Author Topic: Space Track Launch System  (Read 37539 times)

Offline Jerry Fisher

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Space Track Launch System
« on: 12/05/2011 04:35 PM »
      What about an all electric first stage launch system with a conventional liquid propellant second stage? I have been working on such a system called the Space Track Launch System (STLS) for about eight years. The system consist of counterweights attached to ribbons which are attached to a rotating truss mounted on a tall tower. A second stage launch vehicle travels down the ribbon accelerated by gravitational, centrifugal, and Coriolis forces. At a certain point along the ribbon, the second stage launch vehicle separates from the ribbon and proceeds to low earth orbit.

     I believe this system is unique for several reasons. First, the second stage launches from the ribbon instead of from the end of the ribbon which drastically reduces the shock produced from the launch. Second, the launch velocity is the vector addition of the radial velocity down the ribbon and the tangential velocity at the launch point. Third, the counterweights are designed to absorb some of the  shock and dampen the oscillations of the ribbon after launch. Fourth, a second launch vehicle can be launched approximately 210 seconds later, doubling the payload capacity to LEO. Finally, the kinetic energy of rotation can be restored in approximately eight hours, resulting in several launches per day.

     I am relatively new in the space access business with no prior contract experience. Unless I've missed some fundamental physics, the concept should work. However, I am a physicist and not an engineer. Therefore, I humbly submit this concept and invite the forum to critically review the STLS concept at www.fisherspacesystems.com. I look forward to your review, critique, and future collaboration.

Offline Jim

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Re: Space Track Launch System
« Reply #1 on: 12/05/2011 04:51 PM »
How do you propose building the tower when it is 2 magnitudes taller than anything ever built?

Offline Andrew_W

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Re: Space Track Launch System
« Reply #2 on: 12/05/2011 05:48 PM »
How do you propose building the tower when it is 2 magnitudes taller than anything ever built?

The "when it is 2 magnitudes taller than anything ever built?" isn't relevant, like all the creative alternative ideas it comes down to: Is it possible, what's the cost, and who's going to foot the bill?

This idea is the opposite of HASTOL, which would use a rocket first stage with a tether second stage, I wonder if combining the two to get a tether to tether system would be possible.
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Offline deltaV

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Re: Space Track Launch System
« Reply #3 on: 12/05/2011 05:52 PM »
How do you propose building the tower when it is 2 magnitudes taller than anything ever built?
Maybe using a dynamic structure as commonly proposed for tall launch towers? See e.g. http://en.wikipedia.org/wiki/Non-rocket_spacelaunch#Dynamic_structures.

Offline Jim

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Re: Space Track Launch System
« Reply #4 on: 12/05/2011 06:22 PM »

The "when it is 2 magnitudes taller than anything ever built?" isn't relevant,

Nonsense, it is very relevant because it infers "Is it possible or feasible?"  Just because you dont get it has nothing to do with relevance.

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #5 on: 12/05/2011 07:23 PM »
How do you propose building the tower when it is 2 magnitudes taller than anything ever built?

That's a good question. Much, much research and development is required for this to be feasible. For a second generation tower, the tower will be approximately 150 km tall and support an estimated 3,100 metric tons. The tower will precess since it will be located anywhere from 0o to 50o north latitude. (What aerospace company wants to operate out of the north pole?) IMO, a tower under tension is the only possibility. Several authors have theorized on the possibility of tall support towers (references below).

The analysis for the support tower relies heavily on the work presented in "Feasibility of a 20 km Free-Standing Inflatable Space Tower" by R. K. Seth, B. M. Quine, and Z. H. Zhu. For the case of a second generation system, the material of choice is a carbon nanotube material with a working tensile strength of 25 GPa. The tower would be filled with hydrogen from 20 km to 150 km and helium from 0 km to 20 km. The top 10 km of tower will have to be pressurized to 4.8 x 105 N/m2. The pressure will increase as more mass is added to the tower. The initial design of the tower is in 10 km increments for the hydrogen fill and 5 km increments for the helium fill. Guy wires will be attached to retard the precession. Unfortunately, due to the elasticity of the CNT cable, the tower will sway an estimated 10 km southward with a period of 4.4 minutes. Strong stomachs are advised.

