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Rail launched TSTO to Mars with just 1/10 cost of Apollo ?

Posted by: topspeed - Mon Dec 01, 2014 6:46 pm
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Rail launched TSTO to Mars with just 1/10 cost of Apollo ? 
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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Wed Feb 11, 2015 5:51 am
By launching horizontally, we provide abort options all along the way, up until abort to orbit. You do not want to eject from a vehicle traveling at 3 miles per second. While still on the track, or rail, the stack can be stopped by the same linear motor which had it moving at 350 miles per hour. Or at least slowed way, way down.

Once airborne, the orbiter can separate from the carrier wing and fly under rocket power back to the launch site. Once the orbiter has launched normally, it can either circle back and land, or land at a point further down range.

The key to making this possible is to commit to a design that is focused on one thing, and that is putting people in orbit in groups of 10 or more. Someday, there will be a bus line running to low Earth orbit, and this is the vehicle which they will base it upon.

Forget ramjets, scramjets, and other exotic motors, we will go with the tried and true rocket burning good old kerosene and liquid oxygen. At our launch altitude, rockets are close to the most efficient operating environment, which is a vacuum. The transition from aircraft to rocket plane to space craft happens in a matter of minutes, and complexity is the enemy of success.

We have to be able to get off the ground before we can talk about going to other places.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Sun Mar 01, 2015 7:26 am
As appealing as the idea of using ground-based equipment to assist in launching a spacecraft is, in reality it is extremely difficult, and not very efficient, in most cases. Because having the track bend at the end will subject the vehicle to sudden high g loads, the track must be inclined from the start, which means finding a suitable mountain, in the right location for the orbital inclination, and building the the catapult there. But even if we meet those restrictions, we still encounter so much turbulence at Mach speeds that obtaining any significant portion of orbital velocity while in the atmosphere is impossible.

But I think that there is a reason that we visualize a spacecraft taking off from a launch rail of some kind, and that is that a two-stage to-orbit launch system will become the way that people go into space. Not cargo, just people. If we decide to utilize the atmosphere instead of fighting it, we will need a large aircraft to carry our spacecraft to a high enough altitude that atmospheric turbulence will not be a problem. Sitting on top of this aircraft will be our orbiter, with propellent and payload, which all adds up to a pretty heavy load.

This is where we can use ground-based equipment and energy to help our cause. An aircraft which could carry 1 million pounds is going to weigh a couple of million pounds. Building a set of landing gear which can support all that is going add a tremendous amount of weight to the aircraft, plus we will need an extremely thick runway to hold this weight, and the runway is going to have to be several miles long, because it will take that long for the aircraft to reach take-off velocity.

However, if we instead support the carrier wing and the spacecraft, or what I call the stack, on a wheeled sled which rides on rails, we can avoid all of those problems, and allow for a linear motor to be the primary driving force to get the stack up to take-off speed, which is likely to be about 300 miles per hour. This design would also allow for an aborted take off, as the motor can be used to slow the stack down, as well. This also avoids the problem of poor efficiency for turbofan engines at low speed and low altitude. Perhaps as many as 12 of the most efficient and powerful of these engines will be needed for the carrier wing. A climb rate of about 1,000 feet per minute will be needed, and it will still take nearly an hour to reach launch altitude.

All of this is to lift our launch pad up above most of the atmosphere, so that we can launch towards the horizon, instead of straight up. Getting into orbit is all about going fast, not going high. But rockets have to get above the thickest part of the atmosphere as quickly as possible, so they launch straight up. But that also means that we have expend huge amounts of energy to lift all that mass, whereas a wing would be able to lift the same amount of mass with a much smaller expenditure of energy.

The space shuttle weighed 4.5 million pounds at take off, with about 2.6 million pounds of that being the two Solid Rocket Boosters. All of that weight was to get the orbiter and the external tank to 150,000 feet of altitude and about one mile per second of velocity. The remaining 4 miles per second were achieved using about half the external tank's capacity, which was how much was left in it when the SRB's separated.

So the bulk of the increase in velocity came from about 800,000 pounds of fuel and oxidizer, which was burned above 150,000 feet in altitude. If we had had a carrier wing which could carry 1 million pounds to 50,000 feet, we could have launched the space shuttle without the SRB's. That was the original concept for the space shuttle, but the payloads were much smaller.

Taking off straight up demands the ultimate in engineering, reliability, and performance, because when you are going straight up, any failure will result in the vehicle falling back to Earth. Horizontal take-offs don't have that performance demand, so more safety factor can be included, and lower performance is acceptable. We don't need liquid hydrogen, we can get by with kerosene. We don't need turbopumps spinning at 30,000 rpm, 10,000 is enough.

