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dmccarroll
2006-Mar-28, 05:36 AM
I am currently working on a research paper on future space transportation infrastructures. I was wondering if any of you might have any ideas on this subject and/or recommend any resources I may not have thought of. What I am thinking of is looking at current air transport systems and thinking through way of evolving them into space transportation systems, organizations and equipment to provide transport not only to space tourists, but for commercial operations as well.

Any constuctive thoughts are welcomed.

Launch window
2006-Mar-28, 12:02 PM
Airtransport into spacetransport ? Sorry, it just doesn't seem to work that way, they tried making those Buck-Rodger space ships like the X-15 but they have limited ability.

http://www.bautforum.com/showthread.php?t=35965
larger exhaust velocity ?

publiusr
2006-Mar-30, 07:54 PM
One of the books you might want to read is SPACEFLIGHT IN THE ERA OF AEROSPACEPLANES and some of the fine books by www.cgpublishing.com

Also check out www.up-ship.com
In SPACEFLIGHT IN The ERA...the final chapters talk about the best ways to really get infrastructure in space.

We are used to mid-sized comsat launchers and that has poisoned our perception. The boosk suggests that HLLVs be used for assembly of large structures with smaller (future) RLVs servicing them. all other expendables would be phased out at that time. RLV payloads would be small--and the HLLVs large and simple.

One of the reasons behind ALS/NLS was to force payload builders to not depend so heavily on the Launchers own systems--as many payloads made for nightmares in the sleep of the Titan enginners who kept having to keep up with the payload guru's latest demands.

Build the LV big, and tell the payload folks "There, you ought to have room. I'm not going to tie much into my system--and your craft is just going to have to take care of itself beyond a few simple systems."

Needless to say, this was shot down. It made too much sense. At least we got a little better with the EELVs, but they haven't really replaced Titan IV yet. Delta IV 'heavy' undershot by 10,000 miles. We will have to wait and see if it lives up to its hype. It will allow for larger probes, which aren't exactly getting smaller:

--From the web (Space.com)

March 29

Mars Science Laboratory: Huge Aeroshell Needed

When NASA’s Mars Science Laboratory (MSL) departs in 2009 for the red planet, it will be cocooned in a giant aeroshell. This blunt-nosed cone protects the big rover from the intense heat and friction generated as the aeroshell system descends through the Martian
atmosphere.

The MSL heatshield will be the largest ever built. At some 15 feet (4.5 meters) the hardware even dwarfs the Apollo capsule heatshields.

For comparison, the heatshields of the Mars Exploration Rovers – Spirit and Opportunity – measured 8.5 feet (2.6 meters) while the Apollo capsule heatshield measured 12.8 feet (3.9 meters).


Lockheed Martin has been awarded a preliminary design and concept study start-up contract for the MSL aeroshell system by NASA’s Jet Propulsion Laboratory. The aerospace company will draw in part upon its aeroshell/thermal protection know-how used for the Viking missions in the 1970s, as well as the Mars Pathfinder, Spirit and Opportunity missions, and the return capsules utilized for the Genesis and Stardust projects.

Lockheed Martin is also making use of expertise honed for its bid to build NASA’s Crew Exploration Vehicle – a capsule design that is 16.5 feet (five meters) in diameter.

Aireal
2006-Mar-31, 08:45 AM
Space Infrastructure, The next driving force in ship and colony design?

NASA talks about going back to the moon and using it as a springboard to Mars, but I have heard no serious talk of how a moon base will be built or supplied. In the near future there will be a need for a cheap transport ship from the International Space Station to the Moon, There may also be the need for a second space station in orbit around the moon. However, I have not heard of NASA nor anyone else working on this need.

We don't need the U.S.S. Enterprise for this mission, not even a fancy shuttle, just cheap transport. Well, cheap by spaceship standards I mean. To ease loading and unloading of cargo, the ship should have a cargo area with bay doors like the shuttle. A robotic arm could unload cargo containers straight from shuttles bay to the transports cargo bay. A robotic arm at the Moonbase Space Station would unload it, load it if needed, before making the return trip.

