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Debris Seen Falling Off Shuttle During Launch
kushboy writes "According to an article on CNN.com, there is video of debris falling off Discovery during its launch earlier today. While the debris does not appear to hit the shuttle, extra precaution and more video will be analyzed due to the Columbia mission of 2003. 'NASA has taken steps to minimize the amount and size of debris falling off the shuttle's exterior tank during its ascent. But the space agency has said it's impossible to eliminate falling launch debris.'"
http://www.spaceflightnow.com/shuttle/sts114/05072 6images/
NASA officials said an object that may have been a 1 1/2-inch piece of thermal tile appeared to break off from the Discovery's belly during liftoff. It came off from around a particularly vulnerable spot, near the doors to the compartment containing the nose landing gear.
http://www.foxnews.com/story/0,2933,163629,00.html
"Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
Well, there is photographic evidence of one tile fracturing and breaking off. So aybe debris did infact hit the shuttle.
2 6images/
Images here:
http://www.spaceflightnow.com/shuttle/sts114/0507
In the early design phases of the shuttle, the designers decided to go with solid fuel rather than liquid fuel to help keep the costs down. It seems to me in retrospect that if we'd launched both Challenger and Columbia on top of their boosters rather than strapped to the side then we'd still have a full complement of shuttles, saved a whole ton of money, and been four years further down the road than we are today. The Saturn/Apollo stack was exceptionally robust, and its a shame we abandoned them so quickly.
If you don't want crime to pay, let the government run it.
The hottest parts of the Orbiter on reentry are the leadng edges and the nose, with the underside cooler as you work aft.
That's why Columbia was doomed when the Reinforced Carbon-Carbon leading edge was damaged and the hottest gases that could enter the Orbiter melted the wing supports.
Columbia and every single Orbiter after her has lost tiles or had mild to signficant damage on every single flight. This is not inherently serious. Losing a lot of tiles in hotter areas or significant damage in one crucial area is cause for worry.
Nowandays Orbiters don't use much in the way of tiles at the top of the vehicle, preferring to use thermal blankets. Only a serious breech of the nose or wing edge RCC is dangerous in the extreme. Tile damage elsewhere is nothing to sneeze at, but generally the underside tile loss is not as bad because the heating and the air movement is less direct.
Vos teneo officium eram periculosus ut vos recipero is.
The damage is close to the upper limit of what they could repair in space, if it does prove to be tile shear. This may force a rescue mission.
Furthermore, we won't know until at least day 3 of the mission, according to the BBC, as to whether the damage is significant. We won't know tomorrow, from the sounds of it, and depending on the nature of the damage we might not know until much later, as they may need to run computer simulations to determine the likely damage to the heat shielding, if the damage is not something they can visually inspect.
The bird strike to the external fuel tank had no significant impact (pun intended) and the debris from that doesn't seem to have caused any problems.
There are two worst-case scenarios, at this point in time. First, the tile may be sheared and the damage not repairable with the repair kits they have. Of the worst-case scenarios, this is the most likely, although it is still considered improbable. This would force a rescue mission and possibly the cancellation of all remaining shuttle flights, as it would be too big a political risk.
Alternatively, the damage may have been caused from something coming loose on the INSIDE of the landing gear assembly. An impact from the inside might easily knock the black outer layer off but not cause noticable damage to the tile. The odds of this are extremely low, but certainly not zero. It is also unlikely the astronauts will check for internal damage for the front landing gear, which means that if this IS the case, the shuttle will crash hard on landing and be destroyed.
Debris is inevitable, this is perfectly true. This is why such systems SHOULD have the best monitoring that money can buy, including internal sensors that can detect anomolous conditions.
In the case of Columbia, the damaged sections would have cooled faster than normal, due to being open to space, and would have had far higher radiation levels than normal - again from being open to space. From data like that, it would have taken all of 30 seconds to figure out the damage was significant and potentially catastrophic, with or without photographs.
Frankly, I don't know why NASA is so obsessed with photographs, as they clearly aren't telling NASA whether the damage is significant or not. Internal monitoring is needed to establish something like that, especially for components that can't clearly be seen by some far-away camera due to angle or obscuring fuel tanks.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Well, if they want to keep their traffic up and keep people from moving over to Digg maybe they should think about actually doing their damned jobs sometime. If this was a non-profit site or something I could understand the slack, but they're making money here and they need to step things up.
