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The 2003 Columbia Disaster
Columbia history
Milestones – OV102
July 26, 1972
Contract Award
Nov. 21, 1975
Start structural assembly of crew module
June 14, 1976
Start structural assembly of aft-fuselage
March 16, 1977
Wings arrive at Palmdale from Grumman
Sept. 30, 1977
Start of Final Assembly
Feb. 10, 1978
Completed final assembly
Feb. 14, 1978
Rollout from Palmdale
April 12 1981
Launch
Jan 16, 2003
28th and Last Flight
Columbia: 2003 mission STS-107
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The Columbia disaster occurred on February 1
It disintegrated over Texas during re-entry.
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Loss of all seven crew, before concluding its 28th mission.
Caused by damage sustained during launch when a piece of foam
insulation the size of a small briefcase (loaf of bread) and known as the
Left Bipod Foam Ramp broke off the main propellant tank.
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The damaged area allowed the hot gases to penetrate and
destroy the internal wing structure, causing the in-flight break-up.
Columbia
• Some “foam shedding” had been
noticed during the launch
• However, foam shedding was a
common occurrence and so it was
discounted.
• In the aftermath of the Challenger
disaster NASA had still not shaken
off elements of the mindset that
contributed the tragedy.
• They believed that as it worked,
there was nothing to fix.
• They were wrong.
Thermal Shield
• Primary heat shield made from
reinforced carbon/carbon tiles.
• Capable of withstanding 1700oC
• Secondary shield Fibrous
refractory composite insulation
(FRCI) tiles, which are flexible
and very tough.
• These combine with interior
insulation to protect the crew and
vehicle during the atmospheric
braking phase of orbital re entry.
External Tank Foam Insulation
Oxygen and hydrogen exist as gases at standard temperature and pressure.
Since their density in this state is quite low, the amount of these substances
required by the Space Shuttle would take up an enormous volume.
The only way to carry sufficient propellant in a reasonable amount of space is to
increase the density by cooling and pressurizing them until they become liquids.
External Tank Foam Insulation
The liquid oxygen is cryogenically cooled to -300°F (184°C)
The liquid hydrogen is chilled to -423°F (-253°C).
These liquids must be kept at high pressure and very low
temperature
or they will boil back to a gaseous state.
Foam Ramp
• The Left Bipod Foam Ramp was a one meter cast ramp made
entirely out of foam which weighed just under 1kg, dry.
• Its purpose was to improve the aerodynamic profile of the forward
orbiter bipod mount.
• This entire ramp, which was frozen by contact with the EFT broke
away 81.9 seconds after launch.
• The debris struck the leading edge of the left wing, punching a hole
through the carbon/carbon armour.
Warnings Ignored
• After Columbia safely reached orbit the
NASA engineering safety team made
three requests to the Department of
defence to provide high definition “spy”
satellite pictures of the orbiter.
• The requests were refused as the DOD
was busy over the middle east.
• The engineering team then proposed a
space walk to check the wing.
• NASA management refused on the
grounds that the crew schedule was full.
• Had the damage been discovered the
crew had no way of making repairs,.
• However, Columbia did not have enough
fuel to dock with the ISS.
• Despite rumours, Columbia was beyond
help of any kind.
Re Entry
• February 1st Columbia made a
perfect de-orbit burn and
began the aero braking part of
its re entry operation.
• 08:44:09 Columbia hit the
upper atmosphere at 7.8
km/s17,500mph.
• Leading edges quickly heat to
1400oC.
• 08:48:39 A sensor on the left
wing leading edge spar
showed strains higher than
those seen on any previous
Columbia re-entry.
• 8:49:32 Columbia executed a
pre-planned roll to the right.
• Speed: Mach 24.5.
Last Moments
• 8:53:46 Signs of debris being shed
were sighted by ground observers.
• Speed: Mach 22.8.
• Altitude: 230,200 feet.
• 8:54:24 The Maintenance,
Mechanical, and Crew Systems
Officer notes that four hydraulic
sensors in the left wing failed
simultaneously.
• Mission Control discuss the
instrument failure.
• Over the next few minutes ground
observers report seeing flashes of
light from Columbia, this was debris
falling from the orbiter and burning
up in the plasma stream.
Destruction
• 8:59:15 Engineering note
that pressure readings had
been lost on both left main
landing-gear tyres, they tell
the crew.
• A rapid cascade sensor
failure followed.
• The crew response is
garbled and before they can
repeat the message ground
observers report that
Columbia has disintegrated.
Survival
• Unlike the Challenger accident
there was never any possibility
of survival.
• The orbiter pitched left as its
wing broke up and lost
aerodynamic flow.
• Columbia turned sideways on
to the Mach 19.5 air stream.
• The orbiter was never
designed to withstand stress in
this orientation and broke up.
• A human dropped into an
airflow of this velocity would
disintegrate as quickly as the
orbiter.
Now
• Foam strikes at launch are still
a problem for the STS.
• Strikes occur because of the
nature of the lifter, and there is
no way to avoid the problem.
• NASA has investigated many
DIY repair methods, but none
have a realistic chance of
working.
• As of now, when a shuttle
launches there is another ready
on short standby.
The Next Step
• The future appears to lie with
truly reusable space vehicle.
• Research worldwide has been
leaning towards hybrid engine
space planes such as Skylon
and the X 34.
• These overcome most of the
disadvantages inherent in the
design of the shuttle.
• The technology is ready, all it
needs is the will and the
money.
Flight History
• The first shuttle, Columbia flew on
12 April 1981.
• Since then there have been 128
launches of which 2 ended
catastrophically.
• This gives the shuttle a failure rate
of 1.6%. Which makes it 300 times
more dangerous then crossing the
road.
• Columbia and Challenger were both
destroyed in accidents, they were
also the oldest of the five shuttles on
the NASA fleet.
Columbia: 2003 mission STS-107
The investigation board recommended:
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improving photography of launches, using telescopes to
photograph shuttles while they are in space
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adding the ability to repair a shuttle while in orbit.