As this ship design needs to be cheap, but work for a number of years, an ion drive would be the best bet. Another more powerful drive could be added for getting up to speed, breaking, and so on. With a cargo ship, time is not as important, so you might get by with just an ion drive as the main drive. To cut costs even more, these ships could be automated to perform this task, with remote manual overrides of course. People would be needed to supervise loading and unloading, unless this could be automated somehow also. But people would still be needed close by, to take remote control if needed. We can cut the costs of these transports even more by using solar panels as the main power supply. Over time a whole fleet of these little ships could be making cargo runs.

Other issues need to be addressed if these ship are to be the main transport vessel. What if we need to move items that will not fit in the cargo bay? This is best addressed by making the ship modular in design from the start. If the command and engine modules could be separated from the standard cargo module, and then be attached to any other type of module, then you would have versatility. Versatility like this will be what we need to expand into space, building stations and colonies as we go. Modules for such space construction could be put in place of a cargo module for transporting to the site. After delivery, the command and engine modules are reattached, and a much shorter ship, makes the return trip.

This concept of modular versatility can be extended to ease the construction of space stations and colonies as well. As these transport ships age, ion drives, solar panels, and the like will degrade. These ship could be refitted, or used as building material for other space structures. Waste not, want not, I was always told. Once a ship has paid for itself plus a little profit, it may make good business sense to replace them with new ships, and recycle the hulls for other projects. This would give a head start on construction, and reduce the new projects overhead. Let's examine how this would work.

The moonbase space station I mentioned, would not be much of a station, even smaller than the I.S.S. as its main job is just to transfer cargo. Picture one of the cargo ships, with a large flat staging area and a robotic arm instead of the cargo bay module, the ion drive being used to keep it in orbit. The robotic arm would remove a cargo container from a ship and place it in a landing pod on the staging area. The pod is released from the staging area by electro-magnetic locks, and the robotic arm would move it off to the side of the platform to begin decent to the moon. On the surface, crews would unload the cargo, refill the pod, and send it back up. Once there the robotic arm would place it back on the staging area, and lock it back down till needed again. The first real test for our modular approach will not be here, but when we head to Mars, or elsewhere.

Mars will need a far larger space station than the I.S.S. in Earth orbit. Large enough that we could test some space colony concepts here. If it were up to me, we would head to the asteroid belt before Mars, as I believe we will need material from the asteroid belt to help build other colonies. NASA has yet to ask my opinion on this matter, so until then, we will most likely go where they lead. With water being one of the main resources we will need in space, a spot near an icy moon may also be a good location for a space colony. As I have not gave a great deal of thought as to the mission need of a space station/colony in orbit over Mars, so forgive me if I pass on this subject for now and move on to the first space colonies. One last thought before I move on that I just had. The space colony in orbit around Mars has a magnetic field as one of its radiation defences. Will this change the amount of radiation hitting the ground in its shadow? If so, would it be worthwhile to use a network of satellites to provide some protection for the colony on the planet? Please read my post on ion drives and radiation shielding. Now let's move on.

Any early colony in space will start near some resource. Later some may be built for other reasons, and have vastly different concepts, but not at first. Because they are there to exploit some resource, they need to be productive almost from the start. So any design for a colony must allow for the expansion that will come. This limits us in the type of colony we can build to a degree. The first concept that comes to mind would resemble a spoked wheel with a hub. But as it grows, that may change. By locating the positive and negative poles of our Rad. Shield at the ends of the hub, the central spokes and ring are in the zone of max. protection. More spokes and more distant rings would be added. The hub would be extended to allow for more spoke and ring levels. The final form may be sphere of large rings, connected by spokes and tubes. This end design would keep all areas within the shape of the magnetic field. In short, it needs to be built of modular sections that can be moved, changed, or modified as the colony grows.

