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Replacement for the shuttle?

LucyR

Graduate Poster
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Joined
Feb 22, 2003
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Why is NASA still screwing around with the shuttle? Why doesn't it bring back the Saturn V? I bet the latter launch vehicle would be safer, cheaper, and would carry a heavier payload. Is it a question of vested interests? Bureaucratic inertia? Really, in what way is the shuttle superior?

Any thoughts?
 
The most complex part is reusable I guess.

I find it interesting that most sattelites are still launched using conventional, expendable rockets.

As I recall there was aplan to mount the shuttle on the saturn V.

I say, get the x-33 out here, it's time has come!

Or maybe the buran can come out of hiding and show us how it's really done.

Edited to add:

Ha! buran, another excellent example (along with tu-144, tu-4, su-100, and aa-2 atol AAM) of the originality of soviet engineering!
 
The Buran was sitting under tarpaulin on a dock in Sydney being prepared for "public display" for about 3 years. Alas, the project didn't look like taking off (ha ha!) so the rusty hulk has been shipped somewhere else - San Diego? Long Beach? Somewhere that things like that end up, anyway...
 
neutrino_cannon said:

Ha! buran, another excellent example (along with tu-144, tu-4, su-100, and aa-2 atol AAM) of the originality of soviet engineering!
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Steady on, young man. There are plenty of examples of original Soviet engineering.
 
The Saturn was much much to large for most of what you need today, remember they used leftovers from the Apollo project to make Skylab. What you need today IS somethng like the X33, a good 100% reusable launch system OR at least something that doesn't rely on those huge fireworks (solid fuel rockets) to get in orbit.

There once was a plan of launching the Shuttle from an aeroplane and then going into orbit from there. The 747 would then provide much of the take off fuel. (I know they did it during the first unpowered tests). If you can't get rid of the solid fuel rockets i'll predict that the Shuttle will be terminated for good.
 
Who would like to bet on the world's biggest rail-gun being the next launch vehicle??? :)

It still seems that they are relying on trying to "muscle" their way into orbit by sheer brute strength/speed. So far this has been about the only feasible way to do it, but it was also the most expensive and resource-expensive (eg. 90+% of each multi-million-dollar Saturn vehicle was discarded and wasted in the first half-hour or so of a flight).

I strongly suspect that there are already clever designs on the drawing-board to do this better, including air-launchs as mentioned previously. I've even heard of balloon-launches - lifted to the stratosphere, dropped to gain speed, rocket on up from there (hardly new technology - someone look up Rockoon).
 
Why don´t they use the ships they made based on the UFOs that crashed at Roswell and many other places?

Uh... Because alien ships are always crashing due to radar and TV interference?

Never mind, so...
 
Ove: There once was a plan of launching the Shuttle from an aeroplane and then going into orbit from there. The 747 would then provide much of the take off fuel. (I know they did it during the first unpowered tests).
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Have you done the numbers? A reasonable orbit is an altitude of 300 to 400 miles at a speed of about 17,000 miles per hour. At most, a 747 can get the shuttle 10 miles up and 600 mph.
 
I heard somewhere (can't recall so don't ask!) that even if they wanted to revive the Saturn V they couldn't. Apparently there isn't a complete one left, only a few bits and pieces, and when they retired it someone threw away the plans!
 
I also heard that same report. I also remember that NASA refuted it.

There were never any plans to build new Saturn V’s. But there is a whole one sitting on its side displayed and Cape Kennedy.

NASA needs two different things. One small reusable craft to get people two and from orbit. The other is a BDB. (Big, dumb booster.)

The BDB need not be a Saturn V. It would only be for heavy launches. No need to base your staging on how many G’s your astronauts can take, no need for it to be as safe as possible, since it is not for lifting humans.
 
Space elevator's the way to go, much better, and it should only cost $15 billion to build.

