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.'"
Re:Lockheed gonna get sued? (Score:5, Informative)
Heading hyperbole (Score:5, Informative)
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.
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: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.
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."
Re:The answer appears to be a yes. (Score:3, Informative)
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: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.
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
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.
Re:Lockheed gonna get sued? (Score:3, Informative)
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: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.
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.