Mountain hopping and the SpaceX machines.

Void · 2014-08-16 09:44:22

I was stimulated by conversation on another post to imagine large balloons, thought of a tower to land a rocket on to refuel, and realized we have Mountains.
I believe that Mr. Musk has indicated that the cost of lunching to orbit is mostly the machinery, and less the fuel.

It might seem logical to just build a launch pad on a mountain, but then you would have to land the boosters from orbit or very high up onto a small pad on a mountain. And also the mountain location would likely be remote from industrial infrastructure.

However I think that by first hopping from low level with a partially fueled ship to a mountain top pad to be refueled, the boosters could be downsized, perhaps saving costs.
I assume that the mountain pad would have to have a natural gas pipeline and perhaps an electrical line as well. Perhaps the fuel and oxidizer would be manufactured at the mountain base.

So various possibilities might exist. Launch with cargo, and a partial fueling. Land on the mountain base and refuel above the bulk of the atmosphere.

Launch without cargo, pick it up on the mountain base, refuel fully and then launch to orbit.

The downside is you have to pay for a mountain launch site with refueling. Also each added hop adds to the danger of a mishap damaging or destroying hardware.

But the upside is that the propulsion system could be downsized. If they get very good at landing without destroying hardware perhaps it might eventually be a way to go with cargo deliveries to orbit from the Earths surface.

One other advantage would be learning to land and launch in a thinner atmosphere on a mountain base would be a greater simulation of operating on Mars.

Last edited by Void (2014-08-16 09:48:44)

RobS · 2014-08-16 10:53:05

I suspect the cost of building infrastructure on top of a big mountain, and dealing with the extremely cold temperatures and high winds, cancels out any economic advantages. And none of them are high enough to provide a good Mars analog. If Musk wants that, he could reserve enough fuel to slow and stop a Falcon 9 first stage at 100,000 feet where the air is similar to Mars in density, then let it continue down and land at sea level.

Void · 2014-08-16 16:01:32

You could be correct. But I don't expect much serious research into the idea until the SpaceX methods have demonstrated a good certainty of reliability if ever.

Tropical mountains would be more favorable, if they also had an industrial infrastructure not too far away. There would be less seasonal variability. But even in North America,
seasonally, a system could do normal method launches in the bad seasons, and be able to lift more during favorable seasonality on the mountain pad.

There is also the leeward side of mountains/plateau's there there would be an improvement for precipitation. And there are weather forecasts also, which should be getting better over time.

My argument would continue with the notion that Papua/New Ginnie would be a good location for launches due to elevation and proximity to the equator. However other local nations might have a greater industrial infrastructure for initiating a serviced rocket with payload with a partial fueling.

Winds? Yes, that is an issue. However I have already addressed the general problem with seasons, precipitation, and so on. I would be thinking of a location at 10,000 feet if possible actually, but lower if necessary. I would also note that higher winds (If they happen) would be partially offset by lower air density.

Yes, 100,000 feet testing would be useful, but eventually if Mars is teraformed, it will have a denser atmosphere. The testing for something like that would simply occur as a consequence of operating a "Hop" launch pad.

But I think we both agree that economics would rule in the end. A yes/no answer does not apply. Maybe seems more appropriate to me. The technological conditions of the future will likely change, but SpaceX's methods suggest that hopping might get a bigger payload to orbit, or allow for a smaller rocket for the same payload.

Last edited by Void (2014-08-16 16:03:42)

Tom Kalbfus · 2014-08-16 18:26:39

Void wrote:

I was stimulated by conversation on another post to imagine large balloons, thought of a tower to land a rocket on to refuel, and realized we have Mountains.
I believe that Mr. Musk has indicated that the cost of lunching to orbit is mostly the machinery, and less the fuel.
It might seem logical to just build a launch pad on a mountain, but then you would have to land the boosters from orbit or very high up onto a small pad on a mountain. And also the mountain location would likely be remote from industrial infrastructure.
However I think that by first hopping from low level with a partially fueled ship to a mountain top pad to be refueled, the boosters could be downsized, perhaps saving costs.
I assume that the mountain pad would have to have a natural gas pipeline and perhaps an electrical line as well. Perhaps the fuel and oxidizer would be manufactured at the mountain base.
So various possibilities might exist. Launch with cargo, and a partial fueling. Land on the mountain base and refuel above the bulk of the atmosphere.
Launch without cargo, pick it up on the mountain base, refuel fully and then launch to orbit.
The downside is you have to pay for a mountain launch site with refueling. Also each added hop adds to the danger of a mishap damaging or destroying hardware.
But the upside is that the propulsion system could be downsized. If they get very good at landing without destroying hardware perhaps it might eventually be a way to go with cargo deliveries to orbit from the Earths surface.
One other advantage would be learning to land and launch in a thinner atmosphere on a mountain base would be a greater simulation of operating on Mars.