References

Fisher, J.F., 2011, Space Track Launch System - Tower, www.fisherspacesystems.com

Smitherman Jr., D.V., 2000, Space Elevators: An Advanced Earth-Space Infrastructure for the New Millennium, MASA/CP-2000-210429

Seth, R.K., Quine, B.M., and Zhu, Z.H., 2009, Feasibility of 20 Km Free-Standing Inflatable Space Tower, JBIS, Vol. 62. pp. 342-353, 2009

Bolonkin, A.A., 2003, Optimal Inflatable Space Towers with 3-100 km Height, JBIS, Vol. 56, pp. 87-97, 2003

Offline Jim

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Re: Space Track Launch System
« Reply #6 on: 12/05/2011 07:52 PM »
How do you propose building the tower when it is 2 magnitudes taller than anything ever built?

That's a good question. Much, much research and development is required for this to be feasible. For a second generation tower, the tower will be approximately 150 km tall and support an estimated 3,100 metric tons. The tower will precess since it will be located anywhere from 0o to 50o north latitude. (What aerospace company wants to operate out of the north pole?) IMO, a tower under tension is the only possibility. Several authors have theorized on the possibility of tall support towers (references below).

The analysis for the support tower relies heavily on the work presented in "Feasibility of a 20 km Free-Standing Inflatable Space Tower" by R. K. Seth, B. M. Quine, and Z. H. Zhu. For the case of a second generation system, the material of choice is a carbon nanotube material with a working tensile strength of 25 GPa. The tower would be filled with hydrogen from 20 km to 150 km and helium from 0 km to 20 km. The top 10 km of tower will have to be pressurized to 4.8 x 105 N/m2. The pressure will increase as more mass is added to the tower. The initial design of the tower is in 10 km increments for the hydrogen fill and 5 km increments for the helium fill. Guy wires will be attached to retard the precession. Unfortunately, due to the elasticity of the CNT cable, the tower will sway an estimated 10 km southward with a period of 4.4 minutes. Strong stomachs are advised.

References

Fisher, J.F., 2011, Space Track Launch System - Tower, www.fisherspacesystems.com

Smitherman Jr., D.V., 2000, Space Elevators: An Advanced Earth-Space Infrastructure for the New Millennium, MASA/CP-2000-210429

Seth, R.K., Quine, B.M., and Zhu, Z.H., 2009, Feasibility of 20 Km Free-Standing Inflatable Space Tower, JBIS, Vol. 62. pp. 342-353, 2009

Bolonkin, A.A., 2003, Optimal Inflatable Space Towers with 3-100 km Height, JBIS, Vol. 56, pp. 87-97, 2003

And how are the huge costs of this infrastructure going to make spacelaunch cheaper?

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #7 on: 12/05/2011 08:18 PM »
Quote: "And how are the huge costs of this infrastructure going to make spacelaunch cheaper? "

     A detailed cost analysis has not been done. The first task is to determine if the STLS is technically feasible. As I have said in a previous post, I am a physicist not an engineer. I have had no technical review of this concept from my peers. This forum is the concepts debut.

     Having said all that, let's review the possibilities. I see this as a government owned contractor operated facility. The GOCO approach will hopefully keep the launch cost to a minimum. It will be up to the aerospace companies to fund, operate, and maintain their second stage launch vehicles.

     Why GOCO? Because of the tax revenue generated with having approximately 6 metric tons of cargo and/or people launched into space everyday. Imagine the number of aerospace companies required to meet that launch demand not to mention all of the support facilities (machine shops, fuel depots, restaurants, hotels, maids, janitors, etc.) required to keep the aerospace engineers happy. Is there a demand for 6 metric tons of cargo and/or people per day? Not today. It is a chicken and egg problem (catch 22 or whatever you want to call it). I do see launch cost several orders of magnitude less than today. But, that is just me. As I've said, a detailed cost analysis has yet to be done.

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #8 on: 12/05/2011 08:34 PM »
How do you propose building the tower when it is 2 magnitudes taller than anything ever built?

