|
|
|||||||
|
|
|
Thread Tools | Display Modes |
|
#1
September 18th 03, 09:07 PM
|
|||
|
|||
market size as a function of launcher size
Although it would be very nice to have a very heavy launcher like
Saturn V or Energia, there is little market for it. The small market doesn't justify development or the infrastructure for it. The market can handle various smaller launchers. Is there any way to use combinations of smaller launchers to achieve a very heavy launcher when it is needed without developing the infrastructure for the very heavy launcher? This is done in limited fashion by strapping various SRBs onto rocket cores but this doesnt get us into the realm of a very heavy launcher without starting with a fairly heavy launcher. Is this because of the need for the infrastructure for the heavy launcher (pad, etc?) I assume that you couldnt just keep strapping shuttle SRBs together to achieve sufficient lift because you would exceed the capacity of the pad and support equipment. However, what if we didnt need the infrastructure but instead used a launch from water as proposed for Seadragon. We might then be able to just keep strapping SRbs together ad infinitum. Maybe clustered hybrids would be a good idea for this since they can be better controlled. 
|
|
#3
September 18th 03, 10:22 PM
|
|||
|
|||
|
market size as a function of launcher size
Parallax wrote: Although it would be very nice to have a very heavy launcher like Saturn V or Energia, there is little market for it. The small market doesn't justify development or the infrastructure for it. The market can handle various smaller launchers. Is there any way to use combinations of smaller launchers to achieve a very heavy launcher when it is needed without developing the infrastructure for the very heavy launcher? A medium-lift (which I define to be 40-80,000 lb. payload) launcher can substitute for an HLLV in some circumstances, such as manned lunar or Mars flights. A large majority of the Initial Mass in LEO (IMLEO) of a lunar or Mars ship will be propellants, which are easily divided into smaller packages. Several tanker flights of a medium-lift RLV can deliver propellants to a propellant depot in LEO. An additional flight can deliver the hardware, which is then docked to the propellant depot where the tanks are filled. That eliminates the need for an HLLV and gives us a vehicle which can be used for many other purposes as well.
|
|
#4
September 19th 03, 04:21 AM
|
|||
|
|||
|
market size as a function of launcher size
Dick Morris wrote in message ...
Parallax wrote: Although it would be very nice to have a very heavy launcher like Saturn V or Energia, there is little market for it. The small market doesn't justify development or the infrastructure for it. The market can handle various smaller launchers. Is there any way to use combinations of smaller launchers to achieve a very heavy launcher when it is needed without developing the infrastructure for the very heavy launcher? A medium-lift (which I define to be 40-80,000 lb. payload) launcher can substitute for an HLLV in some circumstances, such as manned lunar or Mars flights. A large majority of the Initial Mass in LEO (IMLEO) of a lunar or Mars ship will be propellants, which are easily divided into smaller packages. Several tanker flights of a medium-lift RLV can deliver propellants to a propellant depot in LEO. An additional flight can deliver the hardware, which is then docked to the propellant depot where the tanks are filled. That eliminates the need for an HLLV and gives us a vehicle which can be used for many other purposes as well. In some cases, this could work. However, if teh medium lifter is expensive, then several are even more so. Is the cost proportional to the number of launches? Would the cost be significantly less with fewer but larger launches? Truax says the cost does not increase significantly with rocket size so big rockets are about the same overall cost as smaller ones to launch (cost is mostly overhead). However, there is little need for HLLV but when it is needed, it might really save $ if the development and overhead cost ws not much more more than a smaller rocket. So, this means that clustering smaller rockets might make sense if these smaller rockets are used when smaller payloads are desired. For this, hybrids might really make sense. They are fairly simple and reliable with better performance than pure solids. They are almost environmentally benign and some of the fuels (and oxidizers) are very safe and easy to handle. Maybe the H2O2/Wax combination would be good for his. One could imagine very cheap production of many of these engines and an easy clustering system for arbitrary enlargement. Tow the cluster to near the equator in the ocean away from silly govt regs, tilt it upright as in Seadragon and launch. Each engine could be fed from a common oxidizer tank with its valve independently controlled to balance the cluster thrust or to shut one down if it went bonkers. Outer engines in cluster could be fed oxidizer to burn faster for faster staging and then are ejected from the core. Inner engines initially have low thrust but on staging they pour it on. Forget reuseability, this is cheap enough to throw away after each use. No nasty Nitrogen tetroxide, no ammonium perchlorate, no cryogenics, just cheap, reliable, few safety problems and environmentally benign. I know I greatly oversimplify, but basically take a large wax cylinder, drill a hole down the middle, wrap the outside with fibreglass cloth, carbon fiber matting using boat building technology so its done in quantity, add the nozzle and pressure and temp guaging, and a computer controlled throttle valve. Oxidizer tanks are made from welded Al with carbon fiber matting around outside resined on. Its just a Little Dumb Booster that can be clustered to make various sized Big Dumb Boosters when needed. I clearly have too much time on my hands since I know little about rockets.
