Space Shuttle Theory

[Stamen0083]

Some radical ideas of mine...

1. I'm sure there is some way to reverse the gravity of something against the earth?

316188[/snapback]

When anti-gravitons are discovered, we'll let you know.

[Kin]

Some radical ideas of mine...

1. I'm sure there is some way to reverse the gravity of something against the earth?

316188[/snapback]

When anti-gravitons are discovered, we'll let you know.

316207[/snapback]

oke send me a spacemail to mars.

[JB0]

A. Scramjet is a kind of engine, not a ship.

B. Like all the other replacement concepts, it got scrapped at one point or another.

316172[/snapback]

A. I know that. It's some kind ramjet on steroids.

B. Anyone know where I can find any info on that concept. It seemed like an interesting one, but I don't know what that idea is called.

316174[/snapback]

Sorry, it sounded like you were presenting scramjet as the name of the ship.

Anyways... a scramjet is just a high-speed variant of the ramjet. It burns in faster environments than a standard ramjet does.

Part of the reason it was dropped may have been that it's not a single-engine atmospheric solution.

Ramjets and scramjets don't work in a subsonic environment, necessitating the addition of a conventional jet engine to get them past mach 1 before they're ignited.

Afraid I dunno where to find any info on the concept vehicle.

...

Random google search for scramjet shuttle replacement gives me this...

http://www.csa.com/hottopics/newshuttle/overview.php Which mentions a shuttle replacement named the X-33.

[Lightning]

Some radical ideas of mine...

1. I'm sure there is some way to reverse the gravity of something against the earth?

316188[/snapback]

When anti-gravitons are discovered, we'll let you know.

316207[/snapback]

They kinda were, watch the first episode of SDF Macross TV.

[Sundown]

Actually, the pen was freely developed by an independent company.

And was developed to solve major problems with penccil shavings and eraser turds in a 0G environment.

Rather than staying in teh sharpener, or falling politely to the floor, they drift through the air, until they A. are inhaled, B. get stuck in someone's sye, or C. drift into electrical parts and cause a short.

Wow, I was wondering about exactly that, thinking, "wouldn't eraser crumbs pose a problem?" especially having heard that crud doesn't fall nicely to the floor waiting to be swept away in 0-g, and thus compartments have to be kept pristine. I've heard jokes about Nasa's pen, but never thought it was developed to avoid just that problem you'd have with pencils.

The simple fact is that spacetravel is STILL the safest method of travel available to man.  Take 100 random people on their trips to work in the morning, and compare that to the first 100 STS flights. There was only ONE accident out of the first 100 shuttle trips.... NINETY NINE PERCENT EFFECTIVE. That's not to say some missions weren't aborted because of some reason or another, but in those cases no one was injured. Compared to the 100 car trips? You're bound to have at least 15 automobile accidents, if not more... some injuries, possibly fatal. Even if you compared fatality rates, that's still a damned impressive record.

Err, these figures have to be off. If 15 out of every 100 commuters get involved in an accident daily, we would be reduced to 10% of commuter cars not having some sort of accident damage within two weeks. One single week if we're actually counting their return trips home. And since the death rate of any accident is about 1 in 160, within three months, half the commuters would be dead.

I, making two trips a day, should also be dead several times over since I've been driving.

Looked around on the net and found that the chances of being killed in a auto-mobile accident is 1 in 5,000. The chances of being in an accident are a few times higher, but they don't begin to approach 1 in 100. Chances of dying in a plane crash is 1 in 400,000. On a train, similar statistics. So turns out that space travel is one of the most dangerous, not the safest.

-Al

Edited August 1, 2005 by Sundown

[Zentrandude]

what about those mechanical pencils only thing you need to worry is the eraser but they could just take them off before lift off.

Anyways the shuttle is still good but no comment on the fuel tank issue not like nasa going to look at MW for help.