The "when it is 2 magnitudes taller than anything ever built?" isn't relevant, like all the creative alternative ideas it comes down to: Is it possible, what's the cost, and who's going to foot the bill?

This idea is the opposite of HASTOL, which would use a rocket first stage with a tether second stage, I wonder if combining the two to get a tether to tether system would be possible.

I have looked into catching up with MXER, docking, and transferring momentum to the launch vehicle. Launching from the tower and attaching to a tether in LEO will greatly reduce the deltaV required from the launch vehicle. It turns out that the payload capability is about doubled.

Offline RanulfC

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Re: Space Track Launch System
« Reply #9 on: 12/07/2011 02:12 PM »
This idea is the opposite of HASTOL, which would use a rocket first stage with a tether second stage, I wonder if combining the two to get a tether to tether system would be possible.
Just a slight correction Andrew but the HASTOL first stage is NOT a "rocket" it's a hypersonic-aircraft, hence the "HA" in the acronym :)

It has a small set of rockets to allow it to arc slightly  out of the atmosphere to meet the tether but the main engines are air-breathing.

Quote: "And how are the huge costs of this infrastructure going to make spacelaunch cheaper? "

     A detailed cost analysis has not been done. The first task is to determine if the STLS is technically feasible. As I have said in a previous post, I am a physicist not an engineer. I have had no technical review of this concept from my peers. This forum is the concepts debut.
Ok, the point that Jim is making doesn't really need a "detailed" cost analysis a very basic one will tell you this concept is going to cost a LOT to build due to the amount of infrastructure required.

But to your "basic" question of the concepts technical feasiblity; of course it's "feasible" and could "technically" be done. I've actually seen this same idea several times before though your suggestion of counter-weights and launching from the mid-point of the teather is an interesting variant that mitagates some of the difficulties with earlier suggestions, so further work is certainly useful.

The point Jim is trying to make would probably be better stated as asking given the mega-structure of the tower and tethers, the infrastructure, and all the associated overall costs involved how does your concept help get from where we are not to where your concept becomes "cost-effective" in terms of launch capacity and price per-pound-to-orbit?

There have been many proposals for "mega-structure" or large infrastructure scale projects that have a great capacity for putting stuff into orbit for pennies-per-pound. Launch Loops, Laser/Microwave beamed propulsion, MXER, and HASTOL just to name a few and some such as SkyRamp, of EM-Launch assist can possibly be scaled DOWN to meet current needs but they all still require an intitial investment that quite large compared to simply designing a new rocket or modifying a current one.

6 metric tonnes (@13,227lbs) per day to orbit far exceeds current demand and one thing that many advocates of space launch concepts don't seem to understand is that you MUST be able to address CURRENT needs in order to build UP future capacity. I've said it before and I will continue to point out that Space Colonization nor large scale "use" of space are NOT currently a paradigm for any government space program, and they make up a major portion of the payload market. The OTHER percentage of the market is a commercial space utilization business who have evolved to launch large payloads into specific orbits rarely and with little or no need or incentive to subsidies over-capcity or expanded capacity for space launch.

Given the above circumstances there is clearly no government forseen need or interest in a huge investment for such a system unless there can be a case made for increased national interest or dire need in the forseable future, and even less within private industry.

So having said all that, am I saying your concept has no justification and therefore you need to move on and forget about it? Oh HELL no! :)

You've done some good work so far and I say "keep it up!" Because while there is no "need" for it now that does not say that circumstances might not change in the future and even if YOUR specific concept doesn't ever get built you COULD inspire someone who's system does :)

So keep up the work and I'll try and get back after some more review with some semi-technical questions I've got on the system.

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #10 on: 12/09/2011 07:45 PM »
But to your "basic" question of the concepts technical feasiblity; of course it's "feasible" and could "technically" be done. I've actually seen this same idea several times before though your suggestion of counter-weights and launching from the mid-point of the teather is an interesting variant that mitagates some of the difficulties with earlier suggestions, so further work is certainly useful.

