Guys, guys, lets not try to reengineer the shuttles. I am sure the engineers at NASA and Boeing have done there research and know what heat resistant materails are out there and what works best...
...anyway this was an email from Laurel Clark, who was a mission specialist on STS 107 published in USA today:
[quote] "Hello from above our magnificent planet Earth. the perspective is truly awe-inspiring...lightening spreading over the Pacific. the aurora australis lighting up the entine visable horizon with the city glow of Australia below...the vast plains of Africa and the dunes of Cape Horn, rivers breaking through tall mountain passes, the scars of humanity, the continuous line of life extending from North America, though Central America and into South America, a crescent moon setting over the linb of our blue planet.
"I feel blessed to be here representing our country and carrying out the research of scientists around the world. I hope you feel the positive energy that I beamed to the whole planet as we glided over our shared planet."[/quote]
Rehashing shuttle design is okay, its just SB is being a tad bit enthusiastic, Luckily we have SamuelK here who has his engineering degree to keep him close to the ground [img]http://216.15.145.59/mainforums/wink.gif[/img]
[quote]Guys, guys, lets not try to reengineer the shuttles. I am sure the engineers at NASA and Boeing have done there research and know what heat resistant materails are out there and what works best...[/quote]
There's nothing wrong with discussing this stuff. There's always a better way to do things.
I seriously think Bush isnt going to let them ground the shuttles, and he will probably push for a replacement, NASA already had its first real budget increase in a while, with this next year them picking up 500 million, not alot, but hell its something, and I expect we will see them get more. Frankly the G1 and Clinton administrations put the big hurt on NASA.
[quote]Originally posted by samuelk:
[b] The flaw in your argument is that you're assuming that the guy with the nail gun can't also have a hammer as backup. [/b][/quote]
Moving away from the nuts and bolts of shuttle [materials] (re)design, I'd like to bring up something from the news reports today.
NASA stated that they didn't have pictures taken of the shuttle wing because they wouldn't be useful; An astronaut couldn't perform an EVA because they weren't planned and there were no clamp points on the underside of the wing and the shuttle wasn't carrying any MMUs, and even if they found a problem there wasn't anything they could do. Also I read an (unconfirmed) message that due to the space hab configuration on this flight there wasn't an external airlock, the shuttle airlock was connected directly to spacehab.
I think larger than the specific materials used to construct the shuttle; the idea that there is no way to determine the extent of a potential problem, and no way to correct one if found while on orbit is highly disturbing. I think any replacement or redesign for the shuttle should consider these areas.
Possibly a small autonomous space craft could be carried; nothing more than a camcorder grafted to some thruster jets. Just enough to maneuver a camera around to take a look. Or even a lightweight arm with a camera mounted with enough joints to look at all points on the spacecraft.
The if a problem is detected some though should be given to backup plans. Currently NASA couldn't prep and launch another shuttle soon enough to rescue the astronaut if a problem preventing deorbit was found; and moving between two shuttles on orbit would be dangerous as they couldn't dock with each other. Columbia only had enough constables to stay on orbit another 5 to 7 days, after that they would have had to deorbit or die in space.
The Delta-V required for an unplanned docking with the space station is enough to render that impossible; but maybe NASA could come up with a resupply ship to allow them time to work. Or if they ever build the full sized crew return vehicle for the space station, they could keep one prepped on the ground to lift on a dumb (non-man rated) booster and have the astronauts transfer to that to return safely. If so they should either design a docking mechanism, or a more flexible solution develop some sort of automated throw line to connect undocked ships and train the crew in EVA ship to ship movement. i.e. connect this guide line, clip the space suit to it and move down the line to the other craft.
Anyway just some thoughts, but any redesign should consider problem detection and mitigation so that we aren't left in a situation where we have to cross our fingers and hope...
Good points, but the truth is you can't plan for everything. Given that there are no other nations with manned-space programs besides the US and Russia, there is little reason to equip every vessel with a universal docking apparatus; there just won't be any one there to pick you up.
As for the camera-pod concept, its a nice-to-have, but presents other problems, such as carrying an independent thruster system inside the cargo bay, means of launch, additional space required for the maneuvering / communications system(s), and what would be accomplished by having pictures of a damaged underside or wing edge (beside allowing additional time to pray before you die). As NASA has pointed out, even if they had known there was damage, there was nothing they could do about the approach to change things. The shuttle already uses the approach with the least structural and thermodynamic stress on the orbitter.