[The Nighthawk]

Dangerous it may be, but one of the big problems with the space program is its big fat public profile. Back in the late 40s and through much of the Cold War we killed untold dozens of test pilots trying out rocket planes, VTOLs, lifting bodies, what have you. Sometimes planes were having static engine tests on the ground and just blew up, killing the people working on them. But no one made a big stink about it and there wasn't this public outcry we see when NASA has a boo-boo, partially because there's a different perception in the public when it comes to the space program. The public expects it to be better, to be safe, to be perfect every time. When it isn't, the media jumps on it and people on both sides of the aisle start going "Harrumph" and moaning about what a waste it is, and the public, being sheep for the most part, play along. I guess what bugs me is, when 1,000 people die wearing Army uniforms, there's a bit of an outcry but a lot of people just say, "Oh well, that's war, they signed up, and that's just what happens." Seven people in NASA jumpsuits die, and it's like the entire program should be scrapped. They volunteered too. They knew the risks involved and faced those risks bravely. And that fact they did it in the name of science and humanity, in a peaceful mission, I think, means more than getting car-bombed in a pointless battle over oil and petty revenge. Not saying the sacrifice of our soldiers isn't noble, just that it's ultimately pointless and we have better things we could be doing.

Edited August 1, 2005 by The Nighthawk

[Zentrandude]

Instead of blasting a rocket... how about using imploding force?

Larry Niven and Jerry Pournelle wrote a book called Footfall where space elephants attack the Earth ( Yeah I know, nutty plot) Anyway the humans on Earth launch and attack cruiser thats build on like a giant iron plate of metal. And underneath it they detonate nukes in progressive stages to get the thing into orbit.

Obviously they were in a dire situation and the environmental fallout was less of a worry due to the killer elephants, however I read somewhere that the theory in practice was sound. That you wouldn't have to worry about weight at all. You just keeping detonating nukes under that plate.

Maybe one of the guys who read the book more recently than me, or one of the guys who is better at math/physics could tell me Niven and Pournelle were full of it, or if that was a viable though toxic way into space.

Also, the magnetic rail gun theory ( yeah yeah its Metal Gear Solid I know) Not for human transport, but if NASA developed a large rail gun, couldn't they just fire supplies and equipment into space for later pickup? Seems to me, the biggest problem with more frequent space travel besides the delivery vehicles is the fuel/weight/fuel effieciency issue.

316279[/snapback]

I remember theres a guy in alaska doing that but with smaller conical shaped objects and a laser from the old star war project.

[JB0]

what about those mechanical pencils only thing you need to worry is the eraser but they could just take them off before lift off.

As a devout mechanical pencil user, I have to say...

They still leave graphite powder behind.

And you can break the lead fairly easily.

So you've eliminated wood shavings and eraser turds, but not all debris.

The ballpoint pen is the only truly clean writing utensil that I know of.

And it has to be pressurized to work in space.

Fisher's "space pen" went a few steps beyond what was needed for the task by making the ink so versatile. But that may have been a side effect of making it not spray out when the ball wasn't rolling.

Instead of blasting a rocket... how about using imploding force?

Larry Niven and Jerry Pournelle wrote a book called Footfall where space elephants attack the Earth ( Yeah I know, nutty plot) Anyway the humans on Earth launch and attack cruiser thats build on like a giant iron plate of metal. And underneath it they detonate nukes in progressive stages to get the thing into orbit.

Obviously they were in a dire situation and the environmental fallout was less of a worry due to the killer elephants, however I read somewhere that the theory in practice was sound. That you wouldn't have to worry about weight at all. You just keeping detonating nukes under that plate.

Maybe one of the guys who read the book more recently than me, or one of the guys who is better at math/physics could tell me Niven and Pournelle were full of it, or if that was a viable though toxic way into space.

It's viable, and not even that dirty.

Not very efficient, though.

The third law of motion doesn't care whare the force comes from, just that it exists. The US government was actually looking into atomic rockets before nukes became a bad thing.

Change the nukes out for chemical explosives and confine them in a chamber to focus and direct the force of the explosion and you've got... a rocket engine.

Fallout is really only an issue if you're blowing the bombs up on the ground, as the vast majority of it is irradiated dirt.

The amount of material the bomb itself sheds is negligible. Moreso if you're using fusion instead of fission.

An airburst with a fusion weapon can be considered clean.

Also, the magnetic rail gun theory ( yeah yeah its Metal Gear Solid I know)

*sighs*

Metal Gear Solid did NOT invent the rail gun.

And hell, Rex's rail gun wasn't even capable of intercontinental firing, if you paid attention to the game. Much less orbital insertion.

You airdrop a Metal Gear into enemy territory, or march it in from a neighboring US-controlled facility, and fire the rail gun from there.

The strategy hasn't changed with time, only the delivery mechanism. The first 3 Metal Gears* fired conventional missiles with rocket engines, Rex fired thrusterless warheads with a radar-absorbant shell. That was the only signifigant diffrence.

