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Secret plan to privatize shuttle; now, to a next-generation shuttle.
Note: redacted newsgroups to only sci.space.policy and sci.space.history
Kuznetz later on in the interview says instead of costing us $2 billion a year, their plan could be making a *profit* of $1.4 billion a year. Sounds like a fantasy to me. One summary comment before I get into details. It seems highly unlikely that the shuttle (even a fully automated Shuttle-C configuration) would ever likely compete with the current generation of EELVs and esp. the upcoming generation of "heavy" version of these, include Falcon 9 Heavy when it comes to putting payload into LEO, regardless if that payload is cargo or fuel. You can talk $25,000 / kg or $10,000 / kg but the reality is the heavy versions of ELVs are shooting for $1000 / kg to LEO which is an entire order of magnitude lower. To move from LEO to GEO is even less costly. There is no way shuttle is going to compete with that. The one unique capacity of shuttle, to return objects from space, no one seems interested in paying for. I can only think this must be coming from those alternative income streams he mentioned that he says could be more profitable than satellite launching. On another forum someone raised the possibility of satellite servicing. I like that idea but mostly in regards to refueling satellites, especially in GEO. Most communication satellites have to be replaced not because they stop operating or become obsolete, but simply because they run out of fuel for station-keeping. Agreed. But recognize that none of the current generation GEO satellites were designed for that. You can't just simply rendezvous, dock and insert a hose. The Air Force put out a request for proposals for spacecraft that could refuel satellites in GEO. And NASA has plans for doing testing of the satellite refueling process. If you consider that the larger GEO communication satellites may cost hundreds of millions of dollars and the cost to launch them may cost in the range of $100 to $200 million, it becomes clear there would be a substantial market for refueling satellites in GEO. If they could benefit from it. They can't. You'd have to attach a separate 'maneuver unit' with that capability. That the Air Force put out an RFP may mean they are considering it for their birds or more likely a future generation of birds, but its a huge stretch to go from what *might* transpire in the military sector to that which currently exists in the commercial sector. Satellite Refueling in Orbit, Coming Soon? By Steve Rousseau October 17, 2011 5:00 PM http://www.popularmechanics.com/tech...it-coming-soon Space Infrastructure Servicing. http://en.wikipedia.org/wiki/Space_I...ture_Servicing According to the "Satellite Refueling in Orbit, Coming Soon?" article a satellite may last 10 to 15 years. According to the "Space Infrastructure Servicing" wikipedia page, 200 kg of fuel may provide an additional 2 to 4 years of life. So it might take 100 kg per year for fuel, and over 10 years would require 1,000 kg. The cost to get anything to GEO, including this fuel, is in the range of $20,000 to $25,000 per kg. So for 1,000 kg of fuel to get to GEO for satellite refueling it would cost perhaps $25 million. But this would double the life of the satellite since it would again have a full fuel load for 10 years. So for $25 million you saved the satellite companies from paying, say, $300 - $500 million, to purchase and launch a new satellite. It would be cheaper (by far) to launch an ELV with a fuel container. (See above). So even if you charged 4 times the usual price to get to GEO for this fuel, the satellite companies could still consider this a bargain. You would need a small reusable servicing spacecraft to launch from the shuttle payload bay to transport the fuel to GEO. If you use LH2/ LOX propellant for this spacecraft like the Centaur upper stages, then it takes about the same amount of propellant to get to GEO from LEO, as the mass of the spacecraft + payload, the payload being the refueling fuel in this case. The dry mass of the spacecraft is only a small proportion of the propellant as indicated