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Posted: 12/25/2005 5:43:49 PM EDT
We've got to develop an economical aerospace vehicle to get us into space!

What's it going to be...

A Shuttle-derived disposable rocket and Apollo-type capsule?

A Hypersonic transatmospheric aircraft?

A Two-Stage-To-Orbit carrier aircraft/orbital vehicle?

Something else?
Link Posted: 12/25/2005 5:48:05 PM EDT
Whatever they come up with,it better have a more reliable DGRS (Door Gunner Restraint System)The last one failed horribly.
Link Posted: 12/25/2005 5:48:42 PM EDT
Saturn V seemed to work wonders so long as you didn't drop oxygen tanks on concrete.....
Link Posted: 12/25/2005 5:50:47 PM EDT
Space elevator

Link Posted: 12/25/2005 5:55:38 PM EDT
"thinking is the best way to travel"
Link Posted: 12/25/2005 6:03:00 PM EDT

Originally Posted By ARDunstan:
Space elevator

www.enterprisemission.com/images_v2/Iapetus5/Space_elevator_structural_d.jpg


Imagine how heavy that cable would be?
Link Posted: 12/25/2005 6:11:00 PM EDT

Originally Posted By Zakk_Wylde_470:
Saturn V seemed to work wonders so long as you didn't drop oxygen tanks on concrete.....



Rockets?

This is the Twenty-First Century. Can't we do better than that?

Rockets tend to 'splode occasionally...
Link Posted: 12/25/2005 6:12:26 PM EDT

Originally Posted By AyeGuy:

Originally Posted By Zakk_Wylde_470:
Saturn V seemed to work wonders so long as you didn't drop oxygen tanks on concrete.....



Rockets?

This is the Twenty-First Century. Can't we do better than that?

Rockets tend to 'splode occasionally...



How many Saturn V rockets exploded in an unintended manor? If it aint broke, don't fix it.
Link Posted: 12/25/2005 6:16:11 PM EDT

Originally Posted By Zakk_Wylde_470:

Originally Posted By AyeGuy:

Originally Posted By Zakk_Wylde_470:
Saturn V seemed to work wonders so long as you didn't drop oxygen tanks on concrete.....



Rockets?

This is the Twenty-First Century. Can't we do better than that?

Rockets tend to 'splode occasionally...



How many Saturn V rockets exploded in an unintended manor? If it aint broke, don't fix it.




Well we didnt use enough Saturn 5s to get near "mean time between failure". We launched way more shuttles before one failed.
Link Posted: 12/25/2005 6:17:46 PM EDT
Project Orion.....


or its woosy brother NERVA
Link Posted: 12/25/2005 6:31:16 PM EDT
Any system is only as good as the quality put into it.

The big problem at NASA is that the current management mentallity is that theastronauts are expendable and that accidents are going to happen. Enviromental concern are more important thant using the proper materials to build a dependable ship.

If the current management is in charge, any project will be overbudget, long term, and dangerous to fly. It seems almost that they don't want the US Space program to be the world leaders.

Damn those liberals.
Link Posted: 12/25/2005 6:42:04 PM EDT
A two-stage-to-orbit system should be easilby reachable.

Take a large carrier aircraft capable of high mach numbers, and carried on top a small rocket-propelled vehicle (a lifting-body for personnel and a cylindrical rocket for cargo).

This configuration has been studied to death since the 1950s. It will work! Somone somewhere just has to get around to finally putting the hardware together. No exotic technologies are needed; we have all the tech on the shelf right now!
Link Posted: 12/25/2005 6:46:03 PM EDT
Link Posted: 12/25/2005 6:47:53 PM EDT

Originally Posted By 71-Hour_Achmed:

Originally Posted By ARDunstan:
Space elevator

www.enterprisemission.com/images_v2/Iapetus5/Space_elevator_structural_d.jpg


+1



+2
Link Posted: 12/25/2005 6:50:14 PM EDT
[Last Edit: 12/25/2005 6:52:48 PM EDT by ElCamino]
Repulsorlift + ion thrusters till you get out of the planet's gravity well, then hyperdrive once you're clear.

