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Columbia's Final Minutes in Detail

grub writes "This article on Newsday has an excerpt from 'Comm Check... The Final Flight of Shuttle Columbia,' by Michael Cabbage and William Harwood describing the last minutes of Columbia's final flight in detail."

19 of 494 comments (clear)

  1. Hot Gas != Plasma by RobertB-DC · · Score: 5, Informative
    From the article: ...and that a plume of super-heated plasma entering through that breach had destroyed the wing and triggered the destruction of the orbiter.

    While original reports used the term "plasma", there's a good explanation at space.com's Columbia FAQ that explains that the hot gas that entered the shuttle's wing was *not* "plasma", as defined by science:
    PLASMA: What is it?

    [IMPORTANT NOTE: Officials now say that the hot gas that surrounded Columbia and appeared to breach the craft had probably not yet reached the plasma state.]

    Plasma is sometimes called a fourth state of matter (in addition to solid, liquid, gas). It's created when gas is superheated and electrons are stripped out, leaving electrically charged particles.
    Not to be a science nazi, but there's an important distinction between sci-fi-sounding "plasma" and the mundane -- but still deadly -- "very hot gas".
    --
    Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
    1. Re:Hot Gas != Plasma by RobertB-DC · · Score: 4, Informative

      [Plasma may be] but rather a transference state between gas and Bose-Einstienian condensate

      We're trending off-topic, but I'm curious. As I understand (imperfectly), a gas becomes a plasma by becoming completely ionized at high temperature. But a Bose-Einstein condensate requires a temperature very close to absolute zero, so that the particles' velocity approaches zero and the atoms superimpose (Wiki make um smarter! Ugh!). How would plasma fit into that phase transition?

      --
      Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
    2. Re:Hot Gas != Plasma by chl · · Score: 3, Informative
      the plasma I learned about in college 20 or so years ago.

      Your memory fails you. IAAPP, and in physics at least, 'plasma' always refers to partially or totally ionised gasses.

      chl

  2. Re:May their souls rest in peace. by sahonen · · Score: 5, Informative

    There's a memorial at Cape Canaveral with the names of ALL of the people who have died in our pursuit of outer space.

    --
    Make me a friend and I'll mod you up
  3. Atlantic Monthly by Sean80 · · Score: 5, Informative

    Above and beyond this article, if you can get your hands on the article on the Colombia tragedy which was published in Atlantic Monthly, do it. As always for Atlantic Monthly, easily the most intelligent commentary I've seen about the event, and a couple of closing sentences that will stay with me forever.

    1. Re:Atlantic Monthly by jhsiao · · Score: 5, Informative

      The Atlantic Monthly article was in the November 2003 issue. It's available online here.

  4. Definitely RTFA... by bc90021 · · Score: 4, Informative

    ...it's an incredible piece, and very well written. One never understands such things until it is succinctly written out, and these authors did an amazing job.

  5. I'm a budgeteer ... by plawsy · · Score: 3, Informative

    ... not a rocketeer. - Sean O'Keefe, NASA Adminstrator

  6. Re:bad management kills by phr1 · · Score: 4, Informative
    So every fatal car accident caused by untimely mechanical failure is "murder by manufacturer"?

    It's murder by management if the engineers tell management "hey, this part isn't strong enough, we have to use a stronger part or some cars are going to blow up" and management says "nah, that'll cost too much, forget it". Ford Motor Company was in fact indicted for second-degree murder over the notorious exploding Pinto gas tank, after it came out that basically the above engineer-management exchange had taken place.

    Similar exchanges took place before the Challenger explosion (engineers didn't want to launch until the O-ring erosion had been fixed, and management overruled them) and the Columbia crash (engineers wanted photos of the insulation damage so if necessary they could make a contingency plan, and management spiked the request). So those also fit the pattern of murder by management.

  7. Re:bad management kills by ChuckDivine · · Score: 4, Informative

    Do check out the Columbia Accident Investigation Board report at http://www.caib.us/. Or, after February 1st, go to the main NASA site and look for the links to the CAIB report.

    Management and political leadership did kill.

    --
    "Beer is proof God loves us and wants us to be happy." -- B. Franklin
  8. Re:Nasa won't learn by bjhonermann · · Score: 3, Informative

    Unfortuantely, there was no way for Columbia to get tot the ISS even if they had known about the problem. The Columbia was the heaviest shuttle in the fleet and was incapable of getting to the orbit that ISS is at even if a mission called for it.

    Also, when a shuttle mission is sent to the ISS they have to carry special equipment in the cargo area to actually connect the shuttle to ISS and transfer crew members. The Columbia obviously didn't have that kind of equipment along.

