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Shuttles Grounded Once Again
PipianJ writes "After discovering that the piece of the shuttle that fell off mysteriously, not actually striking it, (as reported earlier) was a piece of foam insulation not unlike the piece that ended up in the destruction of Columbia, Yahoo News reports that NASA has once again grounded the shuttle fleet."
The point is, now that we're looking intensely for problems in this area, we're going to find them. We're looking with eyes, cameras, satellites, lasers, sensors, robotic arms - all with unprecedented scrutiny. What do we expect to find? The shuttles are the most complicated pieces of machinery ever built, designed to launch into space with a controlled explosion, and then return to earth. Regardless of whether some here think the shuttle is junk, whether it's unnecessary, whether Air Force jocks doomed the program for the beginning, whether manned spaceflight is sentimental tripe, etc., the fact remains that flying something like the shuttle is a risky endeavor.
It's all about smart management of risk. Eliminating risk, especially for something like the shuttle, is impossible. This focus on debris falling from the shuttle is nothing more than a reactionary CYA tactic in the midst of a media circus in case something else like this were to happen again. Doing get me wrong: it's wise to consider the problem, to attempt to prevent it, and to ensure there is not undue exposure. But that exposure cannot be eliminated, and this intense focus on debris in particular beyond anything else, even in light of Columbia, is unwarranted.
NASA is operating in panic mode: one more catastrophic shuttle failure, and that's the end of the shuttle program, and essentially the practical end of the ISS and a lot of scientific research to boot. If you're paralyzed with fear, you're, well...paralyzed.
This New York Times article, which I posted in the previous article on this, sums up the situation quite nicely, for those who may have missed it.
Notable:
"How do you distinguish - discriminate - between damage which is critical and damage which is inconsequential?" asked Dr. David Wolf, an astronaut who spent four months aboard the Russian space station Mir. "We could be faced with very difficult decisions, in part because of all this additional information that we will be presented with."
"...the harder they look, they'll find more things."
"There is risk in anything you do."
July 27, 2005
Intense Hunt for Signs of Damage Could Raise Problems of Its Own
By JOHN SCHWARTZ
CAPE CANAVERAL, Fla., July 26 - Now that the Discovery is in orbit, the examination begins. Its 12½-day mission will be the most photographed in the history of the shuttle program, with all eyes on the craft to see if it suffered the kind of damage from blastoff debris that brought down the Columbia in February 2003.
There were cameras on the launching pad, cameras aloft on planes monitoring the ascent, cameras on the shuttle checking for missing foam on the external fuel tank, and a camera on the tank itself. One camera caught a mysterious object falling from the shuttle at liftoff; radar detected another, about two minutes into the flight. Cameras aboard the shuttle and the International Space Station will monitor the Discovery until the end of its mission.
But all this inspection may be a mixed blessing. The more NASA looks for damage, engineers an
I guess you've never heard of an embedded system.
Those can't ship with bugs. Try applying a patch to several hundred 512 byte micros that are controlling the charging systems on the shock paddles in hospitals.
---
ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
Nice idea, but it won't work. Ice formation on the tank has nothing to do with it. The trouble with hand-laid foam insulation(which is what this was) is that large air pockets can form during the forming process. These air pockets are at atmospheric pressure (14.7 psi). As the craft climbs higher into the atmosphere, the surrounding air pressure drops, causing that pocket to expand. Eventually the pocket can pop like a balloon, knocking off a chunk of foam. Were the tank painted, the paint would just come off along with the rest of the piece.
so, Thom Patterson - CNN reported last night that it was a 1.5" piece of tile. MARCIA DUNN, AP Aerospace Writer - on the yahoo! news - says that it's a "sizable chunk of foam insulation -- the very thing that doomed Columbia" - but then later says that it was indeed a 1.5" piece of tile while in the latest report from yahoo! it's simply "a large piece of foam insulation broke." interesting to see this evolve. at least it's not being sensationalized...
Not really.
The X-33 was over-budget, late, and suffering major development problems. The performance was getting worse and worse. And then you would have had to hope that Lockheed-Martin was willing to put up their portion of the funds to build the production booster.....
And, at the same time, Iridium was bankrupt, "Dark Fiber" was eating into comsat requirements, etc.
And worst of all the Skunk Works had said, "Hey, we've been building all kinds of classified stuff all these years. I know that nobody in the public field can make a multi-lobed composite hydrogen tank, but we can pull one off, winkwinknudgenudge" So when it was shown that they couldn't, people lost faith. Especially because the only actually novel, testable parts of it was that multi-lobed composite hydrogen tank and the linear aerospike... everything else wasn't going to be getting a proper workout because it wasn't going to have enough speed to really properly test the metal skinned TPS or much else.
The problem was the X-33 was the riskiest design of the three contenders. So it was mostly doomed from the start....
No, they'll probably figure out how to dust off the shuttle yet again and fly it. Remember, it's just the PAL ramp that's the problem, so they might just be able to change it to using a metal cover.
