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Minor Technical Issue Aboard Shuttle Discovery 98

Posted by Zonk
from the i-would-probably-be-nervous dept.
IZ Reloaded writes "Space Shuttle Discovery has a problem with the pipeline for an auxiliary power unit that controls the shuttle's hydraulic steering and braking maneuvers. CNN reports that the pipleline is leaking 'fuel' at about six drops per hour." From the article: "The leak is more likely nitrogen, but there is no way of knowing that, so NASA is treating the problem as if the leak were fuel ... If it is fuel, the current rate is still 100,000 times slower than what would cause a fire ... Just in case, NASA will turn on the power unit with the leak early Sunday as part of its normal testing and then see if the leak rate changes. If it does, NASA may burn off the hydrazine and shut down the power unit before the shuttle returns to Earth to eliminate any fire hazard.'"
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Minor Technical Issue Aboard Shuttle Discovery

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  • solution (Score:4, Funny)

    by Anonymous Coward on Saturday July 15, 2006 @02:51AM (#15723898)
    Two words: Duct tape.
    • Re:solution (Score:3, Interesting)

      by megaditto (982598)
      Bad idea. As I recall from my college days, hydrazine is some really nasty stuff. The tiniest quantities will stink like rotting fish, way worse than triethylamine. Plus it's a potent neurotoxin, absorbed through skin or inhaled, with these 6 drops entirely enough to send the whole crew on a shroom-like trip (it would be a drug of choice on the street I think, if not for its HORRIBLE stench). MSDS just doesn't do this baby justice!

      Not nasty enough? Well, it's also highly explosive, hence the reason it is us
      • Just to show how the dangerous this really is, the hydrazine generators were deemed unsafe for submarines (but A-O.K. for the Space Shuffles, apparently). What next, dynamite sticks as flares?

        Atom [wikipedia.org] bombs [wikipedia.org].

        A lot more efficient than dynamite, but murder for your shock absorbers ;).

      • Space Shuffles

        It's ok.
        I think with the talk of shroom-like trips before, a Truffle fragment was stuck in your brain & just happened to come loose at that time.
      • Re:solution (Score:1, Insightful)

        by Anonymous Coward
        Mod parent up: both informative and insightful.

        I don't know how NASA can spin this as a minor issue. This is about as bad as a missing heat-protecting tile.
      • Plus its corrosive http://www.answers.com/topic/hydrazine [answers.com].

      • Hydrazine reacts in the precense of a catalyst such as silver or iridium, which is why combustion chambers of many reaction control rockets are lined with such. Hydrazine is semi-stable. It will breakdown in the precense of the catalyst or if it warms up to the proper point. If neither happens, you're fine. The engineers who actually know how the system is designed (ie, not you), and know where stuff can get into, where it might come into contact with a catalyst, or where it might warm up are the ones quali
    • Better use X-Treme tape [vyparproducts.com]. Have you seen this stuff? Silicone compound based tape, 600 psi tensile strength, self-fusing forming air-tight and water-tight seal, sticks to anything, withstands temperatures up to 500 F. Shuttle crew shouldn't leave home without it.
    • I don't think Macgyver is on board
  • Terminology (Score:4, Insightful)

    by pipingguy (566974) * on Saturday July 15, 2006 @03:00AM (#15723912) Homepage
    There are pipelines in space now? Cool.

    The leak is more likely nitrogen, but there is no way of knowing that.

    Excuse me? The shuttle must be one of the most redundantly-instrumented efforts ever built and they don't know what's leaking?
    • by TrappedByMyself (861094) on Saturday July 15, 2006 @03:21AM (#15723939)
      Excuse me? The shuttle must be one of the most redundantly-instrumented efforts ever built and they don't know what's leaking?

      Obviously not. I guess some rogue foam disabled the giant blinking "HYDRAZINE LEAK" and "NITROGEN LEAK" signs, so they're lost up there. You better call NASA and tell em what's what.
    • Re:Terminology (Score:3, Insightful)

      by helioquake (841463) *
      It's not easy to crawl into the conduit and locate a leak. Let alone checking what the substance is. (What do you want? Let them lick and taste it to see what it is?)

