Could a Dirty Rag Take Out a $2 Billion Satellite? 297
An anonymous reader writes "The alleged rescue of a U.S. military communications satellite underscores some of the weaknesses in U.S. space efforts. Quoting: 'The seven-ton “AEHF-1,” part of a planned six-satellite constellation meant to support radio communication between far-flung U.S. military units, had been in orbit just one day when the problems began. The satellite started out in a highly-elliptical, temporary orbit. The plan was to use the spacecraft’s on-board engine to boost it to a permanent, geo-stationary orbit. But when the Air Force space operators at Los Angeles Air Force Base activated the engine, nothing happened. The Government Accountability Office would later blame the failure on a rag left inside a fuel line by a Lockheed worker.'"
Lockheed gonna get sued? (Score:5, Insightful)
Seems like the gov't should sue lockheed for failing to deliver the working satellite as contracted.
Hopefully that'll happen (which will probably leave that worker jobless) and we'll get some of our tax dollars back.
Shhh... I can dream!
Re:Lockheed gonna get sued? (Score:5, Informative)
Re:Lockheed gonna get sued? (Score:5, Funny)
Yes, the gov't will have to pay for that space-rag now. Lockheed forgot to bill them for it.
Re:Lockheed gonna get sued? (Score:5, Funny)
Yes, the gov't will have to pay for that space-rag now. Lockheed forgot to bill them for it.
The bill also included the fines levied by the TSA for failing to file an export declariation on the space rag.
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It's funny (Score:2)
Because it's true.
Re:Lockheed gonna get sued? (Score:5, Funny)
TFA states that they are seeking compensation from Lockheed. Hopefully, that'll happen without an actual suit.
That would be quite the space suit.
Re:Lockheed gonna get sued? (Score:4, Insightful)
Seems like the gov't should sue lockheed for failing to deliver the working satellite as contracted.
Hopefully that'll happen (which will probably leave that worker jobless) and we'll get some of our tax dollars back.
Shhh... I can dream!
Lockheed wouldn't piss off their biggest spender. They'll pay back in the form of a "credit" for some kind of services that have the highest margin for Lockheed. The guy who screwed up and his boss will get fired for sure, and then they will have some business analyst examine their QA process and add a little redundancy in the inspection policies. Nothing to see here folks.
Re:Lockheed gonna get sued? (Score:5, Insightful)
Seems like the gov't should sue lockheed for failing to deliver the working satellite as contracted.
Hopefully that'll happen (which will probably leave that worker jobless) and we'll get some of our tax dollars back.
Shhh... I can dream!
Lockheed wouldn't piss off their biggest spender. They'll pay back in the form of a "credit" for some kind of services that have the highest margin for Lockheed. The guy who screwed up and his boss will get fired for sure, and then they will have some business analyst examine their QA process and add a little redundancy in the inspection policies. Nothing to see here folks.
Isn't that what should happen? I mean, when did the world suddenly decide that anytime anyone makes an honest mistake they should be crucified for it forever? If there is restitution for lost funds as well as improvements to try to prevent a repetition of the same problem, shouldn't everyone involved be satisfied? I'm fairly certain that the OP's hope that we all get some kind of tax refund is probably not going to happen, and even if it did, you'd be talking about a few dollars per person at most.
Re:Lockheed gonna get sued? (Score:5, Insightful)
I mean, when did the world suddenly decide that anytime anyone makes an honest mistake they should be crucified for it forever?
Forgetting a rag is an honest mistake. Failing to plan for honest mistakes by implementing the appropriate checks into your process is negligence.
Re:Lockheed gonna get sued? (Score:4, Insightful)
I mean, when did the world suddenly decide that anytime anyone makes an honest mistake they should be crucified for it forever?
Forgetting a rag is an honest mistake. Failing to plan for honest mistakes by implementing the appropriate checks into your process is negligence.
The engineer following the process is not necessarily the person that created the procedure. Also even if a procedure is in place double failures do occur - they are just less likely.
I love the way so many people are willing to judge that a man should or should not be fired based on 3 minutes of reading a slashdot story. Really enhances my faith in human nature. Hope none of you ever sit on a jury. What disciplinary action if any should be faced by various staff involved is something that would require at least weeks of investigation, IF you want to go in that direction and waste the time on a witch hunt instead of just fixing the issue.