As for a separatable crew safety module that the press keeps throwing up, what is the point? There is no way that an Apollo-style, ablative shield vehicle would have survived at the reentry point. First, there was no time from the problem detection to catastrophic failures for the crew to have moved into sch a vehicle. Second, even if the crew had been able to transfer, the angle of descent was already established for the shuttle's configuration, not likely to be the same needed for a different configuration. Third, we have no experience with separating and maneuvering vehicles during a descent stage.
As for a nose-cone-that-separates-and-descends by-parachute module, again, the structural stresses at the point where the accident occured would still have destroyed the crew compartment.
The best approach is what is being used: plan for everything you can, plan for contingencies, and build in redundancy. There will always be points in any design where you cannot engineer in more safety.
What we as a nation and people [b]cannot[/b] let happen is that we no longer consider space exploration to be worth the cost. Every great generation has paid for its discoveries with the some of the lives of those willing to risk them for a greater good, be it sociological (think Plymouth), economic (think Jamestown and California Gold Rush), or scientific (think Nroth and South pole exploration). If we ever hope to remain strong, we must be willing to stretch beyond our comfort zone.
To paraphase a famous man, we go to low earth orbit, the moon, Mars, and beyond, not because these things are easy, but because they are difficult.
[quote]
the ceramic tiles are a favourite with boffins.... blow torch on one side.. you feel nothing on the other... until you drop it and it scatters in pieces across the floor... lots of OOO"s and AAAAAAh's involved and how impressed wouldn't you be if he showed you a block of plywood ??
[/quote]
It wasn't that fragile. It felt like a cross between foam rubber and styrofoam. It certainly would not have shattered on the floor like you say.
------------------
AnlaShok, Captain of the Gray Hand of Fate Squadron
Sidhe-1
Wielder of the Big Heavy Hammer of Obvious Truth
"FABRICATI DIEM, PVNC!"
Been quiet for most of this.. but I can't be quiet any longer.
Bobo, there is ALWAYS room for improvements. It's when you place restrictions on yourself that you find limitations. In the case of the shuttle, the restrictions are cost and weight.
As for who said the shuttle didn't need work because it wasn't "old". That's complete bullshit. The shuttle was designed using 1970's technology and engineering. Yes, the ones that are flying now have seen vast improvements to what they were when they were first built. But the foundation is the same. If you build a house on sand, it doesn't matter how you build it or what the house looks like, it's still built on sand. I'm not knocking the shuttles design as saying it's bad.. but it CAN be improved on..something I really think they should be doing. But, that's just my opinion.
Whoever said the B-52's have been operating for a long time and they're doing fine in argument to redesigning the shuttle,.. Get your head out of your ass. The only similarity the shuttle bears to the B-52 is that they both have wings. Bottom line is that the shuttle isn't even in the same LEAGUE as any other aircraft. The B-52 doesn't even come close to experienceing the kind of stresses that the shuttle experiences. All the B-52 essentially does is carry it's ordinance from point A to point B where it releases it. It doesn't slam into the atmosphere at speeds exceeding mach 18. It doesn't experience the G-forces of even a jet fighter, let alone those that the shuttle experiences. It doesn't need to deal with extreme opposites of heat or cold as the shuttle does, nor does it have to be able to manuver with the precision that the space shuttle does, in zero G I might add. Quite frankly, the B-52 exists today because there is no NEED to improve on it's design. We dont conduct Air to Ground warfare in the same way we did when the B-52 was first built. We don't level entire cities just to destroy a factory anymore. Yes, it still has it's uses but those uses are very specific and it does them well enough that there is no NEED to improve on it. The space shuttle on the other hand is our ONLY CURRENT means of manned space exploration. The B-52's life span is nearing an end according to modern warfare. The space shuttle's is nearing an end simply because we need a safer, more efficient and cheaper way to travel to and from space.
sorry for my rant folks but the innane yet thoughtless babble was getting on my nerves... suppose that's why I don't come here much anymore. Too much self rightousness and not enough actual thought.
[quote]Originally posted by bobo:
[b]....and what would be accomplished by having pictures of a damaged underside or wing edge (beside allowing additional time to pray before you die).[/b][/quote]
Evidence.
Which also would save [b]A LOT[/b] of time, money, effort and resources and would provide the truth instead of having the most likely/possible truth after inspections.
Also if you know that something is damaged you can at least think if something could possibly be done and try to do something.
I know that it is somewhat impractical with the shuttles _as currently designed and run_ to include a camera system and an escape module.
