Follow Slashdot stories on Twitter

 


Forgot your password?
Close
typodupeerror
×
NASA Space

NASA Probes Shuttle Oxygen Leak 150

Posted by ScuttleMonkey from the getting-started-with-a-bang-not-necessarily-a-good-thing dept.
Cherita Chen writes "NASA is investigating the possibility of a gaseous oxygen leak, posing a serious fire risk, during the launch of the space shuttle Discovery in July. From the article: 'Engineers uncovered possible evidence of high concentrations of the gas in the rear engine compartment about two minutes after lift-off. A leak could lead to a fire or even an explosion in flight.'"
This discussion has been archived. No new comments can be posted.

NASA Probes Shuttle Oxygen Leak More

NASA Probes Shuttle Oxygen Leak

Comments Filter:

  • Oh no! (Score:5, Funny)

    by mrRay720 ( 874710 ) on Tuesday December 13, 2005 @08:08PM (#14252081)
    They'd better not let all of that dangerous oxygen escape into the atmosphere!!

    • Re:Oh no! (Score:5, Funny)

      by JourneyExpertApe ( 906162 ) on Tuesday December 13, 2005 @08:18PM (#14252139)
      Oxygen isn't dangerous per se, but it becomes deadly when it reacts with hydrogen to form dihydrogen monoxide.

      • It's True! (Score:5, Informative)

        by andyb2083 ( 734615 ) on Tuesday December 13, 2005 @08:21PM (#14252158)
        See DHMO.org [dhmo.org] for more info.
      • Oxygen is poisonous in high concentrations, hydrogen can asphyxiate you, and "dihydrogen monoxide" can cause both water intoxication and drowning.

        Oh, and haven't you ever seen a shuttle launch? It isn't the dihydrogen monoxide that will kill you, but the reaction that creates it...
      • Well, as long as it's only in the rear engine compartment... Imagine what could happen if all that oxygen got at the crew!
      • Yes, this element O2 or 'Oxygen' is a hazard to the environment! I can't believe they just let that stuff leak out - just another example of our tax dollars wasted at Nasa. Free O2 (or Oxygen in laymens terms) is corrosive and does millions of dollars of damage each year all over this country! This is especially true when it comes into contact with any bare metal of your car in the front yard on blocks. We need to have this stuff regulated or banned or both - not to mention that dihydrogen monoxide ment
      • Oxygen isn't dangerous per se, but it becomes deadly when it reacts with hydrogen to form dihydrogen monoxide.

        This statement is actually correct (though not in the way it was intended): the enthalpy of formation of water is frickin' big. If you have large amounts of hydrogen burning, you don't want to be near it.

      • Atmospheric oxygen is actually very balanced (Score:5, Informative)

        by EmbeddedJanitor ( 597831 ) on Tuesday December 13, 2005 @09:30PM (#14252583)
        In a very interesting book called "Oxygen: The molecule that made the world", Nick Lane explains a lot of things, including why our atmospheric oxygen level is what it is. Even a small increase (a few %) can increase the likelihood of combustion of plant materials and other natural oxygen absorbing reactions. If oxygen gets too low, then carbon depositing reactions, amongst others, increase to release more.

        If you mess with oxygen levels the chances of fire go up quite a bit, one of the reasons why people are paranoid about static electricity some high oxygen environments like operating theatres and decompression chambers.

      • actually yes it does. If enough of it does fast enough you bet a HUGE earth shattering kaboom.
      • the danger isn't the product of the reaction the danger is the heat the reaction creates!

        but then you probablly new that and were just propogating the DHMO hoax.
    • Especially if it's the gaseous sort. I heard it's both flammable and inflammable - imagine what could happen if it mixed with itself!
    • Oxygen IS really dangerous. It's the fuel for every combustion reaction (hence why it is in the fuel to begin with), and can explode. And if it's leaking, the explosion may no longer be directed in the way you want it, and suddenly BOOM! no more shuttle, no more crew, etc.

  • some comments (Score:1, Interesting)

    by ls -la ( 937805 )
    NASA is investigating the possibility of a gaseous oxygen leak,

    If it's leaking into the atmosphere it's going to become gaseous very quickly anyway.

    posing a serious fire risk... evidence of high concentrations of the gas

    High concentrations of oxygen won't combust, it's the lower-middle concentrations (especially mixed with certain other chemicals) you have to watch for.

    Well, at least NASA's engineers are finding the space shuttle's flaws, even if they're not FIXING them.