by the Centaur upper stage, about 1/10th. So the 25,000 kg cargo capacity of the shuttle could be made up of half LH2/LOX propellant for the refueling spacecraft and half the fuel for the satellites. The volatility of LH2 makes it unsuitable for long-term station-keeping on a GEO satellite. In fact cryogenics in general aren't seen. Wikipedia lists 6 manufacturers of large commercial GEO satellites. Below is a table that lists them, their major product offerings and what I could find for what those offerings use for station-keeping and maneuvering fuel. I've included the links to where I got this info. Took about an hour and a half of Google'ing, etc. An expert in the field ought to be able to do far better. Company Methods of propulsion Platforms ------- --------------------- --------- Thales-Alenia Space[1] Ion-Propulsion using inert gas Mono-propellant Hydrazine / N2 SpaceBus 3000 Bi-propellant Hydrazine / MON3 Boeing[2] Xenon Ion Propulsion XIPS 702(various), 601HP Bi-propellant MMH / NTO 601 Lockheed-Martin[3] Electro-thermal / Hydrazine A2100 Bi-propellant various Astrium[4] Monopropellant (Hydrazine) ? Bi-Propellant (MMH/NTO) HET and Ion Thrusters Space Systems Loral[5] Bi-propellant MMH/NTO LS-1300 [1] http://www.thalesgroup.com/Portfolio...?LangType=2057 [2] http://www.boeing.com/defense-space/...xips/xips.html http://goes.gsfc.nasa.gov/text/GOES-.../section12.pdf [3] http://soliton.ae.gatech.edu/people/..._thrusters.pdf [4] http://www.astrium.eads.net/node.php?articleid=2873 [5] http://licensing.fcc.gov/myibfs/down...nt_key=-159315 Dave |
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Secret plan to privatize shuttle; now, to a next-generation shuttle.
Sorry that table got messed up, I'll try again:
Company Methods of propulsion Platforms ------- --------------------- --------- Thales-Alenia Space[1] Ion-Propulsion using inert gas Mono-propellant Hydrazine / N2 SpaceBus 3000 Bi-propellant Hydrazine / MON3 Boeing[2] Xenon Ion Propulsion XIPS 702(various), 601HP Bi-propellant MMH / NTO 601 Lockheed-Martin[3] Electro-thermal / Hydrazine A2100 Bi-propellant various Astrium[4] Monopropellant (Hydrazine) ? Bi-Propellant (MMH/NTO) HET and Ion Thrusters Space Systems Loral[5] Bi-propellant MMH/NTO LS-1300 [1] http://www.thalesgroup.com/Portfolio...?LangType=2057 [2] http://www.boeing.com/defense-space/...xips/xips.html http://goes.gsfc.nasa.gov/text/GOES-.../section12.pdf [3] http://soliton.ae.gatech.edu/people/..._thrusters.pdf [4] http://www.astrium.eads.net/node.php?articleid=2873 [5] http://licensing.fcc.gov/myibfs/down...nt_key=-159315 |
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Secret plan to privatize shuttle; now, to a next-generation shuttle.
On Jan 5, 9:47*am, Fred J. McCall wrote:
bob haller wrote: far better to launch a indenpendent space tug grapple and have it move sats and provide station keeping too. very useful when a new sat ends up in the wrong orbit or a newer sat has a failure. And that brings us back to that perennial question: Do you have *ANY* clue how much fuel it takes to change orbital planes? -- "Ignorance is preferable to error, and he is less remote from the *truth who believes nothing than he who believes what is wrong." * * * * * * * * * * * * * * * *-- Thomas Jefferson such tug graples could be put in storage orbits waiting for need, or be launched into whatever orbit needed for use. its not like they would all be launched from one location and be unable to go anywhere. strato launcher would be a ideal launcher. since most sats would either be in geo sync or on their way there before failure this would minimize orbital plane changes. it appears fred speciality is claiming everything is impossible because it hasnt been done before. if fred were here before the moon landings he would of claimed they were impossible too......... no apollo, no moon landings, heck its impossible |
#4
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Secret plan to privatize shuttle; now, to a next-generation shuttle.
fred beleves if its always been this way it always will.......
however the only thing in life thats guaranteed is change. |
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