ETA: Just keep in mind that traveling through hyperspace ain't like dusting crops, boy. Without precise calculations you could fly right through a star or bounce too close to a supernova, and that would end your trip real quick, wouldn’t it?
Link Posted: 12/25/2005 7:07:05 PM EDT
Link Posted: 12/25/2005 7:08:07 PM EDT
[Last Edit: 12/25/2005 7:56:45 PM EDT by DukeSnookems]
These discussions always bug me because the armchair astronauts always come out, take a dump on NASA without any clue as to what they are talking about.

Let's debunk a couple of things first:


Myth: The Space Elevator will be the silver bullet
Reality: People love to quote this because it sounds cool, concept is easy to understand, and it makes them sound smart. The reality is that there's no such thing as a free lunch. It's not as simple as sending something up on a string. First, that "string" depends on the development of carbon nanotubes over 60,000 miles long and we've yet to make any single wall nanotubes more than a few cm. Nothing else is strong enough. Secondly, again, there's no such thing as a free lunch. Think back to your physics classes and remember the conservation of angular momentum? That satellite that climbed up 22,000 miles (if it is going into geosynchronous orbit) has a lot more energy than it did when it was on the ground because it is now travelling at GS orbital speed (or else it would fall down), that energy has to come from somewhere. It draws it from the anchor on the other end of the tether, so you can't just keep sending up satellites. The anchor needs to be "recharged" with rockets, by sending objects down, or other means or it will go too slow and fall to the earth itself. That's one thing people always overlook. Also unless we capture an asteroid that just happens to be travelling as we need it (don't bet on it), that anchor has got to be flown up there with and it will need to be heavy, this is no small task. That doesn't mean it's not going to happen, it's just not as simple as people think (where are the flying cars?).

Myth: A private company (Scaled Composites) put a man in space for a fraction of what it would cost NASA, who needs NASA?!
Reality: I'm a big fan of Burt Rutan, the man is a genius. But comparing SpaceShipOne to any kind of orbiting vehicle is like comparing an airsoft gun to a howitzer. SpaceShipOne put a man into "space" by sending him 62 miles straight up. To do this, it only needed to be able to reach speeds of 2000 mph. This a far cry from what you need to put something into *orbit*. Low Earth Orbit (LEO) requires a speed of over 16,000mph. That's over 8 times faster than a 5.56 bullet! The shuttle does that while weighing roughly (varies with mission) 200,000 lbs !! As you guys should know from ballistics, every time you double your velocity, you need to put in at least 4x more energy to do it. Do the math and you will see that Scaled Composites would need something 2,400 x more powerful to do what the shuttle does. That's the quick and dirty talk just regarding the power required, in reality it becomes much more complicated making an orbital vehicle that is habitable, mission adaptable, able to survive re-entry from orbital velocities, etc... Will it happen one day? Most likely, but it's not as simple as everyone believes and don't expect it anytime soon (flying cars here too). You're not dealing with cars, or microprocessors here, there's no "Moore's Law" for propulsion systems.

As far as the Saturn V, it is designed to send a small object spacecraft to the *moon,* with the way its stages were designed, it's not something you want to put satellites into orbit.

The most promising technology was the SSTO (Single Stage To orbit) program which I had a small role in. They couldn't get the structure light enough (mostly the fuel tanks) to work so it was scrapped, at least that was the official reason.

There's a million other things on the table. Scramjet "boosters" look promising, I think that was the 2 stage vehicle you were thinking of. They also got some other really far off stuff on the table. For interplanetary travel, I was lucky enough to hang out with Chang-Diaz when he was working on an Ion propulsion system. It was pretty cool, we had to call Houston lighting and power when we turned it on because it drew so much electricity
Link Posted: 12/25/2005 7:10:05 PM EDT
Big fuckin rubber band
Link Posted: 12/25/2005 7:10:10 PM EDT

Originally Posted By ElCamino:
Repulsorlift + ion thrusters till you get out of the planet's gravity well, then hyperdrive once you're clear.