But since NASA doesn't have the materials on hand to build another shuttle, like Endeavour post Challanger, I thought it would be interesting to get a discussion started on what new safty features / disaster planning you though should go into a shuttle replacement or shuttle mark 2.
Just becuase we can't launch a shuttle (or anything else) to rescue a shuttle (or at least the crew) today doesn't mean we shouldn't think about building the capability.
[This message has been edited by Jon_S (edited 02-04-2003).]
[quote]Originally posted by samuelk:
[b] There's nothing wrong with discussing this stuff. There's always a better way to do things.[/b][/quote]
I agree and I'm not saying we should stop discussing improvements or alternatives to the current methods of space travel, I just want to make sure the discussion stays focused on the greater picture, not whether or not plywood makes a good heat sheild.
Originaly the shuttle fleet was suppost to be 12 craft, which would have allowed for a second shuttle to be launched to conduct a rescue, in the event the first had an accident.
[quote]Originally posted by Tyvar:
[b]
Originaly the shuttle fleet was suppost to be 12 craft, which would have allowed for a second shuttle to be launched to conduct a rescue, in the event the first had an accident.[/b][/quote]
And there was supposed to be a launch a week, instead of one a month. And there was supposed to be a space station and a Mars mission to go along with the Shuttle.
Thank you Dick Nixon, that man who made NASA's three point plan for conquring space a one point plan for conquring low orbit.
There's been some talk of escape systems and rescues operations, but I don't think either would have been much use in this case or for that matter several other possible failures. Its been said by some aerospace engineers that most escape methods often have such limited applications as to make them impractical. There is no all-encompassing escape method that is practical for space travel.
If there had been a shuttle ready to go, (which some have implied that Atlantis could have been ready in a week) and if they could have gotten a good shot of the damage, it would still have to be very, very severe to risk sending another shuttle up. It would have to be in a situation where there was a catastrophic failure in space.
An escape system would be of little use in the case also, since any escape system would have to withstand the same rigors as the shuttle itself. For example if there was, say, an ejection pod, at the point that the shuttle was in it decent, the pod would be ejecting into the atmosphere at the same 12,500 mph the shuttle had been traveling, so it too would need to have heat shielding and attitude control. This would be such a great weight penalty as to make it impractical.
[quote]For example if there was, say, an ejection pod, at the point that the shuttle was in it decent, the pod would be ejecting into the atmosphere at the same 12,500 mph the shuttle had been traveling, so it too would need to have heat shielding and attitude control. This would be such a great weight penalty as to make it impractical.[/quote]
That's not quite as big of a deal as the altitude. Current shuttle escape procedures are only really effective at an altitude of 40,000 feet or less.
[quote]Originally posted by Keyan:
[b]...but when it's under 40k feet, it's also not heating to 3,000 degrees anymore...that's the point he's making.[/b][/quote]
Btw, anyone know why it could not have been possible to rescue the crew to ISS in case they would've known that the shuttle had damage and would've been unable to get back on Earth? Just wondering why that would be not possible to do?
The Columbia was equipped with the spacelab for this mission, so it didn't have the docking mount to dock with the station. It was not equipped with an airlock at all since the only airlock was already hooked into the lab.
That and I heard somewhere that the Delta-V for intercepting the station was outside of the fuel capacity of the shuttle for this flight. Basically, it didn't have the gas to change it's orbit enough to meet up with the station.
So Columbia had not way to dock with ISS? IF they did, they could have all transfered into the Souyez (sp) craft and used it to return to earth (again, if this was possible and if they had found the problem). Then just autopilot Columbia into the sun.
The Soyuz can only hold 3. I don't think the life support systems on the station could support 10, assuming there was some way to get the crew aboard (which would be so dangerous, you wouldn't want to go back to the shuttle). One little side note...as much fun as launching the shuttle into the sun would be, it also wouldn't have enough gas to make a orbit breakway burn...it would have to go through reentry over the ocean or something.