      I'm more bothered by the use of the word "drop" here if you ask me.
    • by leathered (780018) on Saturday July 15, 2006 @05:54AM (#15724143)
      There are pipelines in space now? Cool.

      They're the tubes that makes the intarweb run, how do you think all that data gets to the satellites and back?
    • In space no one can smell you scream.

      I thought everyone knew that.
    • Re:Terminology (Score:5, Informative)

      by NOLAChief (646613) on Saturday July 15, 2006 @11:02AM (#15724758)
      There have been pipelines in space since the beginning of the use of liquid fueled rocket engines. Propellant has to get from the tanks to the engines somehow...

      They mean it, there really is no way of knowing. They know there's a leak based on pressure readings. They know it's not an instrumentation issue because those pressure readings are redundant (i.e. if one sensor started trending down and it's backup didn't, then the sensor's bad). Based on those same pressure readings they know what the leak rate is (drops per hour was probably the guy's attempt at making it make sense to the layperson by analogy to a dripping faucet. Sadly that analogy seems to have fallen flat.) Since the fuel tank (hydrazine) is connected to the pressurant system (nitrogen), the entire system is at the same pressure, so since there is a leak, every pressure sensor monitoring the system is trending down.

      (Time for my own bad analogy) Let's say you've got a Super Soaker with a pressure gauge in the water reservoir. You pump up the Super Soaker and put it in a box so that the only thing you can see is the pressure gauge. Now, somehow a hole forms in the reservoir. Because you can't see the reservoir, you don't know if it's your fuel (the water) or the pressurant (the air you pumped into the thing) that's leaking, but you know from the decreasing pressure reading that there's a leak present. That's essentially what's going on with Discovery. Hence, they're playing it safe and assuming the leak is fuel, when more likely it is the smaller nitrogen molecule that's escaping the system.

      • I'm a piping geek, thus my problem with terminology. "Pipelines" are large bore cylindrical structures that convey large quantities of fluids. What the shuttle uses is piping, not pipelines. To some of us there is a difference.
    • its not pipelines, its tubes.... you should have know that the space shuttle runs on many different internets,in fact i just sent one to the shuttle today. i just hope my internet doesent get lost in all those tubes
    • The nitrogen is used to pressurize the hydrazine tanks to feed the reaction control system. It's pretty simple. Rather than have pumps that would be corroded by the hydrazine, they just warm up the nitrogen a little bit and the pressure increases. They know the pressure is dropping, but they're not sure if it's because they're losing nitrogen or losing hydrazine. I suppose they decided it wasn't worth the extra effort, cost, complexity, and weight to be able to isolate the tanks soley for the purpose of det
      • Thanks. I've done a fair amount of work with pressurized and cryogenic gases, but I didn't know the details in this situation. It makes sense to me now.

        This is how most cryo installations work (eg. o2 for hospitals, n2 for industrial applications). Pumping cryogens can be a real problem, and most users don't need extremely cold liquids so ambient vaporizers [thermaxinc.com] are used.
  • by Megaport (42937) on Saturday July 15, 2006 @03:04AM (#15723917)

    Hydrazine [wikipedia.org] is nasty stuff but it is just one of the dangerous checmicals aboard the shuttle.

    When Columbia broke up, it was the possible presence of Hydrazine from the APUs that make the Texas Dept of Health issue warnings about approaching shuttle debris.

    The problem with spaceflight is that everything is so close to the edge. Performance requirements that can still leave a good safety margin mean that simpler and safer methods are often inadequate. Consumers don't have the same risk/reward ratio as people who sit on top of rockets for a living.

    -M

    • When Columbia broke up, it was the possible presence of Hydrazine from the APUs that make the Texas Dept of Health issue warnings about approaching shuttle debris.

      Don't worry, since our Missile Defences tests showed yesterday ( http://www.lcsun-news.com/news/ci_4044160 [lcsun-news.com] ), at any sign of danger we can blow that WMD shuttle right out of the sky.

      ____
      Laugh, dammit.
    • Consumers don't have the same risk/reward ratio as people who sit on top of rockets for a living.


