Written by Gerald Boerner

    

    
Commentary:

JerryPhoto_thumb2_thumb_thumb_thumb_Superstition holds that bad things happen in groups of three. If you believe that, the events of the last week fall into that pattern. on January 27th, the Apollo 1 fire took the lives of three of our astronauts. On the 28th, the Space Shuttle, Challenger, exploded just as it was about to go to full power on launch. And today, February 1st, we are covering the break up of the Space Shuttle, Columbia, the first shuttle to fly. So within a seven day period, we remember three disasters that have befallen our space program over the years.

night_space_shuttle_launch

Fortunately these disasters did not occur during one calendar week, but identifies a time of the year when they seemed to be more likely to occur. Why does this week seem to be so prone to accidents? After all, these missions were all associated with the Cape Canaveral/Kennedy Space Center complex located in southern Florida. That is not in the snow belt of the Great Lakes region nor were any of these accidents associated with hurricanes known to hit the area. So what could be the cause?

Well, for one thing, space exploration has inherent risks; it is far riskier than traveling on a scheduled airline. The fire in the Apollo 1 Command Module probably could have occurred anywhere. NASA was still experimenting with the environment, especially for the first three-man crew.

A second factor was the weather at the cape. While the area is generally known to have a warm, sunny climate. However, the nights often had low temperatures that resulted in overnight frost and the build-up of icicles. And both shuttle disasters were associated with the cold temperatures. We often still hear about a delay of a launch due to icing, a lesson learned from these disasters.

Columbia_sts-1_01

Finally, we must remain aware that these rockets ran on liquid hydrogen and oxygen. In that state, the fuel itself is at temperatures far below zero degrees Fahrenheit. That in itself can cause ice to form on the outside of the tanks, of which the shuttle launch vehicle has two. Between the ice formed on the launch platform itself and the ice on the tanks, the is a real possibility for some of this ice breaking off and damaging the insulation tiles, o-rings, and other connections.

We grieve with the families and friends of these brave astronauts who perished in this disaster. The two non-Americans had performed their assigned tasks as expected during their time in space. It was as shock to all watching, including myself, as this shuttle came in for its landing at the cape. We had seen so many of these re-entry into Earth’s atmosphere during previous flights and expected the same, routine glide of the shuttle to another safe landing. Then the disaster hit; the areas of the shuttle’s underbelly that lost its heat tiles caused the accident. We didn’t know what had happened until the announcement from mission control. While space travel has inherent risks, may we never see another scene like this!

But now let’s get started looking at the details of this Columbia Space Shuttle Disaster… GLB

These Introductory Comments are copyrighted:
Copyright©2012 • Gerald Boerner • All Rights Reserved

[ 2338 Words ]
    

    

Quotations Related to Shuttle:

[ http://www.brainyquote.com/quotes/keywords/shuttle.html ]

    

“After the Challenger accident, NASA put in a lot of time to improve the safety of the space shuttle to fix the things that had gone wrong.”
— Sally Ride

“I will go around the space shuttle and give a guided tour of the major areas and describe what is done in each area. This will be called The Ultimate Field Trip.”
— Christa McAuliffe

“I think the Space Shuttle is worth one billion dollars a launch. I think that it is worth two billion dollars for what it does. I think the Shuttle is worth it for the work it does.”
— Pete Conrad

“I had been here five years already, training very hard, learning about the systems, the shuttle, the station systems. But, everything really became real when I started to work with them.”
— Philippe Perrin

“After the loss of Columbia a couple of years ago, I think we were reminded of the risk. All of us, though, have always known that the Space Shuttle is a very risky vehicle, much more risky than even flying airplanes in combat.”
— Mark Kelly

    

NASA: The Columbia Space Shuttle Disaster…

    

    
KSC-107-Rollout_(Columbia)The Space Shuttle, or Space Transportation System (STS), is a reusable launch system and orbital spacecraft operated by the U.S. National Aeronautics and Space Administration (NASA) for human spaceflight missions. The system combines rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons. The first of four orbital test flights occurred in 1981 leading to operational flights beginning in 1982, all launched from the Kennedy Space Center, Florida. The system is scheduled to be retired from service in 2011 after 135 launches. Major missions have included launching numerous satellites and interplanetary probes, conducting space science experiments, and servicing and construction of space stations.