Re:Lockheed gonna get sued? (Score:4, Insightful)
49% don't actually pay income tax
Because they didn't make any money above federal poverty rates....but hey, don't let details get in the way of a perfectly overused irrelevant statistic.
the top 1% paid 40%
When they account for 50%+ of the income, the should be paying *more* taxes, not less.
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The to 5% make 38%. But this is Slashdot, it's not as though you guys are going to let something like MATH get in the way of Socialism.
Re:Lockheed gonna get sued? (Score:5, Insightful)
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It is relevant that 49% don't make money above the poverty line. Fix that problem
That problem was fixed. So they moved the poverty line up, and it will keep being moved every generation, because it's a good political football.
Look around you and see whether America seems to have a starvation problem, or an obesity problem. Real poverty, as would be recognized in most of the rest of the world, is almost absent in America.
No matter what you do, 20% of people will be in the bottom 20%, you know. The best system to avoid too much wealth concentration is to change inheritance taxes to be i
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Considering the top 1% control 33% of the wealth in the country, and the bottom 50% only have 2.5%, I'm pretty OK with that distribution.
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... Not to mention that almost everyone in the US is in the top 1% worldwide.
Hmm...scale does not compute. (Score:5, Interesting)
Must be a really small rag or really big fuel line. Seriously, how would this happen? It's a freaking satellite engine, not the shuttle main.
Re:Hmm...scale does not compute. (Score:5, Funny)
Re:Hmm...scale does not compute. (Score:5, Insightful)
Yeah. Damn it people! This is just rocket science, not brain surgery!
Actually, compared to rocket science, brain surgery is a walk in the park [youtube.com].
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I wonder what that says for Theoretical Physics.
http://www.youtube.com/watch?v=lVPsBmhgjTk [youtube.com] [big bang theory]
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Dammit jim I'm a doctor, not an engineer.
Re:Hmm...scale does not compute. (Score:5, Informative)
You can use tiny squares of cloth, impregnated with cleaning solution, to clean the inside of valves and metal lines - gets rid of metal filings which are left over from the boring process.
Quite easy to leave one behind. Which is why there are processes in place designed to prevent such issues.
Re:Hmm...scale does not compute. (Score:5, Interesting)
You can use tiny squares of cloth, impregnated with cleaning solution, to clean the inside of valves and metal lines - gets rid of metal filings which are left over from the boring process.
Quite easy to leave one behind. Which is why there are processes in place designed to prevent such issues.
So, they built a tool to make sure the rag was removed. Then they built another tool to check that the first tool was removed...
More seriously, why wouldn't groundside testing notice that there was a rag in the line?
Re:Hmm...scale does not compute. (Score:5, Informative)
More seriously, why wouldn't groundside testing notice that there was a rag in the line?
Yup, why wouldn't it?
Obviously it didn't. Multiple times. In multiple different situations - this isn't the first space mission to be ruined because of something left where it shouldn't have been.
The obvious answer to your question might be because it didn't block anything during testing, so there was the appearance of nothing wrong. Turn on the fuel flow, after the experience of the launch, and it might have been jostled free from wherever it had chosen to hide - from there it might be a short ride to a bottle necking point such as a crimp in the line, a sharp bend, or a valve, and thus begins the blockage.
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I've dealt with people at the GAO, they have a lot of expertise in house on many subjects, and aren't afraid to seek advice externally to come to decisions. It's one of those branches of government that it's actually nice to have.
Blowing out lines with air... (Score:3)
Billions of dollars in technology, but nobody with an air nozzle hooked up to an air compressor found at any car mechanic's shop to blow out a fuel line.
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Re:Hmm...scale does not compute. (Score:5, Insightful)
More seriously, why wouldn't groundside testing notice that there was a rag in the line?
Some of these positioning rockets are single-use. If you test one you have to build another to replace it. And then test it. And then.....
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One space industry insider, who spoke with The Diplomat on condition of anonymity, says lapses like the forgotten rag indicate a lack of experience in the lower ranks of U.S. space contractors. âoeIt was probably a mix all too common in the USAF programs: 80-year-old PhDs and 20-year-old college gra
Re:Hmm...scale does not compute. (Score:4, Informative)
How do they know a rag was left in the fuel line? Do they have a sensor in the fuel line that checks for the presence of rags?