Ion drives at the most put out about 1/10,000g, so they are useless in lifting off a planetary surface.
Link Posted: 12/25/2005 7:10:43 PM EDT
Link Posted: 12/25/2005 7:13:33 PM EDT

Originally Posted By Win_88:
Any system is only as good as the quality put into it.

The big problem at NASA is that the current management mentallity is that theastronauts are expendable and that accidents are going to happen. Enviromental concern are more important thant using the proper materials to build a dependable ship.

If the current management is in charge, any project will be overbudget, long term, and dangerous to fly. It seems almost that they don't want the US Space program to be the world leaders.

Damn those liberals.



Exactly what I meant when I said "These discussions always bug me because the armchair astronauts always come out, take a dump on NASA without any clue as to what they are talking about"
Link Posted: 12/25/2005 7:13:36 PM EDT
if we could put something really fast on a conveyor belt....
Link Posted: 12/25/2005 7:31:13 PM EDT

Originally Posted By DukeSnookems:

I was lucky enough to hang out with Chang-Diaz when he was working on an Ion propulsion system. It was pretty cool, we had to call Houston lighting and power when we turned it on because it drew so much electricity



Are you talking about VASIMIR?

I think that has already been superceeded by the Dual-Layer Plasma Thruster:

link to story
Link Posted: 12/25/2005 7:34:16 PM EDT
Link Posted: 12/25/2005 7:43:45 PM EDT

Originally Posted By AyeGuy:

Originally Posted By DukeSnookems:

I was lucky enough to hang out with Chang-Diaz when he was working on an Ion propulsion system. It was pretty cool, we had to call Houston lighting and power when we turned it on because it drew so much electricity



Are you talking about VASIMIR?

I think that has already been superceeded by the Dual-Layer Plasma Thruster:

link to story



Yep, it got scrapped. It was ~ 10 years ago when I saw it when it had copper coils, he had plans to start using superconductor coils, not sure if it made it that far.
Link Posted: 12/25/2005 8:02:40 PM EDT

Originally Posted By NoVaGator:
if we could put something really fast on a conveyor belt....



But it will only launch patty shaped objects unless Chuck Norris is driving the belt, if that was the case we could launch the whole world into space.
Link Posted: 12/25/2005 8:09:39 PM EDT
Link Posted: 12/25/2005 8:27:56 PM EDT
Link Posted: 12/25/2005 8:35:46 PM EDT

Originally Posted By AyeGuy:

Originally Posted By ElCamino:
Repulsorlift + ion thrusters till you get out of the planet's gravity well, then hyperdrive once you're clear.




Ion drives at the most put out about 1/10,000g, so they are useless in lifting off a planetary surface.



TIEs are pretty quick. Besides, most of your atmospheric flight is powered by repulsorlift.
Link Posted: 12/25/2005 8:52:34 PM EDT
anti-gravity, re-entry would be a bit smoother too.
Link Posted: 12/25/2005 9:09:42 PM EDT

Originally Posted By ar15_rifleman:
www.wvip.co.uk/images/dvd/Space1999/Space1999_Eagle.jpg


I thought those 1999 eagles where slicker than shit
Link Posted: 12/25/2005 9:11:54 PM EDT
This thread is getting Silly, which was not my intent.

The board aero engineers must be giving their brains the night off, so this is what I have to deal with...
Link Posted: 12/25/2005 9:16:04 PM EDT

Originally Posted By PinePig:
, if that was the case we could launch the whole world into space.




Uh, in case you didn't notice,... the whole world IS in space.
Link Posted: 12/25/2005 9:29:41 PM EDT
The space elevator would take its angular momentum from the earth, not the counterweight. As you lifted mass to orbit the rotation of the earth would very slightly slow down.
Link Posted: 12/25/2005 9:31:32 PM EDT

Originally Posted By twonami:

Originally Posted By ar15_rifleman:
www.wvip.co.uk/images/dvd/Space1999/Space1999_Eagle.jpg


I thought those 1999 eagles where slicker than shit



Yes, one of the few sci-fi spaceships designed around real engineering principles (sigh...)