      Who in turn don't have the same risk/reward ratio of those who get strapped to the sides of a rocket.

      Myeh, personal views on the need to redesign our approach to space (i.e. get a new class of ship) aside, I'm hoping for a boring trip and landing for the shuttle.
    • All of this is especially true if your launch vehicles are made in the USA.
    • Hydrazine wasn't chosen for performance. It actually has a rather low ISP. It was chosen for reliability. The reaction control jets have to fire repeatably far more times than other types, and usually while cold. In this case, NASA uses a hypergolic form; one which spontaneously combusts in the precense of another chemical. The two are released simultaneously into the reaction control jet and voila, fire.

      NASA would love to develop a methane based version with a much higher ISP and less handling risk, but
  • by Anonymous Coward on Saturday July 15, 2006 @03:07AM (#15723921)
    Seems off that only APU1 drives the landing gear, with a backup of pyrotechnics...

    "APU 1 is the only hydraulic system that can deploy the shuttle's landing gear. If APU 1 is out of action, pilot Mark Kelly would have to manually fire pyrotechnic charges to deploy the gear."

    http://www.spaceflightnow.com/shuttle/sts121/06071 4mplm/ [spaceflightnow.com]
  • STS-9 APU Fire (Score:5, Interesting)

    by Aglassis (10161) on Saturday July 15, 2006 @03:15AM (#15723934)
    STS-9 came in with an APU on fire. Here is a video [johnwyoung.org].
    • Mod up for informative! Nice vid too.

      But are you saying this makes it less or more worrying?...
      • Re:STS-9 APU Fire (Score:3, Informative)

        by Aglassis (10161)

        But are you saying this makes it less or more worrying?...

        I would say that it is less worrying for the astronauts, and more worrying for the engineers on the ground. The astronauts know that a fire has occurred before and that it wasn't deadly (though the circumstances are different). Mission control knows a fire has occurred before and doesn't want to take the chance again!

        On a side note, the two APU fires (I miswrote in my previous post--there were two!) were minor issues for STS-9 compared to the 2 fai

        • The astronauts know that a fire has occurred before and that it wasn't deadly

          An example of the syndrome which led to them tolerating foam strikes, right up to the point where they lost an orbiter.

          I can't see in TFA what the primary indication is. It can't be a loss of pressure because this would tell them what is leaking.

          • An example of the syndrome which led to them tolerating foam strikes, right up to the point where they lost an orbiter.

            Actually, no. It was always the people on the ground tolerating a situation. While the astronauts certainly have some say in what happens in the space program (i.e. not shaving themselves bald for fire protection), mission control is usually the one who makes the major decisions, especially when there is some discrepancy (and this always occurs--like the 1202 executive overload in the Apo

            • Whoops, I gave the wrong link. It is still useful information about the APU problem, but here [orlandosentinel.com] is the correct link (from which I quoted).
  • I wonder if those on board would call a fuel leak a minor technical fault?
    It may be slow now, but in my experience leaks tend to get worse...
    • Re:Minor? (Score:1, Insightful)

      by Anonymous Coward
      "but in my experience leaks tend to get worse.."

      You are an experienced astronaught?
      • lol
        yes. Well... no. But I've seen leaks before, and they tend to get worse. Erosion and corrosion increase with flow-rate, causing an unpredictable runaway effect.
  • I know its alreay too late for the space shuttle, but i wonder how much it would have cost them just to modernize all of the shuttle parts. Or at least make all the tubing and pipes out of duct tape. If they sell the space shuttles in fifty years or so anybody want to try?
    • Well, you have to consider, this is NASA. There are certain procurement and testing processes involved. By the time they could get the whole thing sorted out, the shuttles would be rusted-out hulks. Or all burned up, as the case may be. I exaggerate, but only slightly. I'm sure it wouldn't be a cost-effective proposition.
    • We could just call Xzibit and have him Pimp their Ride.
      I want a shuttle that hops , man!
      After a clean landing, the Air Force could have a band play "Low Rider" as it taxis down the runway.
      Would fuzzy dice be overkill?
    • I wish it was easy. But redesigning manned flight systems is not, no matter how simple the change seams, simple. All changes have to go though at least three review boards. The people that populate those boards do not necessarily know all the details of the hardware. It takes time to teach them what criteria is important and what is not.