I don't know about this case, but AFAIR NASA required forms signed in triplicate saying that any tool taken into the shuttle was later removed from it. Perhaps there's similar tracking in this case and a check showed up a rag that wasn't signed out for being removed.
It seems to be a common problem, I'm sure I remember a couple of rocket launches which were blamed on rags in the fuel lines.
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If it's a rag small enough to scrub the inside of a fuel line, it could easily go unnoticed on its way onto the assembly platform. Or, if one was too large, it could have been sectioned and still taken out as "one rag." But in any case, signed in or signed out, how hard is it to test whether or not the line is partially or fully plugged? Put a controlled pressure on one end and measure flow rate on the other.
Re:Hmm...scale does not compute. (Score:4, Interesting)
Catching every little thing that might gum up the fuel lines during assembly, testing, and cleaning seems like it could be a genuinely hard problem. Doing a combination pressure test/gas flush seems like it would be a cheap, simple, brute-force solution to that entire class of potential problems...
Check the logs? (Score:5, Funny)
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They tried to get a form check requisition going, but couldn't get the necessary signatures in time for launch.
Re:Check the logs? (Score:5, Insightful)
Probably the same reason why things end up being left inside of patients. Accidents happen, even if it's something that should never happen because it was on the checklist.
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An audit of procedures after the Challenger disaster revealed that this can actually cause the problem it's attempting to solve. When you require three people to sign off that something has been inspected, one day an inspector is a bit rushed and needs to finish by 4:30 to make it to his child's school play. He figures since two other people will be inspec
Re:Hmm...scale does not compute. (Score:4, Insightful)
No, not paper. These things are assembled in cleanrooms, in which ordinary paper is not allowed, due to the particles/fibers it sheds. Cleanroom cloths are usually lint-free polyester cloth squares about 8 inches on a side, IME.
The answer appears to be a yes. (Score:5, Interesting)
And yes, I went with the car analogy right from the start. Deal with it.
Re:The answer appears to be a yes. (Score:4, Interesting)
Exactly! Any old blockage could prevent fuel from getting through the fuel line. Same with the oxidizer. Even smashing a bug under an electrical component could cause a failure.
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bugs being smashed in electical components has already happened, lots of times in history.
Here's one of the first properly documented cases of it, from 1947:
http://www.history.navy.mil/photos/images/h96000/h96566k.jpg [navy.mil]
Photo #: NH 96566-KN (Color)
The First "Computer Bug"
Moth found trapped between points at Relay # 70, Panel F, of the Mark II Aiken Relay Calculator while it was being tested at Harvard University, 9 September 1947. The operators affixed the moth to the computer log, with the entry: "First actual case of bug being found". They put out the word that they had "debugged" the machine, thus introducing the term "debugging a computer program".
In 1988, the log, with the moth still taped by the entry, was in the Naval Surface Warfare Center Computer Museum at Dahlgren, Virginia.
Courtesy of the Naval Surface Warfare Center, Dahlgren, VA., 1988.
NHHC Collection
Re:The answer appears to be a yes. (Score:5, Funny)
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Is it the same 5 dollar wrench that was used to beat the password out of the programmer of another sattelite that was hacked?
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What if someone made a smaller wrench? You seem to be assuming there is a fixed size of 'wrench', and a lower bound on it.
Since I'm betting neither of us has helped to assemble a satellite, I'm betting neither of us has any idea of the specialized tools involved. How do you know it's not one of these [edm4.com]?
I seem to remember wrenches from my mechano set when I was a kid which would fit into the cylinder of most car engines
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Really wow. That kinda surprises me. Other than track side pit crew work, which generally would not be invasive enough to the point of removing the head why would someone be working so quickly and careless not to turn the engine over by hand once before applying the starter?
Seriously after any job that requires removing the cams from their bearings you should probably be turning the engine through at least on revolution by hand just to make sure everything operating freely.
Re:The answer appears to be a yes. (Score:4, Informative)
Most starters aren't strong enough to bust up a wrench or socket. Take out a plug maybe, possibly bend a valve, but in all likelihood, the motor would turn the engine till contact and stop.