Lucky for us, we started with a modular approach to space travel and construction. Before the first crew arrives, a number of our supply ships will have been sent ahead and waiting. In addition to a full cargo hold, each one will have a extra module for the colony construction. The crew would arrive in a ship with a construction module. It would have extended crew quarters, robotic arm, and airlocks. The crew would live and work from this ship till the base of the hub of the is built. Then other crew can arrive to start mining operations, do internal work on the colony, and so on. With every supply ship comes one more module to add to the growing structure. Like any settlement, it will draw people for many reasons. The growth may be rapid. Companies will want access to the colony for the profit resources and people provide.

At this point the space race will begin in full force. Those at the front of this movement stand the most to gain, or lose. New technologies will come at an increasing rate. But we will need a fleet of supply ships to get us this far. They won't be any any art praising their elegant shape, no movies about it and the crews 5 year mission to haul water to thirsty people. The supply ships have nothing going for them except the will be cheap, and they will get the job done. They will be the backbone of space exploration.

Hope this helps dmccarrol, its just a thought I had a while back.

NEOWatcher
2006-Mar-31, 01:14 PM
NASA talks about going back to the moon and using it as a springboard to Mars, but I have heard no serious talk of how a moon base will be built or supplied. SNIP
Maybe they are making a full determination of what CAN be done before saying anything that might sound like a commitment. :think:
I can just see it now... NASA says let's see if x, y, and z exist to build a moon base, and PopSci publishes the 5 year plan and full design specifications of their moon colony. NASA lands a research ship, and everyone says, why is there no lunar inn... bad NASA, bad.


As this ship design needs to be cheap, but work for a number of years... snip

All of your ideas sound good and feasible. The problem is that it is going to take a long time to get there. Taking it one step at a time sounds good to me, because you don't want step 4 to be messed up because of something you found in step 3. (for instance, get to the moon to make a better determination of where and how to mine for resources).
I do see some flexibility in the current NASA plans for the near future, let's hope that's the goal.
Now that the goal is long term, I think we are almost back to square one for interplanetary travel. The only time man has been to the moon has been "lets just get there" and do it a few times so we can find out about the moon. Now the goal is different, and I'm sure that means new technologies and new thinking.
I, personally, will be patient for a short while to see how things will unfold.

Wow, 5 posts and nobody's pushing the SE.

Ara Pacis
2006-Apr-02, 12:55 AM
I am currently working on a research paper on future space transportation infrastructures. I was wondering if any of you might have any ideas on this subject and/or recommend any resources I may not have thought of. What I am thinking of is looking at current air transport systems and thinking through way of evolving them into space transportation systems, organizations and equipment to provide transport not only to space tourists, but for commercial operations as well.

Any constuctive thoughts are welcomed.

Are you thinking of something like the defunct X33 spaceplane or the purported "Black Star" project?

dmccarroll
2006-Apr-03, 04:03 AM
I am aware of the Blackstar Project as well as other ideas. However, I am keeping an open mind as I do my research to see who may come up with the most practical ideas. My paper will probably include many different types of transport vehicles along with other infrastructures and the organizational aspects of a space transport corporation. I also intend to talk about the regulatory side as we all know the governments will have to get involved. Last, but certainly not least, I want to explore the safety aspects and what we will need to do to implement safety measures to insure survival of the people involved as well as the industry. As mentioned already, If I use any of the ideas, you will get credit in my footnotes and bibliography.

By the way, I am working on a Master of Aeronautical Sciences degree at Embry-Riddle Aeronautical University with specialization in Space Studies. That being said, I may be seeking research material quite often in the next couple of years.

Thanks for all the help so far. There are some good thoughts and I is a big help in my deciding which way to go with my paper.

Nicolas
2006-Apr-03, 10:00 AM
I am aware of the Blackstar Project

You mean, about the rumors concerning the Black Star Project :) ;)

Larry Jacks
2006-Apr-03, 08:13 PM
Just my personal opinion, here's how I'd like to see a space infrastructure evolve over the next 20 years or so.

1. We need an economical way to launch from the Earth's surface to low Earth orbit (LEO). Personally, I'd like to see separate vehicles for launching humans into orbit and for launching payloads. Heavy Lift Launch Vehicles (HLLVs) have some uses but I don't know if we'd launch enough of them to be worth the billions in R&D costs. For missions going to the moon or beyond, I wouldn't want to launch to the ISS because it's in a relatively high inclination orbit (51 degrees) that causes a significant performance penalty compared to a lower inclination orbit.

