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Minor Damage Found On Space Shuttle
The BBC is reporting on minor damage to the space shuttle Atlantis revealed by a 10-hour inspection in orbit. On the shuttle's right side, near where the wing joins the body, inspection revealed a 21" (53cm) line of chips in the tiles that make up the vehicle's heat shield. "...more analysis by engineers would determine whether a 'focused inspection' was needed in that specific area. If so, astronauts would use sensors to determine the exact depth of the damage to the heat shield tiles. NASA has placed the space shuttle Endeavour on stand-by to rescue the crew of Atlantis if they are endangered." The crew couldn't shelter on the ISS in case of trouble, because their orbit is higher and on a different inclination.
.. if they launch Endeavour to rescue Atlantis, and Endeavour suffers damage at launch?
Roger that.
FWIW, you can get a lot of mission info while it happens, even if you don't have satellite TV - http://www.nasa.gov/multimedia/nasatv/index.html
Pathological kinda promises Path + Logical - but instead, you get stuck with pathetic.
i guess it's not just dropping to another altitude. it's about changing the orbital plane, for which they don't have enough fuel.
More info here: http://spaceflightnow.com/shuttle/sts125/090512fd2/index5.html
"And Scooter, also I've got some good news about the tile damage that we saw on the starboard chine area earlier today," astronaut Alan Poindexter radioed from mission control shortly after 8 p.m.
"Oh, I'm looking forward to that. Go ahead," replied shuttle commander Scott "Scooter" Altman.
"It turns out that a focussed inspection of that area on the starboard chine is not going to be required," Poindexter reported.
"All right, you've got some happy EVA campers on that," Altman said.
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So what makes you such an expert?
Nasa experts have looked into all of these issues and potential solutions.
A mere couple of hundred miles is not a problem (you do know how fast the shuttle flies don't you?) Orbital mechanics is the problem. The fuel required for the shuttle to change orbits would weigh too much for it to get off the ground in the first place.
The risks have been very carefully considered, with the mission ruled out of safety grounds for a long time. Yes, they are pushing the risks on this mission but having a back up shuttle on the pad ready to lift off in three days (you do know about this don't you?) mitigates some of the risks. That together with other changes they have made have kept the risks of a catastrophic failure below the limit set for every mission.
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I read some article that said it was the latter -- putting it into a suicide path into the ocean.
See this AP article:
Is this really a new development that the Shuttle gets increasingly fragile or is it just the fact that since Columbia it gets checked extra carefully and therefore revealing what before just went unnoticed?
Don't know much about orbital mechanics, do you?
Changing Apollo 13's course from what it was originally to a free-return course requires the merest nudge compared with the fuel required to change orbital planes like what would be required here.
Also, consider that the LEM had enough fuel in its descent engine to slow its descent and keep from smashing into the moon and an ascent engine to get it back up (though I don't know if the ascent engine fuel is usable by the descent engine).
"Have Rockets Run Their Course?"
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
The descent engine and ascent engine were entirely separate, since the entire descent stage of the LM was discarded on the moon for return. There were no interconnections between the two. That does not mean they couldn't have burned the DPS to exhaustion, staged, and then burned the APS for as long as required.
In any event, the shuttle cannot carry enough fuel to make the orbit change required in this instance simply because the tanks aren't big enough. You can't put 500 gallons of gas in a tank that only holds 300. This is not a simple matter of flying in a line from point A to point B. Go download Orbiter and educate yourself.
I think the best solution would be if Atlantis could be brought back by autopilot. If the damage is marginal (that is they THINK it might destroy the shuttle but are not sure) then bringing it back unmanned would give you the possibility (if the damage is survivable) of recouping your billion dollar plus investment.
Won't work. The landing spots are generally near the takeoff spots. The takeoff spots were located so if it blows up on takeoff, the parts rain down on the dolphins and whales. Unfortunately (?) when it comes in to land, it arrives from the opposite direction, and no one selected landing sites that are empty to the west. Unfortunately gets a ? mark because back in the 70s when the shuttle was going to do everything for everyone, everywhere, it was occasionally claimed it would be able to land on commercial runways... so if you're coming in a bit short, just land at colorado international airport. That, along with most of the vehicles abilities, was all cut during development to save money.