That is assuming you are hitting the engin with the starter before hooking up the fuel and plugs. Which is usually a good idea to get the oil pump primed and heads lubricated firing it up.
That said, I have a number of wrenches that could easily fit in a cylinder with the piston at BDC. A GM 350 for instance, has a 4" bore and 3.48" stroke. On the diagonal that gives you over 5 1/4" clearance at BDC, not including the combustion chamber in the head.
9-11mm wrenches and 1/4" wrenches are common tools under the hood. Wiring brackets, trim plates, grounding lines, battery terminals, oil pan bolts, valve cover bolts, etc... They all fall into that size range.
-Rick
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Ok, not exactly a car, but I bet a bunch of wrenches could fit in a cylinder from one of these: http://www.archithings.com/cat-c175-engine-refined-drive-train-and-efficient-body-designs-for-797f-mining-truck/2009/10/23 [archithings.com]
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You obviously have little or no experience with engines and wrenches.
I have in my possession a canvas tool-pouch containing 12 ignition wrenches that can easily fit inside the cylinder, and has done so many times over the past 4 decades. That's 12 wrenches at a time, and the pouch that has fit totally inside of cylinders many times. (handy place to temporarily hold things)
Somewhat in your defense, I will admit that there are few times you need that small of a wrench around an engine when the heads are remo
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How many satellites have you assembled? For me, it's zero.
But, I've seen people clean the fuel line on RC helicopters ... we're talking about something about 1 inch square on the end of a little metal doo-hickey.
It is not inconceivable that we're not talking about a big old smelly rag here.
Why has Slashdot suddenly fallen into the trap of "I've never seen one so it can't possibly exist"? Serious
Re:The answer appears to be a yes. (Score:4, Informative)
I have assembled zero satellites. But back in my military contracting days, I did the electronics for several military applications and was present when satellites were built. The boosters on those things are fairly small, and the fuel lines tend not to be big enough to stuff into what we think of as a rag. Maybe a cleaning tool or some other implement. I think whomever wrote that was either lazy or didn't fully understand what they were writing about.
> Why has Slashdot suddenly fallen into the trap of "I've never seen one so it can't possibly exist"?
Have we so soon forgotten that us slashdotters come from a variety of backgrounds? For instance, legal articles are often responded to by actual lawyers in this group. There are actual astronomers, actual physicists, actual biologists, and I'm certain, actual rocket scientists, who read and participate in Slashdot. We're not all gamers living in our parent's basement. Although there are some.
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You have to be joking or you've forgotten what we're talking about. This is an apogee kick motor (to use GPS parlance) to take a 2 ton space vehicle to a circular 22,000 mile orbit. GPS, having half the orbit and half the weight, has an AKM which is not small. It's huge. It has to be due to the amount of firing it's intended to do. I tried Googling an image to show my point, but unfortunately, the AKM is on the "non-sexy" side of the SV and, hence, no photos. We're not talking about .5 pound stationke
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anything can take out a satellite (Score:5, Funny)
That's why it's rocket science.
Test Sequence? (Score:4, Interesting)
Who puts an engine together without a test fire? Seems to me that some simple checks would have prevented a very big waste of funds and effort. I guess it won't be a total waste if they can learn from it.
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Actually, the Hubble mirror isn't supposed to be flat, its shape is a particular function. It was actually manufactured exactly to spec, but the spec was wrong.
Re:Test Sequence? (Score:4, Informative)
Actually, the Hubble mirror isn't supposed to be flat, its shape is a particular function. It was actually manufactured exactly to spec, but the spec was wrong.
Actually,the hubble was spec'd to be a conic constant of p=-.0023, but was polished only to p=-.0139 (i.e. over hyperbolic). The error was due to a problem with the tester. The null reference element was out of position by just over a millimeter. The interesting thing is two other testers reported that the mirror was wrong, but they were ignored because they were not the 'primary' testing instrument. You are correct that it wasn't supposed to be flat, but it definitely wan't built to spec.
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Lots of failures there. (Score:5, Insightful)
Assembly failure - leave a rag.
Inspection failure - did not check for rag.
Pre-flight final inspection - still did not find the rag.
Wow, complete failure all the way down the line from assembly to mating with the launch vehicle.