2. For trips between LEO and lunar orbit, I'd like to see a reusable transport vehicle designed to carry humans and materials. This vehicle would have substancial payload capacity, such as the ability to deliver 10-20 metric tons into lunar orbit. For the return trip, aerocapture and/or aerobraking using the Earth's atmosphere would greatly reduce the energy requirements to go into LEO.

3. For trips between lunar orbit and the lunar surface, I'd like to see a fully reusable vehicle. In the early years, this vehicle would probably need to use hypergolic propellants. Later, if harvestable lunar water resources are found, I'd like to transition to propellants that can be made from lunar resources (e.g. LH/LOX or LOX/methane). As a design goal, this lander should be able to carry a substancial payload from lunar orbit to the surface, say 10-20 metric tons.

If, and this is a big IF, harvestable lunar water is found, I'd like for it to be launched from the lunar surface for use in Earth orbit. That water could be converted into propellant and other oxygen for things like refueling the LEO-Lunar Orbiter vehicle. It could also be used to refuel space tugs to loft payloads from LEO to GEO or even interplanentary missions. The tugs would rendezvous and dock with payloads delivered into LEO and boost them to their desired orbits. This could greatly lower the costs of launching deep space payloads. Consider the case of a two metric ton payload launched from Balkinor (Tyuratam) to GEO. Today, it takes a vehicle like a Proton booster to loft such a payload. Several years ago, I read that the base Proton booster is capable of launching 20 metric tons to LEO. To reach GEO, it needed an 18 metric ton upper stage due to the magnitude of the plane change. Imagine how much less expensive it could be to simply put the payload into LEO and have a reusable tug boost it to GTO or even GEO.

I can dream, can't I?

Nicolas
2006-Apr-03, 08:33 PM
You have a clear dream, and a quite realistic one. I don't think we'll have that in 20 years, but I mean that your dream is something that we *could* have.


On your final point: launching from the equator does help for GEO orbits.

The problem with LEO-GEO tugs is that they need to go from LEO to GEO (to do their job), refuel, go back to GEO, lift something to GEO...the tug uses up energy to go back from GEO to LEO. So there must be a really good fuel source (energy source) in space to justify that.

Larry Jacks
2006-Apr-03, 09:18 PM
Launching from the equator has a tremendous benefit for satellites bound for GEO. It takes a lot of energy to perform an orbital plane change.

The tug that I envision would be refueled in LEO, pick up the payload, and boost it to GEO. After separation, the tug would need enough propellant to drop the perigee low enough for aerobraking to drop the apogee (just like the aerobraking being performed on MRO). Aerobraking also allows you to change the inclination to the same as the refueling station.

For interplanetary missions, the tug would need enough propellant to boost the vehicle onto the proper trajectory then to perform a burn powerful enough to return to the Earth.

Having a reusable tug allows you to avoid throwing away the propulsion system, guidance system, TT&C system and other components with every launch. Back in the 1980s and into the 1990s, NASA and others sometimes used an Inertial Upper Stage to boost payloads from LEO to GEO (and beyond on at least one occassion). From what I recall, the IUS cost over $100 million and weighed something like 45,000-50,000 pounds at launch. That's a lot to launch and a lot to throw away with every mission.

publiusr
2006-Apr-06, 08:32 PM
HLLVs are a must when it comes to architecture--it reduces asswembly and multiple LV costs over time. EELV assembly and RLV costs are what are unsustainable.

Ara Pacis
2006-Apr-07, 06:10 AM
Can we use the aluminum and oxygen in the lunar regolith to make rocket fuel? I think the artemis project claims that.

Larry Jacks
2006-Apr-07, 06:51 PM
An HLLV will cost billions to develop. To get an idea of how much, I read just this morning that NASA's estimates for modifying the current Shuttle SRB for use on the CEV has increased from $1 billion to $3 billion. NASA doesn't know how to contain costs very well.

