASA also hired an outside
consulting firm, BST, to assess NASA culture and make recommendations about what
changes are needed. A February 5, 2005 BST report concluded that there is improvement,
but a significant number of people at NASA’s field centers do not yet perceive change.
Dr. Griffin terminated the contract with BST soon after becoming Administrator, saying
that NASA could deal with these issues internally.
Return to Flight (RTF): The STS-114 (Discovery) Mission
NASA launched the space shuttle on its first Return to Flight (RTF) mission, STS-
114, on July 26, 2005, using the Discovery orbiter. An earlier attempt on July 13 was
scrubbed due to a fuel sensor malfunction. The STS-114 crew was composed of six
NASA astronauts and one from the Japan Aerospace Exploration Agency (JAXA):
Commander Eileen Collins, Pilot James Kelly, and Mission Specialists Charles Camarda,
Wendy Lawrence, Soichi Noguchi (JAXA), Steve Robinson, and Andy Thomas. STS-
114 docked with the International Space Station (ISS) for most of its mission. STS-114
delivered supplies, repaired ISS components, and tested inspection and repair techniques
for the orbiter. The STS-114 mission was extended by one day so the shuttle crew could
assist the ISS crew members in stowing supplies. Inclement weather at Kennedy Space
Center, FL delayed the shuttle’s landing until August 9, and diverted it to Edwards Air
Force Base, CA.
On June 27, NASA announced that further shuttle launches would be indefinitely
postponed after discovering that a comparatively large piece of foam broke off from
Discovery’s External Tank during launch, similar to what happened to Columbia. In this
case, NASA determined that it did not hit the orbiter. Subsequently, several smaller pieces
were found to have broken off and may have hit the orbiter’s wing. Cameras and other
sensors aboard Discovery and the ISS took detailed images to determine if there was any
damage and none was discovered. However, the images revealed that two “gapfillers”
— ceramic-coated fabric that fills gaps between the thermal protection tiles — on the
bottom of the orbiter were protruding, which could affect aerodynamic heating during
reentry. Astronaut Robinson removed them during a spacewalk.

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The second RTF mission was scheduled for September 2005 with the mission of
continuing testing post-Columbia fixes and resupplying the ISS. NASA continues to
study why the foam loss on STS-114 occurred. That work is being slowed by hurricane
damage to the Michoud Assembly Facility, in New Orleans, LA, where the External
Tanks are manufactured. It is operated for NASA by Lockheed Martin. The next shuttle
launch currently is expected no earlier than May 2006.
Issues for Congress
Cost. In July 2004, NASA released a cost estimate for RTF covering the years
FY2003-2009: $2.2 billion, double the previous estimate of $1.1 billion. For FY2005,
NASA requested $4.3 billion for the shuttle program. In November 2004, NASA
informed Congress it needed $762 million more than expected for FY2005. In the
FY2005 Consolidated Appropriations Act (P.L. 108-447), Congress approved the $4.3
billion requested, subject to an across-the-board 0.80% rescission, and said that NASA
could submit a request for supplemental appropriations, or reprogram funds from other
NASA programs. According to a May 10, 2005 update to its FY2005 operating plan,
NASA reprogrammed the following funds into RTF: $55 million from the Science
Mission Directorate ($20 million from space science, $35 million from earth science);
$375.8 million from the Exploration Systems Mission Directorate ($73 million from
biological and physical research, $204 million from human and robotic technology, and
$98 million from transportation systems); and $331.2 million from the Space Operations
Mission Directorate ($160 million from the space station, $170 million from space shuttle
upgrades, and $1.2 million from space flight support). Separately, Congress appropriated
$126 million to NASA in an FY2005 emergency supplemental (P.L. 108-324) for
damages at Kennedy Space Center, FL, from the 2004 Florida hurricanes. NASA officials
say those funds are not available for RTF.
The CAIB noted that long term budget constraints were a factor in the Columbia
tragedy. NASA’s FY2006 shuttle budget request is $4.5 billion, with a projection that it
will decline to $2.4 billion by FY2010 as NASA phases out the shuttle (see below). What
additional funds may be needed to fix the foam-shedding problem is unclear at this time,
as is the shuttle’s future overall, but adequate funding is likely to remain an issue.