But...what's with the windows on the BOTTOM of the command module?

The bottom is a mirror-image of the top, that's why...they just used the same mold to make both halves.

Sometimes those Brits can be real cheap bastards...make another mold, fer crissakes! Or fill-in the window cut-outs on the top mold and make another resin cast! Not too hard! Sheesh!
Link Posted: 12/25/2005 9:34:04 PM EDT
Link Posted: 12/25/2005 9:34:54 PM EDT

Originally Posted By mcgredo:
The space elevator would take its angular momentum from the earth, not the counterweight. As you lifted mass to orbit the rotation of the earth would very slightly slow down.



Well, that wouldn't do us much good, would it? Slow down the whole Earth?

By the way, the Earth used to rotate much more rapidly...the Moon has been ROBBING us of orbital momentun for some time now. 1 billion years ago the Earth rotated in 12 hours; how about that!
Link Posted: 12/25/2005 10:01:45 PM EDT
[Last Edit: 12/25/2005 10:03:05 PM EDT by BillofRights]

Originally Posted By DukeSnookems:
These discussions always bug me because the armchair astronauts always come out, take a dump on NASA without any clue as to what they are talking about.

Let's debunk a couple of things first:


Myth: A private company (Scaled Composites) put a man in space for a fraction of what it would cost NASA, who needs NASA?!
Reality: I'm a big fan of Burt Rutan, the man is a genius. But comparing SpaceShipOne to any kind of orbiting vehicle is like comparing an airsoft gun to a howitzer. SpaceShipOne put a man into "space" by sending him 62 miles straight up. To do this, it only needed to be able to reach speeds of 2000 mph. This a far cry from what you need to put something into *orbit*. Low Earth Orbit (LEO) requires a speed of over 16,000mph. That's over 8 times faster than a 5.56 bullet! The shuttle does that while weighing roughly (varies with mission) 200,000 lbs !! As you guys should know from ballistics, every time you double your velocity, you need to put in at least 4x more energy to do it. Do the math and you will see that Scaled Composites would need something 2,400 x more powerful to do what the shuttle does.




Quick correction. The highlighted area above is an incorrect assumption. Your quote about speed vs power is dependent on air resistance which drops off with altitude. For instance,for the same speed, an aircraft uses about 1/2 as much fuel at 40,000 feet as it does at sea level.

Don't be so eager to prove your point that you gloss over such obvious facts. It will work with the general public, but not with the edumicacated wisasses on this board. Obviously the shuttle has greater ability, but it is not an airsoft to howitzer comparison. More like .22 to .50 BMG.
Link Posted: 12/25/2005 10:13:22 PM EDT

Originally Posted By mcgredo:
The space elevator would take its angular momentum from the earth, not the counterweight. As you lifted mass to orbit the rotation of the earth would very slightly slow down.



If you're an engineer, draw a free body diagram of the earth, cable satellite, and anchor. You'll see that the satellite will pull on the cable like a bow and arrow. The earth's rotation will be ever so slightly slowed down. To a much greater degree, so will the anchor on the other end of the cable since the force acting on that anchor has a westward vector to it. As the payload climbs, more of the angular momentum will be supplied by the anchor. That's part of the reason why the plans are to have it over 60,000 miles out, well past geosynchronous orbit. To provide tension, mimize the westward vector, and maximize angular momentum. If it is heavy enough (like a massive asteroid), it won't be a major concern. When was the last time a large asteroid was seen approaching earth at a rate where it could be captured though?

If the cable were rigid, then the earth's rotation could provide all of the angular momentum as you said but you're not going to find any material that would be able to do it.
Link Posted: 12/25/2005 10:23:09 PM EDT
We can't have a space elevator, ever.

The muslims would blow it up
Link Posted: 12/25/2005 10:28:17 PM EDT
[Last Edit: 12/25/2005 10:32:14 PM EDT by DukeSnookems]

Originally Posted By BillofRights:

Originally Posted By DukeSnookems:
These discussions always bug me because the armchair astronauts always come out, take a dump on NASA without any clue as to what they are talking about.