    • some comments on your comments (Score:5, Informative)

      by JourneyExpertApe ( 906162 ) on Tuesday December 13, 2005 @08:27PM (#14252199)
      High concentrations of oxygen won't combust, it's the lower-middle concentrations (especially mixed with certain other chemicals) you have to watch for.

      I believe you're confusing oxygen with a fuel. Oxygen won't combust at all. But putting a solid or liquid fuel in contact with pure oxygen and an ignition source is a recipe for disaster. It's true that if the oxygen concentration were to reach such a high level that all other flammable gasses present were below their LFL the mixture wouldn't burn, but that wouldn't make the situation safe because a more concentrated fuel source could be introduced and you'd have a huge fireball on your hands.
      • I raise you a canister of LOX and a lit match :P

        Famous last words: "They couldn't hit an elephant at this dist--"

      • Re:some comments on your comments (Score:2, Informative)

        by Anonymous Coward
        Actually oxygen and nitrogen *do* combust at about 5200 celsius.
    • High concentrations of oxygen can cause non-gaseous things inside of the environment to burst into flame if they're at all flammable.

      Also, on the way to getting to a high concentration, one usually experiences a state of a medium concentration.

      • Just to nitpick, things don't burst into flame without ignition sources. Even in 100% oxygen under 2200psi of pressure. You don't see many oxygen tanks exploding on their own, do you?

        The tiniest spark near anything remotely flammable would cause such a system to explode violently though.
        • Yes, that's true. You do need a flame, a spark... or to otherwise get sufficient heat added to the system. You know, like lighting something on fire with a magnifying glass? Of course, an O2 tank would probably explode from overpressure before igniting, if you were to try to heat it to the point where it combusted. It might be a fun experiment, though, from a sufficient distance.
        • Well, under 100% oxygen it would be really hard to combust anything... because there's nothing to combust!
        • Just to nitpick, things don't burst into flame without ignition sources.

          Tell that to Rudolph Diesel. As anyone refilling oxygen cylinders will confirm, even tiny traces of grease on the threads of the cylinder can ignite and explode when the cylinders are pressurised.

  • Gas in the rear engine compartment... (Score:5, Funny)

    by Anonymous Coward on Tuesday December 13, 2005 @08:17PM (#14252133)
    ...can really make you unpopular with the rest of the crew.

  • 500 parts per million? (Score:5, Interesting)

    by Lord Byron II ( 671689 ) on Tuesday December 13, 2005 @08:17PM (#14252134)
    What is the significance of the 500 parts per million figure in the article? What is the rest of the gas made up of? As a reminder, normal air is 20% oxygen, or 200,000 parts per million.
    • Your right 20% at sea level....but 2 minutes into flight they aren't anywhere near sea level.
      • But if 200,000ppm is not harmful at sea-level, then why is 500ppm harmful at altitude?
        • Because the concentration of the oxygen is significantly greater 2 minutes into flight at high altitudes relative to the concentration of oxygen in the atmosphere.
        • Taking a stab in the dark:

          Maybe because 500ppm at the sensor means 100% O2 near the area of the leak. Makes sense after all. If something started burning somewhere between the 100% part and the 500ppm part, it could spread very quickly in the direction of the leak. Once the tank gets hot, the leak would speed up which would feed the fire even more. You see where this is going end up.
        • oxygen + burnable substance + ignition source = 7 dead astronauts, debris everywhere, tedious public handwringing from our "public servants" and Chinese/Russian/European owndership of space.

          Not so good.
    • What is the significance of the 500 parts per million figure in the article? Something's leaking.
    • What is the significance of the 500 parts per million figure in the article? What is the rest of the gas made up of? As a reminder, normal air is 20% oxygen, or 200,000 parts per million.

      No more significance than rumors of (insert male celeb)-iffer's breakup, or Jane Whosis on As the World Turns getting a positive on her latest test results, meaning she has to go back into the hospital and lie in bed for a couple episodes.

      Seriously, someone strips a screw on some control panel, and it warrants a press

    • Re:500 parts per million? (Score:5, Interesting)

      by RayBender ( 525745 ) on Tuesday December 13, 2005 @09:21PM (#14252532) Homepage
      The engine compartments are filled with pure N2 to prevent the possibility of fires. 500 ppm of O2 is quite small, but it shouldn't be there at all - clearly something is not right...

      By the way, the inert-gas fill of the engine spaces has caused problems - I think a couple ground crew were killed some years back when they entered the spaces before they had been properly vented.