Re:Lots of failures there. (Score:5, Funny)
XXI century new space programs motto : It's failures all the way down, man!
Re:Lots of failures there. (Score:5, Interesting)
It reminds me of those surgery horror stories where the surgeon or staff leaves behind clamps and sponges inside the persons body.
Shit happens. All we can really do is our very best to try and prevent it, but ultimately, we're human and prone to mistakes.
Re:Lots of failures there. (Score:5, Interesting)
> It reminds me of those surgery horror stories where the surgeon or staff leaves behind clamps and sponges inside the persons body.
Funny you should mention that. I had emergency surgery last year for severe traumatic internal bleeding (won't bore you with the details -- or maybe I already have) and things happened so quickly that they did not have enough time for an instrument inventory. (Apparently it's someone's job to keep track of how many tools get used and then count them before final suture.) So after they got me stable they ran me back through x-ray to look for stuff. Didn't find anything, fortunately.
But really -- it's not that much of a horror story, they just have to open you back up at some point to retrieve the objects. It's not something you want to have happen, but it's a fairly well known procedure. Horror stories to me are things like taking off the wrong limb [1] or prescribing catastrophically wrong medication.
[1] Before I went in for knee surgery, the doctor gave me a sharpie and had me mark the correct knee. Just in case.
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It does make me curious as to how big the rag and fuel line are. Also makes a great juxtaposition with the story immediately below on the home page, The Challenges Of Building A Mars Base [slashdot.org]!
Re:Lots of failures there. (Score:5, Interesting)
Actually pre-flight final won't catch that kind of thing; it's already buried in the system (and you don't fire thrusters on a flight unit prior to launch). This is likely one of those cases where a scrap of cleaning"rag" was torn off within the path in an area not visible at either end and went unnoticed. To save money, a visual of the system prior to final assembly was determined to be sufficient and the endoscope procedure was eliminated, saving several thousand dollars (combined on all the lines). Sure, in hindsight a compressed air test would have been sufficient, but it's a little late to play what-if now.
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Sure, in hindsight a compressed air test would have been sufficient, but it's a little late to play what-if now.
Except that devising a simple $1000 test might save the next $2,000,000,000 satellite. Extra points if you can add to or replace an existing test that tests multiple systems sufficiently.
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The test was devised, mostly likely. There are hundreds - no, probably tens of thousands - of tests on this craft. You can probably trace every single raw material element back to where it was mined, refined, billeted, shipped, stored, manufactured, machined, binned, tagged, selected, gaged, installed, torqued, tested, and approved for flight. Every single time a human touches a part it costs $100 (well, that was a decade ago, it's probably $200 now).
The anal retentiveness of the work flow on a satellite is
Re:Lots of failures there. (Score:5, Informative)
You left out Slashdot summary failure.
FTFA
"On Oct. 24, AEHF-1 reached its originally planned orbit. Testing began soon afterward. The Air Force expects to bring the satellite into service in March. Meanwhile, two more AEHFs are slated to launch in 2012."
They got it into the correct orbit over two months ago using the small thrusters.
In other words...
More sensationalistic headlines to get clicks and comments from the new Slashdot.
Really? Oh and the answer is "no a dirty rag did not take out a 2 billion dollar commsat."
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probably.
But by then they may have a better replacement ready.
My point was that the summary of this article was so incomplete and full of spin that it looked like a political advertisement.
Foreign object debris seems to be common... (Score:5, Interesting)
At least one of the recent Soyuz failures was put down to a similar issue - debris left in a fuel line by a worker.
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In soviet russia, rag washes out you!
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Then, three years later, it was the Atlas program’s turn again. On March 25, 1993, an Atlas 1 lifted off from SLC-36B at Cape Canaveral AFS, carrying the first of the US Navy’s new UHF Follow-On communication satellites. The launch proved to an inauspicious start to the new program.
A mere 22 seconds after liftoff the vehicle’s sustainer engine began to lose thrust, ultimately reaching only 65% of its nominal thrust level at T+103 sec. The Centaur second stage performed normally, but was inadequate to the task of making up for the low performance of the sustainer. The payload ended up in an orbit far below the desired geosynchronous transfer orbit. The spacecraft used its own onboard propulsion system to climb to a higher orbit, but one that still proved to be too low to meet mission requirements.
