A kerosene-fueled X-33 as a single stage to orbit vehicle.
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From: J. Clarke on 27 Mar 2010 08:48 On 3/27/2010 8:43 AM, Pat Flannery wrote: > On 3/26/2010 7:43 PM, J. Clarke wrote: >>> For military satellites it can be, as either a dangerous situation >>> develops somewhere in the world and you a reconsat imagery of it ASAP, >>> or one of your critical satellites dies (or is destroyed by someone) and >>> you need to replace it ASAP. >>> The air-launched Pegasus booster is capable of carrying eight small >>> military communications satellites aloft on a single launch, with them >>> stacked up like pancakes in the nose: >>> http://space.skyrocket.de/index_frame.htm?http://space.skyrocket.de/doc_sdat/mublcom.htm >>> >>> >> >> That's nice. Can it put them in different orbits? > > I doesn't need to; the idea is to put up small military comsats faster > than an enemy can shoot them down, in a analogy to a MIRV missile > system. As the satellites are deployed, the carrier stage will slow down > a bit do to action-reaction on each release, so that they will spread > out along a particular orbit. > Each will take a independent ASAT to destroy, so it becomes economically > unfeasible for an enemy to deploy enough ASATS to be able to keep up > with the rate the comsats can be surge launched at, though they could be > destroyed via a high-energy ground-based laser system. > When those get into large-scale worldwide deployment though, all of LEO > will be very unhealthy for every country. Oh, that's so brilliant. Iridium has 66 1500 pound satellites in 500 mile orbit. So how much actual communications are you going to be able to do with 8 122 pounders? You're not going to be able to work with handheld communications with that, and shortwave in a car can reach halfway around the world without any satellites, so what's the purpose? And how does this system beat launching them from Vandenberg, which can put up a full constellation of full sized comsats in 24 hours if the boosters and satellites are available? Hint--Orbcomm's last launch on this thing was in 1999 and they are now using conventional boosters--they gave up on that particular hare-brained scheme whose only real purpose was to justify Pegasus to stockholders. And the one recon satellite it put up has 1 kilometer resolution, which means that it can't spot an aircraft carrier, let alone a terrorist. Pegasus was a big flop. While a technical success the payloads can't do what was claimed for them and it's horribly expensive for other purposes so it has a tiny little niche.
From: Pat Flannery on 27 Mar 2010 13:59 On 3/27/2010 4:48 AM, J. Clarke wrote: > On 3/27/2010 8:43 AM, Pat Flannery wrote: >> On 3/26/2010 7:43 PM, J. Clarke wrote: >>>> For military satellites it can be, as either a dangerous situation >>>> develops somewhere in the world and you a reconsat imagery of it ASAP, >>>> or one of your critical satellites dies (or is destroyed by someone) >>>> and >>>> you need to replace it ASAP. >>>> The air-launched Pegasus booster is capable of carrying eight small >>>> military communications satellites aloft on a single launch, with them >>>> stacked up like pancakes in the nose: >>>> http://space.skyrocket.de/index_frame.htm?http://space.skyrocket.de/doc_sdat/mublcom.htm >>>> >>>> >>>> >>> >>> That's nice. Can it put them in different orbits? >> >> I doesn't need to; the idea is to put up small military comsats faster >> than an enemy can shoot them down, in a analogy to a MIRV missile >> system. As the satellites are deployed, the carrier stage will slow down >> a bit do to action-reaction on each release, so that they will spread >> out along a particular orbit. >> Each will take a independent ASAT to destroy, so it becomes economically >> unfeasible for an enemy to deploy enough ASATS to be able to keep up >> with the rate the comsats can be surge launched at, though they could be >> destroyed via a high-energy ground-based laser system. >> When those get into large-scale worldwide deployment though, all of LEO >> will be very unhealthy for every country. > > Oh, that's so brilliant. Iridium has 66 1500 pound satellites in 500 > mile orbit. So how much actual communications are you going to be able > to do with 8 122 pounders? You're not going to be able to work with > handheld communications with that, and shortwave in a car can reach > halfway around the world without any satellites, so what's the purpose? Military communications in wartime. > And how does this system beat launching them from Vandenberg, which can > put up a full constellation of full sized comsats in 24 hours if the > boosters and satellites are available? Because in a lot of cases, the boosters and satellites wouldn't be available. The Pegasus-launched small military comsats were a response to the Soviet development of operational ASATs that could destroy our military comsats in wartime, leaving us with no ability to get info back and forth between troops and C&C. > Hint--Orbcomm's last launch on this thing was in 1999 and they are now > using conventional boosters--they gave up on that particular > hare-brained scheme whose only real purpose was to justify Pegasus to > stockholders. With the fall of the Soviet Union, a war with Russia looked a lot less likely, so we didn't need the ability to launch a lot of small military comsats. Now that China has demonstrated a ASAT ability, that may all change again. > Pegasus was a big flop. While a technical success the payloads can't do > what was claimed for them and it's horribly expensive for other purposes > so it has a tiny little niche. It can also launch small inspection-destruction ASATs into any orbital inclination desired as was demonstrated by the DART mission that rendezvoused with the Pegasus-launched MUBLCOM satellite. The military has also expressed interest in using Virgin Galactic's White Knight 2 as a launch vehicle for small satellites. Besides that, there was a project by AirLaunch and DARPA for the QuickReach system to slide a satellite booster out of the cargo bay of a C-17, and ignite it as it descends under a parachute, again to give rapid launch into any orbital inclination capability to military payloads: http://www.globalsecurity.org/space/systems/quickreach.htm This is part of the DARPA/Air Force Falcon Project: http://en.wikipedia.org/wiki/DARPA_Falcon_Project#Small_Launch_Vehicle Pat