Honestly, I'm getting pretty sick of slashdot lately. I'm finding a lot more interesting articles over at digg. The only thing missing is the witty satire of the slashdot crowd.
VSE: Visual Surveillance of Extremities...it's a term from the Thomas Covenant: The Unbeliever series. Thomas, suffering from leprosy, needed to constantly check his body for signs of damage, as he was unable to feel pain from injuries. I thought the term was especially appropriate for the current situation with the Shuttle, as a visual inspection will have to be performed to identify potentially life-threatening damage.
____
~ |rip/\/\aster /\/\onkey
We're talking about several things here. First, the bird that was hit by the EFT (oh well). Second (and is this what everyone's fussing about?) two vent covers on the dorsal section of the shuttle were covered with pieces of Tyvek material (same people that make the waterproofing wrap for houses). Those fabric covers were designed to fall off as soon as the craft started moving. During today's briefing, NASA indicated, IIRC, that the two covers even had small parachutes to let them down slowly. The briefer said that these two bright-colored objects were clearly seen doing just what they were supposed to do: sliding down during the first moment of the launch.
Completely unrelated would be the hunk of whatever it was that sloughed off of the EFT just before separation, but which would have not struck the orbiter. Also unrelated was the apparent sheering off of a small, perhaps 2-3 inch chunk of a tile near the nose gear cover (just aft). They may deploy the arm to check that one out, but the tiles get pitted all the time.
Don't disappoint your bird dog. Go to the range.
There is NOTHING else ever designed or built than can safely return an object from space the size of a school bus
Except, you know, the Russian Buran Shuttle with 20 tons return capacity vs the shuttle's 15 - and 30 tons of launch cargo capacity vs the Shuttle's 25. Best of all, the Buran could fly to orbit and back on autopilot without a human crew if needed (as it successfully did on a test flight). The best thing that NASA could have done at the time to replace their shuttle fleet would have been to fund or buy Buran from the Russians when they ran out of money. the Russians built an amazing robot spaceplane in the 80's, something that NASA still has not achieved.
But don't let silly things like, oh, facts get in the way of all your flag-waving.
NASA's shuttle is a bastard design created from political compromise: the military wanted it, the scientists wanted it, the politicians wanted it. As a result it works for almost nobody and is a 30-year old deathtrap. I'm suprised the loss rate has been so low - I have no idea what drugs NASA is ingesting, I'll be very suprised if this one isn't lost as well. The shuttle should be killed and replaced ASAP, preferably taking some serious clues from bulletproof no-compromise brute simplicity Russian space engineering - which is currently the best in the history of the world (until the Chinese or commercial sector catches up and passes them).
A simple example:
If the shuttle's re-entry angle is wrong, EVEN WITH NO DAMAGE, airframe stress becomes critical, it breaks up and everybody dies.
If a Russian space capsule's re-entry angle is wrong, they experience slightly higher G-forces and the pickup helicopter takes a couple of minutes longer to reach them after parachuting to earth.
A fact to ponder:
Modern metal alloys are tough enough to survive re-entry without protection from heat tiles. Get that? In a modern design, NO HEAT TILES ARE NEEDED. Which completely eliminates the cause of one shuttle disaster (when the heat tiles failed).
So why are we sticking with the old Shuttle?
You mean like the alternate design with stages that used the Saturn F-1 engine? http://www.nasm.si.edu/exhibitions/gal114/SpaceRac e/sec500/sec542.htm
has photos and descriptions of the preliminary designs.
Seems like the CEV will likely be top-mounted rather than side-mounted. http://en.wikipedia.org/wiki/Crew_Exploration_Vehi cle
(Please, no side-talking jokes.)
Despite your knee-jerk Slashdot groupthink response, Fox News can does report news objectively. You are only responding this way because it's Fox. The story itself was not written by Fox, only posted by them. Fox got it off the AP wire, just like EVERY OTHER FUCKING NEWS ORGANIZATION that posted it. God you're an idiot.
"I have never won a debate with an ignorant person." -Ali ibn Abi Talib
http://msnbc.com/modules/spaceshuttle/discoverylau nch/
There may certainly have been "Debris Seen Hitting Shuttle During Launch".. But this should be no surprise since NASA scientists and engineers have stated that debris always falls, and it is 'impossible' to prevent. That's why, should you look at the shuttle time line, you will see that they are taking many more preventative measures than have ever been taken in the past. However, this begs the question.. Why weren't these steps taken before?