      • Firstly, you never prevent the possibility, you only reduce the probability.
        Second, you can only ever replace a risk with another risk. The question is whether the risk of suffocation is less than the risk of fire?
        BTW - I am a qualified risk manager.

    • That's a good question. The inside of the rear cabin is vented shortly after lift-off, so it's not as if they expected to find none, they just found more than they expected. This indicates a leak or an instrumentation issue (one of the leak detection bottles failed to function at all), but keep in mind the SSME's have a pretty decent history of leaking from all sorts of places to the point of early engine shutdown (STS-93).

      It sounds to me like NASA is trying to kill off the shuttle... even the most esoteric
    • Isn't ppm a percentage, shouldn't 200ppm at sea level be the same percentage of oxygen as 200ppm at altitude (just fewer molecules). Or is this not how the sensors are calibrated.
    • The compartment is normally full of pure nitrogen ("inerted") prior to launch; any oxygen there is due to a leak somewhere.
  • It appears that they are more concerned with the amount of oxygen present than the location of the oxygen. Does this mean that they expect a leak in there in the first place?

  • Scuttle the Shuttle (Score:4, Insightful)

    by Anonymous Coward on Tuesday December 13, 2005 @08:31PM (#14252230)
    The shuttle program has run its course, it's too complicated to maintain and operate, unreliable and countless times, astronauts, engineers have said it that it would have been more cost effective and safer to just use re-usable expendable rockets. The irony is Nasa probably had hints about this back in the 80's and only now 20+ year's later are the heading to the drawing board to come up with a replacemnet. NASA lost it's forward thinking ability after the moon landings... We need maybe one or two smaller versions with forward thinking individuals..
    • Exactly what happens when people are allowed to spend other people's money with essentially zero accountability. Personally I'd like to see NASA eliminated as a public entity - there just isn't enough ROI. Fund it through voluntary contributions and commercial ventures. Period.
      • Exactly what happens when people are allowed to spend other people's money with essentially zero accountability. Personally I'd like to see NASA eliminated as a public entity - there just isn't enough ROI. Fund it through voluntary contributions and commercial ventures. Period.

        As a geoscientist who has benefited immensely from using various datasets provided by NASA researchers and spacecraft, I have to completely disagree with you and assume you have absolutely no clue what you're talking about (which is m

        • As a geoscientist who has benefited immensely from using various datasets provided by NASA researchers and spacecraft, I have to completely disagree with you and assume you have absolutely no clue what you're talking about

          I hold that it would have been a far greater benefit to mankind to spend the money spent on the Mars Rover programs on, say, a bloodless, stripless glucose tester for diabetics, sonoluminescent equipment for oncology clinics or EM shielding for the nation's power grid.

          I continue to hold

      • Exactly what happens when people are allowed to spend other people's money with essentially zero accountability. Personally I'd like to see NASA eliminated as a public entity - there just isn't enough ROI.

        I would have to second the motion that you are talking out of your ass.

        As a working planetary scientist my field of research simply wouldn't exist without NASA. You can argue about the ROI for such things as the Mars Rovers, the Hubble Space Telescope, the Voyager missions etc. etc. But one thing is ab

        • without government and NASA there would be no such missions of exploration

          So where is the return on these missions of exploration? How is my life any better - or even different - because we now know that there are dust devils on Mars powerful enough to blow dust off of solar panels but not (yet) powerful enough to flip over a rover? How is anybody in this country better off now that we have lots of pretty pictures of distant specs of light?

          NASA has been a great sport about lying to the public about the

    • Re:Scuttle the Shuttle (Score:5, Interesting)

      by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Tuesday December 13, 2005 @08:57PM (#14252394) Homepage Journal
      Dude, they knew all this before they even fucking built it. The Shuttle was a decent (if suboptimal) design before the military got at the specifications. It had to carry and be able to deploy cargoes of a certain size to get the write-off from the military.

      The shuttle was supposed to be a prototype and we were supposed to move on. Instead, we got the shuttle, and it was "good enough" so we hung on to it. The fact that we A> discard the main tank, B> have to totally rebuild the SRBs, and C> have to rebuild the main engines, and all of this for each flight makes it just as cheap (if not cheaper) to use rockets as compared to the shuttle. The only thing the shuttle has that rockets don't is that it can be used to bring things back from space. Well, if those things are the right size and shape for the cargo bay, anyway.

    • Honestly I think America in general has lost its forward thinking ability. It's a reoccuring pattern. Each time America percieves a technological superiority, she becomes fat and lazy and it takes a big scare to get her to do anything.