CLV cost escalation (http://www.nasawatch.com/archives/2006/04/clv_cost_escala.html)

The only way it will be more economical is if the launch rate is high enough to amortize the R&D costs. Suppose it cost $10 billion to develop a HLLV (not an unreasonable estimate given NASA's track record). How many launches per year do you realistically expect to have for the system and for how many years. If you end up only using it twice a year for 20 years, you only end up with 40 total launches to amortize the R&D costs, coming to $250 million per launch just to cover the R&D. That doesn't even begin to cover the costs of building and launching the HLLV.

Personally, if it turns out that an HLLV is really needed, I'd like to investigate the costs of reviving the Energia or Energia M. The R&D costs would be minimal, the major components like the engines are still in production, and it offers tremendous payload flexibility.

Energia (http://www.astronautix.com/lvs/energia.htm)
Energia M (http://www.astronautix.com/lvs/energiam.htm)

NEOWatcher
2006-Apr-10, 12:36 PM
An HLLV will cost billions to develop. To get an idea of how much, I read just this morning that NASA's estimates for modifying the current Shuttle SRB for use on the CEV has increased from $1 billion to $3 billion. NASA doesn't know how to contain costs very well.
snip

I think a lot has to do with the fact they can't estimate well, and that may be by design.

It's common (at least in my world) that to define a project estimate, you start with ideal conditions. Then you define the risks, the possibilities of them occuring, and the cost involved in solving the risks. Then you add in the costs of the most likely risks. (Around here, there are certain roadblocks that shouldn't happen but always do). Those that you don't add in, you mention as a possibility to document any future issues.

The general public doesn't want any risk at all, so NASA must present the ideal conditions as the estimate, hope for the best, and explain later.

(At least this is how I relate to it.)

Larry Jacks
2006-Apr-10, 08:48 PM
I think a lot has to do with the fact they can't estimate well, and that may be by design.

It's a widespread practice in government contracting called "low balling." Some organization or company will propose a price for doing something (just about anything from Boston's 'Big Dig' to DoD work to NASA projects) and come up with a really low estimate. Once Congress funds the project and work begins, the price keeps escalating. Most of the time, the project keeps getting funded because "we've already spent so much money on it, we can't stop now."

Some of the time, this is due to poor management. However, in my experience, most of the time this is a deliberate manipulation. Who cares if the project costs too much, we can always hit up the taxpayers for more money. Since politicians get their power from spending money in their own districts and since project managers learned to let subcontracts in just about every Congressional district for each major project, the game goes on. Outright project cancellations due to financial mismanagement are pretty rare.

publiusr
2006-Apr-12, 09:47 PM
An HLLV will cost billions to develop. To get an idea of how much, I read just this morning that NASA's estimates for modifying the current Shuttle SRB for use on the CEV has increased from $1 billion to $3 billion. NASA doesn't know how to contain costs very well.

CLV cost escalation (http://www.nasawatch.com/archives/2006/04/clv_cost_escala.html)

The only way it will be more economical is if the launch rate is high enough to amortize the R&D costs. Suppose it cost $10 billion to develop a HLLV (not an unreasonable estimate given NASA's track record). How many launches per year do you realistically expect to have for the system and for how many years. If you end up only using it twice a year for 20 years, you only end up with 40 total launches to amortize the R&D costs, coming to $250 million per launch just to cover the R&D. That doesn't even begin to cover the costs of building and launching the HLLV.

Personally, if it turns out that an HLLV is really needed, I'd like to investigate the costs of reviving the Energia or Energia M. The R&D costs would be minimal, the major components like the engines are still in production, and it offers tremendous payload flexibility.

Energia (http://www.astronautix.com/lvs/energia.htm)
Energia M (http://www.astronautix.com/lvs/energiam.htm)

That I would like.

Imagine the cost of disposing 15-18 RS-68s per 100 tons as opposed to 5. EELVs will cost more than HLLV and will require ISS assembly and nightmare pad delays. HLLV will get STS costs and run on those. Without the orbiter costs will drop. Doing the stick first causes problems though.