Because the spacecraft is not traveling at Mach speed until well after separation, an abort and return to launch site is possible, especially if the carrier wing takes the orbiter uprange while climbing to altitude. Range safety requirements would be much more relaxed, and weather would not be an issue with nearly all launches.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Sun Mar 29, 2015 12:33 am
Want to make a SSTO Rail Laucher without any curve in track?

Dig a hole straight down, large enough to fit a tunnel building machine,

Aim it up at a angle,

straight shot to space,

want to do it on the cheap?

find a mineral plume and build it while recovering the plume?

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Sun Mar 29, 2015 2:31 am
Sigma wrote:
Want to make a SSTO Rail Laucher without any curve in track?

Dig a hole straight down, large enough to fit a tunnel building machine,

Aim it up at a angle,

straight shot to space,

want to do it on the cheap?

find a mineral plume and build it while recovering the plume?


The vehicle is still going to be destroyed by turbulence before it can get anywhere, even if your hole comes out at the top of Mt. Everest. There is no way known to science to travel 1 mile per second less than 100,000 feet above sea level. You have to get above the bulk of the atmosphere before you can start going fast.

My concept does not involve reaching any velocity above 400 miles per hour until the vehicle is at least 50,000 feet up. The catapult is just to make sure that the carrier wing can get going fast enough to have sufficient lift to climb away from the ground. Without the catapult, the take-off roll would be several miles long.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Mon Mar 30, 2015 12:48 am
This is why I designed zeropto

a convergent laser plasma bloom system
that would need to run for about 2 seconds.

I think that a new class of laser will be required to make it happen,

Or potentially some sort of fusion beam......

(Deuterium particle beams converge)

also I explored the idea of setting up a current in the plasma to repel it but need more creative input from people with degrees.

basically the idea is supercavitation through manipulation of a plasma bloom, however that is achieved.

side note:http://www.dailymail.co.uk/sciencetech/article-3007984/Boeing-patents-real-Star-Trek-style-force-field-protect-vehicles-buildings-explosion-shockwaves.html

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Tue Mar 31, 2015 3:57 am
http://m.phys.org/news/2014-07-optical- ... n-air.html

this makes me think it is ever more possible.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Mon May 04, 2015 12:39 pm
Your concept has a lot of potential, but requires some substantial breakthroughs to work, from what I gather. What I am championing is a process which does not need any breakthroughs, because every part of it has been done before. No, we have not built 2.5 million pound aircraft before, that is true, but we know how to build a wing, and how much power it will need to fly, so it is just a matter of building it.

We know beyond a shadow of a doubt that a winged re-entry vehicle can safely, consistently, return from orbit and land on a runway. (As long as we don't punch big holes in the leading edge of the wing.) We also know beyond a shadow of a doubt that said re-entry vehicle can ascend to orbit without being destroyed by the turbulence created by the wings.

I admit that taking off from the back of an aircraft has not been performed before, at least to my knowledge, but the principals are not unknown, and a test regime can determine the best method. Probably something involving the carrier wing diving, and the orbiter pulling up under power. Just so long as thousands of feet of altitude is not lost, as is the case with drop launches.

Once we have established a reliable, safe, economical way to put people in orbit in numbers great enough to allow real research to happen off planet, money will begin pouring into all kinds of methods of putting mass into orbit. But I am confident that the method that I purpose, or one very similar, will be the way people go to and from space for many years to come.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Wed May 20, 2015 8:26 am
I really don't understand why the two stage rocket sled assisted take off wouldn't be most efficient ( after flying to space ).

First you need to speed up the winged craft to M1-1.5 on the sled then rocket it into 180 000 ft mark at mach 4-6 and boom..release he orbiter with its boosters...you need very little effort to reach the orbit from there at that speed..it doesn't even get much heated.

Main thing is that you save lotsa weight.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Wed Jun 03, 2015 4:22 pm
The rail or bus you call is probably not more than a spaceship a space shuttle in proper moving faster than a speed of light at an appropriate cost with super turnover error free.


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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Wed Jun 03, 2015 4:23 pm
The rail or bus you call is probably not more than a spaceship a space shuttle in proper moving faster than a speed of light at an appropriate cost with super turnover error free.


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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Sat Jun 27, 2015 11:23 pm
http://www.popsci.com/secret-interactiv ... cond-laser

Plasma generation in atmosphere could actually be very efficient if the beam was tuned to the frequency of the atmosphere, and the laser emission system was very efficient.

Plasma aerospike envelope acceleration will be a thing soon enough.

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Post Re: Rail launched TSTO to Mars with just 1/10 cost of Apollo ?   Posted on: Tue Jul 07, 2015 12:26 pm
astronautdoc-1 wrote:
The rail or bus you call is probably not more than a spaceship a space shuttle in proper moving faster than a speed of light at an appropriate cost with super turnover error free.


Could you please restate that? I cannot make heads or tails of it, except for a shuttle moving faster than light. We are not talking about Star Trek, we are talking about going into orbit sometime before the next Ice Age.

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