In theory, yes you are right. A couple things to remember however:
1)SpaceShipOne was sub orbital (did not reach orbital velocities) and launching into orbit would require a couple orders of magnitude more energy/fuel.
2) Everything else being equal, a spaceplane will cost more to develop than a rocket (aluminum tubes vs a plane airframe capable of hypersonic flight). Development costs are rather significant for spacecraft as the number of units produced is very low.
When returning from the moon, a spacecraft has significant excess velocity. Entering back into an Earth orbit (like rendezvousing with the ISS) means that the CEV would need to make a burn to slow down. This would consume a significant amount of fuel (that very well could weigh as much or more than the airbags). Instead, the Apollo CM and the CEV are designed to plunge directly into the Earth's upper atmosphere, literally burning off the excess velocity through atmospheric drag. This requires a larger heat shield, but lowers the mission complexity and fuel the spacecraft needs to carry.
Re:Besides imagining a beowulf cluster of those...
on
Make Your Own Sputnik
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· Score: 2, Interesting
How many people would seriously want to do this, say launch something ~100cm^3 & 100 grams for ~10K?
If 10 people/groups would sign up, not only would they get their stuff in space, but they could help out a university team doing some of the heavy lifting
Comments? Suggestions? Reservations?
It seems that everyone forgets that the Russians had their own (almost identical) version of the Space Shuttle called Buran. The Soviets/Russians had completed or were finishing construction of 5 space capable vehicles. 1 of which actually flew into space and a second that was being readied for launch before the plug was pulled.
In the end, NASA has gotten well over 100 manned flights from its program, the Soviets/Russians only got 1 unmanned. I am not suggesting that NASA is perfect, but its Russian counterpart is not either.
Just dealing with the rocket technology:
The US held a distinct disadvantage at the beginning of the space race, which consisted of little more than placing different objects or passengers on slightly modified ICBMs. The Soviets started out with a better vehicle because their nuclear warheads were heavier. The US had developed smaller munitions and had no need for large rockets/ICMBs.
In the end, the United States was unsuccessful in building a rocket capable of sending men to the moon and the Soviet Union was not. The Saturn V had a perfect track record with 13 successful flights and no failures. The N-1 never reached even earth orbit and was canceled after 4 spectacular failures. Sounds like a pretty decisive victory to me.
NASA wants to make sure that attempting to repair the tiles is actually the best option. Up until post-Columbia, astronauts did not travel "under" the shuttle. There is a non-insignificant risk that the astronaut, robotic arm, or tools could impact the tiles and cause even more serious damage. When you factor in the inherent danger (although fairly minimal) in an EVA, add to it that there will be no visual on the space walker from the shuttle, the risks may not be worth it to fix what might be benign and superficial damage.
The folks at NASA understand the risks and they have already stated that foregoing a repair is only a risk to the shuttle that might require repairs on the ground.
Mercury*, Gemini, Apollo, and Soyuz all use(d) ablative heatshields that burn off as they reenter. The ceramic tiles (and carbon-carbon) are the most common material used in reusable heat shields like those on the shuttle (also a number of next gen spacecraft (X-Series and the Kistler K-1).
There were numerous concerns with the heatsheilds on previous spacecraft including concerns over John Glenn's Mercury flight (they kept the orbital maneuvering unit connected to the craft to hold the heatshield on) and Apollo 13, where there were concerns that the cold temperatures (the heaters were turned off after the explosion) may have cracked the heat shield.
*The first two Mercury flights were suborbital and did not require the same type of heatshield because of lower temperatures.
The U.S. has made a strong attempt to keep military and civilian space programs separate.
From the beginning, NASA was created as the civilian space program. There are undeniable technology overlaps and the US learned early on (Vanguard) that ignoring military equipment and technology was folly and would hold back the goals of the program. Except for a couple shuttle flights (which was at the same time a company could rent out a shuttle launch for their satellites), most everything has been public and decidedly civilian.
This is in stark contrast to many of the other space programs in the world. Sputnik was a part of the R-9 ICBM program, and the chinese space program was an outgrowth of the Peoples Liberation Army. And surely the US military and intelligence services have been involved in space, but they are separate. Just take a look at congressional spending, you have 3 forms of space funding: NASA (Civilian), Military, and Black. Go ahead and bash the Military and Black budgets, but please make the distinction between NASA's civilian program and the military/intelligence stuff.
The good news is that there does not seem to be anyone inhabiting space as far as we can see (and probably travel for at least thousands of years) so that is a nonissue in this case.