    From what I understand, about the only thing they could have done had they known was a) try and launch another shuttle to evacuate the crew, or b) bring them down in Columbia and hope that the shuttle would hold together long enough for the crew to be able to use an escape hatch and parachute to the ground. The likelihood of getting another shuttle prepped in time was almost nill so it's quite possible that even if they did know they didn't really have an alternative anyway.

    -Brian

  9. Definition of plasma... by Dr.+Zowie · · Score: 5, Informative
    A gas doesn't have to be fully ionized to be plasma. The transition comes gradually as more and more of the gas is ionized. The crucial parameter is the ratio of the average spacing of the molecules, and something called the "Debye radius", that measures the distance over which charge neutrality holds (that is to say, plasmas are charge-neutral mixes of positively and negatively charged particles; so if you add, say, some extra positive charges to a small region you will attract a cloud of negative charges to cancel it out. The Debye radius tells you the size of the cloud).

    To be a plasma, the gas should have many free electrons (or ions) in each Debye length. There could be many more neutrals, just along for the ride, in the same space.

    Most molecular gases become more or less fully ionized at around 10,000 degrees Kelvin (give or take a factor of four or so, depending on composition) since that's the temperature at which the collision energy becomes significant compared to valence electron binding energies, so most collisions can make new ions. So anything hotter than that is definitely plasma.

    But even a fraction of a percent ionization is often enough to give you the nice bulk behavior of a plasma, because the ionized particles do their thing and drag along the neutral ones by collision. Depending on the density, it's probably reasonable to call the 8,000F (3800K) gases "plasma".

  10. Not "Insightful" by Unknown+Kadath · · Score: 4, Informative

    Parent poster is operating under a series of faulty assumptions and applying some bad reasoning.

    When you've got an object traveling very vast what happens? What happens when you move your feet across the carpet? Static electricity. What is static? Electrons stripped from one object to another.

    Static charge accumulates when loosely-held valance electrons transfer from less to more electonegative atoms. (Electronegativity is a measure of an atom's tendency to attract electrons.) It is analagous but not identical to dissociation, which occurs in plasma formation. Dissociation is the complete stripping of electrons from the nucleus, even the tightly-held inner shell electrons, which do not transfer when you shock someone by scuffing your feet on the rug. Dissociation, especially of diatomic gases such as O2 and N2, the major components of the atmosphere, requires immense amounts of energy. N2, for example, dissociates around 9000K (~16,000 deg F). For comparison, graphite vaporizes at about 6000K (~10,000 deg F).

    Static can be a huge problem in pipes that move large amounts of non-polar fluids. Guess what most gasses in the upper atmosphere are? Non-polar fluids. So, there is your ionized high velocity, high temperature gas. Plasma.

    I don't know alot about the shuttle's design, but I'd guess that if you talked with some NASA aerospace engineers they'd confirm this phenomenon. It's got to be a factor with all very fast aircraft.

    Static charge is not plasma. Plasma requires complete ionization, and static doesn't even come close.

    Static is not a problem insofar as flight mechanics are concerned. It may be a factor for avionics, as much as it is for any electrical system, but that is outside my area of experience.

    -Carolyn

    --
    Like Daddy always said: if you can't dazzle 'em with brilliance, baffle 'em with bullshit.
  11. some details... by Tired_Blood · · Score: 4, Informative

    1. Of the two, only Marie Curie died from causes of radiation exposure. Pierre got run over by a vehicle, but would have probably met the same fate.
    2. Clarence Dally was Thomas Edison's assistance with Xrays. Here's a link.

    --
    This is not my sig.
  12. Re:one thing i don't understand by _bug_ · · Score: 3, Informative

    How can a hole being ripped in the wing, or any other part of the shuttle not be picked up by some sensor?

    The leading edge of the shuttle's wing is flat. Over that goes a series of reinforced carbon-carbon (RCC) panels which form a smooth, aerodynamically-friendly shape. These RCC panels are shaped something like a V rotated 90 degrees. This creates a small cavity between the RCC panels and the leading edge spar of the wing, which is where the RCC panels are bolted on.

    The bolts that hold the RCC panels to the spar are covered in insulation designed to take up to 3,200 degrees F.

    The initial impact created a hole in the underside portion of the RCC panels, but did not go through the leading-edge of the wing itself.

    So to detect this you would need to either have sensors on or inside the cavity of the RCC panels OR you detect it by the hole's effects on the wing, such as an increase in left-side drag.