      Once you're though that, then the hard part starts; electrical test, vibration tests, "chemical off gassing test", Electro static discharge (ESD) tests, performance tes
  • Overconservatism (Score:2, Interesting)

    by mcrbids (148650)
    NASA is crippled. Rather than cover the achievements of each mission, they cover the lack of failures. It's a no-win situation. If they screw up ANYWHERE, they look terrible. If they make it back ok, they wasted a ton of money on... what again?

    In the media, I've heard all about how they made sure the stupid thing can land, on at least 3 media sources. But WTF is the reason they launched? What are they up there for, other than to make it back alive? I could do that on a Mooney [mooney.com] for alot less money and with a
    • You marched on the streets? Did your mother know?
    • "Give me a reason to get excited, or stop spending my damned tax dollars."
      The reason is this. If they don't go and get rid of some of the rubbish building up in the space station the Russians are going to drown. If you want to get exited then cut off your rubbish collection for a couple of months. I have no doubt you will feel highly exited at the end of that time when the rubbish truck comes. I do find it strange that they don't just bag it up and jettison it into the atmosphere though...
      On another not
    • Re:Overconservatism (Score:4, Interesting)

      by Anonymous Coward on Saturday July 15, 2006 @05:03AM (#15724077)
      You can't escape from taxes, and I'd rather see them spent on NASA than on Iraq.

      Did you ever watch one of those news conferences held with the astronauts/mission management team representatives? ALL questions somehow related to a concern for safety and NONE are actually asking whatever the crew have done that day. NASA is surely making a big deal on re-entry, but it's the media is making it sound like it's gonna be another Columbia.

      The overwhelming concern on safety is exactly what got me excited about these couple of "return-to-flight" missions. NASA is trying to MOVE FORWARD with the construction of the ISS while trying their best to keep the construction workers safe. If they slip and the program stalls it will not only be years and years of your and my tax dollars that go down the drain, but also investments from Russia, Japan, Europe and other international partners. It is ALREADY an international effort. It is a sunken-cost mentality and it is make-or-break for NASA.

      Quit acting like you don't care about the lives of those astronauts if they are given in the name of "progress". Everything that NASA does to protect them IS "progress". You protested furiously about the not having any more dead soldiers in Iraq didn't you? What makes you think it is any different in space?
      • Re:Overconservatism (Score:1, Interesting)

        by Anonymous Coward

        I'm guessing that you don't deal with NASA on a daily basis, as I do. The S in NASA doesn't stand for shuttle! The tail is wagging the dog here and the shuttle is becoming the main focus of both mind and dollar at NASA.

        The shuttle was designed for cheap quick turnaround flights, but in reality it costs as much as one billion dollars per launch (for launches where it doesn't blow up)? And what space science do we gain from them? Not much; considering that for that $1B, you could build 3 MIDEX-class instr
      • You can't escape from taxes, and I'd rather see them spent on NASA than on Iraq.
        You're talking as if NASA's funding is syphoned off from Iraq's funding. NASA was soaking up money long before the Iraq war, and will continue to do for long after. All for very little tangible gain, other than non-stick frying pans.

        It's estimated that NASA costs the average American tax-payer over $100 a year.
      • Pardon my sarcasm, but if NASA were really interested in "protecting" their astronauts, then they wouldn't have sent them into space.

        My take is that the slower they go, the more unsafe they become. That's because a higher launch rate means more safety data and flight-tested components. It also means that the vehicles age less between launches. Then you add in the facts that no matter how cautious NASA is, the Shuttle has somewhere in the neighborhood of 1% that it won't come back and that the Shuttles cos

    • I would say well said, but it wasn't particularly. But I like that you said it.

      At a time when waste, recycling, energy crisis, wars to 'solve' the energy crisis, and other related topics are of paramount importance, such missions seem ridiculous. And a waste of money to boot.

      Let just hope the current escalations are not going to grow, and further illustrate the need for strategic prioritisation.