*GBColor's Metal Gear: Ghost Babel{known in the USA as Metal Gear Solid, because Konami likes to confuse people} added another mech to the family tree between the Mk2 and Rex.

Not for human transport, but if NASA developed a large rail gun, couldn't they just fire supplies and equipment into space for later pickup? Seems to me, the biggest problem with more frequent space travel besides the delivery vehicles is the fuel/weight/fuel effieciency issue.

A. Rail guns requires MASSIVE amounts of electricity.

B. You'll quite likely fry any electronics you try to send up with a rail gun due to the EMP generated in the barrel.

[JELEINEN]

Instead of blasting a rocket... how about using imploding force?

Larry Niven and Jerry Pournelle wrote a book called Footfall where space elephants attack the Earth ( Yeah I know, nutty plot) Anyway the humans on Earth launch and attack cruiser thats build on like a giant iron plate of metal. And underneath it they detonate nukes in progressive stages to get the thing into orbit.

Obviously they were in a dire situation and the environmental fallout was less of a worry due to the killer elephants, however I read somewhere that the theory in practice was sound. That you wouldn't have to worry about weight at all. You just keeping detonating nukes under that plate.

Maybe one of the guys who read the book more recently than me, or one of the guys who is better at math/physics could tell me Niven and Pournelle were full of it, or if that was a viable though toxic way into space.

It's viable, and not even that dirty.

Not very efficient, though.

The third law of motion doesn't care whare the force comes from, just that it exists. The US government was actually looking into atomic rockets before nukes became a bad thing.

Change the nukes out for chemical explosives and confine them in a chamber to focus and direct the force of the explosion and you've got... a rocket engine.

Fallout is really only an issue if you're blowing the bombs up on the ground, as the vast majority of it is irradiated dirt.

The amount of material the bomb itself sheds is negligible. Moreso if you're using fusion instead of fission.

An airburst with a fusion weapon can be considered clean.

That's project Orion that I linked to earlier. Actually, it's a very efficient form of space drive (the numbers are listed in my link); it's just not something you'd want to use to lift off from a planet with. Build it in orbit and you've got one hell of a ship for exploring the solar system with. That site has stats for other types of drives as well. It's a lot of fun, really.

[Druna Skass]

The third law of motion doesn't care whare the force comes from, just that it exists.  The US government was actually looking into atomic rockets before nukes became a bad thing.

I bet that's where the guys behind SEED got the idea for GENESIS.

[RFT]

jumping in...

A. Rail guns requires MASSIVE amounts of electricity.

rockets require MASSIVE amounts of fuel- getting into orbit is always going to require a lot of energy- doing it electrically may very well be safer than using explosive chemicals.

B. You'll quite likely fry any electronics you try to send up with a rail gun due to the EMP generated in the barrel.

That's an interesting point- one I'd not really thought about when thinking of rail-based launch systems. that sounds like a surmountable problem though.

on the subject of the fate of buran and energia- the one in gorky park is just a mockup- it looks like the only spaceworthy craft was destroyed in 2002 when its hangar roof collapsed.

Link

[Lindem Herz]

on the subject of the fate of buran and energia- the one in gorky park is just a mockup- it looks like the  only spaceworthy craft was destroyed in 2002 when its hangar roof collapsed.

Link

316444[/snapback]

Sad but true (look at the pic) - then again, it probably wasn't spaceworthy anymore, lack of maintenance and all that stuff since the early 90s.

There is another one, though. Ptichka, article 1.02 (Buran was 1.01), that was almost completed (in the upper 90% as far as I remember, gotta hunt the number) at the time of cancelation. There were also three more Buran class shuttles, articles 2.01, 2.02 and 2.03 (yes, they were updating and improving the design, even before the first flight ) in various states of completion, from 60 to 10%.

Their fates? Articles 2, sold as scrap or sold on ebay. Ptichka, parked somewhere in Baikonur (yup, at least Buran got a hangar). Test articles, most of them destroyed/sold as scrap excepting the structural that's in Gorky park, the engeneering mock up that's at Baikonour, and the atmospheric flight tester that toured Australia in 2001/2002, after THAT company went down it ended up in Bahrain somehow, where it was found and bought by the Sinsheim Auto & Technik Museum. Hasn't been ferried to Germany yet, though. -___-U

Frankly talking, I don't care too much about the shuttles. Yes, they are wonderful pieces of machinery and beautiful airframes (though I like the look of the pods on the Columbia class better), but they are limited space craft hampered by a lot of compromises (some of them, the USAF ones, taking into account the enviroment of the then USSR, weren't even necesary in Buran) - it's the Energiya booster what I'd like to see salvaged, updated and flown again. Damn promising design, so ahead of it's time that even unmodified would still cover the requirements of the new boosters of NOW, and probably will still be covering them in twenty years.