All of this talk is really trivial anyway...I think looking towards the future for a better system is the best answer.
just to be 100% crystal... moon sourced concrete, as thick as you want it, shed once the speed of the vehicle is down to sane levelss, deploy chutes and down you come gently, reuse the actual vehicle
but use 'throw away' heat sheilds, much in the way we throw away tanks on the way up
I still think the Shuttle itself is a flawed concept given our current technology, wings and shallow angles of dive through the interface is asking for trouble, the shorter you can make the journey through that 'hell' the better
just imagine, if the shuttle had no wings they wouldnt have been damaged and perhaps wed have seven astronauts rather than seven partially cremated corpses
I also heard that the Shuttle runs at its core systems... 286 chips... thats a worry if there is any truth in it
I also have no problem with this debate... the only problem I have is when the debate is not focused on the topic... but on winning points, on winning the debate...destryoing the debator and not the arguement put foward. May I suggest you look at what you post with that in mind...
~~~
without throwing any aspersions at any of my august fellows... sometimes a degree in Engineering or anything else for that matter is as much a ball and chain as it is a useful tool.
with everything you learn you run the risk of establishing a pattern of thought which becomes a groove in your mind, one you find hard to leave
everything is mutable, every rule you come to depend on may well be built on sandd
remember the world was flat once... till someone begged to differ...
perhaps gravity isnt a constant... that would certainly change the way we look at physics rather markedly
maybe the shuttle is a dog and we simply dont know it yet...perhaps we'll look back at the shuttle like the boys at Boeing look back at the Wright Flyer..
but we will never get to that point without giving a few sacred cows an enema, or even turn them into burgers...
funny how the shuttle is black and white.... just like a jersey
"The man who gives Sacred Cow enema always get covered in shit".... me 3/2/2003
SB, if you havent noticed everybody is saying the problem with the shuttle is its friggin old, and needs to be replaced, what your disagreeing about is HOW
Ablative shielding has its own problems, along with expendable vehicles. Frankly WE DO have the means to do better, here Im going to dig up a link from another board Im a lurker on, where you can see comments from somebody involved with the venture star project.
[url="http://pub165.ezboard.com/fwarships1discussionboardsfrm8.showMessage?topicID=1243.topic&index=13"]http://pub165.ezboard.com/fwarships1discussionboardsfrm8.showMessage?topicID=1243.topic&index=13[/url]
Everybody click the link! its fairly informative, hell the whole board is, thats why I read what they write, its a fairly small community, and these peoples credentials have been established already
Anyways, a shuttle replacement shouldnt be to difficult, and honestly considering the weirdness in the new budget I think one is underway, but not under NASA direction, but under the Air Force
[quote]Originally posted by shadow boxer:
[B]just to be 100% crystal... moon sourced concrete, as thick as you want it, shed once the speed of the vehicle is down to sane levelss, deploy chutes and down you come gently, reuse the actual vehicle[/quote]
Concrete is heavy. Too heavy to use for a vehicle entering the atmosphere. Plus, concrete doesn't hold up well to high temperatures.
In your happy fantasy land, sure you can make the concrete shield as thick as you want...but here in the real universe, there's a thing called mass and inertia to consider. The heavier the ship, the more fuel it takes to move it, and the harder it will be to stop it.
It's one thing to come up with innovative ways to do something...it's another to ignore the laws of physics and material properties when doing so.
[quote]I still think the Shuttle itself is a flawed concept given our current technology, wings and shallow angles of dive through the interface is asking for trouble, the shorter you can make the journey through that 'hell' the better[/quote]
The shorter the journey, the faster you have to go, and the quicker you have to stop. That's going to be hell on your passengers and cargo.
[quote]just imagine, if the shuttle had no wings they wouldnt have been damaged and perhaps wed have seven astronauts rather than seven partially cremated corpses[/quote]
Yeah, and if the Challenger had no engines it wouldn't have blown up in 1986. What's your point?
[quote]I also heard that the Shuttle runs at its core systems... 286 chips... thats a worry if there is any truth in it[/quote]
That's incorrect. The 5 main shuttle computers run HAL/S (High-order Assembly Language/Shuttle). Each of these computers weight around 60 pounds and has 1 megabyte of memory. The CPUs are IBM AP-101S processors.
And it's not as if they just bought a processor from a local computer store and plugged it into a stock motherboard. All of these systems are highly specialized, and specifically designed to do their job and ONLY their job.
First you're telling people that hi-tech isn't always the answer, and now you're complaining about a rather low-tech processor. Which is it?
But FYI, there are all kinds of processors on the shuttle...engine computers, climate controllers, communications computers, navigational systems, radiation shielded components, etc. The computer that controls the shuttle's main engines is a 68000-based processor with 128K of RAM. It's not runing Windows; there's no need for the extra processing power. These computers don't do much, but by being simpler, they are VERY reliable.