    From what bits I've read of the CAIB's final report, I don't believe there are any sensors on the inside of the RCC panels or inside the cavity between the RCC panels and the leading edge of the wing. Reason being it can get pretty hot in there and would probably destroy any sensors that were placed inside. So no direct sensor readings are going to detect the hole, becaue there aren't any.

    So now to detect it right away you need to be able to observe the hole's effects in the form of drag. Problem is, this hole was on the underside of the wing. During ascent the shuttle is pointed vertically up so the effects of this 8 inch hole would be minimal at best and went undetected. Once in orbit, drag, for the purposes of this discussion, doesn't exist.

    So there really wasn't any way to detect the hole or its effects.

    The only way, until re-entry, would be a visual inspection of the area.

    The shuttle wasn't carrying any equipment for a space walk, so that wasn't possible. The shuttle's orientation during orbit is to have it's belly facing away from the Earth, so land-based telescopes and cameras would have been useless.

    Spy satellites or some other device in a higher orbit with a camera on board might have been able to do this. But I don't believe a request for such a thing was ever put to the CIA or NSA. It was certainly suggested, but I think the request was never pushed forward.

    So that's why it was never detected until it was too late.

    The only area I'm not 100% certain on is the sensors inside the RCC cavity. I know during tests of the RCC, they had sensors all over the thing. I've seen pictures of the inside leading edge which had some sensors, but I never saw anything inside the RCC cavity itself.

    Given the need for insulation of bolts used to hold the RCC panels to the spar, I think my supposition that it's simply too hot inside that cavity for those sensors may be correct.

    Anyone care to correct me on this?

  13. Re:one thing i don't understand by jeremyp · · Score: 4, Informative

    Read the actual report of the investigating team. It's written in a very accessible style and comes to the conclusion that a rescue mission would have been possible if the problem had been discovered before reentry.

    --
    All I want is a secure system where it's easy to do anything I want. Is that too much to ask ~~ Randall Munroe
  14. Re:May their souls rest in peace. by g1zmo · · Score: 3, Informative

    One of the astronauts, Dr. Kalpana Chawla, was an alum of my school. Chawla Hall is a $20 million dorm on campus that is nearing completion. I remember a story in the school newspaper that her husband was not happy with the dedication service when construction began. Everyone tried to make it out to be a deep, spiritual event and that is not how she would have wanted it. She was not a religious person at all, and her husband felt that the religious subversion was completely inappropriate. He even said she would have walked away from the service had she been there.

    --
    I have found there are just two ways to go.
    It all comes down to livin' fast or dyin' slow.
    -REK, Jr.
  15. Did you read the CAIB report? by Slashamatic · · Score: 4, Informative
    There were two options had the problem been identified early enough. The first was to rest, use minimal supplies and rush through the preparation of Atlantis on the ground. Transits could have been made using a tether. No direct connection would be needed. The second option was to improvise a patch. The first option was probably a goer, especially if NASA staff were aware of a marooned mission. The second option was a possibility, and certainly offerred a greater chance of survivability than no action at all.

    Essentially this is a myth circulated by some NASA management apologists.

  16. Re:Nasa won't learn by Picass0 · · Score: 4, Informative

    ...could they have hung out at the ISS and waited for NASA to send up a rescue craft?

    No. Columbia was the oldest orbiter, and even though it had been refit and upgraded in many ways, it still had it's original airframe. Columbia was the heaviest of the orbiters, and unable to achieve the high orbit of the ISS. It was the only shuttle unable to make flights to the space station.

    Even IF Columbia were able to achieve the altitude needed for docking, it was in an orbit that would take it nowhere near ISS. And IF it had been able to make it to ISS, Columbia did not have the docking module needed to dock to ISS. Without the docking module, the crew would need to EVA to get to ISS. Columbia did not have the spacesuits needed for this.

    Columbia's ONLY option would be to wait for Atlantis, and Atlantis would have to be preped for launch in such a hurry that it's crew would be at extreme risk.

    Columbia should have been retired a long time ago. We should have been using a 2nd gen shuttle by now. It may be sad to think that the shuttle fleet is to be retired with NASA's Mars goals, but in truth it was time.

    I'm a big fan of the Space program, but NASA's claims that the shuttle fleet was designed to fly for 50 years should fail anybody's smell test. We don't use school buses for 50 years. Are we supposed to believe that they accounted for 50 years of metal fatigue when designing the shuttle fleet?

    After Challenger NASA placed the odds for loss of a shuttle at 1 in 100. Those are risky odds. You wouldn't fly on an airplane with those odds.

    The Shuttles never made the price of lauching satelites cheaper (it's primary goal) and it never made the turnaround cycle shorter than disposable launch systems.

    It's time for NASA to get out of the trucking business and back to science.