[JB0]

jumping in...

A. Rail guns requires MASSIVE amounts of electricity.

rockets require MASSIVE amounts of fuel- getting into orbit is always going to require a lot of energy- doing it electrically may very well be safer than using explosive chemicals.

Its easier to generate a flaming explosion than electricity, though.

And I don't believe railguns are really very efficient devices(may be mistaken).

B. You'll quite likely fry any electronics you try to send up with a rail gun due to the EMP generated in the barrel.

That's an interesting point- one I'd not really thought about when thinking of rail-based launch systems. that sounds like a surmountable problem though.

It may be surmountable.

But you add a lot of mass for the EM shielding.

Which in turn adds a lot of energy needed for an already power-hungry system.

on the subject of the fate of buran and energia- the one in gorky park is just a mockup- it looks like the  only spaceworthy craft was destroyed in 2002 when its hangar roof collapsed.

Link

316444[/snapback]

:'(

[JELEINEN]

And I don't believe railguns are really very efficient devices(may be mistaken).

I think this is correct. I recall reading that to get a decent payload into space from Earth's gravity, would require a ridiculously long track (we're talking thousands of miles long). I have heard that putting one on the moon would be very practical and a likely development if we ever decided to put a permanent settlement there.

[ogami]

I have a really dumb question I wanna ask:

Before the Columbia accident, the Space Shuttle fleet flew many times and never have a problem with the fuel tank's foam... then how come suddenly the foam is a weakest link of the whole Space Shuttle program? Is the foam that weak since the first space shuttle mission?

[David Hingtgen]

In a word---yes. Foam has always broken off, but it's never caused a problem---until Columbia. Shuttles have also lost tiles on every flight, but it's never been a problem---yet.

[Zentrandude]

I have a really dumb question I wanna ask:

Before the Columbia accident, the Space Shuttle fleet flew many times and never have a problem with the fuel tank's foam... then how come suddenly the foam is a weakest link of the whole Space Shuttle program? Is the foam that weak since the first space shuttle mission?

316563[/snapback]

tv media knows how to make a mountain out of a mole hill and vice versa.

[ogami]

In a word---yes.  Foam has always broken off, but it's never caused a problem---until Columbia.  Shuttles have also lost tiles on every flight, but it's never been a problem---yet.

316584[/snapback]

wow... that's mean all the successful mission were based on luck!?!

[Kin]

Hmm... why pierce with highspeed through the atmosphere causing heat and flames? what will happen if you go as fast as the earth's turning outer diameter and drop down vertically?

Will the atmosphere bounce of the shuttle?

Edited August 2, 2005 by Kin

[David Hingtgen]

Basic transfer of energy/heat. (Very poor terms for physics will follow, but I'm pretty sure of the concept)

To send a shuttle into space, you need to use massively powerful rocket engines to accelerate it to Mach 25. To get back down, you need to bleed off all that energy it has. Best way to do that is to convert it into heat--the shuttle USES the friction of the atmosphere to bleed off the speed. No different than how your brakes slow down your car--they convert the energy of motion into heat via the friction of the brakes rubbing against the wheel/disc/drum etc. That's why brakes get hot. Shuttle doesn't have brake pads to rub against a disc, etc, so it uses its tiles to rub up against the atmosphere. Same result--lots of friction, you slow down, and parts of the vehicle get hot.

In other words--you need to basically "get rid of" all the energy you used to put it into orbit in the first place. Coming in at an angle and heating up is among the best ways to do it. If you want to come in very slowly and avoid friction, it'd take forever and a day to get back.

[Kin]

Basic transfer of energy/heat.  (Very poor terms for physics will follow, but I'm pretty sure of the concept) 

To send a shuttle into space, you need to use massively powerful rocket engines to accelerate it to Mach 25.  To get back down, you need to bleed off all that energy it has.  Best way to do that is to convert it into heat--the shuttle USES the friction of the atmosphere to bleed off the speed.  No different than how your brakes slow down your car--they convert the energy of motion into heat via the friction of the brakes rubbing against the wheel/disc/drum etc. That's why brakes get hot.  Shuttle doesn't have brake pads to rub against a disc, etc, so it uses its tiles to rub up against the atmosphere.  Same result--lots of friction, you slow down, and parts of the vehicle get hot. 