  • And it makes me wonder... (Score:4, Informative)

    by eldavojohn ( 898314 ) * <eldavojohn@gma[ ]com ['il.' in gap]> on Tuesday December 13, 2005 @08:33PM (#14252235) Journal
    Historically, there have been many space flights with very few fatal malfunctions (Challenger and Columbia). There were even more test flights of the shuttle craft. Out of curiosity, has it always been a possibility that an "explosion could happen during flight" but with probability on their side, it didn't?

    What I'm trying to say is that you're trying to put a rocket into space with (almost) a piece of the sun on its backside. Aren't there always possibilities of explosions when what's powering you is, essentially, a controlled explosion?
    • Yes, but still using the shuttle in 2005 is akin to using canvas winged biplanes for general public transportation in 1960.

      Technology has advanced a ton in the last 35 years. It's incredibly stupid to use these obselete machines in anything but a museum.
      • A flawed analogy doesn't convince me, sorry, you'll have to try harder than that.

        Just because something is old doesn't mean it's obsolete. Nose cone fuselage shapes have remained the same.

        *sigh* I guess I'll fight bad analogy with bad analogy.

        Why are we still using the same electic engine design (thank you, Tesla) for all these years? It's akin to using the steam engine to power cars in 1960.

        Why don't you close your analogy and tell me what advances we have made in shuttle protection that are as
        • You are comparing fundamental technology with a huge complex beast that has a million do-dads and miles of wire and hurtles through the sky at thousands of miles per hour.

          You might as well say "well planes still use bernoulli's principles to fly"

          Anyway, you did admit your analogy was flawed. :)

          Regarding the actual advances, the main ones would be in materials science and in computing. High strength lightweight composite materials are revolutionizing industries left and right.

          The advances in computing are o
          • > You do realize the shuttle was designed with core memory, right?
            > Like hand-woven magnetic cores, for fuck's sake.

            You're shittin' me, right? Please say you are. Because. WOW. That would make NASA just about the only company with computer systems literally capable of dumping core.

            • It USED To have Core memory when it first started flying, it's all solid state now. The Shuttle does not have a lot of computing power, it really doesn't need that much to get to/from orbit. It's not trivial, but your desktop processor could certainly handle it.
          • Can you take your computer, power it off, stick it in the closet for a week, take it back out, plug it back in, turn it on, and have it instantly running the same software that was loaded in it when it was shutdown?

            Core memory disappeared because of cost and density issues, not because it was inferior technology. It was the appropriate choice when the AP-101 was designed.

    • A piece of the sun? I wasn't aware that the shuttle was lifting on a nuclear fusion rocket.
      • In my defense, I said almost--I know it's not a fusion rocket.

        But seriously, what temperatures does it hit? Something high probably. You know even commercial airliners have engines with combustions inside that are so hot that if they touched the sides of the engine, it would melt right through it. That's why there are crazy restrictive replacement rules on jet engines.

        • SSME Incredible Facts [boeing.com]

          When the hydrogen is burned with liquid oxygen, the temperature in the engine's combustion chamber reaches +6000 degrees Fahrenheit - that's higher than the boiling point of Iron.

          Guess that answers that question. That was one link away from the first result in a google search for "space shuttle main engine exhaust temperature" and very obvious. You lose! :D 6000 F is 3588 K.

          For comparison, the sun's surface temp is 6000 C (6273.15 K) and the core is 15 million kelvins. So it

          • Why don't you take a piece of metal or anything you can create (even an osmium/iridium composite of some sort) and apply 3588 K to it.

            Now why don't you take the same material and apply 6273.15 K to it. Notice a difference? I didn't think so. The reason I said almost is because for our purposes, it differs only in numbers and radiation emission.
        • "You know even commercial airliners have engines with combustions inside that are so hot that if they touched the sides of the engine, it would melt right through it." Not True at all, jet engines have a combustion chamber where the fuel burns, temps can be close to 1200K (2700 F), Titanium which is commonly used in Jet Engines and other high temp applications has a melting point at 1941K (3000 F). The afterburners on military jets are even hotter and the don't melt the afterburner components which IIRC ar
    • What's powering your car is, essentially, a (sequence of) controlled explosion(s). Sure, a rocket can never be 100% safe, but it can get close. Considering how rare manned space flights are (the average is what, a couple a year?) I'd say current performance is pretty poor. Sure, you expect this when you're working with new untested tech, but the shuttle shouldn't be that by this stage.
      • Unfortunately, with only a couple of spaceflights per year... the tech really is relatively untested. I mean, how safe would you feel about your car if automobiles as a whole had only been tested in their usual working environment at a couple of times per year since the 60s?