Gentoo Sucks
I'm going to treat this as if you were serious...
Liquid hydrogen (the stuff in the big, brown tank, along with liquid oxygen) has a boiling temperature of about -434 degrees fahrenheit.
The launch site is next to the ocean and bounded by swamps and rivers. Humidity at the launch site is quite high. The surface of the external tank, if exposed to the atmosphere without the foam, would develop a very thick layer of ice - a material with considerably higher density than foam.
Now, which would you rather flake off of your orbiter during climbout: ice, or foam?
The foam in question insulates the disposable fuel tank so ice doesn't form on it. It does not reach orbit and is not part of the shuttle. The problem with the previous shuttle was that the foam hit the shuttle tiles as it fell off. Since this foam did not hit the shuttle, there is no problem with it.
Infuriate left and right
Northrop Grumman and Boeing are getting prepped for the CEV, the successor to the space shuttle. According to this page, they are expecting flight demos in 2008 and manned CEV flight by 2014. If Griffin (the new NASA administrator) has his way, this will be fast-tracked to 2010. Exciting times are ahead...
Slashdot's first reaction to VMware
How about switching back to the older foam that shead less. NASA switched to an "envrionmentally friendly" foam a few years back, even though they have an exemption...
-- 73 de KG2V For the Children - RKBA! "You are what you do when it counts" - the Masso
Astronauts are on government pay scales GS-11 thru GS-14.
The lowest step of GS-11 is $45K per year, the highest step of GS-14 is $99K per year.
Another way to look at it is that they do it in spite of the middling bucks, because that's the sort of person they are.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
Considering it's been 360 years since the last English Civil war and 140 years since the last American Civil war, I'd be inclined to say that the American system is fairly stable, but doesn't look set to be breaking any records quite yet. I come from Australia where the last thing that looked like it could have become a civil war (but didn't) happend in Ballarat 160 years ago and so even that beats America's current record.
When Argumentum ad Hominem falls short, try Argumentum ad Matrem
>You're limited in how much and what size by doing that. In case you all haven't noticed. The orbiter plus the solid rocket boosters form a powered triangle. A more stable formation for carrying a big load, say a telescope.
You're kidding, right, AC? The Shuttles can carry at most 28 tons of cargo. Saturn V could lob 118 into LEO. Proton can boost almost as much as Shuttle, for far less money, including a series of integrated space station components (Zarya, Zvezda, Mir baseblock). Maybe the trunnion pins were great for launching Hubble, but that is the exception. Your "triangle" thing doesn't make sense, inline thrust structure is more efficient, less mechanically complex and makes trajectory calculation simpler.
>And siting on top of a roman candle is safe?
Yes, comparatively. For manned flight, a rocket under the crew is far safer than having components next to them. Launch escape towers are safe, accurate tools for keeping crews safe from an exploding "candle". There is footage online of a Soyuz capsule popping off the rocket right above the pad, the rocket failed but the crew lived. The same can't be said for low-altitude launch problems with Shuttle.
Capsules, rockets and tugs for station components make sense. Buck Rogers spaceplanes don't.
gigantino.tv - Heavy but weighs nothing.
The facts of the crash are not as cut and dried as either of you state and many are wrong. The pilot survived, along with most of the people on board, and was found guilty of manslaughter in the 3 fatalities connected to the crash. The funny thing is that two primary claims of the pilot in his defence were Operational Engineering Bulletins from Airbus Industrie regarding:
OEB 19/1 Engine Acceleration Deficiency at Low Altitude
OEB 06/2 Barometric Cross Setting Check
In a nutshell, the bulletins state that the engines didn't respond "normally" to throttle input and that barometric altitude indicator did not comply with airworthiness regulations. Air France chose not to share this information with the pilots. Naturally, this is the kind of thing that the data recorders could shine some light on. The data supported the claims that it was pilot error and the case was closed.
In 1998 it was determined that the data that was supposedly from the flight had been compromised. The flight data and cockpit voice recorders had been tampered with during a 10 day period when they were not in the hands of the magistrate's office. They were in the hands of the French Civil Aviation Authority (DGAC), contrary to their own regulations. The funniest thing is that one of the boxes presented as coming from the crashed A320 spontaneously changed its markings during the interim. An independent body from Switzerland determined that there had been a switch by comparing photos of the CVR being recovered from the crash site with the one presented as evidence.
While the "official" verdict was pilot error there is enough evidence to call that verdict into question. Who lost the least with the verdict? Airbus was introducing an advanced aircraft and attempting to challenge Boeing, and they were selling the "advanced" electronics of the 320 series: even admitting that there may be an issue with the system would have had devastating consequences.
The onboard computers did lead to a few incidents with the A320. In 93 a Lufthansa pilot made a landing with a very low sink rate, so low the flight computers would not allow the deployment of thrust reversers or brakes for a number of seconds. The plane ended up going off the runway. I guess you could make too soft a landing.
Admittedly they seem to have solved those problems, and I have no qualms flying in an Airbus but then again I flew Aeroflot a couple of times.