At launch, the Space Shuttle consists of the shuttle stack, which includes a dark orange-colored external tank (ET); two white, slender Solid Rocket Boosters (SRBs); and the Orbiter Vehicle (OV), which contains the crew and payload. Payloads can be launched into higher orbits with either of two different booster stages developed for the STS (single-stage Payload Assist Module or two-stage Inertial Upper Stage). The Space Shuttle is "stacked" in the Vehicle Assembly Building and the stack mounted on a mobile launch platform held down by four explosive bolts on each SRB which are detonated at launch.

Space Shuttle Columbia (NASA Orbiter Vehicle Designation: OV-102) was the first spaceworthy Space Shuttle in NASA’s orbital fleet. First launched on the STS-1 mission, the first of the Space Shuttle program, it completed 27 missions before being destroyed during re-entry on February 1, 2003 near the end of its 28th, STS-107. All seven crew members were killed. Following an independent investigation into the cause of the accident, NASA decided to retire the Shuttle orbiter fleet in 2010 in favor of the Constellation program and its manned Orion spacecraft. However, President Obama signed the NASA Authorization Act 2010 on October 11 which officially brought the Constellation program to an end.
    

    

The Disaster

    

The Space Shuttle Columbia disaster occurred on February 1, 2003, when the Space Shuttle Columbia disintegrated over Texas stretching from Trophy Club to Tyler and into parts of Louisiana during re-entry into the Earth’s atmosphere, resulting in the death of all seven crew members, shortly before it was scheduled to conclude its 28th mission, STS-107.

STS-107_reentrySTS-107 re-entry
      

The loss of Columbia was a result of damage sustained during launch when a piece of foam insulation the size of a small briefcase broke off the Space Shuttle external tank (the main propellant tank) under the aerodynamic forces of launch. The debris struck the leading edge of the left wing, damaging the Shuttle’s thermal protection system (TPS), which protects it from heat generated with the atmosphere during re-entry. While Columbia was still in orbit, some engineers suspected damage, but NASA managers limited the investigation, on the grounds that little could be done even if problems were found.

NASA’s original Shuttle design specifications stated that the external tank was not to shed foam or other debris; as such, strikes upon the Shuttle itself were safety issues that needed to be resolved before a launch was cleared. Launches were often given the go-ahead as engineers came to see the foam shedding and debris strikes as inevitable and unresolvable, with the rationale that they were either not a threat to safety, or an acceptable risk. The majority of Shuttle launches recorded such foam strikes and thermal tile scarring. During re-entry of STS-107, the damaged area allowed the hot gases to penetrate and destroy the internal wing structure, rapidly causing the in-flight breakup of the vehicle. An extensive ground search in parts of Texas, Louisiana and Arkansas recovered crew remains and many vehicle fragments.

Mission STS-107 was the 113th Space Shuttle launch. It was delayed 18 times over the two years from its original launch date of January 11, 2001, to its actual launch date of January 16, 2003. (It was preceded by STS-113.) A launch delay due to cracks in the shuttle’s propellant distribution system occurred one month before a July 19, 2002, launch date. The Columbia Accident Investigation Board (CAIB) determined that this delay had nothing to do with the catastrophic failure six months later.

The Columbia Accident Investigation Board’s recommendations addressed both technical and organizational issues. Space Shuttle flight operations were delayed for two years by the disaster, similar to the Challenger disaster. Construction of the International Space Station was put on hold, and for 29 months the station relied entirely on the Russian Federal Space Agency for resupply until Shuttle flights resumed with STS-114 and 41 months for crew rotation until STS-121.

    
The Crew:

Crew_of_STS-107,_official_photoThe crew of STS-107.
L to R: Brown, Husband, Clark, Chawla, Anderson, McCool, Ramon
      

  • Commander:
    Rick D. Husband, a U.S. Air Force colonel and mechanical engineer, who piloted a previous shuttle during the first docking with the International Space Station (STS-96).
        
  • Pilot:
    William C. McCool, a U.S. Navy commander
        
  • Payload Commander:
    Michael P. Anderson, a U.S. Air Force lieutenant colonel and physicist who was in charge of the science mission.
        
  • Payload Specialist:
    Ilan Ramon, a colonel in the Israeli Air Force and the first Israeli astronaut.
        
  • Mission Specialist:
    Kalpana Chawla, an Indian-born aerospace engineer was on her second space mission.
        
  • Mission Specialist:
    David M. Brown, a U.S. Navy captain trained as an aviator and flight surgeon. Brown worked on a number of scientific experiments.
        
  • Mission Specialist:
    Laurel Clark, a U.S. Navy captain and flight surgeon. Clark worked on a number of biological experiments.