The Shuttle’s Future. The foam-shedding event during Discovery’s launch and
the resulting decision to suspend further shuttle launches adds to the complexity of
decisions about the shuttle’s future. Prior to Discovery’s launch, discussion was focused
on President Bush’s January 2004 directive that the shuttle be retired in 2010. That
decision was made in the context of the President’s announcement of a new “Vision for
Space Exploration,” wherein NASA is to focus its attention on returning astronauts to the
Moon by 2020 and someday sending them to Mars (see CRS Report RS21720, Space
Exploration: Issues Concerning the “Vision for Space Exploration
, by Marcia Smith).
Under the plan, the shuttle — in its current form — would be terminated in 2010,
primarily so that its funding can be redirected towards achieving other aspects of the
Vision. The 2010 date also coincides with the CAIB’s recommendation that if the shuttle
is to be flown longer, it should be recertified. In the wake of the problems during
Discovery’s launch, some may argue that the shuttle be discontinued sooner. Two key
issues raised by the decision to end shuttle flights by 2010 are the extent to which the
United States wants its own ability to launch astronauts into space, and the importance of
completing ISS construction and meeting U.S. commitments to other ISS partners.

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The shuttle is the only U.S. vehicle capable of taking astronauts to space today. As
part of the Vision, NASA is building a new “Crew Exploration Vehicle” (CEV). The
original schedule called for it to be available for launching crews to Earth orbit by 2014,
meaning there would be a multi-year gap between the end of the shuttle program and the
availability of CEV. During that time, NASA would be dependent on Russia for human
access to space. Russia is currently providing crew transportation services to NASA at
no cost under a 1996 agreement; that agreement will be fulfilled in April 2006. Russia
insists that it expects to be paid for any future arrangements, but NASA is not permitted
to pay Russia for such services unless Russia abides by the Iran Nonproliferation Act
(INA). See CRS Report RS22072 and CRS Report RS22270 for a discussion of the ISS-
INA linkage, and congressional deliberations on whether to amend the INA. Dr. Griffin
wants to accelerate the availability of the CEV to reduce the gap as much as possible, not
only because of INA concerns, but also because he believes the United States should not
be dependent on any other nation for human access to space. Senators Hutchison and Bill
Nelson offered an amendment to the FY2006 Department of Defense authorization bill
(S. 1042) on July 21, 2005 expressing the sense of Congress about the importance of
uninterrupted U.S. preeminence in human space flight, noting that China and Russia can
launch astronauts (Congressional Record, pp. S8638-S86340). Debate on the bill was
suspended while the amendment was pending, and has not resumed.
The shuttle’s primary purpose today is assembly and servicing of the ISS. Dr.
Griffin also promised to reassess whether or not to use the shuttle for one more servicing
mission to the Hubble Space Telescope (see CRS Report RS21767). The need to
complete ISS assembly and meet U.S. commitments to its ISS partners, and to service
Hubble, will need to be weighed against the costs of fixing the foam-shedding problem
and the risks of shuttle launches. ISS construction is about 50% completed, and some of
the segments waiting to be launched are those built by the other partners. President Bush
said the United States would meet its commitments to the ISS partners. NASA’s current
target is to launch the shuttle 18 times to support the ISS, with one potential additional
launch to Hubble, by the end of 2010. Whether it can achieve that many launches remains
to be seen. Another question is whether setting a firm deadline for ending shuttle flights
places undue schedule pressure on shuttle program managers to complete as many
launches as possible within whatever remaining time there is. CAIB cited schedule
pressure as a factor in the Columbia accident.
The effect on ISS utilization by NASA and its partners is another issue. ISS was
designed to be serviced by the shuttle, which can carry larger crews than the Russian
Soyuz spacecraft, and larger and heavier cargo than the Russian Progress cargo spacecraft.
In addition, the shuttle is the only cargo spacecraft that can return large amounts of
material to Earth (Russia’s Progress burns up as it reenters the atmosphere). Without the
shuttle, the results of scientific experiments, equipment needing repair, and other items
could only be returned if they fit within the small confines of the Soyuz capsule along
with whatever crew members were returning to Earth (unless new cargo spacecraft are
developed). How NASA can ensure that the shuttle system will remain safe as workers
and vendors move on to other projects as the shuttle program comes to an end is also
being discussed. NASA plans to develop two “shuttle-derived” launch vehicles (see CRS
Issue Brief IB93062), which could mitigate some of the shuttle workforce displacements.