[quote]I also have no problem with this debate... the only problem I have is when the debate is not focused on the topic... but on winning points, on winning the debate...destryoing the debator and not the arguement put foward. May I suggest you look at what you post with that in mind...[/quote]
Maybe if you'd avoid calling people names, the debate would be a little less ego-focused.
~~~
[quote]without throwing any aspersions at any of my august fellows... sometimes a degree in Engineering or anything else for that matter is as much a ball and chain as it is a useful tool.[/quote]
First you ask for qualifications (when you asked who had done studies on concrete), and then you try to play down the same type of qualifications. It sounds like YOU'RE the one trying to win an argument.
[quote]with everything you learn you run the risk of establishing a pattern of thought which becomes a groove in your mind, one you find hard to leave[/quote]
I have a degree in mechanical engineering. If it's one thing I was taught, it's how to think freely. Just because I'm educated in a certain area doesn't mean my thought process is restricted.
But that also doesn't mean I can't see huge flaws in many of the things you suggest.
[quote]perhaps gravity isnt a constant... that would certainly change the way we look at physics rather markedly
maybe the shuttle is a dog and we simply dont know it yet...perhaps we'll look back at the shuttle like the boys at Boeing look back at the Wright Flyer..[/quote]
I don't think anyone here is saying that the shuttle is the perfect solution. There's always something better.
[This message has been edited by samuelk (edited 02-05-2003).]
Comments
...anyway this was an email from Laurel Clark, who was a mission specialist on STS 107 published in USA today:
[quote] "Hello from above our magnificent planet Earth. the perspective is truly awe-inspiring...lightening spreading over the Pacific. the aurora australis lighting up the entine visable horizon with the city glow of Australia below...the vast plains of Africa and the dunes of Cape Horn, rivers breaking through tall mountain passes, the scars of humanity, the continuous line of life extending from North America, though Central America and into South America, a crescent moon setting over the linb of our blue planet.
"I feel blessed to be here representing our country and carrying out the research of scientists around the world. I hope you feel the positive energy that I beamed to the whole planet as we glided over our shared planet."[/quote]
Jake
There's nothing wrong with discussing this stuff. There's always a better way to do things.
[b] The flaw in your argument is that you're assuming that the guy with the nail gun can't also have a hammer as backup. [/b][/quote]
Apparently it's a flaw for NASA too...
[img]http://216.15.145.59/mainforums/frown.gif[/img]
[b] Apparently it's a flaw for NASA too...
[img]http://216.15.145.59/mainforums/frown.gif[/img][/b][/quote]
Doesn't really apply to NASA's situation.
Sometimes, even your hammer breaks.
NASA stated that they didn't have pictures taken of the shuttle wing because they wouldn't be useful; An astronaut couldn't perform an EVA because they weren't planned and there were no clamp points on the underside of the wing and the shuttle wasn't carrying any MMUs, and even if they found a problem there wasn't anything they could do. Also I read an (unconfirmed) message that due to the space hab configuration on this flight there wasn't an external airlock, the shuttle airlock was connected directly to spacehab.
I think larger than the specific materials used to construct the shuttle; the idea that there is no way to determine the extent of a potential problem, and no way to correct one if found while on orbit is highly disturbing. I think any replacement or redesign for the shuttle should consider these areas.
Possibly a small autonomous space craft could be carried; nothing more than a camcorder grafted to some thruster jets. Just enough to maneuver a camera around to take a look. Or even a lightweight arm with a camera mounted with enough joints to look at all points on the spacecraft.
The if a problem is detected some though should be given to backup plans. Currently NASA couldn't prep and launch another shuttle soon enough to rescue the astronaut if a problem preventing deorbit was found; and moving between two shuttles on orbit would be dangerous as they couldn't dock with each other. Columbia only had enough constables to stay on orbit another 5 to 7 days, after that they would have had to deorbit or die in space.
The Delta-V required for an unplanned docking with the space station is enough to render that impossible; but maybe NASA could come up with a resupply ship to allow them time to work. Or if they ever build the full sized crew return vehicle for the space station, they could keep one prepped on the ground to lift on a dumb (non-man rated) booster and have the astronauts transfer to that to return safely. If so they should either design a docking mechanism, or a more flexible solution develop some sort of automated throw line to connect undocked ships and train the crew in EVA ship to ship movement. i.e. connect this guide line, clip the space suit to it and move down the line to the other craft.
Anyway just some thoughts, but any redesign should consider problem detection and mitigation so that we aren't left in a situation where we have to cross our fingers and hope...