        Of course, there's also the issue that the current vehicles are really too old for continued use, particularly those intended for human transport/habitation, but what I'm trying to say is that we're still at the beginning of the space t
        • Unfortunately, with only a couple of spaceflights per year... the tech really is relatively untested. I mean, how safe would you feel about your car if automobiles as a whole had only been tested in their usual working environment at a couple of times per year since the 60s?

          Point, but if the components have been tested enough on the ground, the current amount of actual flights is more than enough to sort out any problems that come from the system as a whole. If cars had had thirty years of "lab" testing an

    • Don't forget Apollo 1 [wikipedia.org].
    • Aren't there always possibilities of explosions when what's powering you is, essentially, a controlled explosion?

      Of course not. What gave you that silly idea?

      More seriously, what's the point of your rhetorical question? If this oxygen leak had resulted in an explosion, I'm sure some people would unhelpfully note the "sun on its backside" bit. That doesn't explain why rockets blow up or don't blow up. And the idea completely fails elsewhere. For example, grain silos don't have controlled explosions as

  • So they found out about a potential serious problem 2 minutes after liftoff and they said nothing until 5 months later? Seems to me that NASA is trying to save face and not doing a good job at it. I've always been a strong supporter of NASA, but enough is enough, they just keep dumping billions of dollars into the space shuttle program and nothing constructive is happening.
    • No, they found out after the shuttle returned and after they could remove and gather and then interpret the data from the detection system. Possibly TFA is crap (BBC is no guarantee) but it's at least mentioned in or easily understood from this article: http://www.space.com/missionlaunches/ft_051211_di s covery_leak.html [space.com]

      Other things to mull over:
      - three of the six "catch bottles" (name of the measuring devices) showed completely normal values, one had "corrupt data" (don't ask me why, perhaps a mechanical fa

  • Spark + high O2 concentration = disaster (Score:4, Informative)

    by Robert Heinich ( 857844 ) on Tuesday December 13, 2005 @08:55PM (#14252373) Homepage
    I am surprised that no one has mentioned that we have had astronauts killed from this combination: http://en.wikipedia.org/wiki/Apollo_1 [wikipedia.org]
  • "...But two of the catch bottles indicated levels of gaseous oxygen in the compartment about two minutes into flight were higher than Nasa (sic) allows."

    They forgot to account for the fact the crew had just eaten an Arby's Roast Beef Sandwich.

    basiCreations Software [basicreations.com]

  • Where are the probes shuttling the oxygen to?
  • As I just happened to read today... http://www.counterpunch.org/grossman12132005.html [counterpunch.org] ...an in-flight explosion could be quite serious if that shuttle happens to be carrying large quantities of plutonium.
    • We go through this crap every time NASA launches something with an RTG (radioisotope thermoelectric generator). The lunatic fringe of the environmental movement starts whining about how plutonium is the most deadly substance known to man (bullshit), and how a launch accident could rain radioactive death on the planet (more bullshit).
    • I am amazed at the amount of stupidity that is displayed on this website and the websites that it links to. First of all let's list the inaccuracies:

      But NASA keeps insisting on plutonium power for space probes--even as the Rosetta space probe, launched this year by NASA's counterpart, the European Space Agency, with solar power providing all on-board electricity, now heads for a rendezvous with a comet near Jupiter.

      It's Pluto not Jupiter. Pluto. Pluto has practically no solar radiation reaching the plane

    • MARTY: Does it run on regular unleaded gasoline?

      DOC: Unfortunately, it requires something with a little more kick: plutonium!

  • Hmmm, how likely is this? Very, but risk is small (Score:3, Interesting)

    by Ancient_Hacker ( 751168 ) on Wednesday December 14, 2005 @08:26AM (#14255083)
    Lesse, we have a heat engine turning hundreds of gallons per second of cryogenic liquids into heat, then into a bazillion horsepower, a fair percentage of which gets turned into vibration. What are the chances of a bolted flange working loose, or a pipe fracturing, or a short temperature imbalance warping a pipe, valve, seal, or flange? What are the chances some piece of paper or other material was left in a hot zone, and the oxygen is just being boiled off the object? 500ppm is miniscule-- you can't get a flame or explosion until the fraction gets 100's of times higher. And a lot of the compartments are filled with inert gases, so it's even harder to start a fire.

Slashdot Top Deals

Thus spake the master programmer: "After three days without programming, life becomes meaningless." -- Geoffrey James, "The Tao of Programming"

Close