In other words--you need to basically "get rid of" all the energy you used to put it into orbit in the first place.  Coming in at an angle and heating up is among the best ways to do it.  If you want to come in very slowly and avoid friction, it'd take forever and a day to get back.

316598[/snapback]

Yes, but what if the shuttle travels in a way it just keeps hovering like above washington and fall straight vertically towards the earth? With 0 friction, how does the atmosphere (ozon) reacts with the shuttle?

[Stamen0083]

Yes,  but what if the shuttle travels  in a way it just keeps hovering like above washington and fall straight vertically towards the earth? With 0 friction, how does the atmosphere (ozon) reacts with the shuttle?

316607[/snapback]

The ozone layer has nothing to do with any interaction whatsoever, save the interactions already associated with the atmosphere, since the ozone layer is part of it.

With no friction (i.e. air completely removed), there would be nothing bleeding away the kinetic energy from the Mach 25 descent speed, and the shuttle would crash to the Earth in a spectacular fireball right on top of Washington.

The laws of physics are not easily broken. If one has excess energy one wants to get rid of, converting it into heat is easiest. There's not much else one can do.

[David Hingtgen]

That's kind of my point---with no friction, you don't slow down. If you try to come down "nicely" and not heat up----you'd be coming straight down at 17,000mph. Not good. If you want to slow down so you can actually land on a runway, you NEED to bleed off the energy somehow. If you avoided all friction on the way down, the shuttle would arrive at the runway going Mach 25 with 2 seconds to go...

Also--you can't really "hover" quite like that and come straight down. The Earth is rotating at about 1,000mph. Always have to take that into account. You have to go 25,000mph just to escape gravity. AFAIK a shuttle actually controls its altitude by its speed. Speed and orbit are utterly related. It's not like a plane. You can't simply "push up" on something in orbit and have it stay there--you will need to adjust its SPEED or it will come back down to its previous altitude/orbit. Conversely, if you change its speed, you will change its altitude. I have never really understood it, as it is literally rocket science and LOTS of math.

[Kin]

Yes,  but what if the shuttle travels  in a way it just keeps hovering like above washington and fall straight vertically towards the earth? With 0 friction, how does the atmosphere (ozon) reacts with the shuttle?

316607[/snapback]

The ozone layer has nothing to do with any interaction whatsoever, save the interactions already associated with the atmosphere, since the ozone layer is part of it.

With no friction (i.e. air completely removed), there would be nothing bleeding away the kinetic energy from the Mach 25 descent speed, and the shuttle would crash to the Earth in a spectacular fireball right on top of Washington.

The laws of physics are not easily broken. If one has excess energy one wants to get rid of, converting it into heat is easiest. There's not much else one can do.

316620[/snapback]

So... there's not enough rocketpower to slow down the shuttle to a steady halt above some place on earth? ..it kinda sucks If I think about the future of space aviation.. many crashes will occur while soaring through the atmosphere.

Edited August 2, 2005 by Kin

[Stamen0083]

EDIT: I'm totally off my rocker!

So... there's not enough rocketpower to slow down the shuttle to a steady halt above some place on earth?

If that much power is so readily available, launching and recovering spacecrafts wouldn't be so complicated. The short answer is no, there is not.

Edited August 3, 2005 by Stamen0083

[David Hingtgen]

If you took a lot of fuel up with you, you could burn it just before re-entry and slow down a LOT. The shuttle has only enough fuel remaining in orbit to slow down from Mach 25 to about Mach 22. To slow from Mach 22 to Mach 0.2 or so, it uses the atmosphere.

But taking up that fuel with you would mean you have no weight/room for any sort of payload. You'd go up into space, do nothing, burn your fuel in the retro-rockets to slow down, and come home. Kinda pointless.

It's not the power of the rocket, it's the fuel and economics, and how it relates to payload.

Edited August 2, 2005 by David Hingtgen

[Stamen0083]

For more information on landing a spacecraft:

http://www.aerospaceweb.org/question/spacecraft/q0218.shtml

And on orbital speeds:

http://www.aerospaceweb.org/question/spacecraft/q0164.shtml

[wwwmwww]

If you took a lot of fuel up with you, you could burn it just before re-entry and slow down a LOT.   The shuttle has only enough fuel remaining in orbit to slow down from Mach 25 to about Mach 22.  To slow from Mach 22 to Mach 0.2 or so, it uses the atmosphere.  