26 Jul - Takeoff - Wednesday - A large amount of camera and recording equipment are used to monitor the body of the aircraft during liftoff.
27 Jul - A 100 Foot Robotic Arm will inspect the shuttle's shield areas.
28 Jul - The shuttle will backflip approx 600 feet from the space station, allowing it's underside to be photographed with high-resolution cameras on the space station.
29 Jul - 3 Aug - Three 6.5 hour spacewalks have been scheduled to test and repair any heat shield damage.
Source: http://www.nasa.gov/
I could be wrong but as i remember from space camp the shuttle regularly loses a couple of these tiles. Granted, I am going off an 8 year old memory so someone please correct me if i'm smoking crack.
The shuttle program has lived with damage from debris from the very first flight, in 1981; in 113 missions the orbiters have been hit by debris some 15,000 times, mostly on liftoff. The National Aeronautics and Space Administration replaces about 100 insulating tiles after every flight and repairs many more than that, Stephanie S. Stilson, the vehicle manager for Discovery, said Monday.
In fact, the rest of this article sums up the situation quite nicely:
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 and other experts say, the more it will find. And the risks of overreaction to signs of damage while the shuttle is in orbit may be just as great as the risks of playing them down.
"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 shuttle program has lived with damage from debris from the very first flight, in 1981; in 113 missions the orbiters have been hit by debris some 15,000 times, mostly on liftoff. The National Aeronautics and Space Administration replaces about 100 insulating tiles after every flight and repairs many more than that, Stephanie S. Stilson, the vehicle manager for Discovery, said Monday.
Now, though, it will be far easier to spot such damage while the shuttle is still in orbit. Thanks to a $15 million laser camera system developed by a Canadian company, Neptec, for example, NASA can detect a crack of just two-hundredths of an inch, the width of two business cards pressed together. On the leading edge of the orbiter's wing, such a crack could admit dangerous amounts of superheated gas during re-entry. A similar crack elsewhere might not.
It was a large hole in the left wing's leading edge, caused by impact with a 1.67-pound piece of insulating foam during the launching, that led to the Columbia disaster.
But if a crack is detected, said Iain Christie, director of research and development for Neptec, "how is NASA supposed to explain that this is not a problem?"
Nor is it clear how it could be fixed. NASA's efforts to create a repair kit for tile and leading-edge panels, a recommendation of the board that investigated the Columbia accident, have not been successful. Techniques will be tested during a spacewalk in coming days, but they are not ready for an actual repair, and the Discovery astronauts have said they would not want to trust any patchwork on a return to Earth.
Another option, the "safe haven" plan, would involve abandoning the $2 billion shuttle and having the astronauts wait in the space station for a rescue mission. For that to work, another shuttle would have to be launched within a few weeks.
That is theoretically possible but carries risks of its own: the chance, for example, that the orbiting astronauts would run o
Cargo gets returned on every flight. For example, here are the most recent missions which had significant items that you just can't let burn up.
STS-114: MPLM, only have two of these, have been used several times by the shuttle.
STS-107: SPACEHAB, science module for the Columbia cargo bay.
STS-111: MPLM
STS-108: MPLM
STS-105: MPLM
STS-100: MPLM
STS-102: MPLM
STS-106: SPACEHAB
STS-99: SRTM
STS-96: SPACEHAB
That right there is 10 out of the last 21 flights in 6 years where a major item has been returned (and flown again) on a shuttle, except of course for the SPACEHAB lost on STS-107.
This doesn't even include the robot arm which is housed in the cargo bay. We wouldn't be able to build the ISS without the shuttle arm.
The shuttle docking ring and airlock are also in the cargo bay. Very hard to do anything, like fix Hubble, let alone build a station, without an airlock.
Don't throw away that very huge cargo bay too fast.
Sorry, but after some investigation, I think you are the troll here. Hell, you tell us to search for your email address in NASA projects and you don't even post your email address, not even in your profile!
As it may be, I happen to have a few friends at NASA as well, as my engineering school tends to send them down on co-op at a frequent rate of about one or two per year (I'm at a small engineering school, University of Louisville's Speed program). So, knowing the same things you know, I can honestly tell you that you're barking up a tree you have absolutely no evidence to support yourself on.
