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There still seems something wrong in my view to returning to the capsule
way of getting back to earth. Its undignified, inconvenient and I'd have though rather unnecessary with what has been learned on the Shuttle. I've seen cost reasons, well maybe, and all sorts of other ideas for why Orion is a capsule, but I fear that the public, who have been used to seeing a landing on wheels will equate the new vehicle with the Apollo and Soyuz eras and think, hey, are we going backwards? I also notice a split occuring between the public 'all American's Lunar project propaganda and what a lot of the scientists, and other Nasa people seem to think, that it really needs to be international. This may well be because of the economics at the moment, but if nothing else, I feel realism needs to reign here, and I think in the end, it will either end badly or go international in some form. Space law. Who is working on this for international bases and stations? There is bound to be a need for it eventually. Brian -- Brian Gaff - Note:- In order to reduce spam, any email without 'Brian Gaff' in the display name may be lost. Blind user, so no pictures please! |
#2
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Brian Gaff wrote:
There still seems something wrong in my view to returning to the capsule way of getting back to earth. Its undignified, inconvenient and I'd have though rather unnecessary with what has been learned on the Shuttle. Unfortunatly, science and technology needed to make a reliable/cheap shuttlecraft do not exist yet. NASA has had much egg thrown at its face with a number of failed X projects to replace the shuttle. Being faced with a need to replace the shuttle and a desire to have a high propability of actually have something usable (instead of another cancelled project), they were forced to go with something old, simple and not too complex that can use technologies developped last century. And despite using all old technology, there are still doubts that the rocket will work. What I find a real shame is that in the late 1990s, that they didn't build one or two "new" shuttles that would have incorporated all of the improvements NASA knew it was capable of making. It would not have been revolutionary in terms of reducing costs, it would have been evolutionary. But it would have advanced the "state of the art". Going back to Apollo doesn't really advance the state of the art. |
#4
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"Brian Gaff" wrote in message m... There still seems something wrong in my view to returning to the capsule way of getting back to earth. Its undignified, inconvenient and I'd have though rather unnecessary with what has been learned on the Shuttle. I've seen cost reasons, well maybe, and all sorts of other ideas for why Orion is a capsule, but I fear that the public, who have been used to seeing a landing on wheels will equate the new vehicle with the Apollo and Soyuz eras and think, hey, are we going backwards? Form follows function. At the velocities to be encountered when returning to the moon, the Apollo CM shape and TPS is proven. There is no way that the shuttle could do the same. The much higher velocities mean much higher heating and aerodynamic forces, which the shuttle could not survive. As far as being inconvienent or undignified, with NASA envisioning a couple of lunar Orion flights per year, the flight rate is simply far too low for them to worry about convienence and dignity. I also notice a split occuring between the public 'all American's Lunar project propaganda and what a lot of the scientists, and other Nasa people seem to think, that it really needs to be international. This may well be because of the economics at the moment, but if nothing else, I feel realism needs to reign here, and I think in the end, it will either end badly or go international in some form. Right now it looks like if it ends badly, it will be because of Griffin's 1.5 launch architecture. Ares I in particular is eating up billions of dollars in development money with nothing yet flying. The Ares I-X flight is going to be a stunt. A four segment shuttle SRB with a dummy fifth segment, dummy upper stage, and dummy Orion. Very little useful data will be gained by this flight. It's just something quick and dirty that NASA can fly to make it appear like they're making progress, when the reality is that progress is slower and more expensive than anticipated. At this rate it's easy to predict that Ares V's costs will balloon as well, leading the policy makers to decide to "reevaluate" the program. My guess is there will be a "scaling back", as was done numerous times with Freedom/ISS, but how big that is has yet to be determined. Jeff -- "Many things that were acceptable in 1958 are no longer acceptable today. My own standards have changed too." -- Freeman Dyson |
#5
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"Brian Gaff" wrote in message m... According to the latest news also, they are even using a material for the heat shield that is very similar to the old version used back then. Admittedly thety could use something else down the line, but it still seems odd when, as you say, they are designing a very strange manned launch vehicle when many existing ones could, presumably be made man friendly at a lesser cost. I still think the heavy lift version would use the legacy Shuttle stuff, but why keep on with it for manned use. Everyone knows the only reason the Shuttle used them is basically to lift the full tank! I hope it works for their sake, but it will be a rough few minutes I'd imagine. Ares I is there to hide some of the development costs for Ares V, which would be the largest launch vehicle ever built. Ares I, in and of itself, is stupid. But that's obviously not the opinion of Mike Griffin, who single handedly shoved the 1.5 launch architecture down NASA's throat. Where are the ESAS appendices? As far as I know, the FOIA requests for them have not been fulfilled. Jeff -- "Many things that were acceptable in 1958 are no longer acceptable today. My own standards have changed too." -- Freeman Dyson |