Analysis showed that the sustainer thrust decay was due to a simple problem. The Atlas sustainer engine thrust level was controlled by a regulator that was adjusted by turning a screw. A set screw was to be tightened to ensure that the adjustment screw did not move due to in-flight vibration, and that had not been done properly. The result was another fatal Oops!
The result of a GAO audit? (Score:3)
So, somebody can't come up with the used rag disposal accounting paperwork and the GAO concludes that it must have been left inside?
I mean, this kind of thing is good for sponges during surgery, why not satellite assembly?
Send up some Midol? (Score:5, Funny)
So, the problem is the satellite is 'on the rag'?
Speculation, not fact. (Score:5, Insightful)
So no, we don't know that a dirty rag caused a two billion dollar satellite to fail. We think a fuel line became clogged, and some government bean-counter pulled the dirty-rag hypothesis straight out of their derriere so they could sign off on this one and go home.
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FTA: "They didn’t know it at the time, but a fuel line had become clogged. The blockage “was most likely caused by a small piece of cloth inadvertently left in the line during the manufacturing process,” according to the Government Accountability Office." (bolding mine). So no, we don't know that a dirty rag caused a two billion dollar satellite to fail. We think a fuel line became clogged, and some government bean-counter pulled the dirty-rag hypothesis straight out of their derriere so they could sign off on this one and go home.
The GAO was probably basing its conclusion on statements from Lockheed itself. According to this [bloomberg.com] it was Lockheed that concluded the problem was some cleaning material left in the line.
"It should not have happened,” Deputy Under Secretary of the Air Force for Space Programs Richard McKinney said. “It was a quality mistake and we took steps to make sure it does not happen again,” he said. “It was obviously a very serious error.”
“It appears that there was a blockage in one of the fuel lines,” McKinney said. Lockheed thinks “it was caused by some cleaning material that was used in a line that was not properly vacated when they went through production.”
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Please describe to me the process by which you would prove that a fuel line currently in geostationary orbit 24,000 miles above the surface of the Earth has a dirty rag (specifically - As opposed to a dead mouse or a styrofoam peanut, for example) blocking it, without taking it apart and finding said rag.
Yeah, thought so, "dipshit".
Heading hyperbole (Score:5, Informative)
Glad they didn't go to a backup! (Score:5, Insightful)
"Finally, it speaks to the size and age of the U.S. space arsenal that the Air Force felt it had no choice but to rescue AEHF-1 instead of replace it with a back-up spacecraft. 'The asset inventory is getting so tight that they spent months limping the heap to its proper orbit,' the insider lamented."
Look guys, before you throw away (replace with a backup) a $2 Billion satellite, I damn well hope you try some pretty heroic measures. Those are my tax dollars in (the wrong) orbit! So I'm very glad you didn't have (to use) a backup satellite.
Anyway, does anyone know if the low power thrusters which were eventually used to put this satellite into the correct orbit used the same fuel tank as the clogged thruster? Otherwise 1) I'm very surprised they had enough fuel to get there and 2) they would probably have very little left to last the lifetime of the mission. So let's hope that all the thrusters used a central (hydrazine?) fuel tank and there's plenty left.
Space is hard and while the U.S. program has certainly had its ups and downs at least it hasn't seen the near total collapse as what happened to the Ruskies. They had quite a bad year last year and that blogger walking around their factory just exposed their problems more. If Mars is going to be a "Red" planet it will because of China not Russia.
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Where did you get this info? Typically hall effect thrusters don't run on hydrazine..
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Ok.. It appears that they used both. I should have read the whole article..
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According to this:
http://spaceflightnow.com/atlas/av019/111009.html [spaceflightnow.com]
They used the hall effect thrusters instead of the hydrazine/nitrogen tetraoxide engine. The hall effect thrusters run on xenon and electricity, so NO they did not use the same fuel source. The hall effect thrusters have a specific impulse of ~8000s instead of the ~300s for hydrazine, so they are insanely fuel efficient, but extremely low thrust. (1/4N vs ~450N for the main engine)..
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Ok.. It appears that they used both. I should have read the whole article.. The hydrazine was expended in a 5N thruster over 12 firings (raising the satelite about 1/7 of the way and changing the inclination), then the 0.25N hall effect thrusters were used for the remaning 19400miles (firing 12hours a day for 8 months)..
