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launcher economics
I have read that the greatest cost component for NASA in a launch is
overhead and this is very understandable. They have large fixed assetts with large costs associated with them. Consider what it must cost just to maintain the VAB or one of those launch pads. They have a large labor force that cannot be charged directly to launching so they are overhead. Even if NASA was given the launch vehicle for free it wouldnt even reduce their launch costs by half. This means that NASA will NEVER be able to launch for low cost. The best way to reduce launch cost is to reduce overhead and we have a simple relationship: Complex rockets give high overhead Simple rockets give low overhead The shuttle being very complicated will always be a high overhead system regardless of who flies it. The same thing is true of most other launch systems although to a lesser degree. For low cost launches, we need low overhead and therefor a simple launcher. For low overhead (OHD) and low direct charges, we try to reduce costs associated with the actual launch such as fees for the spaceport by launching from the ocean as does Sealaunch. For even lower direct charges we get rid of the actual launch platform and launch from the open ocean like Seadragon. We get rid of the costly support vessel. We tow the fully loaded (fuel and oxidizer) launcher to the launch site (along the equator for best performance) using a commercial ocean going tug. Launch is controlled by a small computer and power supplies onbaord the tug. Tracking is done via GPS on the launcher and tracking data and telemetry is transmitted via the satellite iridium phone network so we dont need tracking and telemetry stations. Having the launcher already loaded with fuel and oxidizer means it must be a hybrid rocket with non-cryogenic fuel such a H2O2. Previous hybrid engines had poor thrust due to low burn rate (regression rate) but the new wax hybrids are better. I can imagine a way to significantly increase the regression rate of such an engine (patent being filed) for better thrust. Engines are made very simply and meant to be clustered to fill different markets. My greatest question concerns whether they should pressure fed oxidizer or pumped oxidizer. Another question is whether to use an oxidizer tank on each engine or to use a single tank feeding all engines. A single tank might make it possible to use one large turbo pump feeding all engines at low cost. I understand that economics favor a two or three stage to orbit over a single stage to orbit and I agree. Although ppl like the idea of re-useability and think it should be more economical than expendables, I disagree and think that expendable is more economical for such a simple launcher. Our first stage is just a big dumb booster consisting of tubes filled with fuel and oxidizer feed system. Recovery and re-use is probably more costly than its worth. Ditto for the second stage. it might be worthwhile to recover the thrid stage cuz thats where the smarts and manouvering system are located but even that can be simple enough to be thrown away considering the complexity of re-entry, recovery and re-use. Its 2003 and puttin stuff in orbit aint rocket science no more so there's no good reason why it has to cost so much. |
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launcher economics
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launcher economics
The other part is that fly often is the way to amortize overhead of
staff or plant site. Example: When I take a 777 to England, it leaves Miami about 4pm to arrive England 7am, local time. Two hours to clean, restock the pantry and refuel and it's coming right back to the states at 9am. The darn things only on the ground four or five hours a day! 300 seats X $1000 round trip = 300,000 bucks a day. If it flys 300 days a year, that's an annual income of 90 million. That said, why's AA in bankruptcy? Frequency is only a part of operational efficiency. The biggest part is always the bureaucracy a transportation system has to support. [that's why nasa has to be kicked out of the space access business] ^ //^\\ ~~~ near space elevator ~~~~ ~~~members.aol.com/beanstalkr/~~~ |
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