#6
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"John Doe" wrote in message ... Brian Gaff wrote: There still seems something wrong in my view to returning to the capsule way of getting back to earth. Its undignified, inconvenient and I'd have though rather unnecessary with what has been learned on the Shuttle. Unfortunatly, science and technology needed to make a reliable/cheap shuttlecraft do not exist yet. NASA has had much egg thrown at its face with a number of failed X projects to replace the shuttle. This isn't necessarily true. NASA failed at X-33 because they picked the "winner" by which proposal had the most new technology. X-33 was testing too many new things at once. X-33 had a new shape (lifting body), new structure (composite, integrated with the tanks), new tanks (composite LOX and LH2 tanks), and new engines (linear aerospilke). Did I miss anything here? With such a grocery list of new technologies being integrated into a single vehicle, is it any wonder that one of them failed? A proper X vehicle is more like DC-X, which used off the shelf components to test vertical take off and landing along with quick turn around times for LOX/LH2 rocket engines. Another proper X vehicle would be a modified EELV upper stage to test technologies for in orbit cryogenic refueling. There have been several proposals to do just that with Centaur, but NASA has not funded them. Being faced with a need to replace the shuttle and a desire to have a high propability of actually have something usable (instead of another cancelled project), they were forced to go with something old, simple and not too complex that can use technologies developped last century. And despite using all old technology, there are still doubts that the rocket will work. While it's true Ares I is using "old technology", it's also using a very large SRB in a configuration that's never been used before on a manned vehicle. This is essentially the cause of Ares I's vibration problems. The other big problem with Ares I is performance. Since the switch from the SSME to the RS-68 in the upper stage, performance has been a huge issue. This isn't a problem with "old technology", but a problem with how that technology is being applied. In other words, it's a system engineering probelem, not a technological problem. What I find a real shame is that in the late 1990s, that they didn't build one or two "new" shuttles that would have incorporated all of the improvements NASA knew it was capable of making. It would not have been revolutionary in terms of reducing costs, it would have been evolutionary. But it would have advanced the "state of the art". This almost certainly would have cost a lot of money for little gain. The system engineering failures of the shuttle architecture would have remained (e.g. vulnerable TPS being hit by debris from the ET). Going back to Apollo doesn't really advance the state of the art. Advancing the "state of the art" is sometimes not necessary. In fact, I would argue that the state of the art is up to the task, specifically the EELV's. Duplicating their lift capability with Ares I is awfully silly. Jeff -- "Many things that were acceptable in 1958 are no longer acceptable today. My own standards have changed too." -- Freeman Dyson |
#7
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Jeff Findley wrote:
"Brian Gaff" wrote in message m... According to the latest news also, they are even using a material for the heat shield that is very similar to the old version used back then. Admittedly thety could use something else down the line, but it still seems odd when, as you say, they are designing a very strange manned launch vehicle when many existing ones could, presumably be made man friendly at a lesser cost. I still think the heavy lift version would use the legacy Shuttle stuff, but why keep on with it for manned use. Everyone knows the only reason the Shuttle used them is basically to lift the full tank! I hope it works for their sake, but it will be a rough few minutes I'd imagine. Ares I is there to hide some of the development costs for Ares V, which would be the largest launch vehicle ever built. Ares I, in and of itself, is stupid. But that's obviously not the opinion of Mike Griffin, who single handedly shoved the 1.5 launch architecture down NASA's throat. Where are the ESAS appendices? As far as I know, the FOIA requests for them have not been fulfilled. They will not be released because they contain proprietary cost data that is exempt from FOIA. (That said, it is inexcusable and illegal for a federal agency to fail to even respond to an FOIA request.) |
#8
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John Doe wrote:
What I find a real shame is that in the late 1990s, that they didn't build one or two "new" shuttles that would have incorporated all of the improvements NASA knew it was capable of making. It would not have been revolutionary in terms of reducing costs, it would have been evolutionary. But it would have advanced the "state of the art". Going back to Apollo doesn't really advance the state of the art. Submarines, which have equally stringent quality and safety requirements, have many mechanisms onboard unchanged since WWII or shortly after. They have a few unchanged from before WWI. In real world engineering 'works and is well known' is far more important than 'advances the state of the art'. D. -- Touch-twice life. Eat. Drink. Laugh. http://derekl1963.livejournal.com/ -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL |
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