Let's debunk a couple of things first:


Myth: A private company (Scaled Composites) put a man in space for a fraction of what it would cost NASA, who needs NASA?!
Reality: I'm a big fan of Burt Rutan, the man is a genius. But comparing SpaceShipOne to any kind of orbiting vehicle is like comparing an airsoft gun to a howitzer. SpaceShipOne put a man into "space" by sending him 62 miles straight up. To do this, it only needed to be able to reach speeds of 2000 mph. This a far cry from what you need to put something into *orbit*. Low Earth Orbit (LEO) requires a speed of over 16,000mph. That's over 8 times faster than a 5.56 bullet! The shuttle does that while weighing roughly (varies with mission) 200,000 lbs !! As you guys should know from ballistics, every time you double your velocity, you need to put in at least 4x more energy to do it. Do the math and you will see that Scaled Composites would need something 2,400 x more powerful to do what the shuttle does.




Quick correction. The highlighted area above is an incorrect assumption. Your quote about speed vs power is dependent on air resistance which drops off with altitude. For instance,for the same speed, an aircraft uses about 1/2 as much fuel at 40,000 feet as it does at sea level.

Don't be so eager to prove your point that you gloss over such obvious facts. It will work with the general public, but not with the edumicacated wisasses on this board. Obviously the shuttle has greater ability, but it is not an airsoft to howitzer comparison. More like .22 to .50 BMG.



Another ARFCOM Einstein

Physics refresher:
Kinetic Energy = 1/2 X Mass X Velocity^2

Notice how velocity is squared? Therefore if you double that velocity, what happens to your KE? That's right, it's multiplied by four, easy enough to follow? It has absolutely NOTHING to do with air resistance. If you account for efficiencies, that just adds to my point that things get exponentially more complicated as you increase your speed, but for the sake of simplicity (wasn't simple enough for you I suppose), I only approached it only as an energy equation.
Link Posted: 12/25/2005 10:32:35 PM EDT

Originally Posted By mcgredo:
The space elevator would take its angular momentum from the earth, not the counterweight. As you lifted mass to orbit the rotation of the earth would very slightly slow down.



Finally. Thanks for mentioning this. (though I could use longer days.)
Link Posted: 12/26/2005 7:13:53 AM EDT
[Last Edit: 12/26/2005 7:19:15 AM EDT by cmjohnson]
Link Posted: 12/26/2005 7:28:11 AM EDT
DAmn, we need a Zed PM like in Stargate!
Link Posted: 12/26/2005 9:51:41 AM EDT
Looks like we are going to be stock with another Capsule. Like Apollo but 1.5X bigger.

new moon rocket designs here
Link Posted: 12/26/2005 9:54:58 AM EDT

Originally Posted By SC-Texas:
DAmn, we need a Zed PM like in Stargate!



damn canadians
Link Posted: 12/27/2005 5:03:52 PM EDT

Originally Posted By DukeSnookems:

Originally Posted By Win_88:
Any system is only as good as the quality put into it.

The big problem at NASA is that the current management mentallity is that theastronauts are expendable and that accidents are going to happen. Enviromental concern are more important thant using the proper materials to build a dependable ship.

If the current management is in charge, any project will be overbudget, long term, and dangerous to fly. It seems almost that they don't want the US Space program to be the world leaders.

Damn those liberals.



Exactly what I meant when I said "These discussions always bug me because the armchair astronauts always come out, take a dump on NASA without any clue as to what they are talking about"



Everytime that a topic is involving NASA, or Shuttle replacement the same arguments come up.
If you had read the last topics on NASA, you would have read the same stories and FACTS about NASA and its management. After the Shuttle Discovery launch of STS 114 back in July 2005 and the damage that it had from every bit of debris including a bird.

A topic on AR15 was about both NASA(management) and the future of the shuttle program. This topic included quotes of NASA manager showing little concerns of the crew and having a CYA moment infront of the press.
The whole tile problem was the result of NASA switching the tile adhesive(with Freon) to an enviromentally friendly adhesive. The new adhesive is fragile and wont hold as the original.
This was a known fact at NASA, but pleasing the enviromentalist was more important.