Tallest mountain we have, Mount Everest is about 8 kilometers about sea level, that leaves about 92 kilometers to get into space. I think however Nepal or Tibet wouldn't be the best location to launch a rocket from, mainly because the rockets would track over dry land for quite some distance before reaching orbit, the Chinese wouldn't like spent rocket stages raining down on them from space. I think the big island of Hawaii might be a good location to launch from, there is however an active volcano to contend with. I think there was a couple James Bond villains that launched rockets from either active or extinct volcanoes.

http://kizaz.com/2013/12/13/5-james-bon … wed-plans/
The Plan: SPECTRE under Ernst Blofeld (Donald Pleasance) uses a secret launch site in a dormant volcano to send their own spacecraft to capture US and Soviet spacecraft in the hope of starting a nuclear war that they will survive and take over in the aftermath.
The Downside: Even with 1967 technology, it’s kind of hard to launch a rocket on an island off the coast of Japan without someone knowing. The US maintained a large military presence there at the time in Okinawa, South Korea and the Philippines and rocket launches can be seen for miles. Oh, and how do you build a “secret” launch site in a dormant volcano, manned by hundreds of people without someone asking to see a building permit?
The Plan: Hugo Drax (Michael Lonsdale) builds a space station from which he will launch a biological attack the will wipe out humanity and allow him to recreate he world in his own image.
The Downside: This time the plan itself is fairly foolproof, it’s kind of hard to fight someone when the entire planets population is dead. The problem here lies in the execution. As mentioned above, it’s kind of hard to launch a space vehicle without people knowing about it. Well, you say, his launch site was in a remote jungle. Fine, NORAD had been around for about 20 years and had an established launch detection system by then. Not to mention that building a space station takes dozens of launches and at some point either the US or USSR is going to ask questions about why Drax is building a space station and why does it need a laser cannon?

Last edited by Tom Kalbfus (2014-08-16 18:34:12)

Void · 2014-08-16 19:46:48

Whats the price on that Drax thing? I wonder if I could afford Fembots too?

Yes Hawaii is a notion to consider, being American, we would not have to be at a disadvantage.

The pacific coast of the America's, and the great basin might have potential, the American Southwest, perhaps seasonally.

I am not really a rocket head, but I understand that for many rockets that have existed, flying though the troposphere is a rigor, that places constraints on how your propulsion device can fly. I think that for efficiency, it is required to follow a certain speed profile, and that that imposes a lot of drag, and so the structure of the rocket is constrained, and it uses a lot of fuel just to punch through the lower layers of atmosphere. That is what I am trying to get around.

I like the work you guys are doing on the balloon idea by the way, just didn't want to confuse it with this. Didn't want to get into a topic war.

SpaceNut · 2014-08-16 21:12:17

Void wrote:

I like the work you guys are doing on the balloon idea by the way, just didn't want to confuse it with this. Didn't want to get into a topic war.

I do remember and here are the threads with that topic....
baloon launcher - Cheap way to get to space

Is this a new idea for getting to LEO? - A possible efficient way to get to LEO?

Tom Kalbfus · 2014-08-16 23:10:12

SpaceNut wrote:

Void wrote:
I like the work you guys are doing on the balloon idea by the way, just didn't want to confuse it with this. Didn't want to get into a topic war.
I do remember and here are the threads with that topic....
baloon launcher - Cheap way to get to space
Is this a new idea for getting to LEO? - A possible efficient way to get to LEO?

The difference is, my balloon never gets off the ground, it doesn't have to be lighter than air. One interesting thing is a column of air 100 km tall resting on 1 meter square at sea level weighs 10 tons, now how much would a steel beam 100 km tall and a square meter wide weigh? Let me do the calculation.
Iron has a density of 7.874 grams per cubic centimeter. since there are 100 centimeters per meter, there are 1,000,000 cubic centimeters per cubic meter, and since 1,000,000 grams is a metric ton, there are 7.874 metric tons per cubic meter. Now 100 km is 100,000 meters, that means a column of iron 1 meters square on the base weighs 787,400 metric tons compared to just 10 tons for a column of air of similar height. Now you really can't make an iron beam that tall, as the weight of it would cause it to collapse. Mountains spread their weight over a very large base, but it would be very hard to make a 100 km high mountain, especially if its a mountain made out of rock and not air.

Last edited by Tom Kalbfus (2014-08-16 23:11:35)

Void · 2014-08-17 10:56:20

It is somewhat useful to pose a challenge as an "OR" situation, as more often than not ends up trying to stifle an idea before it has been properly evaluated.

But this is apples an oranges "AND" having both is beneficial to a diet I would state.

Mountain hopping might be attainable without a radical departure from what already appears to be an "IS'. That is if SpaceX manages to reuse hardware, and then manages to make that reliable, to a degree similar to aircraft currently in use, then mountain hopping can be evaluated for it's utility, and profitability.

An evaluation now that turns up negative, does not preclude the thought that in a future technological world it might make sense for some situations. Grown "Organically" mountain hopping could occur as a progression from the SpaceX method. Building a giant futurist balloon method is a nice idea to discuss, but lets do it on your balloon thread.

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#1 2014-08-16 09:44:22

Mountain hopping and the SpaceX machines.

#2 2014-08-16 10:53:05

Re: Mountain hopping and the SpaceX machines.

#3 2014-08-16 16:01:32

Re: Mountain hopping and the SpaceX machines.

#4 2014-08-16 18:26:39

Re: Mountain hopping and the SpaceX machines.

#5 2014-08-16 19:46:48

Re: Mountain hopping and the SpaceX machines.

#6 2014-08-16 21:12:17

Re: Mountain hopping and the SpaceX machines.

#7 2014-08-16 23:10:12

Re: Mountain hopping and the SpaceX machines.

#8 2014-08-17 10:56:20

Re: Mountain hopping and the SpaceX machines.

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