  The idea that the second stage launch vehicle is launched from the middle of the ribbon, the idea that the overcarriage remains on the ribbon providing a retarding force, and the idea that the counterweights absorb the shock and dampen the oscillations make this concept possible.

   It is physically impossible to launch an 80 ton spacecraft with a 1.5 ton payload from earth into low earth orbit from the end of a tether more than once. First, you would only be allowed to launch cargo and not people. People would not be able to withstand the continuous 6g acceleration during the ramp up of rotational kinetic energy. Acceleration down the ribbon as in my concept is exponential going from 3g to 6g in the last 15 to 20 seconds. It is more like an impulse in acceleration as opposed to continuous.

   Second, releasing an 80 ton spacecraft from the end of the ribbon produces a compressive shock wave which travels up the ribbon at the speed of sound for the material gather energy as it goes. This energy is above or at the failure energy for the material. If it doesn't destroy the ribbon, you certainly don't want to use it again.

   Finally, when that shock wave strikes the tower, all heck is going to break loose. This is like stretching a rubber band and letting it hit your hand but, much worse. With a counterbalance on the other side, the tower will most likely collapse.

   Therefore, launching from the end of a ribbon or tether from earth to low earth orbit using spacecraft with significant payload capability is out. The tower and the ribbon will have to be replaced after every launch. Kind of like throwing the first stage away after every launch, something I'm trying to get away from.

   In my concept, launch is possible again after eight hours. But is it technically feasible? That is what I hope to answer with intense technical debates on this forum and through my web site at www.fisherspacesystems.com.
« Last Edit: 12/24/2011 02:04 PM by Jerry Fisher »

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #11 on: 12/11/2011 08:59 PM »
6 metric tonnes (@13,227lbs) per day to orbit far exceeds current demand and one thing that many advocates of space launch concepts don't seem to understand is that you MUST be able to address CURRENT needs in order to build UP future capacity. I've said it before and I will continue to point out that Space Colonization nor large scale "use" of space are NOT currently a paradigm for any government space program, and they make up a major portion of the payload market. The OTHER percentage of the market is a commercial space utilization business who have evolved to launch large payloads into specific orbits rarely and with little or no need or incentive to subsidies over-capcity or expanded capacity for space launch.

   Webster's dictionary defines paradigm as a philosophical or theoretical framework of any kind. Your comment appears to be philosophical in nature. So let's talk philosophically.

   Many aerospace scientist, engineers, and administrators strongly subscribe to the current philosophy. We must be able to address current needs in order to build up future capacity. Since the government is our majority customer and they demand zero risk and have large sums of money, lets do it the tried and true way with expendable throwaway booster costing $100-$200 million a launch. I understand this paradigm.

   If the government was putting a $1 billion dollar national defense satellite into a geostationary orbit, I'd want zero risk and wouldn't mind if the launch cost $100-$200 million. I think it is great that smaller commercial companies (i.e. SpaceX and Orbital Sciences) are building future capabilities based on current needs. These companies are improving on conventional technology and driving cost down through better management of resources. But, launches still cost between $100-$200 million.

   Here is where we differ in philosophy. My definition of future needs is space based solar power satellites in geostationary orbit, mining helium 3 on the moon, prospecting and mining strategic materials on near earth asteroids and in the asteroid belt, and yes, large scale colonization to support the activities. The future needs as defined above may take a little longer to accomplish but are, in my opinion, none the less important. The planet is running out of strategic materials and energy resources and I foresee a thriving export business from space based assets to earth. And to do that, we need reusable first and second stage launch vehicles with launch cost several orders of magnitude lower than presently available. People and cargo will need to go and come from LEO on a daily basis. What I and other "space advocates" are trying to establish is a new philosophical framework for space access. The mega-structure concepts such as MXER, Space Elevator, Electromagnetic Launch, and others are laying the groundwork for a new philosophical framework for space access and I, for one, am betting on the new paradigm.
« Last Edit: 12/24/2011 02:00 PM by Jerry Fisher »

Offline Rocket Science

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Re: Space Track Launch System
« Reply #12 on: 12/11/2011 09:48 PM »
"The laws of physics are unforgiving"
~Rob, Physics instructor, aviator, vintage auto racer

Offline mboeller

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Re: Space Track Launch System
« Reply #13 on: 12/12/2011 06:01 AM »

Offline Jim

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Re: Space Track Launch System
« Reply #14 on: 12/12/2011 02:02 PM »
My definition of future needs is space based solar power satellites in geostationary orbit, mining helium 3 on the moon, prospecting and mining strategic materials on near earth asteroids and in the asteroid belt, and yes, large scale colonization to support the activities.