As for the camera-pod concept, its a nice-to-have, but presents other problems, such as carrying an independent thruster system inside the cargo bay, means of launch, additional space required for the maneuvering / communications system(s), and what would be accomplished by having pictures of a damaged underside or wing edge (beside allowing additional time to pray before you die). As NASA has pointed out, even if they had known there was damage, there was nothing they could do about the approach to change things. The shuttle already uses the approach with the least structural and thermodynamic stress on the orbitter.
As for a separatable crew safety module that the press keeps throwing up, what is the point? There is no way that an Apollo-style, ablative shield vehicle would have survived at the reentry point. First, there was no time from the problem detection to catastrophic failures for the crew to have moved into sch a vehicle. Second, even if the crew had been able to transfer, the angle of descent was already established for the shuttle's configuration, not likely to be the same needed for a different configuration. Third, we have no experience with separating and maneuvering vehicles during a descent stage.
As for a nose-cone-that-separates-and-descends by-parachute module, again, the structural stresses at the point where the accident occured would still have destroyed the crew compartment.
The best approach is what is being used: plan for everything you can, plan for contingencies, and build in redundancy. There will always be points in any design where you cannot engineer in more safety.
What we as a nation and people [b]cannot[/b] let happen is that we no longer consider space exploration to be worth the cost. Every great generation has paid for its discoveries with the some of the lives of those willing to risk them for a greater good, be it sociological (think Plymouth), economic (think Jamestown and California Gold Rush), or scientific (think Nroth and South pole exploration). If we ever hope to remain strong, we must be willing to stretch beyond our comfort zone.
To paraphase a famous man, we go to low earth orbit, the moon, Mars, and beyond, not because these things are easy, but because they are difficult.
------------------
bobo
<*>
B5:ITF
the ceramic tiles are a favourite with boffins.... blow torch on one side.. you feel nothing on the other... until you drop it and it scatters in pieces across the floor... lots of OOO"s and AAAAAAh's involved and how impressed wouldn't you be if he showed you a block of plywood ??
[/quote]
It wasn't that fragile. It felt like a cross between foam rubber and styrofoam. It certainly would not have shattered on the floor like you say.
------------------
AnlaShok, Captain of the Gray Hand of Fate Squadron
Sidhe-1
Wielder of the Big Heavy Hammer of Obvious Truth
"FABRICATI DIEM, PVNC!"
Bobo, there is ALWAYS room for improvements. It's when you place restrictions on yourself that you find limitations. In the case of the shuttle, the restrictions are cost and weight.
As for who said the shuttle didn't need work because it wasn't "old". That's complete bullshit. The shuttle was designed using 1970's technology and engineering. Yes, the ones that are flying now have seen vast improvements to what they were when they were first built. But the foundation is the same. If you build a house on sand, it doesn't matter how you build it or what the house looks like, it's still built on sand. I'm not knocking the shuttles design as saying it's bad.. but it CAN be improved on..something I really think they should be doing. But, that's just my opinion.
Whoever said the B-52's have been operating for a long time and they're doing fine in argument to redesigning the shuttle,.. Get your head out of your ass. The only similarity the shuttle bears to the B-52 is that they both have wings. Bottom line is that the shuttle isn't even in the same LEAGUE as any other aircraft. The B-52 doesn't even come close to experienceing the kind of stresses that the shuttle experiences. All the B-52 essentially does is carry it's ordinance from point A to point B where it releases it. It doesn't slam into the atmosphere at speeds exceeding mach 18. It doesn't experience the G-forces of even a jet fighter, let alone those that the shuttle experiences. It doesn't need to deal with extreme opposites of heat or cold as the shuttle does, nor does it have to be able to manuver with the precision that the space shuttle does, in zero G I might add. Quite frankly, the B-52 exists today because there is no NEED to improve on it's design. We dont conduct Air to Ground warfare in the same way we did when the B-52 was first built. We don't level entire cities just to destroy a factory anymore. Yes, it still has it's uses but those uses are very specific and it does them well enough that there is no NEED to improve on it. The space shuttle on the other hand is our ONLY CURRENT means of manned space exploration. The B-52's life span is nearing an end according to modern warfare. The space shuttle's is nearing an end simply because we need a safer, more efficient and cheaper way to travel to and from space.
sorry for my rant folks but the innane yet thoughtless babble was getting on my nerves... suppose that's why I don't come here much anymore. Too much self rightousness and not enough actual thought.