The astronauts may have lobbied to keep NASA from giving the shuttles the ability to land themselves (or via ground control) in an attempt to keep pilots from being made irrelevant. (Throwback to test-pilot days I guess).
Based on the faulty assumption that all pilots do is keep it straight and level and wait as patiently as the plane lands. The whole point of decades of training for airline pilots and astronauts is for them to fully understand each little bit of the A/C and how to work when it breaks. They know their vehicle like a kernel hacker knows his kernel.
So, say the exhaust temperature of one APU is fluctuating. If the computer could "do something" to fix it, it would. The humans job is to invent new ideas of troubleshooting and fixing. Flip that switch see what happens, try this maneuver. The stuff the Apollo 13 guys did is not amazing or unlikely or lucky, despite what the general public thinks, it is in fact exactly what they were supposed to do...
Think of that Canadian pilot whom invented a way to put a jetliner in a slip to lose altitude to land at an abandoned military field when the plane ran out of gas because of metric/imperial issues.
Thats why you have humans onsite, in the loop.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Thanks for that, Mr $0.02, that made me smile :-)
Daveime, no I'm not an expert but I do understand the laws of physics and have read up on this. Some of what you say is correct, but a lot isn't.
A small amount of fuel could be used to get the shuttle to visit the ISS. Unfortunately, this would be in a very elliptical orbit so they would only be able to (very) briefly wave through the window as they flew past each other at a very large differential speed before ploughing into the Earth in an unfortunately bright fireball.
To get to the same altitude as the ISS (keeping the orbit circular) requires dropping by 210km and speeding up by 200m/s. Not in itself a great requirement on fuel. The problem is that the orbit inclinations are so different (HST is 28.5 degrees, ISS is 51.6 degrees). To make this change requires something like a 3000m/s speed change sideways (this calc is only order of magnitude accurate). This requires a lot of fuel.
As others have stated, the current design of the shuttle has some major faults. Not being on the top of the rocket being one of them. This is not news and has been known for a long time and yes it has been taken into account in the next design (which isn't a shuttle at all).
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http://spaceflightnow.com/shuttle/sts125/090508sts400/
"When we made the decision, the odds were 1-in-473 that we would have a problem on the shuttle for which a rescue shuttle was the solution," Griffin said. "Now, there are a lot of problems you can have on the shuttle, right? There are a lot of ways you can die on the shuttle, which is what gives you the overall shuttle PRA (probabilistic risk assessment) of about 1-in-75 or so. So you're roughly five-and-a-half, six times likelier to die on the shuttle for some reason that the backup shuttle can't save you from than you are to die from one the backup shuttle can save you from. ... From a statistical point of view, it makes no real sense to have a backup shuttle.
"However, here's the flip side. ... Those numbers cannot be explained to politicians or the general public. And should we have a failure with those 1-in-473 or whatever odds it was, should we have a failure that the rescue shuttle could have saved you from and we had not done it, the consequence to NASA would have been incalculable. We would appear to have been cavalier with human life, we would appear to have not taken every possible precaution, we would appear to have been coldly calculating the odds and rolling the dice with people's lives. And the appearance of behaving that way, in my judgment, was unacceptable. I could not risk that for NASA."
While the overall risk of impact damage is about three times higher for a Hubble mission than a flight to the International Space Station, it is not as bad as flight planners initially feared.
"We know we're accepting a little higher risk for this flight," Steve Stich, manager of the orbiter project office at the Johnson Space Center, said in an interview. "That's why we've tracked it very carefully."
Even factoring in debris from a satellite collision in February between a defunct Russian Cosmos satellite and an Iridium telephone relay station, the mean odds of a catastrophic impact during the Hubble mission are on the order of 1-in-229, which is well below the 1-in-200 threshold that requires an executive-level decision by NASA's leadership.
A preliminary analysis put the odds at 1-in-185, but the numbers improved after recent radar observations and consideration of the shuttle's orientation in space during the Hubble mission. The planned orientation, or attitude timeline, reduces the crew's exposure to impacts that could damage critical areas of the ship's heat shield, the coolant loops in the shuttle's cargo bay door radiators and cockpit windows.
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