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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.'"
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.
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?
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/
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