None of which may be technically viable or even commercially viable.

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #15 on: 12/13/2011 08:11 PM »
My definition of future needs is space based solar power satellites in geostationary orbit, mining helium 3 on the moon, prospecting and mining strategic materials on near earth asteroids and in the asteroid belt, and yes, large scale colonization to support the activities.

None of which may be technically viable or even commercially viable.

On the contrary, I believe, as do many others, that they are technically and commercially viable. Lets take space based solar power satellites for example. Goggle space based solar power. Let me point out a few of the first page topics:

   - Wikipedia, ok it seems like a Wikipedia definition is always a first topic.

   - Dec 13, 2008 - "Hosted by the Space Frontier Foundation to assist the National Security Space Office study on Space-Based Solar Power development." The National Space Society published a report to the Director, National Security Space Office on the national security issues related to SBSP. The report is online at www.nss.org/settlement/ssp/library/nsso.htm.

   - Nov 14, 2011 - "A consortium of the world's leading space scientists believe that it is possible for the world to begin to meet its energy demands..." The International Academy of Astronautics has spent several years studying SBSP. Its report, completed in August, 2011, is online at iaaweb.org/iaa/Studies/sg311_finalreport_solarpower.pdf.

   - May 11, 2011 - "Space Energy seeks to improve the lives of millions of people, provide viable alternatives to polluting energy sources and help abate some of ...."  Space Energy is a space based solar power company. Their main office is in Switzerland with branch offices in California, Florida, United Arab Emirates, and China. They have a bevy of investor and shareholders. It could be just me but, I think they are pretty serious. Maybe, I should talk to them about investing in inexpensive and routine access to space a la the Space Track Launch System. I personally don't think SBSP is the answer but, I'm not going to turn down a paying customer.

   Lets look at mining helium 3 on the moon. Google mining helium 3 on the moon. Let me point out a few of the first page topics:

   - Wikipedia, ditto

   - Dec 7, 2004 - "An Apollo astronaut argues that with its vast stores of nonpolluting nuclear fuel, our lunar neighbor holds the key to Earth's future." This is a Popular Mechanics article. Not generally considered a scientific journal but yet usually very informative on down to earth issues.

   -  "Mining the Moon. Lab experiments suggest that future fusion reactors could use helium-3 gathered from the moon. Thursday, August 23, 2007; By Mark Williams ..." This is a Technology Review article at www.technologyreview.com/Energy/19296/.

   - Dec 15, 2006 "The Council is chaired by Apollo 17 astronaut Harrison Hagan "Jack" Schmitt, a leading proponent of mining the moon for helium 3. Schmitt ..." The quote is from Wired at www.wired.com/science/space/news/2006/12/72276?currentPage...

   - Mar 22, 2006 "Russia To Mine Helium-3 on the Moon by 2020. According to an official statement released in January, the mining of helium-3 on the Moon will ..." The quote is from www.ufodigest.com/helium3.html. If Russia is going to do it, we better do it to.

   I don't want to go through it here but you might check out inertial electrostatic confinement fusion research at the University of Wisconsin and MIT. Their primary choice of fusion material is helium-3 which does not exist in a free state on earth. Also, I believe the University of Wisconsin is working on extraction techniques. The concentration of helium-3 on the moon is so small, you need hundreds of processors massing several metric tons each. I think they will be happy with economical and routine access to space a la Space Track Launch System.

   Is it commercially viable? It is estimated that helium-3 has a market value of over $15 trillion per metric ton (1997, J.S.Lewis, Mining the Sky). This is not only a noble cause but more importantly a high profit margin even for commercial launch systems.