|
|
#5
September 19th 03, 03:15 PM
|
|||
|
|||
|
market size as a function of launcher size
Hi all,
If there is going to be a HLLV (defined as a launcher capable of placing 40Mt+i nto LEO) in the future which one of the following will be the first customer? 1) NASA With a A Moon/ Mars mission 2) DoD to place large military satellites- perhaps a Space based laser 3) Commercial organisation - perhaps launching big comsats. 4) Other - please explain. ta Ralph Mike Rhino wrote in message ... "Parallax" wrote in message . com... Although it would be very nice to have a very heavy launcher like Saturn V or Energia, there is little market for it. The small market doesn't justify development or the infrastructure for it. The market can handle various smaller launchers. Is there any way to use combinations of smaller launchers to achieve a very heavy launcher when it is needed without developing the infrastructure for the very heavy launcher? It is possible to have a lunar program with boosters smaller than Saturn V. Suppose you send supplies to the moon on 5 ships. Some of these would be permanent like housing and some would be consumables like food. Then you send 3 astronauts to the moon. Two years later, you send fuel so they can get off the moon. They meet up with another refueling ship and return to Earth. If you set up a lunar program like this, then the Lunar market might end up being bigger than the low Earth orbit market. After China's space flight, the low Earth orbit area could get crowded. The US to shut down the shuttle and ISS and set up a lunar program. This would require new rockets instead of using existing ones, but we are already planning to spend money on OSP. We could cancel the OSP and spend that money on Lunar rockets.
|
|
#6
September 20th 03, 02:43 AM
|
|||
|
|||
|
market size as a function of launcher size
"Parallax" wrote in message
om... Although it would be very nice to have a very heavy launcher like Saturn V or Energia, there is little market for it. The small market doesn't justify development or the infrastructure for it. The market can handle various smaller launchers. Is there any way to use combinations of smaller launchers to achieve a very heavy launcher when it is needed without developing the infrastructure for the very heavy launcher? It is possible to have a lunar program with boosters smaller than Saturn V. Suppose you send supplies to the moon on 5 ships. Some of these would be permanent like housing and some would be consumables like food. Then you send 3 astronauts to the moon. Two years later, you send fuel so they can get off the moon. They meet up with another refueling ship and return to Earth. If you set up a lunar program like this, then the Lunar market might end up being bigger than the low Earth orbit market. After China's space flight, the low Earth orbit area could get crowded. The US to shut down the shuttle and ISS and set up a lunar program. This would require new rockets instead of using existing ones, but we are already planning to spend money on OSP. We could cancel the OSP and spend that money on Lunar rockets.