It doesn't matter what NASA does anyway, the rest of world got sick of the US lording it over us with their space program, so now everyone's in on the act :) Someone is bound to come up with something good, whether it's Europe, China, the US or even Brazil remains to be seen.
 
American said:
How's about a really, really, REALLY big rubber band?
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How practical is this idea really?

The elastic potential energy in the stretched band is given of course by

(1/2)*kdx^2, ….1

where k is the constant of proportionality in the simple harmonic approximation, or ‘spring constant’, and dx is the change in length.

Now in the absence of non-conservative forces the potential energy would be fully converted into kinetic energy, which in turn is given by (1/2)*mv^2, where m is the mass of the projectile and v is its final velocity. We can then express the extension as

dx = v*sqrt(m/k), ….2

Now what would dx be in practice? Let us assume a spring constant of 100 N/m, a projectile mass of 1000 kg, and a required final velocity of 10 km/s (basically between orbital and escape velocity). Substituting these values into Eq. 2 gives an extension of

dx ~ 31.6 km.

If we further assume the band can stretch about 5 times its unstretched length before breaking we would have to use a band of nearly 8 km. Also note of course that this the minimum possible length, corresponding to the assumed values. I’m sure you’ll agree that this is hardly practical. Now I leave it up to you, American, to calculate the maximum acceleration imparted to our projectile and what the implications would be for any human being traveling in it….
 
Have you done the numbers? A reasonable orbit is an altitude of 300 to 400 miles at a speed of about 17,000 miles per hour. At most, a 747 can get the shuttle 10 miles up and 600 mph.
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No absolutely not, i think i got the idea from a cartoon.:D

I heard somewhere (can't recall so don't ask!) that even if they wanted to revive the Saturn V they couldn't. Apparently there isn't a complete one left, only a few bits and pieces, and when they retired it someone threw away the plans!
Click to expand...

According to the book (one of my favourites) "Apollo, the race to the moon" By Charles Murray and Catherine Cox there are actually TWO complete Saturn 5 rockets making them probably the worlds most expensive museum pieces (in Houston and at the Cape). Apparently when congress cancelled the two last Apollo missions the rockets was already buildt. There are also one complete dummy(test vehicle) in Huntsville i think.
 
Ove said:


No absolutely not, i think i got the idea from a cartoon.:D

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Moonraker!

I like the idea of a railgun. However, would you be able to control the acceleration long enough so as not to squish the astronauts?
Suppose you could build a 1000m high railgun, could you get from 0-27,000 kmh in the space of 1km without get astronaut pancakes?

I suppose you could use the railgun thingy to launch big un-squishable payloads? Or even to just give a bit of additional acceleration without having to carry the fuel?
 
Moonraker!
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No, i have had time to recall. It was a Swedish cartoon album version of (hold on to your chair) ................ Biggles.:D It was actually a quite well written story.
 
Jon_in_london said:

I like the idea of a railgun. However, would you be able to control the acceleration long enough so as not to squish the astronauts?
Suppose you could build a 1000m high railgun, could you get from 0-27,000 kmh in the space of 1km without get astronaut pancakes?

I suppose you could use the railgun thingy to launch big un-squishable payloads? Or even to just give a bit of additional acceleration without having to carry the fuel?
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Since you say "high" it seems you are thinking of launching vertically. In fact, the best thing to do would be to build your rail gun on a high plateau (above as much of the atmosphere as possible) and launch horizontally. That way, you can make it long enough to avoid pulped astronauts. A horizontal launch is more efficient anyway. In fact, if there wasn't air on the earth, they would lay Saturn 5s down on their side to touch them off...

Oh, and to do the numbers on your 1000m launcher:

a = v<sup>2</sup> / (2 * s)
= 7500*7500 / 2000
= 28125 m/s/s
= 2800g
= very squished...

--Terry.
 
Jon_in_london said:
Launching horizontally? I wonder if it would be better to go counter to the earths rotation or not?
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Go with the rotation. You get a free boost from the tangential velocity.

--Terry.
 
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