But taking up that fuel with you would mean you have no weight/room for any sort of payload.  You'd go up into space, do nothing, burn your fuel in the retro-rockets to slow down, and come home.   Kinda pointless.

It's not the power of the rocket, it's the fuel and economics, and how it relates to payload.

316633[/snapback]

I'm not sure it's that simple. Disregard fuel, economics, and payload assume you did have enough thrust to slow from Mach 25 to 0 onboard. As soon as you start to slow down you start to fall out of orbit. I think the shuttle would hit the atmosphere anyways well before it lost all it's orbital speed. Also keep it mind that while you are falling out of orbit you are accelerating in the downward direction due to gravity. If you were far enough above the atmosphere such that you could lose all your orbital speed you'd still be falling strait down with alot of speed when you did hit the atmosphere. Maybe if you had twice as much thrust needed to come to a stop on board you could direct half of it in a forward direction till you lost all your orbital speed and used the other half directed down to control your descent rate. It'd probably take you twice as much fuel to get down as it did to get up though.

The part I'm not as clear on is this. Yes you have to convert all the momentum to heat in the atmosphere to slow down and loose that enegry before you touch down but I'm not sure how much leeway they have in just how slowly they go about slowing down. I think they can take the whole process much slower and maybe not generate near as much heat however I think the problem becames that if you take it too slowly there is heat applied to the tiles for long enough that the heat can eventually make it through the tiles themselves even though the actual heat on the outside surface is much less. If you were to actively cool the inner surface of the tiles maybe you could come in real slow and take a day to dissipate all that energy.

Just a thought,

Carl

Edited August 3, 2005 by wwwmwww

[JB0]

In a word---yes.  Foam has always broken off, but it's never caused a problem---until Columbia.  Shuttles have also lost tiles on every flight, but it's never been a problem---yet.

316584[/snapback]

wow... that's mean all the successful mission were based on luck!?!

316588[/snapback]

Precisely.

Or from another PoV, the failure of the Columbia was due to luck.

Foam doesn't USUALLY break off in such a way that it collides with the RCC panels.

It was pr'ly a 1/1000 chance. And it just happened that the crew of the Columbia got a bad roll.

Yes,  but what if the shuttle travels  in a way it just keeps hovering like above washington and fall straight vertically towards the earth? With 0 friction, how does the atmosphere (ozon) reacts with the shuttle?

316607[/snapback]

0 friction is impossible unless you're holding still.

A drop "straight down" incurs MORE friction than an angled one, as you hit the denser parts of the atmosphere while going faster. And you burn up.

As was stated above, it's simply not feasable to carry enough fuel up to bring you down at a lesisurely mach 2, slowing to near-0 as you hit the ground.

...

Well, maybe if you were using Saturn Vs for orbital missions it'd be workable.

But the Saturn V is the largest rocket ever made. And carries a similarly large price tag.

On the upside, you can put a space station up in one flight instead of a dozen.

Or send 3 guys to the moon.

[VF-19]

One tiny problem with building a rail gun on the Great Wall of China. It isn't straight... That and China might have a tiny problem with having a rail gun on its wall.

Like I say to my friends and family regarding the Columbia accident. Beyond a certain point during launch or re-entry, if anything goes wrong, you're automatically screwed.

[JB0]

Hate to bring up a movie again, but in that movie The Core, didn't the scientist develop a way to use the heat into a way to reinforce the shielding?

There was this drill vehicle, and apparently it was powered by heat outside the vehicle, and the deeper it dug, the heat was somehow used to reinforce the shielding on the drill bit section.

For the techs in here, is that even theorectically possible? Using the heat and transferring it to some kind of shielding? I don't know much about reactive armor on tanks, but maybe the similar principle of harnessing heat to counteract heat. (Yes I know its a shuttle, not a tank taking an anti tank missile across the side...) 

The very mention of this movie in any sort of serious discussion makes me cry.

Brief rule of thumb: anything you saw in that movie may be discarded as absurd, comical, and impossible.

More descriptive answer:

Using heat to generate power as The Core depicted it is not possible.

It may not have registered on you, but they had what is known as a perpetual motion machine. If it WAS possible, all of our energy problems would be gone with a single well-placed chunk of flubber in the mantle. A totally source of power that will last as long as the Earth.