Slashdot Mirror
In theory, yes you are right. A couple things to remember however:
1)SpaceShipOne was sub orbital (did not reach orbital velocities) and launching into orbit would require a couple orders of magnitude more energy/fuel.
2) Everything else being equal, a spaceplane will cost more to develop than a rocket (aluminum tubes vs a plane airframe capable of hypersonic flight). Development costs are rather significant for spacecraft as the number of units produced is very low.
3) It has been tried before, rather unsuccessfully: http://en.wikipedia.org/wiki/Rockwell_X-30
When returning from the moon, a spacecraft has significant excess velocity. Entering back into an Earth orbit (like rendezvousing with the ISS) means that the CEV would need to make a burn to slow down. This would consume a significant amount of fuel (that very well could weigh as much or more than the airbags). Instead, the Apollo CM and the CEV are designed to plunge directly into the Earth's upper atmosphere, literally burning off the excess velocity through atmospheric drag. This requires a larger heat shield, but lowers the mission complexity and fuel the spacecraft needs to carry.
How many people would seriously want to do this, say launch something ~100cm^3 & 100 grams for ~10K? If 10 people/groups would sign up, not only would they get their stuff in space, but they could help out a university team doing some of the heavy lifting Comments? Suggestions? Reservations?
It seems that everyone forgets that the Russians had their own (almost identical) version of the Space Shuttle called Buran. The Soviets/Russians had completed or were finishing construction of 5 space capable vehicles. 1 of which actually flew into space and a second that was being readied for launch before the plug was pulled. In the end, NASA has gotten well over 100 manned flights from its program, the Soviets/Russians only got 1 unmanned. I am not suggesting that NASA is perfect, but its Russian counterpart is not either.
Just dealing with the rocket technology: The US held a distinct disadvantage at the beginning of the space race, which consisted of little more than placing different objects or passengers on slightly modified ICBMs. The Soviets started out with a better vehicle because their nuclear warheads were heavier. The US had developed smaller munitions and had no need for large rockets/ICMBs. In the end, the United States was unsuccessful in building a rocket capable of sending men to the moon and the Soviet Union was not. The Saturn V had a perfect track record with 13 successful flights and no failures. The N-1 never reached even earth orbit and was canceled after 4 spectacular failures. Sounds like a pretty decisive victory to me.
NASA wants to make sure that attempting to repair the tiles is actually the best option. Up until post-Columbia, astronauts did not travel "under" the shuttle. There is a non-insignificant risk that the astronaut, robotic arm, or tools could impact the tiles and cause even more serious damage. When you factor in the inherent danger (although fairly minimal) in an EVA, add to it that there will be no visual on the space walker from the shuttle, the risks may not be worth it to fix what might be benign and superficial damage.
The folks at NASA understand the risks and they have already stated that foregoing a repair is only a risk to the shuttle that might require repairs on the ground.
Mercury*, Gemini, Apollo, and Soyuz all use(d) ablative heatshields that burn off as they reenter. The ceramic tiles (and carbon-carbon) are the most common material used in reusable heat shields like those on the shuttle (also a number of next gen spacecraft (X-Series and the Kistler K-1). There were numerous concerns with the heatsheilds on previous spacecraft including concerns over John Glenn's Mercury flight (they kept the orbital maneuvering unit connected to the craft to hold the heatshield on) and Apollo 13, where there were concerns that the cold temperatures (the heaters were turned off after the explosion) may have cracked the heat shield. *The first two Mercury flights were suborbital and did not require the same type of heatshield because of lower temperatures.
The U.S. has made a strong attempt to keep military and civilian space programs separate. From the beginning, NASA was created as the civilian space program. There are undeniable technology overlaps and the US learned early on (Vanguard) that ignoring military equipment and technology was folly and would hold back the goals of the program. Except for a couple shuttle flights (which was at the same time a company could rent out a shuttle launch for their satellites), most everything has been public and decidedly civilian. This is in stark contrast to many of the other space programs in the world. Sputnik was a part of the R-9 ICBM program, and the chinese space program was an outgrowth of the Peoples Liberation Army. And surely the US military and intelligence services have been involved in space, but they are separate. Just take a look at congressional spending, you have 3 forms of space funding: NASA (Civilian), Military, and Black. Go ahead and bash the Military and Black budgets, but please make the distinction between NASA's civilian program and the military/intelligence stuff.
The good news is that there does not seem to be anyone inhabiting space as far as we can see (and probably travel for at least thousands of years) so that is a nonissue in this case.
I have personally survived 3 years of engineering at U of Maryland using only Calc for spreadsheets. And yes, I survived high school too.