Measuring temperature with thermocouples? Why does it matter? We don't need to know the temperature of the undersurface of the shuttle; we've built materials in our previous studies of re-entry temperatures that are now more than capable of withstanding the temperatures, even while being mild-to-moderately damaged. What we have a problem with now is damage to the very leading surfaces of the wings, the Reenforced Carbon Carbon (RCC sections), and the scientists on the space shuttle right now are working on building a solution to those problems. We honestly can't solve this problem from earth alone; without testing the solution, we have no idea if it will work or not. And for your information, the shuttle tiles come off all the fucking time, no big deal. But to be safe, they shuttle astronauts are also testing a replacement material for the tiles, in case of a catastrophic tile event, which, just for common knowledge, has never happened.
Your temperature gradient information's about that of a college student in thermo, that's great. Thermodynamic prinipals are not that hard to understand; if a temperature gradient exists, it will correct itself at an appropriate rate. If it's too great a gradient, then yes, it could cause damage to the shuttle. But the thing is, this isn't even a question; the shuttle is a mostly depressurized space ship, and any thermal gradient created during re-entry is most likely to be a fatal event. There is nothing that the shuttle pilots can do during re-entry to stop the shuttle, and haul ass back into space and repair it, they can't bail out in an escape pod, they can't repair it while re-entering.
Every person who gets on the space shuttle knows exactly the costs of getting on it, and the payoff. Everyone knows that they can be the next person to die, even the first person to die in space. But they also know that in the history of over a hundred launches, only 2 have ever failed, and neither in space. Not only that, but more eyes are on the space shuttle than ever before, scrutinizing every last bolt, screw, manifold cover and ashtray.. okay screw the ashtray, but you see my point. It's safer than ever before, and it was never that safe to begin with. Still, the deathrate is smaller than that of car accidents in the nation, and not everyone who steps in a car realizes the dangers of the road. We take too much for granted in that way. The risks are definitely worth it though, in my opinion, as I would gladly give my life to find a new medicine to treat AIDS and cancer, to give the world well needed inventions, and to have just, for once, felt utterly weightless as I looked down at the marble of earth below.
If you had any proof at all to back up any of your claims, that'd be great, but until I see any, I can do nothing than give my blessings for the shuttle program getting back into space and bark at trolls who are being alarmist about a few, mostly planned or known about, objects falling from the shuttle. Call me back if they find out the Reenforced Carbon Carbon modules have been punctured or there's a whole the size of a basketball through a wing. Those would be reasons for alarm. But a few scraps of styrofoam-sandlike tile insulation falling from the underbelly of the shuttle doesn't scare me one bit.
"Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
The external tank has insulation on it, since it's loaded with liquid hydrogen and liquid oxygen. That insulation is prone to fall off during launch, but by that point it's really served its main purpose already by keeping condensation/ice from forming on the tank prior to launch.
Look, reentry is all about controlling the rate of energy dissipation. Anything that prolongs the reentry process and removes KE while above around 300Kft is a good thing. Right now we live with a trajectory through the atmosphere that results in low energy dissipation followed by an intense period of high heating. This is because it is a TRAJECTORY- like a falling object without a propulsion system. Shuttle improved on capsules by getting some lift out of this system but there is a LOT more that can be done. Skipping on the atmosphere can be a good thing- you pull more and more energy out before hitting the dense atmosphere below 250Kft. But this requires active propulsion, likely changes to vehicle drag area, more complex operations etc.
I was not saying that these changes are trivial- they are not. But right now there is basically NO investment being made in doing something better- and there are multiple potential paths.
BTW the MOST important thing is to reduce the downmass to what you really NEED and not what you dream about. WIth a downmass (landed) of less than 10T (5T if you can manage it)you have LOTS of options. Make it 80T and you are far more cornered.
It is wasn't even one of the ceramic tiles that caused the last shuttle to disintegrate (it didn't explode), but a reinforced carbon-carbon panel which is much larger than the tiles. Chances are that the tile poses very little if any risk, but I would certainly want the engineers at NASA to make sure this tile isn't going to be more critical than tiles lost in the past (which has happened on most missions).
As for the bird, it only hit the tank, and the shuttle isn't going all that fast only 2.5 seconds after launch.