From: hallerb on 27 Mar 2010 13:04 On Mar 27, 1:59�pm, Pat Flannery <flan...(a)daktel.com> wrote: > On 3/27/2010 4:48 AM, J. Clarke wrote: > > > > > > > On 3/27/2010 8:43 AM, Pat Flannery wrote: > >> On 3/26/2010 7:43 PM, J. Clarke wrote: > >>>> For military satellites it can be, as either a dangerous situation > >>>> develops somewhere in the world and you a reconsat imagery of it ASAP, > >>>> or one of your critical satellites dies (or is destroyed by someone) > >>>> and > >>>> you need to replace it ASAP. > >>>> The air-launched Pegasus booster is capable of carrying eight small > >>>> military communications satellites aloft on a single launch, with them > >>>> stacked up like pancakes in the nose: > >>>>http://space.skyrocket.de/index_frame.htm?http://space.skyrocket.de/d.... > > >>> That's nice. Can it put them in different orbits? > > >> I doesn't need to; the idea is to put up small military comsats faster > >> than an enemy can shoot them down, in a analogy to a MIRV missile > >> system. As the satellites are deployed, the carrier stage will slow down > >> a bit do to action-reaction on each release, so that they will spread > >> out along a particular orbit. > >> Each will take a independent ASAT to destroy, so it becomes economically > >> unfeasible for an enemy to deploy enough ASATS to be able to keep up > >> with the rate the comsats can be surge launched at, though they could be > >> destroyed via a high-energy ground-based laser system. > >> When those get into large-scale worldwide deployment though, all of LEO > >> will be very unhealthy for every country. > > > Oh, that's so brilliant. Iridium has 66 1500 pound satellites in 500 > > mile orbit. So how much actual communications are you going to be able > > to do with 8 122 pounders? You're not going to be able to work with > > handheld communications with that, and shortwave in a car can reach > > halfway around the world without any satellites, so what's the purpose? > > Military communications in wartime. > > > And how does this system beat launching them from Vandenberg, which can > > put up a full constellation of full sized comsats in 24 hours if the > > boosters and satellites are available? > > Because in a lot of cases, the boosters and satellites wouldn't be > available. > The Pegasus-launched small military comsats were a response to the > Soviet development of operational ASATs that could destroy our military > comsats in wartime, leaving us with no ability to get info back and > forth between troops and C&C. > > > Hint--Orbcomm's last launch on this thing was in 1999 and they are now > > using conventional boosters--they gave up on that particular > > hare-brained scheme whose only real purpose was to justify Pegasus to > > stockholders. > > With the fall of the Soviet Union, a war with Russia looked a lot less > likely, so we didn't need the ability to launch a lot of small military > comsats. > Now that China has demonstrated a ASAT ability, that may all change again.. > > > Pegasus was a big flop. While a technical success the payloads can't do > > what was claimed for them and it's horribly expensive for other purposes > > so it has a tiny little niche. > > It can also launch small inspection-destruction ASATs into any orbital > inclination desired as was demonstrated by the DART mission that > rendezvoused with the Pegasus-launched MUBLCOM satellite. > The military has also expressed interest in using Virgin Galactic's > White Knight 2 as a launch vehicle for small satellites. > Besides that, there was a project by AirLaunch and DARPA for the > QuickReach system to slide a satellite booster out of the cargo bay of a > C-17, and ignite it as it descends under a parachute, again to give > rapid launch into any orbital inclination capability to military > payloads:http://www.globalsecurity.org/space/systems/quickreach.htm > This is part of the DARPA/Air Force Falcon Project:http://en.wikipedia.org/wiki/DARPA_Falcon_Project#Small_Launch_Vehicle > > Pat- Hide quoted text - > > - Show quoted text - well we DONT need is any more satellites being destroyed on purpose. as it runs the serious risk of making LEO unusable.......... thats a big price to pay, just to demo the capability.
From: hallerb on 27 Mar 2010 18:24 > > The "lack of understanding" would seem to be yours. �SSTO *does* lower > cost, since it eliminates all that pesky 'stacking' and such, allowing > smaller processing crews. �If such a vehicle is also reusable (which > is different from SSTO) you quickly approach airliner cost scales. > SSTO can only cut costs if the finished product has good weight capacity
From: Marvin the Martian on 27 Mar 2010 22:33
On Sat, 27 Mar 2010 15:24:32 -0700, hallerb(a)aol.com wrote: >> The "lack of understanding" would seem to be yours. �SSTO *does* lower >> cost, since it eliminates all that pesky 'stacking' and such, allowing >> smaller processing crews. �If such a vehicle is also reusable (which is >> different from SSTO) you quickly approach airliner cost scales. >> >> > SSTO can only cut costs if the finished product has good weight capacity It would require such a large heat shield that it would have very little left for payload. The SSTO is a dream of people who don't understand the rocket equation who think that going into space should be like driving the family car. |