      If you want to stride forward, like the great nation you are/were/could be - then how about using nano
    • Give me a reason to get excited, or stop spending my damned tax dollars.

      Speaking of this, how much do NASA currently cost American citizens per year? Even better, is there a web site where one can see how the distribution of tax money change from year to year in a reasonably accessible form? I'm not American and have been wondering of this now and then when the subject is brought up.
      • Re:Overconservatism (Score:3, Interesting)

        by icebrain (944107)
        FY06 NASA budget: $16.5 billion

        US population: ~ 300 million

        Total cost, per person: ~ $54.84

        About 25-30% of the population is too young to pay taxes - that leaves around $71 per taxpayer.

        To put this in perspective (albeit with 2004 numbers):

        NASA budget allocation: $15.5 billion

        Department of Education: $53.1 billion (29.4b for primary/secondary, 15b for higher ed., 1b for vocational)

        Housing and Urban Development: $31.3 billion

        IRS (tax collectors): $10.4 billion

        Foreign aid: $17.1 billion

        Department of Agricult
    • According to NASA's website [nasa.gov], the Shuttle's mission involves testing a lot of safety stuff. This would carry over to future Shuttle missions, as well as whatever the next vehicle is. I'd rather a spend a few billion on upgrades now than billions later on replacement vehicles.
    • "Give me a reason to get excited," O.K. !!! I have a reason why an all American lad (or lass) might get excited. They are spending your "damned tax dollars" to send those poor folks up there and they don't equip them with a tool-box which contains a roll of DUCT TAPE . You lads (and lassies) need to do something about this kind of negligence, I think. After all DUCT TAPE is what holds the American empire together.

  • by Seiruu (808321) on Saturday July 15, 2006 @05:12AM (#15724087)
    A leak in a "gas tank" is a minor technical issue? :p

    "Hey there cowboy, word goes around that there's something wrong with my car."

    "Nah sir, just a little scratch."

    "Ah if it's just a scratch then I can live with it."

    "Yes sir, just a bit of gas leaking through that "scratch", so you might want to cut down on that smoking sir."
    • Minor as in "can probably make it home without exploding", not minor as in doesn't need attention.
    • If you have a car that runs on gasoline (i.e. spark ignition high volatility fuel) you may already have minor gas leaks and you are probably losing a certain amount of fuel through evaporation, unless you happen to be in very high latitudes in the Southern hemisphere. Gasoline is so volatile that it is very hard to spot small leaks. In cars and trucks this is rarely that important so long as the engine compartment is well ventilated, but there is a reason why marine approvals bodies discourage inboard gasol
  • It's nice to know they can detect leaks so small they're "100,000 times slower than what would cause a fire." What is that, about a few molecules a second?
  • Explosive bolts (Score:3, Informative)

    by OriginalArlen (726444) on Saturday July 15, 2006 @06:46AM (#15724206)
    The write-up missed the important angle that if they decide to power down the possibly leaky APU, they'll have to use explosive bolts to lower the undercarriage. That's never been used in flight before. That doesn't mean it won't work, of course, but it will make the re-entry and landing a little more interesting than usual.
    • Ley me get this straight... it's leaking HIGHLY explosive hydrazine & they're planning on firing EXPLOSIVE charges to lower the landing gear... hmmmm....
      • If it will make you feel better, we can call them gas generators. It's the same thing, just with a friendlier name. See your automobile's air bag for an example.
  • I wonder if the astronauts can taste or smell it to see what it is.
  • The shuttle has 3 auxillary power units. One is necessary to land. They are routinely tested while in space. If one fails they land as soon as possible. The APUs are not small, they are powered by a 100 horsepower turbine which is turned by decomposing hydrazine over a catalyst. Sometimes on good movies of the shuttle after it has landed you can see the heat waves from the hot gases (nitrogen, hydrogen, and a little ammonia) from the decomposing hydrazine coming straight up from the shuttle.

    The larger
    • by woolio (927141)
      Believe it or not there are people who believe that low levels in the blood is an anti cancer agent.

      Are these the same ones that believe low levels of fluoride is an anti-cavity agent?
  • Minor Technical Issues is no eye catcher :)

The bogosity meter just pegged.

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