[b] Too much self rightousness and not enough actual thought.[/b][/quote]
Amen
[b]....and what would be accomplished by having pictures of a damaged underside or wing edge (beside allowing additional time to pray before you die).[/b][/quote]
Evidence.
Which also would save [b]A LOT[/b] of time, money, effort and resources and would provide the truth instead of having the most likely/possible truth after inspections.
Also if you know that something is damaged you can at least think if something could possibly be done and try to do something.
- PJH
But since NASA doesn't have the materials on hand to build another shuttle, like Endeavour post Challanger, I thought it would be interesting to get a discussion started on what new safty features / disaster planning you though should go into a shuttle replacement or shuttle mark 2.
Just becuase we can't launch a shuttle (or anything else) to rescue a shuttle (or at least the crew) today doesn't mean we shouldn't think about building the capability.
[This message has been edited by Jon_S (edited 02-04-2003).]
[b] There's nothing wrong with discussing this stuff. There's always a better way to do things.[/b][/quote]
I agree and I'm not saying we should stop discussing improvements or alternatives to the current methods of space travel, I just want to make sure the discussion stays focused on the greater picture, not whether or not plywood makes a good heat sheild.
Jake
[b]
Originaly the shuttle fleet was suppost to be 12 craft, which would have allowed for a second shuttle to be launched to conduct a rescue, in the event the first had an accident.[/b][/quote]
And there was supposed to be a launch a week, instead of one a month. And there was supposed to be a space station and a Mars mission to go along with the Shuttle.
Thank you Dick Nixon, that man who made NASA's three point plan for conquring space a one point plan for conquring low orbit.
If there had been a shuttle ready to go, (which some have implied that Atlantis could have been ready in a week) and if they could have gotten a good shot of the damage, it would still have to be very, very severe to risk sending another shuttle up. It would have to be in a situation where there was a catastrophic failure in space.
An escape system would be of little use in the case also, since any escape system would have to withstand the same rigors as the shuttle itself. For example if there was, say, an ejection pod, at the point that the shuttle was in it decent, the pod would be ejecting into the atmosphere at the same 12,500 mph the shuttle had been traveling, so it too would need to have heat shielding and attitude control. This would be such a great weight penalty as to make it impractical.
Jake
That's not quite as big of a deal as the altitude. Current shuttle escape procedures are only really effective at an altitude of 40,000 feet or less.
[b]...but when it's under 40k feet, it's also not heating to 3,000 degrees anymore...that's the point he's making.[/b][/quote]
Chicken, egg; egg, chicken...
- PJH
That and I heard somewhere that the Delta-V for intercepting the station was outside of the fuel capacity of the shuttle for this flight. Basically, it didn't have the gas to change it's orbit enough to meet up with the station.
- PJH
All of this talk is really trivial anyway...I think looking towards the future for a better system is the best answer.
yay....
not
just to be 100% crystal... moon sourced concrete, as thick as you want it, shed once the speed of the vehicle is down to sane levelss, deploy chutes and down you come gently, reuse the actual vehicle
but use 'throw away' heat sheilds, much in the way we throw away tanks on the way up
I still think the Shuttle itself is a flawed concept given our current technology, wings and shallow angles of dive through the interface is asking for trouble, the shorter you can make the journey through that 'hell' the better
just imagine, if the shuttle had no wings they wouldnt have been damaged and perhaps wed have seven astronauts rather than seven partially cremated corpses
I also heard that the Shuttle runs at its core systems... 286 chips... thats a worry if there is any truth in it
I also have no problem with this debate... the only problem I have is when the debate is not focused on the topic... but on winning points, on winning the debate...destryoing the debator and not the arguement put foward. May I suggest you look at what you post with that in mind...
~~~
without throwing any aspersions at any of my august fellows... sometimes a degree in Engineering or anything else for that matter is as much a ball and chain as it is a useful tool.
with everything you learn you run the risk of establishing a pattern of thought which becomes a groove in your mind, one you find hard to leave
everything is mutable, every rule you come to depend on may well be built on sandd
remember the world was flat once... till someone begged to differ...
perhaps gravity isnt a constant... that would certainly change the way we look at physics rather markedly
maybe the shuttle is a dog and we simply dont know it yet...perhaps we'll look back at the shuttle like the boys at Boeing look back at the Wright Flyer..
but we will never get to that point without giving a few sacred cows an enema, or even turn them into burgers...
funny how the shuttle is black and white.... just like a jersey
"The man who gives Sacred Cow enema always get covered in shit".... me 3/2/2003
in fact... thats my new sig....