RAG?? (Score:2, Informative)
A Dirty Rag? C'mon - RTFA! "The blockage 'was most likely caused by a small piece of cloth inadvertently left in the line during the manufacturing process,' according to the Government Accountability Office."
That could mean a tiny fragment of fabric. It's not like they put a rag in the gas tank to keep gas from leaking out. sheesh.
Remaining maneuvering fuel depleted? (Score:2)
One info I have yet to see in any of the stories I have read on this.
The "main" engine doesn't start so they use thousands of firings of the maneuvering thrusters to circularize the orbit. Do the "main" & maneuvering thrusters use the same fuel source or has the mission longevity been compromised? Does anyone know?
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How do they know it was a rag in a fuel line? (Score:2)
Crap article with crap sources (Score:2)
Translation:
We spent tens, perhaps hundreds of thousands, heck maybe even a couple million on labor to save a $2,000,000,000 dollar satellite rather than build another 2 billion dollar sate
Weaponize it (Score:3)
We must be increasingly on the alert to prevent our enemies from taking over our satellite fuel lines, thus knocking out our military communications. Mr. President, we must not allow a dirty rag gap!
One would think (Score:3)
aliens (Score:3)
Bottle in the car (Score:3)
Reminds me about all those stories of bottles put inside cars during assembly. Here's a funny one (albeit fictional):
A man goes to a car dealership one day after inheriting a good deal of money (or after a great business deal, whatever -- he has a lot of money somehow). After looking around the lot, he picks out the nicest, newest, fanciest, most expensive car he can. He pays cash up front and drives out of the dealership in the new car.
On his way home, he starts hearing a rattling sound -- something must be wrong. So he turns around and goes right back to the dealer. The dealer is of course very sorry, and offers to either fix the car or let the man take a different one while they order a replacement. The man really wants the car, so he just has the guy fix it. Two hours later, the mechanics give the car back, saying they couldn't find a thing wrong with it. The man is a bit wary, but he drives home. Whatever the rattle is, it has stopped.
A day or so later, the rattle starts again. He takes it to the dealership, and they still can't find anything wrong with it. This continues for a number of weeks -- sometimes the rattle even goes away on its own. Anyway, after nearly two months of it, the dealer is very upset -- he doesn't want to get a bad reputation. So he orders a replacement and exchanges it with the man for the malfunctional car.
Then he orders the mechanics in the shop to do a complete tear-down to figure out the problem. They begin taking the car apart, piece by piece, but they can't find anything -- until they take apart the door. Inside, they find a piece of metal pipe, along with a note. Written on the note, in a scrawling, worker's hand is: "So, you finally found the rattle, you rich son-of-a-bitch."
Re: (Score:2)
and has destroyed vital military property
time to lock him up with no trial and throw away the key
Nah. NASA has now invested $2 Billion into the education of this unfortunate soul. He'd better stay and do his best to make up for it :-P
Re: (Score:2)
There is no possible way that this fellow's mistake was the only one made during the entire production process. There were thousands of mistakes similar to this that went into the satellite in question (there are thousands upon thousands of parts and processes required, after all), this was merely the one that escaped all efforts to eliminate it... Unless you can prove that he really was conspiring to sabotage the satellite, you need to blame the process and not the producer. For all we know, the rag ha
CHECKLIST (Score:4, Informative)
The airlines did it and improved by amazing amounts (nobody remembers how bad it was) and the things were much less complex to fly back in those days; the pilots were insulted by it as well. CHECKLISTS WORK.
Something that important should involve multiple checklists; to error is human no matter how good and smart you are. Doctors are the most arrogant pricks I've ever met so they'll put up a huge fight and have a hard time admitting it when the error rate goes down by half. It likely would go down by half; that is how badly it is needed.
Nurses too... a friend of mine fought off his nurse violently (as much as he had strength post op) she had to call people in to hold him down and sedate him and luckily somebody heard his screams and READ the chart and realized she had the wrong person! he would have died and without a proper autopsy the cause wouldn't have been known. Mistakes killed my father too. Checklists must be mandatory by law like the pilots who have no issue with them today.