    
Debris Strike During Launch

Approximately 82 seconds after launch from Kennedy Space Center’s LC-39-A, a suitcase-size piece of thermal insulation foam broke off the External Tank (ET), striking Columbia’s left wing Reinforced Carbon-Carbon (RCC) panels. As demonstrated by ground experiments conducted by the Columbia Accident Investigation Board, this likely created a 6-to-10-inch (15 to 25 cm) diameter hole, allowing hot gases to enter the wing when Columbia later reentered the atmosphere. At the time of the foam strike, the orbiter was at an altitude of about 66,000 feet (20 km; 13 mi), traveling at Mach 2.46 (1,870 miles per hour or 840 m/s).

The Left Bipod Foam Ramp is an approximately three-foot (one-meter) aerodynamic component made entirely of foam, as opposed to being a metal structure coated with foam. As such, the foam, not normally considered to be a structural material, is required to bear some aerodynamic loads. Because of these special requirements, the casting-in-place and curing of the ramps may be performed only by a senior technician. The shuttle’s main fuel tank is covered in foam as an insulator, to avoid ice forming on it when full of liquid hydrogen and oxygen, which itself could damage the shuttle when shed during lift-off. The bipod ramp (having left and right sides) was originally designed to reduce aerodynamic stresses around the bipod attachment points at the external tank, but it was proven unnecessary in the wake of the accident and was removed from the external tank design for tanks flown after STS-107 (another foam ramp along the liquid oxygen line was also later removed from the tank design to eliminate it as a foam debris source, after complex analysis and tests proved this change safe).

STS-107_launchColumbia lifting off on its final mission.
The light-colored triangle visible at the base of the
strut near the nose of the orbiter is the Left
Bipod Foam Ramp.
    

Bipod Ramp insulation had been observed falling off, in whole or in part, on many previous flights: STS-7 (1983), STS-32 (1990), STS-50 (1992), plus subsequent flights (STS-52 and -62) showing partial losses. In addition, Protuberance Air Load (PAL) ramp foam has also shed pieces, plus spot losses from large-area foams. At least one previous strike caused no serious damage. NASA management came to refer to this phenomenon as "foam shedding." As with the O-ring erosions that ultimately doomed the Challenger, NASA management became accustomed to these phenomena when no serious consequences resulted from these earlier episodes. This phenomenon was termed "normalization of deviance" by sociologist Diane Vaughan in her book on the Challenger launch decision process.

Video taken during lift-off of STS-107 was routinely reviewed two hours later and revealed nothing unusual. The following day, higher-resolution film that had been processed overnight revealed the foam debris striking the left wing, potentially damaging the thermal protection on the Space Shuttle. At the time, the exact location where the foam struck the wing could not be determined due to the low resolution of the tracking camera footage.

    

A statement from the Astronaut Families: (Houston Chronicle, 2-4-03, p. 1)

“On January 16th, we saw our loved ones launch into a brilliant, cloud-free sky. Their hearts were full of enthusiasm, pride in country, faith in their God and a willingness to accept risk in the pursuit of knowledge – knowledge that they might improve the quality of life for all mankind… Although we grieve deeply, as do the families of Apollo 1 and Challenger before us, the bold exploration of space must go on. Once the root cause of this tragedy is found and corrected, the legacy of Columbia must carry on for the benefit of our children and yours.”

    

    

Space Shuttle Columbia Disaster from NASA-TV… (9:27)

    

    

References

    

Background information is from Wikipedia articles on:

Wikipedia: Space Shuttle Columbia…
http://en.wikipedia.org/wiki/Space_Shuttle_Columbia

Wikipedia: Space Shuttle Columbia Disaster…
http://en.wikipedia.org/wiki/Space_Shuttle_Columbia_disaster

Wikipedia: NASA…
http://en.wikipedia.org/wiki/NASA

Wikipedia: Space Shuttle…
http://en.wikipedia.org/wiki/Space_Shuttle

Brainy Quote: SHUTTLE Quotes…
http://www.brainyquote.com/quotes/keywords/shuttle.html

    

Other Posts on Related Topics:

Prof. Boerner’s Explorations: NASA: The 2003 Columbia Space Shuttle Disaster…
http://www.boerner.net/jboerner/?p=16773

Prof. Boerner’s Explorations: NASA: The 1986 Challenger Space Shuttle Disaster
http://www.boerner.net/jboerner/?p=7597

Prof. Boerner’s Explorations: Apollo 1: Astronauts Die on Launch Pad in Capsule Fire
http://www.boerner.net/jboerner/?p=16654