|
|
#7
September 20th 03, 06:36 AM
|
|||
|
|||
|
market size as a function of launcher size
In article ,
ralph buttigieg wrote: If there is going to be a HLLV (defined as a launcher capable of placing 40Mt+i nto LEO) in the future which one of the following will be the first customer? 1) NASA With a A Moon/ Mars mission 2) DoD to place large military satellites- perhaps a Space based laser 3) Commercial organisation - perhaps launching big comsats. 4) Other - please explain. You forgot 5) None of the above -- no HLLV any time soon. Which is by far the likeliest of the bunch. Especially after the station debacle, no way no how is Congress going to hand NASA a blank check for a Moon/Mars project. Apollo *will* *not* happen again. Suggestions to the contrary are ludicrous fantasies. (It is not beyond hope that manned exploration might happen again... but it will not be done the Apollo way, developing a giant launcher and a new spacecraft in a big hurry. Vastly lower costs are absolutely necessary, so it will have to use existing launch systems -- which must be much cheaper than today's -- and take a far more cost-constrained approach to the spacecraft and the mission. JSC is probably incapable of doing this; NASA as a whole may be incapable of doing it.) DoD has occasionally shown interest in launching large things, but the already-debatable requirements for it have largely evaporated with the end of the Cold War. Even the spysats are shrinking, not growing. Giant comsats are not as popular today as they were five years ago. And even the extreme high end of the market has a long way to go before it will outgrow the EELV Heavy configurations. There will be no market there any time soon. Other commercial markets are highly speculative, and are more likely to want lots of small launches than a handful of huge ones. -- MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer first ground-station pass 1651, all nominal! |
|
|
#8
September 20th 03, 07:22 AM
|
|||
|
|||
|
market size as a function of launcher size
"ralph buttigieg" wrote in message
... Hi all, If there is going to be a HLLV (defined as a launcher capable of placing 40Mt+i nto LEO) in the future which one of the following will be the first customer? 1) NASA With a A Moon/ Mars mission 2) DoD to place large military satellites- perhaps a Space based laser 3) Commercial organisation - perhaps launching big comsats. 4) Other - please explain. Either NASA or the Chinese government. Commercial organizations aren't that big and probably won't be able to compete against the Chinese. Spy satellites aren't that big. If Bush goes loony, he might want to launch a few weapons, but I doubt it. By first customer, are you referring to person A paying person B? It will probably be a while before anyone pays for a complete launch, but somebody like Tito could buy a ride. If we had a hotel on the moon, a company might pay for a complete launch to get supplies, machines, or people up there.
|
|
#9
September 20th 03, 01:29 PM
|
|||
|
|||
|
market size as a function of launcher size
MattWriter wrote in message ... If there is going to be a HLLV (defined as a launcher capable of placing 40Mt+i nto LEO) in the future which one of the following will be the first customer? BRBR The only thing I can think of that is even slightly likely to happen soon to make the HLLV a going proposition is the space-based laser. IF it's built, indididual lasers will weigh 40 tons or more by some estimates. You can either build a heavy-lift or do on-orbit assembly. If I were in charge, I would build the heavy lifter as the simpler and probably cheaper long-term solution. I tend to agree. The experimental SBL which is being worked weights 20 tonnes. The deployable satellite is bound to be bigger. The SBL project is ticking along at a slow pace at the moment with only 10-20% of the funding originally requested. (have a look at www.highfrontier.org for more details) I'll be interested to see what happens if the Chinese move substantially into space. If the US felt that Chinese space power was a threat to American space systems there would be a case for the early deployment of SBL to maintain US control of Space. ta Ralph
|
|
#10
September 20th 03, 03:46 PM
|
|||
|
|||
|
market size as a function of launcher size
If there is going to be a HLLV (defined as a launcher capable of placing
40Mt+i nto LEO) in the future which one of the following will be the first customer? BRBR The only thing I can think of that is even slightly likely to happen soon to make the HLLV a going proposition is the space-based laser. IF it's built, indididual lasers will weigh 40 tons or more by some estimates. You can either build a heavy-lift or do on-orbit assembly. If I were in charge, I would build the heavy lifter as the simpler and probably cheaper long-term solution. Matt Bille ) OPINIONS IN ALL POSTS ARE SOLELY THOSE OF THE AUTHOR
|
|
| Thread Tools | |
| Display Modes | |
|
|
Linear Mode