In reality, you CAN use heat to generate electrical energy, but you have to have a temperature differential, IE: a not-hot place. This doesn't exist during re-entry except inside the cabin, which you're trying NOT to heat up too badly. That makes it unallowed for this task, as you WILL transfer heat to the not-hot place in the process of generating current.

Besides that, we have no form of energy shielding, be it a force field or just tje strength amplification technology depicted in The Core.

Reactive armor is a quite simple affair. There's an explosive plate on the outside of the armor. When a projectile hits the armor, it blows up.

Armor-piercing explosives use a carefully designed explosive(known as a shaped charge) to make a "blowtorch" focused on the armor. The explosion from the reactive armor plate disrupts the blowtorch and prevents it from burning through anything.

As for the railgun, build it along the top wall of the Great Wall Of China, thats a hell of alot of track right there.

Not enough power, in addition to the non-linear arguments in the above posts.

And just send food, clothing, medicine, luxury items, etc into space with the railgun.  And if you miss, its just Cheeze Its and KoolAid packets.  Its like moving from place to place, you put all the regular stuff in the moving van, but you keep your tv and dvd player and other fragiles in your own POV during the move.

Except that in your comparison, the moving van isn't an unguided projectile hurtling along at mach 25 when it needs to be maneuvered into orbit and around satellites.

I know the energy needed to power a railgun would be immense, but thats power used on the surface, not power/fuel needed to be strapped onto the shuttle, thus increasing its weight.

It's still an utterly immense power drain. We're talking a nuclear power plant dedicated SOLELY to lobbing projectiles at satellites(which the chinese would very likely use it for).

[Lynx7725]

As for the railgun, build it along the top wall of the Great Wall Of China, thats a hell of alot of track right there. And just send food, clothing, medicine, luxury items, etc into space with the railgun.  And if you miss, its just Cheeze Its and KoolAid packets.

316702[/snapback]

Err. The Great Wall of China is more likely to shatter from the repeated shockwaves from the rail breaching the sound barrier. Remember the Great Wall is not built with modern construction techniques, and parts of the Wall is actually crumbling to the extent where tourists are being barred from them.

It's better to build a dedicated railgun in the desert somewhere.

And, "its just Cheeze Its and KoolAid packets"... except, for efficiency, we would be shooting tons of Cheeze Its and KoolAid per shot, and last I check, a ton of KoolAid is still a ton. Penetration power may differ, but one ton moving at Mach 25 is going to leave a nice dent on anything it hits... provided the target survives the impact.

[David Hingtgen]

You can't "slowly" come down. Basically---To stay in orbit, you have to go fast. If you slow down a LOT, then you'll come down FAST. Which of course, "friction from dropping straight down" is just as bad as "friction from a 40 degree angle of attack".

There is a narrow band of re-entry angles where it is feasible. Too fast/steep, you'll burn up even worse, too slow/shallow, you won't slow down enough and will bounce back up into the atmosphere.

Basically--the shuttle comes down the only way it can. A certain rate, at a certain angle. If you try to slow down a LOT prior to re-entry, you will simply DROP through the atmosphere and burn up due to hurtling downwards through the atmosphere, as opposed to burning up due to hurlting forwards through the atmosphere. The shuttle comes down at just the right angle that it can bleed off speed/energy at just the rate that it can withstand the heat. Other angles are either too hot, or won't bleed off the speed.

Now, things like the Apollo capsules etc. do slow down a lot in orbit, but then come down FAST, almost vertically compared to shuttle. But that's because they're one-way trips, and cannot be reused. They get REALLY hot and vaporize most of their heat shield--because it's a one-time sacrificial heat shield. The shuttle is designed to survive re-entry and not vaporize its bottom half every flight. Thus, it has to take a more shallow approach than a Mercury/Gemini/Apollo re-entry.

[Lynx7725]

There is a narrow band of re-entry angles where it is feasible.  Too fast/steep, you'll burn up even worse, too slow/shallow, you won't slow down enough and will bounce back up into the atmosphere. 

316742[/snapback]

So, if you screw up on re-entry, you either burn up in a fireball, or you freeze when your shuttle skips off into the Big Black. Either way, it's a risky business, and having only 2 shuttle failures is actually indicative of the professionism at NASA.

The issue still stands though; the shuttle design is starting to throw up more problems than solutions. It's really time for an overhaul of the whole system.