Ablative shielding has its own problems, along with expendable vehicles. Frankly WE DO have the means to do better, here Im going to dig up a link from another board Im a lurker on, where you can see comments from somebody involved with the venture star project.
[url="http://pub165.ezboard.com/fwarships1discussionboardsfrm8.showMessage?topicID=1243.topic&index=13"]http://pub165.ezboard.com/fwarships1discussionboardsfrm8.showMessage?topicID=1243.topic&index=13[/url]
Everybody click the link! its fairly informative, hell the whole board is, thats why I read what they write, its a fairly small community, and these peoples credentials have been established already
Anyways, a shuttle replacement shouldnt be to difficult, and honestly considering the weirdness in the new budget I think one is underway, but not under NASA direction, but under the Air Force
[B]just to be 100% crystal... moon sourced concrete, as thick as you want it, shed once the speed of the vehicle is down to sane levelss, deploy chutes and down you come gently, reuse the actual vehicle[/quote]
Concrete is heavy. Too heavy to use for a vehicle entering the atmosphere. Plus, concrete doesn't hold up well to high temperatures.
In your happy fantasy land, sure you can make the concrete shield as thick as you want...but here in the real universe, there's a thing called mass and inertia to consider. The heavier the ship, the more fuel it takes to move it, and the harder it will be to stop it.
It's one thing to come up with innovative ways to do something...it's another to ignore the laws of physics and material properties when doing so.
[quote]I still think the Shuttle itself is a flawed concept given our current technology, wings and shallow angles of dive through the interface is asking for trouble, the shorter you can make the journey through that 'hell' the better[/quote]
The shorter the journey, the faster you have to go, and the quicker you have to stop. That's going to be hell on your passengers and cargo.
[quote]just imagine, if the shuttle had no wings they wouldnt have been damaged and perhaps wed have seven astronauts rather than seven partially cremated corpses[/quote]
Yeah, and if the Challenger had no engines it wouldn't have blown up in 1986. What's your point?
[quote]I also heard that the Shuttle runs at its core systems... 286 chips... thats a worry if there is any truth in it[/quote]
That's incorrect. The 5 main shuttle computers run HAL/S (High-order Assembly Language/Shuttle). Each of these computers weight around 60 pounds and has 1 megabyte of memory. The CPUs are IBM AP-101S processors.
And it's not as if they just bought a processor from a local computer store and plugged it into a stock motherboard. All of these systems are highly specialized, and specifically designed to do their job and ONLY their job.
First you're telling people that hi-tech isn't always the answer, and now you're complaining about a rather low-tech processor. Which is it?
But FYI, there are all kinds of processors on the shuttle...engine computers, climate controllers, communications computers, navigational systems, radiation shielded components, etc. The computer that controls the shuttle's main engines is a 68000-based processor with 128K of RAM. It's not runing Windows; there's no need for the extra processing power. These computers don't do much, but by being simpler, they are VERY reliable.
[quote]I also have no problem with this debate... the only problem I have is when the debate is not focused on the topic... but on winning points, on winning the debate...destryoing the debator and not the arguement put foward. May I suggest you look at what you post with that in mind...[/quote]
Maybe if you'd avoid calling people names, the debate would be a little less ego-focused.
~~~
[quote]without throwing any aspersions at any of my august fellows... sometimes a degree in Engineering or anything else for that matter is as much a ball and chain as it is a useful tool.[/quote]
First you ask for qualifications (when you asked who had done studies on concrete), and then you try to play down the same type of qualifications. It sounds like YOU'RE the one trying to win an argument.
[quote]with everything you learn you run the risk of establishing a pattern of thought which becomes a groove in your mind, one you find hard to leave[/quote]
I have a degree in mechanical engineering. If it's one thing I was taught, it's how to think freely. Just because I'm educated in a certain area doesn't mean my thought process is restricted.
But that also doesn't mean I can't see huge flaws in many of the things you suggest.
[quote]perhaps gravity isnt a constant... that would certainly change the way we look at physics rather markedly
maybe the shuttle is a dog and we simply dont know it yet...perhaps we'll look back at the shuttle like the boys at Boeing look back at the Wright Flyer..[/quote]
I don't think anyone here is saying that the shuttle is the perfect solution. There's always something better.
[This message has been edited by samuelk (edited 02-05-2003).]