   The near earth asteroid Amun is about 2 km in diameter and has a mass of approximately 30 billion tons (1997, J.S. Lewis, Mining the Sky). Assuming a typical iron composition, the asteroid has an iron and nickle content worth $8 trillion, a cobalt content worth $6 trillion, a platinum group content worth $6 trillion, and together with its nonmetallic components, the total market value of Amun is well over $20 trillion. I like John Lewis' idea of turning the asteroid into Swiss cheese by mining out the strategic metals, getting rich, and saving the planet at the same time. Is this a great country or what?

   There is a great many opportunities in space. Getting there is the problem and that is why I'm working on the Space Track Launch System.
« Last Edit: 01/10/2012 12:35 AM by Jerry Fisher »

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #16 on: 12/13/2011 08:20 PM »
Have a look at this...

http://www.infoblog.us/2010/12/nasa-adds-turbojets-and-rockets-to-its.html

Thanks for the link. It's nice to keep up with the competition. Competition is good.

Jerry

Offline Jim

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Re: Space Track Launch System
« Reply #17 on: 12/13/2011 08:28 PM »

   I could go on about space colonization but I'm getting writers cramp. Google it yourself and you will find that you are in the minority concerning your comment on technical and commercial viability. There is a great many opportunities in space. Getting there is the problem and that is why I'm working on the Space Track Launch System.



No, not true. 
A.  You can always get more hits on pros for subject vs cons
b.  Science fantasy even gets more hits that all of yours combined.

1.  Terrestrial solar power will always be cheaper and more viable than SBSP.  There will never be an economic justification for SBSP.  There is enough barren land on the earth.
This is the majority opinion.

2.  helium-3 is still useless on earth.  They are no closer to fusion with it now as they were 30 years ago

3.  mining asteroids for terrestrial use is not viable either.  Getting the material to the surface is where is fails.  Mining asteroids is for ISRU and building hardware not intended to go back to the earth's surface.





« Last Edit: 12/13/2011 08:30 PM by Jim »

Offline Jerry Fisher

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Re: Space Track Launch System
« Reply #18 on: 12/13/2011 08:42 PM »
how about this:

http://electrictakeoff.com/
Again, thanks for the link. I've done a few back of the envelope calculations based on the information in the article and it seems that at the point where the payload is removed from the hardness and attached to the ribbon, the resulting acceleration (i.e. the square root of the sums of the square of gravitational acc. and centrifugal acc.) retards the motion up the ribbon. In other words, the payload will begin to come back down the ribbon. I'll need more info to be sure. Its nice to keep up with the competition.

Jerry

Offline johncarpinelli

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Re: Space Track Launch System
« Reply #19 on: 12/14/2011 05:25 AM »
Hi Jerry,

I like the Space Track Launch System proposal. I hope the concept gains traction and the technical feasibility can be proven. I think a flying prototype is a good way to publicize the idea and prove some of the principles.

I am an engineer working on the electric takeoff project. The payload is an aircraft with wings. The payload should generate lift as it releases from the harness and transitions to the climb on the ribbon. At the transition point, it will be travelling as fast as the tow aircraft (e.g. Mach 0.4). Our initial goal is point-to-point transport so the glide ratio for the payload should be high.

As the payload climbs to higher altitudes the aerodynamic lift from the wings will be reduced due to lower atmospheric density, but the angle of climb on the ribbon should be lower to compensate. The ribbon flies as a wing at the highest possible altitude supported by its lift.

Both the velocity of the payload and the centripetal force will increase with greater radius. The system parameters are flexible and should be adjusted to allow a continuous climb up the ribbon using a combination of forces. To calculate the net forces on the payload, you need to consider the following:
-centripetal force
-gravity
-drag
-aerodynamic lift
-the reactive force from the ribbon

It's not an easy system to model. Let's continue the discussion and hopefully collaborate on some of the technical work.

Coincidentally, I published a short piece on inflatable space towers a few days ago on our site (http://electrictakeoff.com/blog). Would it be possible to build a space tower using a pyramid of inflatable spheres strapped together? Would that reduce the strength requirements for the construction material?

John

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