This NASA is not the same NASA as the one I remember from the 60's. That NASA Management cared about the astronauts. They corrected errors in designs for safety of the crew.

The current NASA managemnet is no better than AMTRACK. Both suck, Both dont give a crap about vehicle design or safety. Both rather go about showing how enviromentally friendly they are by changing to envimentally friendly products and vehicles. Both don't give a crap about the crews or passengers.

The NASA management of the 60's got things done. They didn't take or promise to take man to the moon for 40 years. they did it in less than ten. This NASA has been making promises for 35 years.

Ask yourself these questions:
Have we returned man to the moon?(Promised for the 80's)
Do we have a permanent base (Colony)on the moon? (promised for the 80's)
Have we had a man landing on Mars?( promised for 1990's)
Do we have a permanent space station for mission launch in orbit?(promised for the late 70's)
Do we have a long mission vehicle?(promissed for 80's)

All were NASA promises.

NASA promises a man mission to the moon by 2020. Don't hold your breath...

The Chinese will be there in the next 5-7 years. They promise to delcare the moon as Chinese territory.

I'm not an armchair astronaut. I'm one of those people who is always being disapointed by NASA.

In the furure. The Civilian Space Programs will leave NASA in the dust. NASA days are numbered. Its only a matter of time...
Link Posted: 12/27/2005 5:15:06 PM EDT
Space elevator does seem to be the best way to go now.

The only thing holding it back is securing enough good quality CN feedstock.

University of Kentucky has spun a single SWNT filliment 3 Kilometers long, it would have been longer but they ran out of feedstock (and money)

Thing is that CN also holds the key to building a SSTO spacecraft. Through it we can get lighter fuel tanks, solve the heat problems with aerospilke engines, and make stronger heat shielding materials.

With elevator or with ships, either way, improvment depends on the development of Carbon Nanotube materials.

And the solution to one is the same as the other.
Link Posted: 12/27/2005 5:36:26 PM EDT

Originally Posted By ArmdLbrl:
Space elevator does seem to be the best way to go now.

The only thing holding it back is securing enough good quality CN feedstock.

University of Kentucky has spun a single SWNT filliment 3 Kilometers long, it would have been longer but they ran out of feedstock (and money)

Thing is that CN also holds the key to building a SSTO spacecraft. Through it we can get lighter fuel tanks, solve the heat problems with aerospilke engines, and make stronger heat shielding materials.

With elevator or with ships, either way, improvment depends on the development of Carbon Nanotube materials.

And the solution to one is the same as the other.



Anything besides a cable fabed from nanotubes requires a matrix to form the part; it will have the same deficiencies as every other fiber/matrix material - interlaminar strength problems, most likely poor bearing strength, and others.

The only compelling reason to get large masses off the Earth is to build containers for self contained colonies that can head for nearby stars.

The rest of the work can be done with small machines.

Link Posted: 12/27/2005 6:19:21 PM EDT
A laser launch system would be great, if we could power it. We really need to get going on serious exploitation of nuclear power and to hell with the envirowhackos.
Link Posted: 12/27/2005 8:54:59 PM EDT
Where to begin...????

The shuttle (At it's base form) is a 1950's spacecraft flying on 1930's rocket technology.

It still takes 10's of thousands, if not 100's of thousands of people to prepare and launch it every time.

It's cost of operation, IE: the cost of putting 1lb. into orbit (LEO at that) is too expensive!

Until we can have space travel become much more like air travel. Space shall remain the domain of large corporations & governments. No one else can afford it.

Just to re-state what many have stated.......

Speed to reach L.E.O. (Low earth orbit.....Shuttle/Satilite pre-boost)............17,000mph (approx)
Speed to reach Moon/Space (or anywhere else)................................25,000mph (Approx)

In other words.... The shuttle isn't a "Space" vehicle like the Saturn V was!
You are NOT! going anywhere "Out in space" with what we are using today.


Tall Shadow
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